Epoxi patching vs. weld and grind

[MrDerbs]

We manufacture a custom designed flourescent lighting and which the visual asthetics of the final product are significant. This product is made of aluminum extrusion that is powder coated. To ensure a pleasing asthetic appearance, we currently tig weld the corners of the aluminum extrusion together then spend a considerable amount of time grinding and oscillating to provide a good crisp, clean edge.
In trying to improve our throughput efficiency and we have tried tack welding the inside surface and then filling the outside surface with a putty/bondo type material. The problem that we are finding is the long cure time for the filler or the fact that we may have to handle material twice, once to cure it in the oven and then metal finish and then the 2nd time to powder paint the unit.

Is anyone aware of a material that is fast curing 3-5 hours that can be then metal finished and powder coated after wards? The gaps on the seams we are looking at would be 1/32" max. 3M has said they have nothing that fits this category and I am waiting for a response from Loctite. Any other suggestions?

 

[evelrod]

With words and phrases like "custom designed", "visual asthetics...significant", "To ensure pleasing...appearance",---Stick with what works and continue to produce the quality product you have, presumably, been producing to this point. Just my opinion. My luck with fillers that must be plated is dismal, at BEST!

Rod

 

[patdaly]

What is the maximum temperature the units will see in the Cure oven? I seem to remember the tempurature for Powder coat cure being in the 375-400 F range? If so, I might look at making my own filler with high temp 3-5 min. quick set Epoxy and Aluminum powder. It would take some experimentation with the mix/fill procedure, but unless cure temps are much higher than I remember, it is an avenue I would explore.

 

[bhrescobar]

Have you tryied adhesives like RTV 732 clear? It's not rigid, but works fine in gaps where they have some surface to adhere. Inside gaps they're leak tight, avoid moisture and have a good mechanical strengh. Some dry in less than 10 minutes and may be handled to continue the assembly until they're final cured...