Alternatives to Metal Casting: Try Metal Repair Compound

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Metal repair compounds are considered a viable alternative to traditional metal casting, especially for small batch work. However, there are concerns about their effectiveness, with comparisons drawn to JB Weld, which is noted for its reliability but requires careful application to avoid air pockets. Users have reported issues with adhesion and durability, particularly in high-stress applications, suggesting that these compounds may be more suitable for temporary fixes rather than permanent repairs. The importance of surface preparation is emphasized, as proper cleaning and roughening can significantly impact the bond strength. Overall, while metal repair compounds can be useful for quick repairs, their long-term reliability in demanding environments remains questionable.
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If this stuff is so good why not use it instead of casting ?

http://www.alibaba.com/catalog/10408794/Metal_Repair_Compound.html

For small batch work, it seems ideal, i have seen other products that claim
to be equal to this, ie one that repairs stainless steel, even shafts, there
must be some (hype) in the claimed properties of these products ?
 
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It would appear to be essentially the same as JB Weld, without the mixing requirement. If so, then it's not nearly as easy to work with as they'd have you believe. Patching something with JB involves a lot of effort to make sure there aren't air pockets or other gaps. I've also found that, contrary to the advertising, it's not prone to accept drilling, tapping, filing etc. without crumbling.
 
Its not the same as JB Weld, different viscosity. Sure there's marketing hype, and the MSDS has plenty of haz warnings, and you really should check out its hardness/abrasion resistance before buying too far into the hype.

JB Weld has worked well for me, drilled and tapped before but it was an encapsulated patch so it kept the material completely in compression during those operations. Great stuff, not many other ways to patch stuff, its like duct tape that lasts longer... :smile:
 
I imagine Lab Weld could be used for supeficial repairs, but in high stress or fatigue susceptible applications, I doubt it would be satisfactory.

I can't imagine repair a pump shaft for example.

It all comes down the service environment.
 
Cliff_J said:
JB Weld has worked well for me
Me too, in many applications. It's possible that I didn't mix the bad batches as well as I should have, or got too much skin oil in them while kneading. Besides the crumbling under tool use, I've had some that absolutely refused to stick to the material that I was trying to repair (and it wasn't anything exotic).
 
Probably good enough for quick and dirty patching/repairs, usually temporary. Keeps you going 'til new part arrives.
Personally I like the epoxy putty, various brands. Just cut what you need off, knead it and shape it. I've used it for holes in panels mostly. Recently used it to repair a valve and the worn end of a pump impeller. Both seem to be doing well.
Danger: Hint, clean the surface really well. Then slightly roughen and clean again. Leave no oil, rust or emery behind.
 
Thanks for the tip, Kleinjahr. I do tend to be a bit lazy when it comes to cleaning stuff. :redface:
 
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