Hi all, need to weld a 15mm axle plate to 3mm cds tubing my welder is not up to the job being 190amp so hoping to pre heat the axle plate with my
propane torch then weld?
Any thought/ideas will be great, haven't got the power supply to hire a 250amp welder
cheers
That's a huge difference in thickness. A bigger current would probably see the 3mm just melt away.
Can you grind out a deep root into the plate ? Take it down to 3-5mm and 10mm wide then build up
several runs of weld, thus getting the preheat required at the same time.
I often preheat thicker components with a propane, since my welder is a mere 140A Migatronic (5000MX). Like the other guy says though, 15mm is one
helluva thick component. I'd try the grinding and building up method.
I *guess* this where TIG would be great???, you'd possibly heat the 15mm plate to hell and tickle the 3mm.
Take the contraption to a Decent Shop and have them weld it up for you.
Small mig welding machines of up to about 200 amps welding output; normally run using short circuit transfer, but semi-dip transfer is easily possible with 0.8mm mig wire and spray transfer can be achieved using 0.6mm wire, but this is difficult to control. Turning up you welder to full and reducing wire feed slightly will give a spray transfer. It sounds like a hiss rather than drops going onto the metal. This is very good for burning into thick steel. Keeping the heat mainly on the thick side and moving over to the pipe swiftly. Difficult to explain but hope this helps. The only time I have ever preheated is on cast.
low carbon mild steel should be heated and keep above 343*c before and between runs us a 343 temp stick.after welding tap with hammer to normalise
heat affected zone and allow to cool in air
grinding the plate will help but will allow it to bow easier
all good points the 15mm axle plate is for the rear of my chop/bobber bike build, going to have the same issue on the steering neck.
Looks like a combination of routing and preheat..
cheers
A job for a stick welder methinks.
Paul G
quote:
Originally posted by 907
A job for a stick welder methinks.
Paul G
You can pick up a cheap stick welder for very little money nowadays surely a better proposition.
Cheers,
Bob
The reason I've stayed put at 140A for the mig (apart from the cost of replacing it with anything bigger), is that I have a fan-cooled SIP AC ARC
(240AC, 1ph, 40A feed). The thing will weld anything heavy, last job was the build table, next job will be to repair the gate posts...
I wouldn't have the skill to use this attaching a vapourisable 3mm thing though to a 15mm other thing.