Heating the spar to loosen hysol ??

[southwind32]

Deleted, sorry

[mr bill]

1100 will melt the aluminum. The lower setting will soften the epoxy.

[jrevens]

Be careful not to overheat the aluminum spar tube. Keep the temperature as low as possible and for as short a time as possible. The 6061-T6 tubes can lose considerable strength, permanently, at temperatures well below the melting point. I think to be safe I wouldn't go over about 400 deg. F for any extended period of time.

[southwind32]

Thanks for the replies...........I was able to remove the fuel tank without using any heat. Frankly I didn't want to take a chance of using heat on the spar, so careful chiseled it away, what a job.

[Guy Buchanan]

For future reference here's a great paper which documents a study of whether aluminum can degrade in high-heat paint ovens. It gives good time / temp / strength plots for 6061-T6 and others:

http://digitalcommons.calpoly.edu/cgi/viewcontent.cgi?article=1132&context=matesp (http://digitalcommons.calpoly.edu/cgi/viewcontent.cgi?article=1132&context=matesp)

And of course, John nailed it. Keeping below 400F for any reasonable period of time should retain all your strength.