Welding Tips and Tricks

I am new to welding. A friend of mine asked me to fix his industrial trike. It has a broken "band-brake" which consists of a collar which is threaded into a 1/6" disc. The threads are stripped. I would like weld the collar to the disc.

I am looking for advice on how to proceed. Both pieces attract a magnet.

Can these pieces be welded since they are of very different thickness?
What type of welder should be used?

Any input is appreciated.

Thanks!
Jason

If the 2parts will thread back together leaving little chance of mis alignment then I think the easiest would be an autogenous Tig weld on the thin edged side - putting much heat in on the flat side will likely cause it to warp.

Be aware, the collar appears to be zinc plated and that will play a bit of havoc with welding (TIG).

The trick with welding differing thicknesses is to focus the majority of heat on the thicker piece, then whip over to the thinner side.

You didn't say what type of welder you have. Practice on some similar sized scrap.

Just realized we are in the mig/flux forum.

noddybrian wrote:If the 2parts will thread back together leaving little chance of mis alignment then I think the easiest would be an autogenous Tig weld on the thin edged side - putting much heat in on the flat side will likely cause it to warp.

The pieces do fit back together so there should be no misalignment. I will take a look at autogenous Tig welding as I am not familiar with it.

I was looking at flux core welders like the Lincoln Electric 120-Volt MIG Flux-Cored Wire Feed Welder.

Thanks for your input
Jason

cj737 wrote:Be aware, the collar appears to be zinc plated and that will play a bit of havoc with welding (TIG).

The trick with welding differing thicknesses is to focus the majority of heat on the thicker piece, then whip over to the thinner side.

If there is zinc plating would this cause problems with flux core MIG welders as well?

Thanks!

Turbo wrote:You didn't say what type of welder you have. Practice on some similar sized scrap.

Practicing on similar sized scrap may be a challenge. I don't know exactly what these parts are made of. I think I can get some thin and thick steel plate to practice on.

Thanks for your input.

Many years ago I had a similar setup with a hub into a sprocket. A local machinest / handy guy silver soldered it together and it ran a small hydraulic pump for years with no problems. Just a thought.

homeboy wrote:Many years ago I had a similar setup with a hub into a sprocket. A local machinest / handy guy silver soldered it together and it ran a small hydraulic pump for years with no problems. Just a thought.

I had not considered silver solder. Because of the high shear stress the bond will be subject to, I would like to try silver brazing, if I can heat the pieces to a sufficient temperature with my propane torch.

"The shear strength of brazed joints typically exceeds that of soldered joints by a factor of five. " https://ewi.org/should-you-solder-it-or-braze-it/

I would imagine if the silver solder/brazing did not work I could still weld it.

Thanks for the input!

I don't really have any knowledge about the process but I have also had the odd tooth replaced in dry cut saw blades and the teck claimed to use silver solder and none have failed so far.

Silver solder done well will hold something like this but would put a lot of heat in & the nature of the stresses created forming the drum part means they often distort badly out of round / true - if I had to solder / braze it then I'd use oxy/acet - not propane - yes Tig hates zinc but it's only a few thou that will clean off with chemical or abrasive & still welds OK ( unlike hot dip galv )- I thought the question was what would be the best / ideal method even though it's posted in the Mig forum - really any welding process will do it with experience - if I'm reading this post right & you don't own a welder now I question if the part is worth your expense buying one - if you were going to buy a Mig anyway & this is your first job I'd say yes you can use MIg but allow a fair bit of practice time prior to the actual job - if possible buy one that will take gas / solid wire even if you do this with fluxcore & yes fluxcore is quite tolerant of plating - it will just burn off in the cloud of other s#it that comes with that wire ! obviously it would be better to remove the plating first however it's going to get repaired.

I may try to braze the parts. If brazing does not work and the parts are not ruined, I will buy a welder and try welding it, after practicing on scrap.

Thanks for all the help!

YOu can easily remove the zink coating with some muriatic acid, one of the Easy Off oven cleaners (not sure which one) should also do the trick just let it sit for a while (in a plastic back or such so it wont dry off)

If you have not already bought yourself a welder... Do your friend a favor --- take it to a pro. Even if you have bought yourself a welder... Do your friend a favor and take it to a pro. I have been teaching myself to weld for over a year and I would never use something from a friend to learn on. The way I look at it when I screw something up that is practice material. If something holds together and works like I wanted that is a finished product. Neither would be for a friend unless they weren't that good of a friend.

I would clean with detergent, then acetone, then scratch it up with 100 grit, then use a gel super glue. Harder than epoxy.

JB Weld would probably work cleaned the same way and you could use a popsicle stick to form a nice fillet.

Always prove your glue before gluing.

Zero heat distortion with gluing.

Most glue failures are due to improper prep.

Either glue can be released with enough heat.