Teardrops n Tiny Travel Trailers

I have been putting-off annealing my aluminum trim so I could get a compound bend. I remembered a little trick that helps let you know when you've reached the right temperature instead of watching for an orange flame.
If this is old news forgive me, but I didn't see it when I searched the archive, though I might have just skimmed over it.

I am using 1/16" thick 1/2"x1/2" aluminum angle frome Lowes. Light an ordinary candle and run the flame under the aluminum to lay an even coat of soot on the surface. Then use your propane torch to heat the aluminum just until the soot disappears, then let cool. I did it tonight and the angles bend like butter. I was pleased with the results.

Now, get back to work.

Mark

Is it really that easy? I'm not to that point yet, but have been dreading it because I'm afraid it'll be the kinda thing that takes alot of practice to do exactly right.

Mark,
What do you mean by saying that the soot disappears? Does the aluminum turn black, or does the soot go away?

The soot will actually go away. You will also start to see the orange flame about the same time.

TIP: Do not put too much soot, just enough to discolor the aluminum.

This method was used to anneal the wing-spar tips for a homebuilt aircraft. It was not my idea. Just something I read about and tried.

Mark

my progress photos are at:

photos.yahoo.com/westok03

Tempilstik temperature indicator crayons evidentally work well too. You just mark the aluminum with the crayons and they melt within 1% of their rated temperatures. I can't remember the correct crayon melt temperature for the aluminum trim, but the following website goes into a pretty detailed description of annealing aluminum: http://www.tinmantech.com/html/aluminum ... inued.html . Scroll down the page and you'll see the bit on using the Tempilstik crayons. The site is geared mostly toward working with sheet aluminum for airplane bodies, but it is pretty interesting. I picked up a tempilstik at my local welding shop, and I plan to use it to anneal some aluminum bar stock for the standards of a large format camera I am building. I haven't used it yet, but I understand that they work pretty well. I'll let everyone know how it goes once I have used it.
Amy

I DVRd "Black Sky" last night and watched it today. It is a Discovery channel show about the Rutan X-Prize attempt. They used the wax that Amy was talking about on leading edges to find out what kind of tempratures the ship experienced.

Went fishing this weekend and in addition to the Red Drum and Spanish Mackrel, I also caught a cold. So all I've been doing is catching up on the TV I missed this weekend.

I haven't had a chance to use the tempilstik yet, since I have been busy with home remodeling. I took a look at it the other day, and I have one rated for 650 degrees F. I am not certain if that would be the correct one for the aluminum angle, but that is the correct temperature for the barstock that I have. I am assuming that it is probably the right temp for the angle as well. I'll see if I can find a little time this weekend to test it.
Amy