Chevy V8 Scale Engine Plane
- Thread starter TrashCo
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Valves are made from 1/4" drill rod (silver steel for the UK). You can get it from most metal suppliers including Hobby Metal Kits.
Thanks for that so drill rod and silver steel are alike then . is that hard enough , sorry all new to this
Yes, it's hard enough. You can always heat treat it to improve the hardness but the plans don't call for it.
thanks , do I make the Valve cages out of the same ,
Drawings show the material. Valve cages are brass.
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Sorry I did not find that on my drawings , thanks for heads ups
Material type is typically in the bottom of the title block in the lower right corner of the drawings or noted next to the part. Looks like the material was not noted for the valve cages.
A word of advice. Ream the .250 holes in the head for the valve cages. Be sure to make the indicated hole depth or a slight bit deeper. Make the valve cages .0005 to .0015 larger than the reamed hole and be careful with the length of the large diameter of the valve cage. I neglected to ream my holes and my setup didn't accuately repeat hole depths or the length of the valve cages which created the problems I am now having with the valves sitting proud. There is only .017 clearance between the valve and the piston at top dead center so the valves need to be as close to flush as you can make them.
Also, set the lathe compound to 45 degrees and cut both the seats on the valves and the valve cages. Don't move the compound until you have all the valves and cages done. That way you are guaranteed to have the same angle on both. I cut the valve seats with the valve stem in a collet and the lathe running in reverse with the tool upside down.
A word of advice. Ream the .250 holes in the head for the valve cages. Be sure to make the indicated hole depth or a slight bit deeper. Make the valve cages .0005 to .0015 larger than the reamed hole and be careful with the length of the large diameter of the valve cage. I neglected to ream my holes and my setup didn't accuately repeat hole depths or the length of the valve cages which created the problems I am now having with the valves sitting proud. There is only .017 clearance between the valve and the piston at top dead center so the valves need to be as close to flush as you can make them.
Also, set the lathe compound to 45 degrees and cut both the seats on the valves and the valve cages. Don't move the compound until you have all the valves and cages done. That way you are guaranteed to have the same angle on both. I cut the valve seats with the valve stem in a collet and the lathe running in reverse with the tool upside down.
Bicycle spokes are 2mm approx 0.080" and are straight, either s steel or almost spring quality steel.
Look at the bottom right corner of the page. Material will be in the box. If there is something on that page NOT made out of that material it will have a note on the page near that part.
Valves are drill rod
Cages are Brass
Push rods are drill rod but you could also use "music" or "spring" wire
Valves are drill rod
Cages are Brass
Push rods are drill rod but you could also use "music" or "spring" wire
peter smith
Member
I have built a few engines this one I built in the last 6 months, all made from drawings I have purchased from various places, some valves I have made from stainless and some from EN 24. I machine them as the picture using tailstock. m/c it to long then saw off the centre end, then make a small collet so you can face it to length and m/c the groove. I make push rods from piano wire available from model shops.
I have had very good success with this method, hope this helps you. If I can give you any more advise I will do my best.
Cheers Pete.
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timing pointer now done
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I did notice that yours is going to be a little heavier than the original one.
I have not yet trimmed the sides of the block. I will do so after all the other machining is finished. I have not drilled through for the cam and crank and will not do so until I build those two. My test pieces for the crank have not gone well but I used aluminum. I'm going to practice again with 12L14 and see if that goes better. I only have manual machines so my progress is a bit slow.
I was referring to the step in the face I've circled; the area that is machined out of the flat between the lifter galleries. I only noticed it because I'm at the stage of machining that area on mine and was trying to figure out where that step should be. It is sort of a result of the machining of the 2 lifter gallery areas. I don't think it is a functional surface, so it probably doesn't matter where that step is. I modelled up the block in Autodesk Inventor to get a better idea of how all the machining should look.
Thank you very much for your postings and pictures. It really helps a lot. I found that I needed to model things up (especially the heads and intake) as it is hard to figure out from the drawings exactly what they look like. And this is from someone with almost 40 years of designing precision components!
It is this area I was referring to:
Thank you very much for your postings and pictures. It really helps a lot. I found that I needed to model things up (especially the heads and intake) as it is hard to figure out from the drawings exactly what they look like. And this is from someone with almost 40 years of designing precision components!
It is this area I was referring to:
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Thanks, I see it now. Looks like I missed that feature when I milled the top of the lifter valley. What I missed is the .375 offset of the lifter valley from the front of the block shown on page 4. I'll pick it up when I drill for the distributor.
What do you think of using PEEK for the spark plug insulators? Corian is pretty much impossible to find, especially with many businesses closed these days. So I bought a piece of PEEK. It is not expensive for the size needed here ($6 from McMaster-Carr for more than enough). I broke the first attempt, but the second one worked well. Easy to machine, slightly flexible. It is supposed to be good to temperatures higher than Corian can take. So I've made one spark plug....not perfect, but I'm pretty happy with it. I'd hate to make 7 more only to find out later that I shouldn't have used it.
One other question. What should the gap be for the spark plug? The plans use the tolerance of all the pieces to end up with a gap, but in case I've got things off a little, I can bend the outer electrode to adjust it. I suppose I can go through the plans and assume everything is dead-on and see what the gap should be, but how critical is it with the ignition system it uses?
thank you,
Rick
One other question. What should the gap be for the spark plug? The plans use the tolerance of all the pieces to end up with a gap, but in case I've got things off a little, I can bend the outer electrode to adjust it. I suppose I can go through the plans and assume everything is dead-on and see what the gap should be, but how critical is it with the ignition system it uses?
thank you,
Rick
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You can use anything you want to make them. Your model! What ever you make them out of, gap them at .015
Thank you Steve for the quick reply. I just didn't want to hear "whatever you do, don't use PEEK!".
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