Mig for English Wheel Frame

[sixtwoeight]

Iam used to welding thin metal, car stuff mainly, so am fully aware of the distortion that too much heat can cause, but want to know how if affects thicker metal...
I am planning on building an english wheel and have some 150x100 by about 6/7mm thick. I obviously want to keep the frame straight and true. I will prepare the joints to a "v" to help penetration, my mig is 200a.
Should i do a series of short runs?
How can i minimse distortion?
What is good practice when welding a frame? (any frame that needs to stay straight)

Or can i just turn the welder up and crack on?

Thanks for any help.

 

[WorkshopChris]

Will be interested to see what everyone else thinks, but personally at 200a you're probably on the limit for a 6+mm stressed joint. Do you have any access to a MMA set?

 

[winchman]

Might be worth buying an old Oxford set, make your frame then just sell it on, possibly for what you paid.

 

[addjunkie]

You need to consider in the set up how it will distort, and work with it, therefore allowing it to move in the right direction.

Might not be kosher like many things the alchemist welders wouldnt do, but id do it in short run with the mig. Working from one side, then the other. You could also brace the joints then weld up the joints, then remove the bracing.

Any wonkiness can be then minimized when fixing the roller mounts etc.

 

[optima21]

if you havn't seen this video before, it explains distortion, but it shows tig rather than mig

 

[gordon stephenson]

Lots of tacks before final welding.

 

[Kent]

Tack in the right order, less gaps and fast travel speed. Welds pull in on direction of travel btw

Do not go multi run just get the job in one

You might be alright with that set but weld it flat crank it up.

 

[WorkshopChris]

What diameter wire are you running? with 0.6mm at 200a you might get into spray transfer.

 

[sixtwoeight]

Ok, so my knowledge is lacking here a bit....but thanks for the replies so far.

0.8mm wire (whats spray transfer, sounds like what a tom cat does??)

As Kent says "Tack in the right order, less gaps" what is the right order?

I will watch the video, thanks optima21.

Bracing it all with temporary braces sounds good, and i can alternate sides etc..

I dont have access to MMA, was hoping 200a would be just enough.

Thankyou

 

[Kent]

You won't need to spray ( it's basically lengthening the arc so the wire feeds into the pool as a spray in the arc itself) it will actually be counter productive as it's got greater heat input
The correct order is opposites what your doing is locking it in ( even tacks pull in material) clamping helps
Tempary braces are not usually used in fact they are very rare in general fabrication ( more a car thing)
200 amp is ample. Do a test sample

 

[sixtwoeight]

You won't need to spray ( it's basically lengthening the arc so the wire feeds into the pool as a spray in the arc itself) it will actually be counter productive as it's got greater heat input
The correct order is opposites what your doing is locking it in ( even tacks pull in material) clamping helps
Tempary braces are not usually used in fact they are very rare in general fabrication ( more a car thing)
200 amp is ample. Do a test sample

Thankyou, explanations spot on for me.
Cheers

 

[Jim Davey]

Right order is the one that gives the most even weld shrinkage and 'pull'. Obviously try to space your tacks so they are equal and opposite, almost like tightening down a cylinder head. Without a detailed drawing of the fabrication in question it is impossible to guide you but you hopefully get the gist and won't completely weld up one side of it before starting on the other etc?

 

[sixtwoeight]

Right order is the one that gives the most even weld shrinkage and 'pull'. Obviously try to space your tacks so they are equal and opposite, almost like tightening down a cylinder head. Without a detailed drawing of the fabrication in question it is impossible to guide you but you hopefully get the gist and won't completely weld up one side of it before starting on the other etc?

A good analogy with the cylinder head, thanks for that. I havnt finalised the design im going to use yet but there are some very good examples on the net.

 

[outofthefire]

Mines made out of 100x50x5 I tacked it all up, welded the sides, ground them flat then stitched gussets over the top, then welded across the box where you tend to get the worst distortion welding box.

 

[Burdekin]

I used my old Clarke to weld mine no bother. You will get distortion so you need to manage it and keep it under control. Another tip is to have a plumb bob off the front and watch it and keep it spot on.

 

[sixtwoeight]

Mines made out of 100x50x5 I tacked it all up, welded the sides, ground them flat then stitched gussets over the top, then welded across the box where you tend to get the worst distortion welding box.

View attachment 86680

Looking good, how does it perform? would you do anything different?

I used my old Clarke to weld mine no bother. You will get distortion so you need to manage it and keep it under control. Another tip is to have a plumb bob off the front and watch it and keep it spot on.

Good tip with the plumb bob, think il do that as it will obviously make it a lot easier to see whats happening.

 

[outofthefire]

Looking good, how does it perform? would you do anything different?

It works brilliant, for what it is, the only thing I'd change if I could afford it would be the wheel and anvils because the wheel really is a bit rough and I've only one anvil and that's off a tractor 3 point linkage. I don't use it a lot though so it's not worth it at the moment. This it's the most recent thing I've used it for

 

[sixtwoeight]

Good work, glad the wheel does what you want.