[chrispare]

hi is there anyone in ontario that may be intrested in helping me out.
I have a cad drawing (solidworks) of a crank that is for an engine i am working on.

i was hopeing that someone may like to help me out by turning one??

chris

[stevehuckss396]

How Large is this crankshaft?

[chrispare]

it is about 160mm long, and about 40mm diameter.
Is for an 8cl that ive been working on.

chris

[dynosor]

it is about 16mm long, and about 40mm diameter.
Is for an 8cl that ive been working on.

chris

You guys use the metric system in Canada, right? Which aspects are 16 mm long and 40 mm in diameter?

[DareBee]

we work no different than you (US).
Most of the automotive and aerospace stuff is metric but in the real world we design build and measure Imperial.
It is kinda funny because I knew nothing of inches until I hit shop classes when I was 14 and have converted everything to inches ever since.

[chrispare]

ok the file is in inches i believe.
so .627in wide and 6in long.

my other post was 160mm long

[dynosor]

Maybe this guy can help you: [ame="http://www.youtube.com/watch?v=rPijP32prJs&feature=related"]YouTube- 9 pin crankshaft M100[/ame]

[chrispare]

i think that is a bit big.
the crank i want is only 6 inches long.
so any intrest.

[stevehuckss396]

i think that is a bit big.
the crank i want is only 6 inches long.
so any intrest.

Don't you have a lathe? If you do, you should be able to make your own. There is an enormous amout of time involved in a crankshaft. You can buy a small lathe for 500USD. See if you can find one of these local for you.

http://www.harborfreight.com/cpi/cta...emnumber=93212

With the amount of work involved, I would think it will be tough to find someone to make you one. I made a V4 crank and spent about 12-15 hours on it.

[dynosor]

With the amount of work involved, I would think it will be tough to find someone to make you one. I made a V4 crank and spent about 12-15 hours on it.

Yes Chris, the reason you are not getting much response to your offer is because you have effectively asked for a $2000+ donation for nothing in return. Steve is a very experienced builder and able to finish a crank in 15 hours. The rest of us could easily take two or more times as long without achieving the required quality level.

When designing an engine of a given size you should bear in mind that large parts require a lot of material removal and this takes time, while small parts spring easily and have to be cut lightly and this takes a lot of time. Small parts require finer tolerances than larger parts and are therefore harder to make.

What this really means is that you should design your engine as if you are going to build it yourself. This involves repeating the question "how am I going to do that?" for every aspect and finding a resonable answer before locking in the design.

[chrispare]

ok any advice,on turning my own.

[stevehuckss396]

ok any advice,on turning my own.

If you have a lathe, you could start with a piece of square stock and centerdrill the 5 centers on each end that will be needed. Then I turn the OD down slowly checking and adjusting the tail stock until the size from end to end is within .0005 or less. Then after the OD is cut, start from the tailstock and work toward the headstock. As you finish the crank throws, insert a spacer to keep the gap from closing as you tighten the tail stock. The square ends will also help to index the shaft when milling the counter weights.