Aluminum Repair

[luv2fish62]

Hi all...I am repairing a couple of small holes in an aluminum hull and came across a product called HTS-2000. It is like a welding rod but uses MAPP gas to heat the metal and you use the rod like it was soldier. The web site makes it sound like the greatest thing since sliced bread but wonder if anybody out there has used it or has a recommendation. Thanks.

 

[dingbat]

Re: Aluminum Repair

They had a booth at one of the outdoors shows I attended over the winter.

As a certifed welder, I as sceptical and asked if I could give it a try. Granted they had thin material, even welded two aluminum beverage cans togheter, but I must admit, I was impressed with the ease and the results.

I wouldn't dream of using them in a strucutural application but I don't see why it wouldn't work for fixing a couple of small holes in the bottom

 

[Bob_VT]

Re: Aluminum Repair

Be very very careful......... aluminum melts FAST even with a propane torch

I would not recommend it at all

 

[RIDEPATE]

Re: Aluminum Repair

I've tried those, yes very thin, i.e beer cans, they work, but for anything thicker than .010 I could not get the material to stick. JB Weld works great as long as the surface is prepped well. I choose it over any low-heat Al. rod.

 

[JB]

Re: Aluminum Repair

Not a welding rod. More like silver solder or brazing rod. It melts at lower temp than the aluminum. Not as strong as aluminum, but does a nice job with MAPP. I have even used it with propane after a lot of profanity. For structural strength I have used it in combination with pop rivets.

It has been around for many years yet still gets attention as something "NEW!!"

 

[fishrdan]

Re: Aluminum Repair

If you are repairing small holes, find something other than the aluminum brazing rods. I have used then too, and they worked OK for what I did, but... They melt at almost the same temp as aluminum, so you have to regulate the heat very closely, or your aluminum will melt. Using MAPP gass, it's easy to heat aluminum to the point of melting. Once the brazing rods melt, the motlen metal flows like water, so it's hard to get it stay on anything but a level surface. The rods are a lot harder and brittler (if that's a word) than aluminum, so the aluminum could pull away from the repair in high flex situations, like a boat.

 

[Silvertip]

Re: Aluminum Repair

Aluminum melts at 1300 degrees. I've used this rod to fill a threaded hole then re-drilled and tapped and it worked fine. I've also done some other minor repairs but never a boat. From my limited experience with it I would give it a shot. But as was suggested, watch the heat.

 

[luv2fish62]

Re: Aluminum Repair

I've tried those, yes very thin, i.e beer cans, they work, but for anything thicker than .010 I could not get the material to stick. JB Weld works great as long as the surface is prepped well. I choose it over any low-heat Al. rod.

RIDEPATE Thanks for your input. I have used JB weld for other projects and have been happy with the results but am unsure how large of a hole it would work with. I have 1 hole that is about 3/8" to 1/2" in diameter. I would need to back the hole with some wood and use packing tape as a release agent between the wood and JB.

My other thought was to make an aluminum patch and put some 5200 and closed end pop rivets to it.

Any thoughts would be appreciated.

 

[luv2fish62]

Re: Aluminum Repair

... They melt at almost the same temp as aluminum, so you have to regulate the heat very closely, or your aluminum will melt. Using MAPP gass, it's easy to heat aluminum to the point of melting.

fishrdan you raise a good point about the temp issue. Aluminum melts at just under 1300 and the HTS-2000 is just over 700 degrees. 500 degrees in the hands of somebody that has not done work like this is probably not much of a margin to mess with.

 

[ezmobee]

Re: Aluminum Repair

I filled a number of holes on my top sides with JB Weld and used little squares of aluminum flashing as a "backer". Seems to have worked well.

 

[dingbat]

Re: Aluminum Repair

It has been around for many years yet still gets attention as something "NEW!!"

This is the new and improved stuff. I used the previous versions and was not impressed. The updated rods are much, much better.

 

[luv2fish62]

Re: Aluminum Repair

I filled a number of holes on my top sides with JB Weld and used little squares of aluminum flashing as a "backer". Seems to have worked well.

ez now that you mention it I have some speed tape...it is an aircraft aluminum tape that is used to make quick battle damage repairs on the skin so the jet can fly another mission. The stuff is rather sticky as you can imangine to withstand high speed flight. I bet that will make a perfect backer for JB.

 

[dingbat]

Re: Aluminum Repair

The rods are a lot harder and brittler (if that's a word) than aluminum, so the aluminum could pull away from the repair in high flex situations, like a boat.

The elongation of the rods is 3% greater than aluminum. How can something with a higher elongation be harder and brittler?

 

[jasoutside]

Re: Aluminum Repair

If you are repairing small holes, find something other than the aluminum brazing rods. I have used then too, and they worked OK for what I did, but... They melt at almost the same temp as aluminum, so you have to regulate the heat very closely, or your aluminum will melt. Using MAPP gass, it's easy to heat aluminum to the point of melting. Once the brazing rods melt, the motlen metal flows like water, so it's hard to get it stay on anything but a level surface. The rods are a lot harder and brittler (if that's a word) than aluminum, so the aluminum could pull away from the repair in high flex situations, like a boat.

I gave the rods a try and had this exact same experience ^^^. I can't personally recommend them, their kinda frustrating really.

For holes n' such there are many alternatives. All sorts of combinations using JB Weld, 3M 5200, Marine Tex, rivets, alum patches can bring good results.

Have fun

 

[ezmobee]

Re: Aluminum Repair

ez now that you mention it I have some speed tape...it is an aircraft aluminum tape that is used to make quick battle damage repairs on the skin so the jet can fly another mission. The stuff is rather sticky as you can imangine to withstand high speed flight. I bet that will make a perfect backer for JB.

That should work great. You're basically trying to provide a "chewing gum on the underside of a school desk" kinda effect which keeps the plug from popping when you sand it smooth.

 

[fishrdan]

Re: Aluminum Repair

fishrdan you raise a good point about the temp issue. Aluminum melts at just under 1300 and the HTS-2000 is just over 700 degrees. 500 degrees in the hands of somebody that has not done work like this is probably not much of a margin to mess with.

Hmm, I though the temp difference was closer, like 1100* for the rods, guess I was off on that. I had bar stock aluminum start to melt as I was using the rods, the aluminum was dissapating the heat so quickly that I had to keep the flame on it to get the rod to flow. (It wasn't molten, but when I brushed it with a SS brush, the brush left gouges in the aluminum, at the verge of melting) It was a fine balancing act getting enough heat into the part to melt the rod, before the heat dissipated, and the aluminum wasn't melting. I was brazing a galvanized nut onto the aluminum, so that made things a bit tougher...

The elongation of the rods is 3% greater than aluminum. How can something with a higher elongation be harder and brittler?

Try drilling or grinding the brazed material, it's a lot harder than the parent aluminum it's sticking together. This isn't a biggie, unless you are trying to grind it down smooth, or drilling on the edge of the braze. As for being brittle, the rod material does not make a strong connection than the parent material, so the braze can pull off the parent material. I guess it's the brazed connection that's brittle, instead of the rod itself. While the rod material might have 3% greater elongation, does the (thick) brazed repair have 3% greater elongation? I guess it depends on how the repair is made as a thin braze might not pull off as easily as a thick braze, though a thin braze could fatigue and fracture faster than a thick braze...

 

[fishrdan]

Re: Aluminum Repair

ez now that you mention it I have some speed tape...it is an aircraft aluminum tape that is used to make quick battle damage repairs on the skin so the jet can fly another mission. The stuff is rather sticky as you can imangine to withstand high speed flight. I bet that will make a perfect backer for JB.

You want the backer glued to the boat so there is more surface area for the JB weld to bond to. Using an aluminum backer (like EZ's flashing) gives the repair greater surface area and less of a chance to separate.