One ring vs two

[CR888]

I was young and stupid......and I broke the law. Being locked up was the best thing that ever happened to me. I left that experience a different person.

That's what we like about the Monkey (not that he been in the locker) but he owns his story, his mistakes & past demons, is a little rough on the outside, has a funky faded tatt but inside is softer with a heart of gold. Helps folks out, is honest, hard working and says it how it is. Poke him with a stick and be an ass you get a taste of the supressed side and eat monkey poo. Black and white no grey.

 

[Moparmyway]

don't do it like this. it will explode

I bet that broke the cast off right where the weld was joined to the crank

 

[jmssaws]

There has to be a way to weld to the crank. Ain't there?

 

[Moparmyway]

There has to be a way to weld to the crank. Ain't there?

Welding cast is a crapshoot, at best.
Especially under high RPM with harmonics and centrifugal forces added, its a recipe for disaster.
There is a reason why they try to add Mallory metal perpendicular to the rotational axis on high RPM crankshafts

 

[mdavlee]

I figure welding cast is about 75/25 on breaking. For ornamental with no movement it's fine.

 

[Moparmyway]

I figure welding cast is about 75/25 on breaking. For ornamental with no movement it's fine.

Ornamental and no moving .......... take your pick : MIG, TIG, stick, heck even oxy welding will hold

I found that if its important, it gets flame-sprayed

 

[mdavlee]

Yep. Yard ornaments tigging with stainless seems to work fine.

 

[Deets066]

So how would one go about building a full circle crank then?

 

[czar800]

I would say that starting with steel or stainless steel would be easier? I'm not a metal guy, but I know there are many different types and grades.

Man I eat a lot popcorn!!
I couldn't find the one of me eating my foot!!!

 

[Mastermind]

I'm fixing to send a 3120 crank off to have it made into a stoker crank.

$600.00

 

[riverrat2]

Would that be a determining factor in which ring you removed (the top or the bottom ring) ?

No

 

[riverrat2]

It would make the area from the "seal/ring" a larger volume. As opposed to the top ring sealing closer to the combustion chamber giving it less volume. Probly such a small amount that you wouldn't notice on a gauge though

I Bet you might be suprized

 

[Moparmyway]

I Bet you might be suprized

Have you tried it, what did you see or find ?

 

[awol]

So how would one go about building a full circle crank then?

Well I don't know how the pros do it, but I started out by chucking up the original crank between centers, and taking a real light cut all the way around to true it up. I then took measurements and ordered crank saver sleeves of the same dimension, fitted them on the crank, and filled the voids with jb weld. After it hardened I had to chuck it back up and do some cleanup. It looks kinda ruff but works ok. This was my first, and I have another that needs done now.

 

[polkat]

I have thought at one time to have the other half machined out of aluminum and have a keyway cut on both sides drill and tap and a lot of good locktite and giver. Still think about it every once in a while

 

[jmssaws]

Well I don't know how the pros do it, but I started out by chucking up the original crank between centers, and taking a real light cut all the way around to true it up. I then took measurements and ordered crank saver sleeves of the same dimension, fitted them on the crank, and filled the voids with jb weld. After it hardened I had to chuck it back up and do some cleanup. It looks kinda ruff but works ok. This was my first, and I have another that needs done now.

View attachment 7869

When can I send you one?

 

[awol]

Anytime man, but uh, when were you wanting it back?!

 

[jmssaws]

Anytime man, but uh, when were you wanting it back?!

Whenever I get it back will be fine.

 

[tree monkey]

Well I don't know how the pros do it, but I started out by chucking up the original crank between centers, and taking a real light cut all the way around to true it up. I then took measurements and ordered crank saver sleeves of the same dimension, fitted them on the crank, and filled the voids with jb weld. After it hardened I had to chuck it back up and do some cleanup. It looks kinda ruff but works ok. This was my first, and I have another that needs done now.

View attachment 7869

that's basically how I do mine. did you need to in large the case for clearance?

 

[awol]

that's basically how I do mine. did you need to in large the case for clearance?

No, but the clearance was less than the original. The crank saver rings are real thin, probably about .020".

Whenever I get it back will be fine.

Give me a call anytime if ya want.