I had 1/4" green stuff and no easy heat source. Basic idea is the same as Projectnut's method: clamped 1/4" thick brass bar scrap in vise, cut urethane ends nice and flush bbutt joint, heated brass with torch until extra piece of urethane would melt on contact (sizzle is too hot), sandwiched end of brass between urethane ends then slid off and pressed together when melty. Hard part is judging when melty enough (friction on brass gives good indication), and sliding off together so ends join concentrically. If this method is your only option due to lack of tooling, buy some extra to practice technique. When you're happy with how the joint looks on a spare piece, give it a good tug to see how good it really is. If it holds, move on to the real deal
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Round Belting
- Thread starter ddickey
- Start date
I had 1/4" green stuff and no easy heat source. Basic idea is the same as Projectnut's method: clamped 1/4" thick brass bar scrap in vise, cut urethane ends nice and flush bbutt joint, heated brass with torch until extra piece of urethane would melt on contact (sizzle is too hot), sandwiched end of brass between urethane ends then slid off and pressed together when melty. Hard part is judging when melty enough (friction on brass gives good indication), and sliding off together so ends join concentrically. If this method is your only option due to lack of tooling, buy some extra to practice technique. When you're happy with how the joint looks on a spare piece, give it a good tug to see how good it really is. If it holds, move on to the real deal
I have round and flat urethane belting. I have flat running my tool post grinder spindle, and round running my work head on my cylindrical grinder.
Also used a flat belt on a surface grinder for a short time.
I put them together with a heat gun. heat the ends and put together. Trick is to put together and not shift position till cured.
Never used anything fancy, but a bent piece of sheet metal works for flat and a piece of angle works for round.
Two bent pieces of sheet metal one shorter than the other works well for me on flat. Put it in the longer one up against the corner and press the shorter one down on to it. Most all of the excess melt is pushed off to the one side that way. You must be careful not to lose the pressure pushing the ends together.
They are heated all the way through when joined and they retain heat well. Takes longer than you think to cool and cure.
Cooling under water works. Once cured the weld is as strong or stronger than the original material.
I trim with razor blade usually.
Projectnut ideas with wood burner and clippers are great also.
Biggest mistakes I've seen guys make are "not holding position steady" other one is "trying it before fully cooled"(pulling on joint to soon)
Also used a flat belt on a surface grinder for a short time.
I put them together with a heat gun. heat the ends and put together. Trick is to put together and not shift position till cured.
Never used anything fancy, but a bent piece of sheet metal works for flat and a piece of angle works for round.
Two bent pieces of sheet metal one shorter than the other works well for me on flat. Put it in the longer one up against the corner and press the shorter one down on to it. Most all of the excess melt is pushed off to the one side that way. You must be careful not to lose the pressure pushing the ends together.
They are heated all the way through when joined and they retain heat well. Takes longer than you think to cool and cure.
Cooling under water works. Once cured the weld is as strong or stronger than the original material.
I trim with razor blade usually.
Projectnut ideas with wood burner and clippers are great also.
Biggest mistakes I've seen guys make are "not holding position steady" other one is "trying it before fully cooled"(pulling on joint to soon)
When I needed to join ¼" round belting, I kludged up a heating tool much like those described by the previous three posters. Mine consisted of a chunk of ½" x ⅛" aluminum bar, with one end held next to a propane torch with bailing wire. Heated that end in the flame, briefly held the cut ends of the belt against the end that was well away from the flame. Then I used a homemade teflon v-block to guide and align the belt ends as I pushed them together. Used a razor blade to trim the joint. Hadn't thought of a nail clipper. Thanks, projectnut!
I use this belt quite a lot on the machines I build. I have a soldering iron with a flat plate of aluminium where the tip used to be. Stuck to this is some self adhesive teflon tape. As previously posted melt the two ends and then push them to gether . I have made a sliding clamp for this because it lines the two ends up and and then holds it in position while it cools. Not moving the join while it cools is critical in my experience. The material certainly takes a long time to cool.
That is the sort of belt used on old UniMat DB-200s. Of the two types, I prefered them over the rope twisted type. I have made a couple of splices using a soldering iron in the days before Eastman 910m (super glue). Since then, I have used Gates 5M series belts. I find they fit the sheaves quite well and are easier to cut pulleys for new work.