Bought the Tetrix a couple of weeks ago. It’s a great machine.How’d you get on with it @Ped
Hi All,
I'm looking for some advice on buying a DC tig welder for very thin walled tubing. I've got the opportunity to build a few high end steel bicycle frames but the 200amp SiP ac/dc machine I have isn't up to the job.
The SiP is OK on the general fab stuff I have been making (furniture, garden stuff etc) but it has a few problems when it comes to low amps. The footpedal gives the full 200amps (it bypasses the fascia control entirely) and on pulse setting the display just randomly jumps about so it's not clear what it's actually doing. It has other issues but they are the main ones for thin wall. I have managed to weld thin wall titanium with it though.
The tubes I'll be using will typically be .7mm down to .4mm thick. Only steel, no aluminium. The welds will not be painted.
My budget is £2500. I prefer to use a foot pedal and if possible I'd like to keep the CK torch I have.
It's my money btw! So if I can get exactly what I need for less I'm all ears!
Hi Ped,
have you allready welded some bicycle tubes? I would be interested in the results ;-)
zeppelin builder is right, proper tube prep and nearly no gap is what you should allways go for.
Brazing would be another option, but more work and you can see the integrity of a weld, but it´s hard to see the quality of a finished fillet brazed joint after the finish. Anyway I guess, its not your decision, your customer decides.
I offer my frames also fillet brazed, but more then 95% choose the tig option, because I just have to ask a few hundred € extra for the finishing of the fillets..
Beautiful!! and the miters are perfect for welding. That should help a lot.
Did you grind them on a beltsander?
I use holesaws as well in a mill. That works fine for me.
Grinding is interesting but produces a lot of dirt in the workshop and a little attachment to fix the seatstays or chainstays as a pair on the machine is easier to mount on a mill I think.
The saws are cheap and you can cut dozens of tubes with one.
Thats why I still use it.
Hi,
when cutting really thin and hard material like (Deda EOM 44mm 0,4wall for example) a tight fitting plastik (pom) plug hammered into the tube helps to stabilize it during the cut. That protects the hole saw also a little from loosing teeth.
It´s one more step but might be worth to prepare a plastic plug before the tube cut on the lathe.