Rhinodriver Posted September 6 Share Posted September 6 Has anyone had success finding someone to repair a pot metal part? My gearshift control lower support broke and the machine shop I normally go to said they could not weld or braze it because of the nature of the metal. Otherwise, I guess I'm headed to local junk yards Link to comment Share on other sites More sharing options...
ArticiferTom Posted September 6 Share Posted September 6 Have one cast in aluminum or brass and finished by shop . If it broke once it is weak and will only break again . 2 Link to comment Share on other sites More sharing options...
Bloo Posted September 6 Share Posted September 6 I think a replacement from another car is going to be cheapest by far. What year? Link to comment Share on other sites More sharing options...
Rhinodriver Posted September 9 Author Share Posted September 9 It's a '47 Torpedo 1 Link to comment Share on other sites More sharing options...
Gary_Ash Posted September 12 Share Posted September 12 Frequently, I’d say to glue it together, fill the drilled holes with wood filler or wax, then dip it in melted paraffin a couple of times to build up the dimensions by about 1.5%, and take it to an aluminum sand casting foundry. The wax will make up for the casting shrinkage. The problem with this part is the larger hole for the bushing which would require a core to be made and changes to the pattern. Could be done, though. Alternatively, fill the bushing hole completely, as well, and bore the part after casting. The curved surface on the bottom where it fits the steering column also complicates the making of the sand mold a little. Alternatively, draw it up in a CAD program and have it 3D printed in steel/bronze alloy by i.materials.com. You can leave the holes in the CAD model, just a little undersize so light finish machining is all that is required. It’s always a good idea to put a ruler next to the part when taking photos so that dimensions can be approximated. 2 Link to comment Share on other sites More sharing options...
Gary_Ash Posted September 13 Share Posted September 13 I thought about this a bit more, made a trial CAD drawing with guesses at dimensions. I assumed the steering column was 1.75 inch dia. and the shift tube was 1 inch dia. I loaded the .STL version of the CAD file onto i.materialise.com and got a price of $474 for a part in bronze-infused stainless steel, tumble polished. It would still need some finish machining. Seems pricey to me. I don't think any of the 3D printed plastics want to live too near engine heat. My conclusion is that a casting pattern could be printed in very cheap PLA plastic and used to sand cast an aluminum part. Investment casting would be better as no core required. Finish machining would still be required. Actually, this is not much different than gluing the old part together and dipping it in wax. A short piece of wood dowel inserted through the bushing would form a nest for a core in the sand. A simple core box can be used to make a round core for the large hole. There is currently in progress another "lost PLA" investment casting project for antique car parts going on at Hildebran Designs in NH. They quoted very reasonable prices for making some parts. See https://www.hildebrandesigns.com/ Front view Rear view 2 Link to comment Share on other sites More sharing options...
PONTIAC1953 Posted September 16 Share Posted September 16 are you sure this isn't cast iron ? Link to comment Share on other sites More sharing options...
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