Filler prior to powder coating

[MrDerbs]

I have posted the following information on the Welding, Bonding and Fastner board and I am wondering if any of you have an answer for this problem.
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?

 

[boo1]

Have you considered JB Weld epoxy?

 

[PaulRBrown]

Volvo Trucks uses a ureathane sealer for the seems of their truck bodies. The product they used in the 90's was made by Dow Chemical, I believe it was made by their exeter division????not sure of the spelling, anyway, the cabs were being painted usually in 30 minutes or so, and volvo had a warrenty that last 5 years or so...the stuff goes on real smooth also...hope this helps, Paul

 

[PowderCoater]

Yes, there are some great fillers available for use in powder coatings. Some of these are good for up to 1000F! I found a great powder coating site with free info on it at TechnicalHelp4U.com