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gunsmith
04-26-2003, 08:06 PM
I am considering the purchase of a spray welder for my shop. I do a lot of shaft rebuilding, stainless and otherwise. Can you spray on a surface that when you approach near the original metal the new surface will stay in place? Do you have to pre machine to get a uniform surface? Any experience on different brands of equipment? Believe it or not, I can't get these questions answered by the people who sell the equipment but there willing to sell it.

BC21OSH
04-26-2003, 10:12 PM
The only experience I have is watching it being done but they had to turn the shaft down some and actually rough it up to provide a surface to hold the flame spray and assure that the build up was thick enough to hold up. The sprayed surface was rough afterward and was then machined down to nominal again. The brand I believe was Eutectic but don't quote me on that,it has been quite a number of years now.
You don't want to do this on a good lathe though. It is pretty hard on the equipment.

Bernard

Thrud
04-26-2003, 10:41 PM
gunsmith:
make sure the surface is clean and dryto avoid contamination and poor adhesion. A plasma torch version works best. You will need to experiment - on scrap to get the hangof it before commiting to the actual job. TIG welding Aluminum is as difficult as proper spray welding.

Good luck.

Rick B
04-27-2003, 11:38 AM
I have used a Metron oxy/act powder spray gun and a Metron arc wire feed gun.With both you under cut the shaft and make a rough cut or fine thread for the spray to stick to.The arc spray goes on alot faster but the noise level is real high and you need a welder with a high dutie cycle and a good air compressor to keep up.You can spray stainless,chrome moly, and even ceramics. All in all it seems to work well once you get ahead on the learning curve.