It is a start...

[trumpy81]

MrBaz, that's looking pretty sweet. I'd be interested in seeing the rest of it when you have finished modelling it. It would be nice if you made it 4 valves per cylinder, just so I could get some feedback on the 4 valve performance as there doesn't seem to be too many people out there building those. It is of course much easier, cheaper, quicker, to build 2 valve heads so that's probably why there are so few 4 valve designs floating around. Just thought I'd throw that in ... lol

How long have you been using Inventor?

Have you tried out stress analysis in Inventor yet?

 

[Dinkum]

This is false as far as I can tell Dinkum. I have two old Triumphs, a 1972 Trophy and a 1976 Bonneville and both run copper head gaskets with aluminium heads and no ill effects.

Also, Top Fuel Dragsters run copper head gaskets and most teams use a VHT product made for copper head gaskets. It's a spray on copper coloured glue for want of a better term. I have some somewhere because I have used it on my Triumphs a few times, but in all honesty it is not really needed on them.

When I crewed for Peter Gratz (Top Doorslammer) he also used copper head gaskets on his aluminium KB block and heads. No ill effects were observed at all on this engine either.

Copper is a fairly inert metal and it takes a long time for copper to corrode under normal atmospheric conditions. It has even been used for roofing in Europe in past centuries.

Hi Andy,

Interesting stuff.

Maybe it's because of the spray on stuff that corrosion doesn't occur - it creates a layer of insulation between the two metals. Have a look here: http://en.wikipedia.org/wiki/Copper_in_architecture#Galvanic_corrosion

Do you use a spray on coating for model engines?

Regards,
Dinkum

 

[AussieJimG]

I run copper head gaskets with aluminium head on my 64 Triumph with no problems

Jim

 

[trumpy81]

Hi Andy,

Interesting stuff.

Maybe it's because of the spray on stuff that corrosion doesn't occur - it creates a layer of insulation between the two metals. Have a look here: http://en.wikipedia.org/wiki/Copper_in_architecture#Galvanic_corrosion

Do you use a spray on coating for model engines?

Regards,
Dinkum

Dinkum, I suspect that if the copper/aluminium surfaces were in contact with an acid (EG: Battery Acid) it would expedite the corrosion process somewhat. Likewise if either were in contact with salt water, but when used as a gasket it doesn't suffer much exposure because there is no way for the air, or anything else, to contaminate it and there is definitely no galvanic reaction between the copper and the cast aluminium.

Another possible reason why the Triumphs don't have any problems is because they use a Positive Ground electrical system.

 

[trumpy81]

I run copper head gaskets with aluminium head on my 64 Triumph with no problems

Jim

Jim, I like the 60's Triumphs, I have a 65 frame that I am going to put the 72 Trophy motor (only usable part left) into and create a bobber if I ever get around to it ... lol

Is yours stock, restored or ???

 

[user 13000]

MrBaz, that's looking pretty sweet. I'd be interested in seeing the rest of it when you have finished modelling it. It would be nice if you made it 4 valves per cylinder, just so I could get some feedback on the 4 valve performance as there doesn't seem to be too many people out there building those. It is of course much easier, cheaper, quicker, to build 2 valve heads so that's probably why there are so few 4 valve designs floating around. Just thought I'd throw that in ... lol

How long have you been using Inventor?

Have you tried out stress analysis in Inventor yet?

4 valves would be interesting, but I'm afraid the valves would just be too small at that point.

I haven't been using Inventor for very long. About a year. I used Solidworks for a little bit before that. This project is helping me learn Inventor as well as other skills. I have not run any stress analysis on anything yet.

Here is an updated rendering showing the niftier milling in the fins for bolt access.

 

[trumpy81]

MrBaz, that's looking really good. I've been using Inventor on/off for about 10 years now. I played with stress analysis once or twice but I'd be lying if I said I understood it all ... lol

If you need any help with Inventor just holler, I'm no expert but I'm willing to help out if you need it.

 

[user 13000]

Sorry I haven't posted anything in a while. I've been busy. I've changed to a 1.5" bore. I've been slowly working on the cylinder head. Here is what I have so far. Don't mind the squareness or thickness. I've got quite a bit of work before it is done. These are just screenshots, not renderings.

15* angle on intake/exhaust ports. Still trying to work out the spark plug angle. I changed from 6 smaller bolts to 4 larger ones to make for easier spaces for spark plugs/ports/etc.

Debating whether to go with a full valve cage, or separate seats/guides/valves.

 

[vederstein]

MrBaz:

You mentioned you're a BSME student. So I assume you're about 20 years of age. I also assume you plan on making these components yourself?

If you're outsourcing them to a shop, then forge ahead. A professional machinist can make these parts. If not, think of the complexity of what you're trying to accomplish.

I too have a BSME (Class of '96) and have been designing machines as a profession for over 15 years. Let me tell you something: it's much much easier to design a part than make it. I'm currently making my 13th engine. It was about after my 6th that I started to get the hang of machining. And my 8th was my first engine from castings (and in any way presentable to show people).

Please don't take this the wrong way, but if you have limited experience with machine tools and you're going to make the parts yourself, I believe your design is too complex. Every detail is a cut, and sometimes a whole different setup. Each time a cut or setup is needed, there is a source of error. Multiply the number of cuts & setups by 12 (for twelve cylinders) and you'll quickly have hundreds of ways to make scrap.

CNC machining certainly helps doing multiple copies if you have CNC availability. Just remember, CNC is like any other computer program: garbage in = garbage out.

Just some food for thought...

Ved...

 

[user 13000]

MrBaz:

You mentioned you're a BSME student. So I assume you're about 20 years of age. I also assume you plan on making these components yourself?

If you're outsourcing them to a shop, then forge ahead. A professional machinist can make these parts. If not, think of the complexity of what you're trying to accomplish.

I too have a BSME (Class of '96) and have been designing machines as a profession for over 15 years. Let me tell you something: it's much much easier to design a part than make it. I'm currently making my 13th engine. It was about after my 6th that I started to get the hang of machining. And my 8th was my first engine from castings (and in any way presentable to show people).

Please don't take this the wrong way, but if you have limited experience with machine tools and you're going to make the parts yourself, I believe your design is too complex. Every detail is a cut, and sometimes a whole different setup. Each time a cut or setup is needed, there is a source of error. Multiply the number of cuts & setups by 12 (for twelve cylinders) and you'll quickly have hundreds of ways to make scrap.

CNC machining certainly helps doing multiple copies if you have CNC availability. Just remember, CNC is like any other computer program: garbage in = garbage out.

Just some food for thought...

Ved...

Understood, but that still doesn't stand a chance holding me back from doing it. I have some machining experience. I'm keeping the design going with machinability in mind. I believe I can make every one of these cuts.

 

[trumpy81]

MrBaz, It's not the cut that's the problem, it's the tolerances involved. Tight tolerances are extremely difficult to obtain even for professional machinists and I can attest to that with my own bumblings ... lol
The plan may call for a 15mm hole for example, but I guarantee that only the best of the best will actually get a 15mm hole. For me, it would be more like 16mm ... lol

The heads are looking good thus far

Wouldn't it be nice if we could use a spark plug exactly the size we need. I'd have 2mm diameter spark plugs everywhere ... lol

Unfortunately, they would be extremely difficult to make at that size

Try offsetting the plug to one side or the other, sometimes you can squeeze it in that way. You can sometimes get away with the plug in a small pocket also.