Ya, My thinking exactly! As for where to start, I start at the beginning and finish at the end Bumping this as it took me an age to find, theres around 300pics going in here this eve, so if the lights dim on here dont be shocked Brian.
Onto stripping the 8v Gti head, Out with the cam, nuts opened nice and easy and uni-formally to prevent stressing the cam.. Off with caps and nuts.. Out with cam.. Back on with caps and nuts for the time being for safe keeping.. Next, the buckets have to come out, I use a valve lapping tool to whip them up, very fast.. Pressed down firm... Out she comes... Next, a plug socket is used to tap each keeper, this shakes the grip the collets have inside them and makes pressing down the keeper easier...one sharp tap to each, mind lifter bore walls.... All shook up!, .. One broken portable bench mortiser converted to one very efficient valve compressor, that isnt stressful like the other 'c' clamp style gits of yokes(Sorry, I hate them) Bit of ply for a base, and a bit of 6mm mdf to stop valves being pushed down when being pressed... Line her up... Press, Collets out....sometimes they'll fall out, other times a small bit of wire is needed to coax them off valve stem... Release press.... Remove... Remove both springs... I can race across head in about a minute doing it with the press, and it doesn't cause me to swear once...and there's great access around keepers... Removed the rest of the collets, keepers, and springs.... Valves pushed down and removed... Onto the broken water flange bolt, I was thinking this wouldn't be easy and how right I was, anyways..... The usual plan is, heat, wd40, swear, etc, this one was well in so good luck to all them, out with the drill, bore a hole in order to tap in a torx bit, and hope it twists out....
More heat, wd40, etc, and still no go, torx bit broke off in the bolt, LOVELY... Time to start digging.... Holes bored around bolt... Holes joined up with a small chisel... Bit of digging and out comes the torx bit tip... More digging and out comes the bit of bolt that was frozen in there.... Hole washed out and flange cleaned up, should be all dry of thinners tomorrow to put some epoxy(JB Weld) in there, once its sanded flush and tapped itll be perfect, crisis averted. Onto the flange repair... Its fully dry now and has been wiped out again, JB weld epoxy below, to be mixed 50:50. Epoxy spec> Properties (psi) Tensile Strength: 3960 Adhesion: 1800 Flex Strength: 7320 Tensile Lap Shear: 1040 Shrinkage: 0.0% Resistant to: 500 F This is better done indoors as the temperature causes the epoxy to get a bit thinner and easier work/pour. Mix.. Fill... Done, I can sand flush tomorrow and re-drill/tap after... I got another one to try yesterday and Im pretty happy with it too, I may need some for bonding any carbon fibre parts I need attached to other stuff, Ill also need it for bonding a few bits inside the slide throttles. Its a bit thinner than JB weld so will suit me a bit better where tolerances are involved. Heres a pic of said epoxy, it contains suspended titanium particles as a filler material. :wub: So last night I decided to do a small test run with the carbon fibre to see what its like to work with, Ive read a billion books on it and read a pile of F1 fab stuff, but as I always find hands on beats all reading. I know there's a few guys on here very interested in this stuff, so what I found out, Ill share. I have done a lot of fibre glass work before but no carbon fibre or kevlar work. The process is similar to glassing, but the material costs are far more, so, not good to screw up on a big run, hence this small test. I wanted to make something that would test cutting the fabric, laying it, its general strength when done, the resin work time, trimming/sanding the finished item, water papering it, and polishing it. After a quick think of any handy small engine part I could make that wouldn't use hardly any fabric, I came up with none, so I had a fast look around, and spotted a spoon left on the table, so that was it, a spoon it was. Not an engine part I know I know, but it had a few shapes I wanted to try out, concave/convex shapes, flat areas, and a thin neck, perfect!. Its also used damn all fabric, which was a major plus too. So anyways, onto the job.... I had read that a special scissors was needed to cut the fabric, I thought Id have to buy one, BUT a normal scissors works just fine. So, a 50mm wide strip was cut off the roll... I then cross cut it into 5 pieces a bit longer than the spoon... One thing I have to get for the engine parts later is pin strip masking tape, the fibre frays very easy at the edges, and Id say if you were handling it a lot, all the weave would go out of line. But it was ok on this job, as the lay-up was pretty easy. To give you an idea of how thick 200g carbon fibre is, the 5 layers came to 1mm when measured dry... The spoons in question, they are the same size and shape exactly, Ill be using the two, as I want to have a second one to hold over the top to use as a guide when painting on resin, as I wont be able to see the bottom one... As a release agent Im using standard shoe polish, for the better items ill be using standard carnauba wax on the moulds. Wax on, wax off The resin, this is to be mixed 5 resin, to 1 hardener....Im using a small paint brush to apply resin... Mixed.....if your mixing big amounts use a glass container, as this stuff cures its gets pretty hot (60degrees)(exothermic reaction)... This is approx 30min hardener, time goes fast so organise yourself.... Bottom spoon painted with a good coat of resin..... First strip laid down, pressed in well to expel any excess resin, you dont want any resin between them really, just enough to wet them... 1st layer wetted gently with more resin....(lightly)... 2nd pressed down firmly again to expel any excess, I also laid down a few strands going from stem to bowl part of spoon to strengthen neck... Wetted again, another layer put down, and a few more strands...... Wetted again and another layer applied.... The last layer I didn't get a shot of as I hadn't time to take it, resin going off rapid at this stage as you can see in the lid above.... Again before it went to the gel stage I pressed all layers down hard to expel any excess resin between them, resin is not as strong as carbon fibre, so you want just enough in there to wet fibre, but not any extra..
Fecking class act expert welding Brian. But I won't believe that you built the welding machine witout piccys!
Approx 2hrs later it was rock solid..... Spoon snapped out very easy(Thank christ!) I trimmed off any extra fibre I could with the scissors, the epoxy is very hard so get as near as you can... I cleaned it with rubbing alcohol and propped it up, I wanted to give it one more coat either side to give me a layer to wet sand... Left it overnight to cure, gave it around 16hrs....Marked outline of spoon again with a sharp scriber.... I originally thought that Id be able to belt sand upto the line, but it wasnt the case, the belt sander just sands the resin away, and furs back the fibre, it wont sand it.... So out came the dremel with the mini disc, I honestly think there's no other way to cut this stuff, bar maybe a fine toothed blade, but that would strain things alot Id say on smaller Items..... Cuts handy... Done, and finished to approx shape with dremel, time to start sanding.... I started with 320 paper, spent 5mins sanding under the tap.... When I was happy there was no hard edges I moved onto 600 water paper and washing up liquid.... Another 5mins with some 1500 paper and w/liquid...getting there... Some 2000 paper and w/liquid..... Looking perfect, with no un- sanded spots... Dried.... I used some old car wax I had to polish it up, 2 coats, the usual waxing lark.... Buffed..... Extremely happy with how It all went, the finished item even though its a spoon looks and feels unbelievable, its also extremely strong at the neck... Test complete, it was far easier than I thought to work, the resin isnt like glassing resin either, as in it doesn't stick to your hands/tools/desk/etc, its very like water, with no bad smell at all. It does go off pretty quick though, 30mins and its gone, so a lot of prep is needed on a big job. This way also shows how a water papered surface can be made to look just as good as the surface that was against the mould(flat/shiny straight off) So that's going to simplify my intake a fair bit given that I can get a perfect surface on the outside(Mould will be on inside) without having to have an outer mould too. Ill probably be rigging up a vacuum bag for the intake, that way I can make sure the fibre is compressed fully onto the mould all over before it dries, anyway, more on that later, I just wanted to get a feel for it first in the line of cutting, and the resins. More materials arrived, and a few milling/boring bits too...... This is a boring head, its a fantastic tool for fine stuff and can bore/finish a large range of hole sizes. It does need a pilot hole though but that can be made with a hole saw or a large twist drill bit. The idea is, you bore the hole say 3mm under finished size, then you use the boring head to finish it out to its exact diameter, and it also ends up very round, and exactly where you want it via positioning on the skimmer table(s). It uses one cutter, the whole tool spins, the top of boring head can be off-set via the vernier adjusting screw on the side, it can then be locked and the quill lowered to bore hole. You work slowly upto the finish size a bit at a time. For exact holes say, bores for buckets, this tool is ideal, and Ill also be using it to cut the lifter bores in my 16v head. You can also control final diameter of the hole by spinning the cutter faster(within its limits) this has the effect of forcing out the cutter bar through centrifugal force, and therefore taking an even lighter finish cut. First off Ill be cutting the 4 holes in the slide throttle assembly with it. Ill have to make an adaptor in order to mount it in the skimmer, but thats handy enough... Here it is with a boring bar in the middle hole.... And in the outside hole.....you can see how the head can be adjusted in order to increase cutting diameter at cutter head.... And a longer bar fitted....for large holes...again, can be adjusted. Boring head has a full cutting range from approx a 12mm diameter hole, upto 200mm in diameter... Demo of how it would be set to fine cut lifter bore... Vernier adjustment.... 7mm reamer for finishing new valve guides after installation.... Various hex stainless screws for slide throttles.... 6mm bore phosphor bronze bushes for slide throttles... Various springs.... Pure PTFE, this is a plastic with excellent if not the best bearing and anti stick properties. Its so slippy one side has to be etched(brown) in order for them to be bonded to anything. Again, for the throttles... Some more aluminium for the cutter head for skimmer in order to surface the heads... Some 2.5mm brass, and some 6mm aluminium plate....
Forgot these pics, last of the plate I got for skimmer, 15mm thick, I can finally get back to actually doing stuff now as I have a fair bit of materials in again to keep me going B) Another arrival this morning, 170gsm Kevlar for intake trumpets..... because Ill be starting off with a Schrick 288 cam and probably moving up, I want to clearance around the lifter bores before I go any further, with a 288cam fitted the cam lobes run very close to edge of bores, so Ill be removing a bit of alloy from that area just to be on the safe side, that way I can always fit what I want without having to do it again. First, sanded the epoxy flat...ready for drilling and tapping... Standard cam left back in to check clearance and mark where I need to remove material.... Marked...doing this before the head is cleaned makes things easier see.. One bad picture of the dremel fitted with a 3mm straight carbide burr.... One side done... Other side done... Cam re-fitted to check new clearance... All sharp edges removed with a 25mm flap wheel... Done... Ill be cleaning up head a bit next before the real work starts... Started slide throttle plans last night, few pics below showing workings before I finish drawing as its a bit easier to see how it goes together/works before I fill in more stuff on it... Its drawn in the idle mode, its pretty basic, top and bottom alloy plates, brass throttle plate in the middle, bottom plate machined to brass plate thickness so that it sits into it. Below the brass plate there's 2) 12mm grooves cut, in these grooves goes the ptfe bearing plastic so the brass slides nice and easy. Below these ptfe strips are the counter bore holes to hold the whole lot onto the manifolds. I have to draw in spring mounts, Idle stop, full throttle stop, and linkage yet, but ya get the idea. Ill also have to mount an Idle switch, wot switch, and a potentiometer fixture too, but thats fairly minor. Slide plate highlighted... Ill prob be machining away alot of the top and bottom plates too where the material isnt needed on the outsides to get rid of a bit of the bulk. Hope to finish plans later tonight,
Finished off drawings this eve and milled out the main bottom plate as shown above. I could have done this on the bridgeport, but I used the router to show what can be done with basic tools, not everyone has a bridgeport... So, onto the job, all this milling took around 30min, so the router is by no means slow. You will need a very good quality one though, that is one that did not come from aldi...Its needs to have a strong spindle, and good bearings. German ones are good B) A normal tungsten tipped bit can be used to cut the plate. Heavy cuts can be taken to rough it down to near final dimensions, rough being 1.5mm deep, and finish up with a light cut of say, .25mm to bring you to final dimension, this will ensure the best surface finish. wd40 or something like that is used as a cutting fluid, and cuts are taken very slow. If your not used of using a router, then dont try it, or it could kill you, or take out your eye if your not careful and Ill get the blame.... ....anyways, onto the pics... The plate, the bit, and my coffee...(most important) Heres the approx shape Ill be milling to give ya the jist.... Zie bit... The router, just zeroing bit before I start... Ill let the next few pictures roll, there just showing the various stages of cut/depth etc...these are all rough cuts to get down to near my sizes... Finish depth cut on slide slots.. Bang on including clearance... Time to start roughing down the centre section... Nearly there...finish cut to go... Oiled up ready for last cut... Finished... Silky... Getting there... End view, ptfe strip sit into grooves, brass throttle plate sits onto them, the ptfe keeps the brass up approx .15mm of the bottom alloy plate to make sure it slides nice n easy. Update, got a nice bit of machining done this eve, started by marking out lower plate with engineers layout pen, makes things easier see... Punched main hole centres and drilled them out... Bored with a 3mm pilot... How it looks from the other side... Open them up to 6mm, this bit has a 3mm auto pilot tip built in... Drilled... The holes in the grooves need to be counter bored for hex heads that will hold the assembly onto the runner pipes... Counter bore bit... Cuts a square shouldered recess... Done... Next, I want to get rid of some alloy on the underside of bottom plate, this will take some weight away for me, Ill be keeping to the shape of the runners top flanges which Ill also be making... One router bit and guide bush, the bush runs along an edge of any sort, and the bit is automatically guided, the bush is 14mm and the bit 10mm so Ive 2mm to take off flange drawing dimensions when marking template. That way, the 2mm difference between the bush edge and bit will be compensated for and the cut line will end up in the right spot...Its handy, it just sounds a bit complex. Bit and bushing... Marking out flange profiles... Coping saw, chop chop... Template screwed on using the port centre 3mm pilot holes to fix...
Bit and bush fitted... Height bar placed in-front to rest router on when doing the outer cuts, keeps router base level at all times and stops tipping... First roughing cut... Second... Final super light finish cut, the camera picks up the surface funny, makes it look all over the place... But its flat... Jig off, one side done... Ready for other side... Rough cuts....etc...same as first side... Few shots of it cleaned up, marking fluid gone... Underside... Runner side, and hex fixing screw... Surface finish... Major machining done, and not a cnc in sight I have to fit the independent Idle control screws/drillings next, I want to have one on each port for total balancing control. Few more bits for both the build and the car In general, Got a set of G60 steels today, Thanks again George. And one of the more interesting stainless pipes for the exhaust build, its perforated.... Hoping to spend a good while tomorrow on the throttles, Small update, FINALLY got the exact sand I wanted for casting finer parts. I took an age to find a company that would actually sell this to a normal 5/8th.. I can now finish the casting thread with this, as it will let me get a feel for this sand too. This sand is oil bonded sand, and not water bonded which is used for rougher castings. The oil in this sand will not boil like the other, therefore pitting on part surface is reduced A LOT. Also got the flux off the same crowd, this helps bring any contaminants to the surface before you rake off the dross(scum) before pouring. Spent an hour or two today re-fitting standard suspension, also removed the dirty mud flaps, from this> To this, standard height and slightly cleaner machine> Ill link the casting thread to here when its finished end of week, and Ill also include the flange casting test in here too. Theres going to be a fair bit of casting on this engine too, so its no harm to link thread for more info/insight.
Got the shells, Going to do a casting test run of the water outlet flange this eve to test out sand. Want to see how much detail it holds for the few throttle body bits I need. Right, so if some of you are new to this thread I suggest you read this thread in order for this next part to make ANY sense. For everyone that has read that thread this next bit will make complete sense(I hope). As you know I got the sand I had been waiting for the last day, its a very fine casting sand and I had to try it out because I need to get a feel for it, and how it works. These parts your going to see below are the first two parts Ive ever cast. Ill need cast parts for this engines intake so a water flange was as good a part as any to test out the sand on. So anyways, onto the casting test... If youve read the other thread these patterns below will make sense to you, and how they came about being made... The layout of the pictures below are in the order I did it in, so Ill host them in that order... I fixed the pattern halves onto the parting plate, I had to make a new parting plate as I drove over the other one last week :rolleyes: One half fixed... Turned upside down... Other half fixed, must be fixed as accurately as possible to be opposite its other half or you'll end up with a massive parting line in the finished part... All screws and holes filled... I prepped the charge in the crucible, more smashed up water pumps, there great!!... Test fit, and set up burner pipe... Next, I made the cores for the flange using the plaster core box... I need two, as the main pattern is setup for two flanges...I put a nail in the middle to make handling them easier...remember, this sand is just bonded with oil, it doesn't go off or dry, its as Is once the core box is opened, Its amazing stuff when packed... Full, and packed... Out of core box... And one more... Next, I filled the main mould... All filled and packed... Turned over the whole lot and got to work filling the top... Full... Scooped out this area to funnel in molten metal to mould... Lifted off top mould section...and removed parting plate c/w patterns screwed on...this is the bottom half of mould below... Removed the dowels and cut fill gates from dowel holes into rear of flange...this is the top section... Sliced a small flat area off cores as I need a bit of metal thickness in this area for flange bolt counter bores, so that a socket will fit onto bolt head, and clear flange its-self... Placed cores in mould... Made a few vent holds in top mould half before I fitted it, 2mm wire, job done, ... Top fitted, say goodbye!.. Lit smelter... Takes a second to cop on and warm up then off she goes... After 5min... The next bit Ive no pictures of because Ive only two hands, and If I asked anyone to take pictures at 12 o clock at night they'd probably think I was actually demented... What I did was scoop off as much dross as I could, added a spoon of flux, stirred it, little more heat for a min, then raked off the rest of the dross(scum) before I poured it into mould. Full... Now...the moment of truth, were the patterns correct, did the cores collapse in main mould, did I pack it enough... Gave ten minutes and started digging...it filled perfect...nice... Lifted up, its still very hot, vent hole did its job well... Close-up of fill gate/runner... I cut them apart broke off fill gates and shook out the core sand...
A quick run on the beltsander removed most of the flash/gates etc either end, the belt died half way through, I have to take down the flange face approx 1.5mm more yet, but thats minor... Close-up of extra material needed for counterbore created by shaving the core moulds... Few random pictures, they still need a bit of grinding/linnishing, Im extremely happy with the over-all finish direct from mould... You can see the flange is 1.5mm too high yet, there's a bit of material left on there so I can finish them flat... The bits and pieces... A quick run on the beltsander removed most of the flash/gates etc either end, the belt died half way through, I have to take down the flange face approx 1.5mm more yet, but thats minor... Close-up of extra material needed for counterbore created by shaving the core moulds... Few random pictures, they still need a bit of grinding/linnishing, Im extremely happy with the over-all finish direct from mould... You can see the flange is 1.5mm too high yet, there's a bit of material left on there so I can finish them flat... Offered up to head, looking good, hose is real snug too, tomorrow, Im going to finish sealing face, and drill holes, that should be it then, sand testing done. I may pack it even harder the next time, and give it more vent holes, see if I can get an even better surface finish, although, I suppose, its not too bad at all, for the first time. Im putting this picture up once again, It was the most amazing thing Ive seen in a while, it takes you by surprise to actually see the parts emerge from the sand Im very happy all in all with the results to say the least Postman was good to me today, one of the ballscrews came for skimmer, this is for the quill/head up and down adjustment, the specs of screw are below... RM2505 25mm in Diameter 5 degree lead angle 3.175mm ball diameter Dyn.kgfCa 1280 Sta.kgfCoa 3110 Rigidity Kgf/umK 35 This is a high tech bit of kit and is machined for coupler one end to accept the stepper motor I was talking about earlier on. I tracked these down in Hong Kong, they came from a proto-type machine built for display purposes for a trade show. These would normally be approx 600euro each but they can be had for a fraction of that if your building a machine that you can design them into. The postage cost for this was more than the actual cost! The main bearing block which goes on the stepper motor end, there are two axial mounted bearing in this, you preload them with the nut on the shaft, this means there is no axial play in the screw/quill box when mounted. A close-up of main nut, this is no normal nut, its filled with ballbearings which recirculate around the rolled rod. This can carry immense loads and still hold its position. Its main feature is its turning low friction, and high accuracy with minimal backlash(play). You can just see the balls inside... The end of shaft is turned down to accept block, pre-load nut, and coupler, the coupler is slightly flexible with allows for any inaccuracy's between the rod, and stepper motor mount... The free end just has a locating bearing fitted, its a standard bearing and is for positioning only, it carries no load... Assembled... Going back to finishing slide throttles again now that the casting test is out of the way.
Knocked this up in a half hour this morn, its the pattern for the slide throttle top plate... Spars sanded, notice profile so it will all release from sand, the circles/trumpet stands are tapered too, as are sides of main plate... Sanded and on... First line of spars fitted, these will give the plate great strength when done, as the main body of plate is just 10mm thick... Second line done... And end bits... Superglue applied to all internal corners, it provides a nice radius and takes away the sharp corner that could lock in sand... Nearly done... One or two little bits to fix on yet before I pour, but its 98% of the way there... Im going to cast it this evening... Finished top plate pattern, going to give it a coat of shellac to make it nice and smooth and Im going to hit it with some 710 degree alloy then. The two hooks you see along the top edge are to hold the idle and WOT stops. The 4 little square/pads are something I want to have on there too, They will be the base mounts for the two brackets holding the fuel rail when run in stand-off injector mode. I intend running that mode on my 16v head. Going to pour in a while. The 2 new mould boxes I had to run off, the alloy ones I used doing flange are too short. The bottom mould box does nothing in this case really, its just a flat bed of sand. Ill take a few snaps of filling them anyway. This part is dead easy compared to the flange, because I have designed it in such a way that its all on the top side of mould halves, therefore there will be no parting line on finished item. The mould Prep, I couldnt be bother smashing more pumps as the last one flew and nearly took my head clean off so I chopped up the 2.0l intake instead, Vw would be so proud Notice where they split into 4....hmmmm... They more or less all fit into crucible now... Loaded, Ive worked out that the crucible has to be full to 115mm but I can add more scrap as this melts... Bottom box tamped and raked off flush... Starting to fill top box... Filled... Turned up on its edge to remove pattern... Pattern out, gated, and vented... Laid down onto bottom box again(flat sand surface)...
I forgot to add above, I had to make the lower box wider after that as the gate was very near edge and I was afraid it would burn through timber, that would mean Id have 1/2 litre of molten alloy around my shoes...not good, 5 min had it changed, and the same width as the top box... Away we go again... Lot of smoke in the next few pictures as they are taken as its happening, but there not too bad... I was a bit cheeky not using a riser too, but these will be bored out anyway so the little hollow doesn't bother me. Just to clarify, a riser is like the fill hole, once the mould is filled the riser fills too, you then have two reservoirs of molten alloy to supply part as it cools, alloy shrinks when It cools so it needs to be fed as it does so. I actually thought it would sink deeper on the ones farther away from fill hole but it didn't. These will be bored out but its worth a mention. Things are still extremely hot so forgive the tools all over the place, its way too hot to touch yet... Close-up of stand-off injector bracket platform... One poor pic trying to display its flatness...there'll be more... Should all look pretty 'new' with the kevlar trumpets, not that you'll see them as the carbon fibre plenum will cover them... The throttle stop adjuster brackets turned out in the right place... Small bits of flash to clean up with a small file, gate to grind off, and a few other bits to do to it yet but Im very happy. It should be starting to make sense now...I hope...! Few quick pictures of pistons, I bought these blind on the net, the only thing I knew was that they were 84mm bore which is what I want, thankfully on inspection they have 21mm pins also. I will have to do a bit of machining on these to make them fit in there but not too much. I got them for a song compared to approx 600euro for custom 84mm Vw 8v pistons. They were pretty hard find, I must have looked at around 500 piston sets before I found similar to the 8v style but in 84mms. There'll be a bit of work getting them in there, cc'd and the clearances correct, but its only metal after all Pictures from last nights work, set to work datum machining top plate... I left plate down on a piece of 12x4 teak Ive had for ten yrs, its perfectly flat and conditioned. Under plate there is 2 pieces of .5mm shim steel under one end, and one piece the other end. This is done on the first machining operation with all cast parts in order to get a datum face. The 3 shims ensure the part sits flat, you'll never see a 3 legged stool rock Which is why they have 3 legs. You'll see these 3 datum points cast into a lot of parts if you look hard. Heres an oil pump bottom section, you can see the 3 tabs they used to fix it on when milling the top face...these tabs were cast on, but I just used shim steel underneath as I had a pretty flat surface to go off unlike the oil pump. In the jig, shims underneath plate, I used screws and washers to hold down onto plank, these are out of sight under the guide runners for router... First roughing pass followed by I think 3 more... Finish pass, again taken at .25mm... Laid out and marked positions for stand-off brackets... Pilot bored... Taken out to 5mm, these will be tapped for an M6 allen hex bolt... Plated turned over and 5mm holes countersunk, the plate is now perfectly flat on the top face (checked with 10mm glass and water) so I can now datum machine the bottom face off it... First pass at .25mm shows the slight high spots... Second pass taking off .5mm and the plate is completely surface machined, minimal material removal to get it all surfaced with is good. A small bit of shrink exists on the bottom too under trumpet stands, this will be bored out so its no harm. Combating this shrink is mentioned above earlier. And laid down on bottom plate shows they are 100% true to each other... Im going to pin them together later with some positioning dowels so I can set out Idle hole drillings in both, I can then start tapping holes, etc, Im going to clean up the small bit of mould flash around edges, and bore the two Idle and WOT tabs too. Youll never look at a machined cast part in the same way again Its the very same process In the factories, but with mass production machine and jig lines.
Tapping stand-off bracket holes... Tapped... Pilot boring bottom plate in the marked positions... Laid down on top plate to drill through on 2 end holes... Drilled and pinned... These pins will hold both plates bang on for when Im boring the other 6 holes... Bored... 5mm bit ready for tapping... Tapped... Top plate holes drilled to 6mm and counter-bored... Time to wash off cutting fluid and do a few checks for Idle holes on drawings... I made a great job of washing them ..anyway... Getting there slowly, Idle holes and brake booster vac line to do yet, and stops, and brass throttle plate, and trumpets, and and and..... Onto the Idle drilling's, these are probably the most confusing thing to photo but Ill try and explain how they work, the drilling's are pretty complex and hard to get shots of to show how they work, but anyways...Ill try... All they are is a drilling from the head side(Vac side) of throttle plate(brass, not in the photos) to the top side(atmosphere) side of throttle plate, but half way along this drilling is an adjuster screw to set the amount of air each cylinder gets at tickover. These are to fine tune each port, before I set the overall Idle speed with the main throttle plate stop screw(the two sticky out bits on top plate). They are a by-pass around plate. First, I marked the bottom plate up...keeping drilling's as near to clamping screws as I can, as on second drawing(youll see why later)... This is the line the bit will take, once the main port hole is drilled, the 3mm hole will be entering the side of it, you can see that by the rough scribed circle... Drilled... Next, I had to drill the top plate, same idea, but I had to move these holes slightly to stop them breaking out into the clamp screw counterbores on the top plate, This would mean they would suck air here, no harm, but I want it coming from inside the trumpets. The holes on the lower plate(the first on I drilled) did skim the plate to port counterbores, but this is no harm because these are below the throttle plate, and are airtight because the ptfe strips will be on top of them(Hex allens and counterbores). Ill drilled the port centres too while they were together, drilled from the bottom through the pilot holes, and through the top plate, the way to make sure there all in the right place... Took them apart and drilled the top plate down to meet the main drilling...the hole is offset in respect to the other one to get it as near to the bolt as possible, both drilling's skim each other by half, spot on...you can just see the other hole in the picture... Same with the bottom plate, these holes are opposite so it was just a matter of drilling them to meet... I counterbored the 3mm hole out to 5mm ready for tapping, its around 10mm deep...again you can see the other hole at the bottom meeting it... Tapped with a plug tap(square at end, taps all the way to shoulder) Both plates together again, you can see the holes in the top plate will be plugged with 8mmx3mm plugs(have to cut them yet and epoxy them in) And the bottom holes have the idle adjustment screws in them, these will be grub screws with lock nuts...The tips will be pointed and will meet the 5mm to 3mm counterbore as above... The reason the holes are so close to clamping bolts is because they both meet each other at the join, so I want max clamping force there. A fast pic of how the brake booster line will be, I have to machine out a slot here that will join all ports on the Vac(head) side of throttle plate, Ill fill in the top 1mm of this slot again with a strip of carbon fibre, that way Ill be left with a square slot all the way along. Once the plate is bolted down to flanges, the last 8mm of carbon fibre will be under flanges, so they'll stay there, as well as being epoxied... Ill stop the slot short one end and drill a hole into it for a barbed fitting for brake booster hose, etc...I could link the runners with some hose and tee's, but thats a cat way of doing it. Onto machining the slot for the tab on the brass throttle plate to exit out, this tab will be what the acc cable goes onto, and the return springs... Fixed down in jig...Limit stops either end... Sub base fitted to router... You can just make out bit in there, maybe... First pass... Second, third, finish, the length of this isnt that Import, but has to within a mill or less... Last cut is .25mm below the slots as I want to get a bit of epoxy below the ptfe strip here... Together, roughly...
Tapping stand-off bracket holes... Tapped... Pilot boring bottom plate in the marked positions... Laid down on top plate to drill through on 2 end holes... Drilled and pinned... These pins will hold both plates bang on for when Im boring the other 6 holes... Bored... 5mm bit ready for tapping... Tapped... Top plate holes drilled to 6mm and counter-bored... Time to wash off cutting fluid and do a few checks for Idle holes on drawings... I made a great job of washing them ..anyway... Getting there slowly, Idle holes and brake booster vac line to do yet, and stops, and brass throttle plate, and trumpets, and and and..... Onto the Idle drilling's, these are probably the most confusing thing to photo but Ill try and explain how they work, the drilling's are pretty complex and hard to get shots of to show how they work, but anyways...Ill try... All they are is a drilling from the head side(Vac side) of throttle plate(brass, not in the photos) to the top side(atmosphere) side of throttle plate, but half way along this drilling is an adjuster screw to set the amount of air each cylinder gets at tickover. These are to fine tune each port, before I set the overall Idle speed with the main throttle plate stop screw(the two sticky out bits on top plate). They are a by-pass around plate. First, I marked the bottom plate up...keeping drilling's as near to clamping screws as I can, as on second drawing(youll see why later)... This is the line the bit will take, once the main port hole is drilled, the 3mm hole will be entering the side of it, you can see that by the rough scribed circle... Drilled... Next, I had to drill the top plate, same idea, but I had to move these holes slightly to stop them breaking out into the clamp screw counterbores on the top plate, This would mean they would suck air here, no harm, but I want it coming from inside the trumpets. The holes on the lower plate(the first on I drilled) did skim the plate to port counterbores, but this is no harm because these are below the throttle plate, and are airtight because the ptfe strips will be on top of them(Hex allens and counterbores). Ill drilled the port centres too while they were together, drilled from the bottom through the pilot holes, and through the top plate, the way to make sure there all in the right place... Took them apart and drilled the top plate down to meet the main drilling...the hole is offset in respect to the other one to get it as near to the bolt as possible, both drilling's skim each other by half, spot on...you can just see the other hole in the picture... Same with the bottom plate, these holes are opposite so it was just a matter of drilling them to meet... I counterbored the 3mm hole out to 5mm ready for tapping, its around 10mm deep...again you can see the other hole at the bottom meeting it... Tapped with a plug tap(square at end, taps all the way to shoulder) Both plates together again, you can see the holes in the top plate will be plugged with 8mmx3mm plugs(have to cut them yet and epoxy them in) And the bottom holes have the idle adjustment screws in them, these will be grub screws with lock nuts...The tips will be pointed and will meet the 5mm to 3mm counterbore as above... The reason the holes are so close to clamping bolts is because they both meet each other at the join, so I want max clamping force there. A fast pic of how the brake booster line will be, I have to machine out a slot here that will join all ports on the Vac(head) side of throttle plate, Ill fill in the top 1mm of this slot again with a strip of carbon fibre, that way Ill be left with a square slot all the way along. Once the plate is bolted down to flanges, the last 8mm of carbon fibre will be under flanges, so they'll stay there, as well as being epoxied... Ill stop the slot short one end and drill a hole into it for a barbed fitting for brake booster hose, etc...I could link the runners with some hose and tee's, but thats a cat way of doing it. Onto machining the slot for the tab on the brass throttle plate to exit out, this tab will be what the acc cable goes onto, and the return springs... Fixed down in jig...Limit stops either end... Sub base fitted to router... You can just make out bit in there, maybe... First pass... Second, third, finish, the length of this isnt that Import, but has to within a mill or less... Last cut is .25mm below the slots as I want to get a bit of epoxy below the ptfe strip here... Together, roughly...
Got the tyres on the steels, 185/55/15s I had these tyres on a few Gtis and find them a great size, the 195s tramline a bit more than I like under heavy braking on uneven surfaces. I have done nothing regards the outside of car yet, I have to give it a serious going over paint-wise but thats way down the list of things to do. I hope to fit manual window regs in a while, the duct tape isn't exactly cool. Sitting at the correct height now too, handling has improved 10 fold... New bumpers going on when Ive time... Firestone, I think... I met the lad thats going to bore out the block by chance today and he wants pistons to measure them exactly for when hes boring it, so it looks like Ill have to do the machine work on the pistons tomorrow eve so he can get moving on block. The slide throttles will have to wait for another bit of tampering until tue eve... First batch of piston machining photos, camera only holds 12 pics at a time, I really have to get a bigger card [:^(] You can see the slight different, a bit of machining and crank managery will sort out that... Fixed on my trusty plank... If you can figure out how to jig something and be able to re-jig another part the same size in the same place you can do anything really...the bolt running through pin clamps it down in this case... Two runner bars sized and fitted either side... First few passes to bring down the skirt, it would hit rod if fitted as is, plus, it weighs a ton... Final pass... Jig cleaned out and another one fitted... Oiled up with fluid before final pass... Done, and all 4 done the same... You can just see my machine marks skimming over the rather rough factory marks, I didn't go down lower than the pin area, more-so leveled the rest of the skirt to it... Cleaned up, need to measure up to start machining crowns, want to do this first while I have now a flat surface to datum off(the one I just machined)as I have to do a bit more there yet... More later, I might buy a bigger memory card...
Did some calculations to work out what I had to machine off crown, Im no longer going ahead with the Tdi crank as they're just too hard to get and Im too long looking. So I have a pick of a few Ive here, or are easier obtain... I ran a few numbers as you can see below(If you can read my fantastic 'fast' writing) With the new and old pistons side by side the new ones are 3.2mm taller than the old ones, this means if I fitted them they would stick out above the deck 3.2mm. That wouldn't work as you can Imagine... So I had to get them down to there right place for them to work... The original pistons sit 5 thou below the deck(Im going to call this flush for the time being)with the 2.0l crank fitted which has a stroke of 92.8mm. That means the piston moves down the bore 92.8mm when you give the crank a half turn, TDC, to BDC. 92.8mm is NOT the distance between crank journal centres(bigend and main), but the Diameter of the circle the big end journal centre point makes when turning. I had a look at the 1.8L crank which has a stroke of 86.4mm. This looks good in lowering the piston to deck level or near it. To compare the two I halved 92.8mm = 46.4mm And I halved 86.4mm = 43.2mm. These are the the distances the piston moves up the bore in a quarter turn, which is half the stroke. I took 43.2mm from 46.4mm and I ended up with 3.2mm! This means if I fit the 1.8L crank the piston crown will sit perfectly level with the deck. But there's a problem, On the original piston there is an area called the squish zone, its in the photos below, the squish zone on the piston crown sits .85mm higher than the rest of the crown and in turn .85mm higher than the deck when at TDC. Given the fact that my new pistons sit level with the deck with the 1.8l crank fitted I have to find this extra .85mm somewhere....I cant add it onto piston crown obviously, but I can machine it off the deck. If I machine .85mm off the deck then my new pistons will be sitting .85mm prouder too. This then means Ill have the extra material Ill need for the squish zone. But of course it also means that the whole piston will be proud, whereas the squish zone is only a small area of piston. This should explain why Im machining .85mm off the remaining area of the piston crown in the pictures below in order for everything to work. Doing this will also bring the dome volume in piston to a touch less than the original piston, in turn bumping compression for me too. I haven't measured exactly yet but its just about the what I wanted. How well did these pistons work out for me! While me not fitting the TDi crank is a bit of a shame, Ill be able to rev this higher, and it will also rev faster with the 1.8 crank fitted, simply because the big end has a smaller sweep to cover than the larger 95.5mm TDi crank per revolution=lest distance, less time taken. Ill also have the added torque from the 84mm pistons. The power curve should be pretty nice B) Ive also calculated my new cc to be 1914, which in a way is nice to have it under 2.0l for other reasons. Onto the machining... Piston clamped down again and squared with the front runner... Old piston beside it to show squish zone area. The squish zone is very important, it sits higher than the rest of the crown and goes way nearer the cylinder head face when at TDC, this has the effect of causing turbulence in the cylinder, in turn mixing the charge better, and getting rid of any dead mixture spots before it ignites. It also helps direct the exhaust gas toward port on the exhaust stroke, and therefore aids pulling the fresh mix in the intake port at the point of valve overlap. Setting up... One pass did it... Done all the way across... All done... I filed the step in by hand with a 3mm file, you do not want ANY sharp corners in the combustion chamber, sharp corners don't shed heat as fast as rounded ones and can get far hotter, they also hold carbon, lighting your mix before the spark-plug does, know as pre-ignition. Im sure you've seen older carb'd cars that stay going even if they are turned off, it is the carbon in the chambers lighting the mix. Next, I marked the gas holes in the crowns... Bored, and polished up a bit, Ive to drill the three others tomorrow yet...Hole size is 1mm... There's still swarf in holes that I have to blow out, but Ive more machining to do on underside yet so Ill wait till thats done then Ill tank them... Givin that Im boring the block to 84mm there is a possibility that the bores will flex and wobble at higher rpm, this leads to ring/bore seal breakdown and you loose some of your explosion pressure into the sump, these holes let some of this pressure down and into the area behind the top ring. This has the effect of keeping the top ring pressed out against bore wall at all times and sealed even if there is a small bit of bore wobble. These holes have to be super accurate, one slip and the piston is for the bin... You can see half the hole diameter exiting just in the ring land area,> right behind ring. This hole is just 1mm wide keep in mind, so its hard to get a shot of...! Ill soon be able to get block bored now that I have pistons to give to your man to measure... Finished stripping block this eve ready for boring... To remove the crank pulley bolt while the block is on the stand requires crank to be locked...with one piston out insert bar into bore and other end against the ground, this stops block spinning and stand falling...dont know if this would work with a 3 leg engine stand as I hate them, so dont have one... Wedge crank to block wall... Long lever and a 19mm 12 point socket... Open... Soft wood will barely work doing this, it needs to be hard... Pulled rest of pistons... Intermediate shaft removal, open two 13mm bolts... Prise out under flange with chisel... Removed...keep shaft straight as you remove it... Crank seal off... Flywheel end, depending on your stand you may just have to leave it hang there if you cant remove it... Main caps off... Close up of the famous thrust washers on the centre journal... Pulled out, and left onto cap again... Crank lifted out... Upper shells removed and placed in order on main caps... Time for the squirter's to come out...these spray oil onto the underside of piston crowns to aid cooling... 6mm allen... The squirter's have ball-bearing pressure valves inside, these dont open until the revs exceed 2000rpm, that way you have full oil pressure at start-up and tick-over... Off with crankcase breather...
Lever gently... Remove oil filter, thin nut, and then the oil cooler/heater... Off with the oil filter flange... Out with the vr sender/crank sender... Next, the dipstick tube has to come out... I use an 8mm bit to drive it out... The two head dowels have to be driven down In order for them to bolt on the torque plate...The torque plate is bolted on before they they bore head, its a 3'' thick plate with the 4 bore holes in it a touch bigger than the cylinders, this stresses the block when bolted on the same as it is when the head is bolted on. This ensures the bores are round when the head is torqued down on refitting. The bores actually go out of round once the head bolts are opened, the pull of the head bolts distorts the cylinder once tightened, and back to round again. Thats it stripped...Ill give it a good clean before it goes off to get bored... Got the block clean enough for boring this eve, the heavy stuff is off, Ill have to give it a full once over after it gets bored but its nearly there. I use this gear always, its got built in rust inhibitors and is serious stuff on the cruddy stuff... Oil ways in carriers taped off to keep out the heavy stuff... Started on sump flange and oil pump mount, light spray and a scrub with a brass brush...It really works well Flattening a small bit of corrosion on the outer edge of sump flange... Inside of block sprayed and agitated... And the outsides... Rinsed off in paraffin, blown out, and given a light coat of oil all over...grime gone... Just have to torque up the main caps and off itll go. Ive a nice bit of work to do with block yet, but thats for after it gets bored, and the rough handling is done with...
Got the throttle plate cut out this eve, I had forgotten how nice brass is to work as its been a while, its kinda hard to make a mistake as it files and works so good. Hacksaw is out the window though on brass this thick, so unless your still a student and bound to the hacksaw the jigsaw is the only way to go The plate... Marking Fluid and Marked out... 3mm holes drilled at internal corners... Zip... I cut this rough, to be finished by hand in the vice... Finishing by hand in said vice... Light edge polish all round, drops in there... Height looks good... All edges finished by hand, its the only way to get things perfect I feel... Gave it a quick mop with the dry wheel... Mopped machine finish off lower plate also... Cut up the ptfe strips to 1mm narrower than the tracks... They will be pinned and epoxied on like so to the underside of brass T/plate... Height looks good here also, just enough clearance under plate, ptfe runners will take all the thrust, and not the alloy around ports(Second Pic below)...It slides extremely smooth even half finished... The strips will also run on the inner raised section at the edges, that way the brass plate wont touch the aluminium at the outer edges... End view, this has to be closed off yet, once micro switches are fitted but ya get the idea... Cable and spring tab... Nearly done on the plate, looking forward to doing plenum and trumpets, and the plate to head runners of course. Small update, after a bit of thinking Ive decided to dry sump the engine too for the fun of it, Ive never had a dry sumped engine myself so now is the time while Im at it. I had an idea the lastnite as to how I could build the pump using some Vw parts coupled with some Im gonna make. I feel its such a good idea and fairly simple that I have to go ahead with it. In total the pump will cost 0 as I have the vw bits I need here, its just a matter of re-arranging them around into my own design casing. I have a proper dry sump pump here to give you an idea as to what they are like. Ill be using the pump already fitted in the engine for pressure, and my own pump which Ill be making for the two scavenge pump sections. The pump below has two scavenge sections also, and one pressure section. Mine will have one bank less as Ill be using the intermediate shaft driven pump already in the block for pressure, but instead feeding it from the oil tank via its pick-up inlet. It makes perfect sense and will cost 0 as opposed to 600euro for the pump below(approx). I dont know why I didn't think of this years ago Thats a while off yet though as I want to finish throttle assembly first, but its something to think about also in the mean time.
Update, got the vac line machined, and the plenum surface machined too... I had to machine a slot joining all ports on the Vacuum side of throttle place in order to run the brake booster. I could have done this by linking all runners with a hose and some tees, but thats messy and not the way to do it if you have a clean sheet custom designed part to do. Its easy incorporate it this way. All it is is a groove joining all ports below plate, this groove has a step which Ill fit a strip of carbon fibre to in order to form a square tube. At the end of this tube the lower plate will be drilled in to meet square groove and a barb fitting screwed in. The camera had a massive bit of swarf on the lens that went un-noticed so I had to bin some photos, but most of them are there... Drilled a 12mm start hole for cutters, these cutters cannot plunge cut into alloy, so you plunge them in the open hole and then start moving, they are side cut only. Screwed down... 13mm wide slot cut 1mm deep(Thickness of 5 layers of carbon fibre, thanks to the spoon test!)... And then the 6mm groove routed, its a bit hard make them all out, I stuck in a red line to make it clearer, you can see the step on top where the carbon will sit, and seal it off... Template for the ends, I need to leave a bit on these for mounting the spring brackets, cable brackets ,etc... Done, and I did the same the other end... Next onto the surface that the lip of plelum will sit on, the cast was good enough, but machined is better... The jig in place...always working of the port centre holes as with all the jigs, ensures accurate placement... One pass was enough, round about .60mm deep... Here is where I have to drill in to meet groove, and fit barb fitting... Few other shots... The plans of trumpets, the drawings are a bit busy in spots but you'll get the Idea, these were actually fairly time consuming to draw as there was a lot of things to consider while doing so, they have to fit, be the correct size, have the correct taper, and base size, etc...I need these drawings in order to strike my templates off when making the trumpet form/mould. With these I can check the form at any particular point and ref it off plans. The trumpets will also kiss each other half way up, which is what I want so I can tie them together with a bit of kevlar to stop them vibrating. Due to the plenums design and location Ive curved them towards the opening. Once the plenum is made it'll make sense. I may index each trumpet a bit yet, Ill see how it goes. Ive thought about the former too, I was originally going to make it in one piece, add one layer of kevlar, cut trumpet down one side and remove former(The former hasn't a hope in hell of coming out without something due to shape) and then epoxy up cut in trumpet again and add more layers(1) but I came up with another way where I wont have to cut trumpet. Ill make the former in 4 pieces, a flat bit will form bell mouth that can be screwed off the other 3 parts, The other 3 parts slide together, the centre being a removable core. Once the epoxy is dry, the top flat bit is screwed off, the core is slide out ,and I can then collapse the 2 outers bits together and remove them. (pic below)This is the best way I feel as its easier to take kevlar/carbon direct off a mould as opposed to slide it out/off it. Even if there is a lot of release wax on there, wax breakdown, and its shape may make it Impossible to get off any other way other than cutting. So Im going to tackle all that tomorrow eve. Had a rethink about former with removable core, I was afraid that wouldnt work as any resin that could seep between parts would be a disaster, and Its a chance I cant take, so Ill be adding one layer and slitting down one side to remove one piece core. Ill then add another layer after epoxying join line, Id say 2 layers should be enough, if not Ill add another... Onto the former... A run on the belt sander and its almost there... Checked for diameter at 8 points and hand finished... Making the bell-mouth form... Few rough cuts to get rid of the bulk of material...
Tidied by hand, shape matches template... Screwed together... Checked, and checked again, bang on off drawing when checked with square... Hard to photo right over it... but ya get the idea... Im going to now give it some isopon to blend mouth to body... Very thin skin all over to act as a primer/filler... Also got clay for making the intake runner patterns... One thing that amazes me with this whole build is how cheap these sort of materials are, and what you can make from them... Got it all sanded and sealed... Started with 180 and went all the way to 2000 paper... Waxing...2 coats of shoe polish clear... 2 coats of 5yr old car wax... I went a step further and gave it a coat of ptfe spray just to be sure I cant see how anything could stick to all this! Now I came to cutting the kevlar..... ..... It nearly beat me I have to say....Its Nothing like cutting the carbon fibre, its tough as nails and scissors just dont cut it, or a snips, or a tin shears, or a pinking shears..I had to abandon it all last night as I was just making a mess of fabric trying to cut it, its INSANE stuff and is hard to believe it could be so tough to cut. I had a think and thought the dremel would do it, so I fitted a mini disc I thought that if I layed some hardboard(3mm) either side of cut line with just the width of disc that it would work....well, it didnt, It just pulled up some strands around spindle and jammed the whole lot... I got on the net and had a look for some kevlar scissors, found some, 16 dollars, from the Us, with a ten day delivery time, ad 25 dollars postage...no good, to long to wait. The kevlar scissors looks exactly like a normal scissors, so where's the difference? I played around with the diamond stone until I found out, it didnt take long! All I did was flatten the tops of the blades to give it a more guillotine action, worked perfect, success! You can see the terrible edge on last nights top and bottom trumpet bits, even cutting circles was out of the question...but still, these were two sample bits so Im not worried, I still have my main roll untouched...edges were flayed to provide a good bond where they meet the main tube body section which will be wrapped, as this stuff doesn't like going around complex shapes as the weave doesn't move on itself too good to let it do so and it ends up all puckered...unlike the carbon fibre. Next I cut a long strip off main roll, with the scissors reground it was a breeze... I then teased 3 strands from the edge, this causes it to fray as ya can see below, these should give it good overlapping edge when wrapped, as opposed to just a straight square edge. These will also blend easier and leave less of a step. (Id say/hope)! Thats as far as I got, the scissors was a major problem for a while, but thats sorted now so I hope to resin this up later,
