Suggestions for a foundry, one off casting.

[dohenyboy]

What are the critical dimensions?
You have a casting here that was designed for mass production. There is no excess metal on it. For big production runs, it is worth it to make the casting more complicated to save metal.
However, for you, you could simplify the casting and make it something that is easier to cast.
Or could be machined out of a solid piece.

[ti325v]

Hi Guys:
So far I have three off the cuff estimates for CNC from $3,500 to $6,500 for a one off.
Wow !
I think I will be using the piece off the other engine I have, very lucky it is exposed and easy to remove and install.
One $3500 piece on a $2,200 engine.....cannot go there.
The engine is now pulled apart except for the crank, which we may leave in place.
I think it never had to come apart, but since we are in there, I will replace 2 pistons and possibly the liners, hone, and re-ring it. There is some scoring on one cylinder wall, and another looks like it suffered some sort of very small seizure, they is some scuffing on the liner. I think this one will run till I die.
Thanks for all of your suggestions and support.

[ti325v]

Originally Posted by dohenyboy

What are the critical dimensions?
You have a casting here that was designed for mass production. There is no excess metal on it. For big production runs, it is worth it to make the casting more complicated to save metal.
However, for you, you could simplify the casting and make it something that is easier to cast.
Or could be machined out of a solid piece.

Hello, yes you are correct and obviously have some knowledge in this field.
It would be much easier to cast or machine it with out all of the factory reliefs in it.
Great idea. Thanks for the suggestion, but in any case, it will likely be more then I want to pay, and with a spare part here I think I will use what I have.
Thank you.

[hellosailor]

ti-
Plasma spraying is indeed "structural" it bonds new metal into the old, with a choice of new metals. However it is usually used to rebuild very small layers of metal, i.e. to add metal to a worn roller shaft, which can then be lathed back into tolerance. A couple of mils, perhaps a couple of millimeters, but that's all it is normally used for AFAIK. Anything more than that would be conventional welding, much faster and cheaper for laying up new metal on an old part.

If there is a university with an engineering school anywhere near you, they may know local artisans or hobbyists who can do a one-off sand casting for a new part. There is a lot of interest in metal work on a less-than-commercial level, and often either their art department or engineering department may know who is doing this locally.

[ti325v]

Hi Sailor:
Sorry I used the wrong term, of course it is structural.
My intention was to say that pretty much exactly what you said, in that in goes down in layers that are very thin. I was concerned about how much build up we would have to do, and the possibilities of failure with so many layers and the weight and vibration of the oil filters hanging of the part. It does have the be solid.
I know nothing of the properties spraying, but I fear delamination.

I need to build up as much as 3/16th of an inch on all of one side of a part that is 18 inches long, and six inches wide, and as little as 1/16 thick.
I do not believe this could be successfully welded here, I have never seen any weld pre heated, even on cast iron, I doubt there is a welder skilled enough on the island not to blow it full of holes. I have found that having it made one off CNC is very expensive.
To my amazement I HAVE found a foundry man who worked here for the french 50 years ago, (Vietnam) and he has the skills and knowledge to remake the part in a quility fashion. I have seen his work, looks nice.
Best part....I expect it to cost less then $150 with all machine work! Rarely are there real wins here in Vietnam, I think I have found one.
Thanks for your input.

[bornyesterday]

You're welcome.