Iain T
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Posts posted by Iain T
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It's not unheard of to skimp on tooling for parts that are not on show, perhaps this is one. I remember one story told to me by an engineer at GKN Telford, who was charged with making a front crossmember assembly for a Toyota car. This was dual sourced in both Japan and UK. On looking at the Japanese part there was bad rippling and material almost doubled up at one area. On pointing this out to his Japanese counterpart the Japanese said it's underbody so functionality and durability is more important than looks. As long as the mounting points are within tolerance and it passes all long term durability tests all is acceptable. That argument didn't hold water with Ford Transit crossmember who wanted everything within tolerance. We made both sets of prototypes for GKN and the pressings were very difficult due to the shape and specified high tensile materials plus when the parts were welded together the heat caused the parts to distort so to compensate we distorted the tack welded assembly by 3mm in the centre with hydraulic clamps. All good fun, I used to and still love sheet metal engineering.
Iain
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More bad or very worn tooling. Rippling mainly occurs where there is a severe change of shape and/or the material is uncontrolled. As you can see in Ian's panel the length of line from one side to opposite side is much longer at the front and back than in the middle where the excess metal rippling occurs. In Colin's panel again change of shape but at the end of the panel so it should be more controlled by the blankholder. It's probably worn or aftermarket tooling. The problem with rippling or in extreme cases doubling over of material is it damages the tooling and also stops the tool from bottoming out so the rest of the panel is ill defined.
Had a look at my panels and there aren't a lot of ripples. I can't believe the original tooling is about so all new panels must be stamped from aftermarket tooling.
Iain
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Seems like a replacement part as I think original Triumph parts would not have the rippling. The Triumph part would have been pressed using a 3 piece draw tool ie punch, die (top tool) and blank holder. The cushion pins push the blank holder up, the flat steel sheet placed on the top and the press cycled. The top tool comes down clamps the sheet to the blank holder and stretches it over the punch. However the variations of lumps and depressions and where they are located in the components form can make life very difficult. How to achieve an unrippled part is all down to controlling how the sheet flows and how to do so involves a lot of technology and no small measure of 'black art' and experience.
I can only assume this was made on aftermarket tooling.
Hope this helps...I love press tools😍
Iain
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I would have thought your driveline angles are OK, you just need to centralise the back of the 'box by spacing the front mount.
You can then get on with assembling the rest of the car!
Have fun
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Chris,
Most people think uj's will take care of any driveline angles. The opposite is very much the case, it is imperative the input and output angles in top and side views are parallel ideally to +/- 3 degrees max. Much more and vibration can make the car undriveable.
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John, the plasticine was only to check clearances. We did 'plastic coat' some tools using a rough cast kirksite base for strength. Ciba Geigy 219 with 'flexidiser' was the preferred coating as it was durable and crack resistant. Speed is of the essence with automotive prototypes and we managed to get down to just under 6 months to tool up a complete car Body in White from a phased cad data release. The Japanese were down to 3 months, industrious little buggers, but they have almost limitless manufacturing capacity.
I do sort of miss the wide eyed panic and time penalty scares, it made everyone pull together and help to a common mission, a bit like Covid.
Iain
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We used to use the plasticine trick on prototype press tools. We used kirksite which is a zinc/aluminium alloy for proto body panel tools (quicker to cast as much lower melting point) and never had enough time to finish the tools so plasticine and some brave guy climbs in the tool with a die grinder! Yes we always used big stays just in case the mechanical press overcranked or a hydraulic press creeped down....you only make one mistake!
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Bloody union with olive leaked as I couldn't get a straight spanner on it. Gave up and made this from 6mm steel. Bear in mind I was at my old works so verticle bandsaw and press brake makes short work!
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Sorry dunno what went on there the homemade spanner is to fit the nut at the front end of the heater return pipe. Works if you have a tubular manifold.
Iain
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Plasticine, playdough is good for measuring clearances on say bonnet to rocker. Put a small thin verticle dob on the rocker and a small smear of oil on the top (stops bonnet from sticking). Carefully close bonnet and it will squish the plasticine. Raise bonnet and measure thickness of plasticine...hey presto you have your clearance! Make sure the plasticine is soft and only use a small piece or you can dent your bonnet!
Iain
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Plasticine, playdough is good for measuring clearances on say bonnet to rocker. Put a small thin verticle dob on the rocker and a small smear of oil on the top (stops bonnet from sticking). Carefully close bonnet and it will squish the plasticine. Raise bonnet and measure thickness of plasticine...hey presto you have your clearance! Make sure the plasticine is soft and only use a small piece or you can dent your bonnet!
Iain
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Sorry all for some reason I couldn't see some of the replies. John's logic, as usual, seems correct! I'll go for the crank breather filter route and let the PCV do its job.
Iain
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Aah but I have a Vitesse, surely air can be sucked in via the new crankcase breather to the inlet manifold thereby weakening the mixture. Or does the PCV prevent this? But then I am trying to prevent crankcase pressure (most of which is created by blowby?) so is air ever sucked in via the crankcase?
Too many questions to which I don't know the answers🤔. I have a crankcase breather filter but don't want to to fit it and cause further problems.
Cheers
Iain
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A question for the technical guru's:-
If a crankcase atmospheric breather with filter is installed and the original PCV kept won't this draw air into the crank and thereby weaken the fuel mixture at higher revs?
Iain
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Thanks Nigel, I'll take a video when I go in next Tuesday!
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After many hiccups and more ordered parts I finally fired up the engine today!!!😃
I cranked the engine to prime the oil system, put the plugs in and much to my surprise it started second pull.....Yeh!
Downside is the thermostat housing spring a leak which needed grinding and lapping as it didn't fit at all well. I also replaced the engine mounts and need to order a longer vacuum tube for the dizzy/carb. Just tweaking and refitting bonnet assembly then test run round the block to see what falls off!
Can't wait to actually give it a few runs, I'm still crossing my fingers for VSCC Prescott on 2-3 August.
Thanks everyone
Iain
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Agreed it shouldn't be left it must be corrected or it will cause mount failures. Perhaps this misalignment is what caused the gearbox mount to fail?
Can you see if the engine plate is bent? To give this deviation I would have thought it would be visible. Can you put a straight edge on it? Apart from going back to the chassis or straightening the front plate I would have thought an engine bracket spacer would be the easiest way to fix the problem.
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I'm not familiar with how the mounting bracket is attached to the engine, I assume from the posts it's through the front engine plate unlike my vitesse which are to the block. I hate to suggest it but as a bodge can you put a spacer(s) between the plate and bracket to give enough adjustment to centralise the gearbox. Well not so much a bodge as a pragmatic engineering solution!
Iain
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Sorry, yes I wouldn't bother taking prop off for now. You may need to eat a couple of Weetabix or support the engine with a lift or hoist!
Iain
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Yep you got it it's that adjustment slot.
I suggest releasing the offside and see if you can push gearbox round to centre on its mounts. Hopefully the offside is also to the front of the slot so it can swing round.
Let us know if it works!
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If your bracket is like this, as I said you will/should be able to loosen and pull the gearbox round to centralise in its mountings. This should solve your problem if as you say you haven't touched the diff.
As you say it may well have been off centre when you took it off but best to centralise it now to take any tension off the mounts.
Iain
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I wouldn't worry too much about why won't it go back in the same as it came out just focus on where you are now. Unless you have mucked around with the chassis there can't be anything serious wrong so it's just adjustment. Just fitted my engine/gearbox and been through this!
I think there is a horizontal slot in the mounting bracket, support the engine undo the nut and see if you can swing the engine/gearbox round. It's surprising how much it can move (as YS said). I let the engine/gearbox rest on the mounts and gave it a good shake to settle before tightening the nuts.
Hope this works.
Iain
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Peter's right something very wrong, it does sound as though there is no fuel to the carb. What about checking the fuel line to the carb, is anything getting through?
Iain
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Thanks for replies. My Huco is on two cotton reels fixed to a flat blanking plate where the old pump was. To get enough room to fit a right angle breather pipe outlet I'll make new Zed section blank plate to move the Huco out of the way then route as per Clive's post with a catch tank.
After spending time money and effort to build a hopefully strong engine I want it as oil leak free as possible.
Thanks again
Iain
Vitesse bonnet lower aperture
in Bodywork & Fittings
Posted
Adrian,
Good job well done. It looks good and structurally sound.
Iain