Noob questions

[Rasher]

Hi all

First post, so here goes with 2 questions......

I have a SIP HandyMIG, it seems OK for sheet panels but I've been messing around and doing some experimenting and it doesn't seem to be able to handle thicker stuff (no penetration). Am I right in thinking this is because it's just not powerful enough and that all it can really handle is thin stuff?

Second question: If you have been welding with a thinner wire (.6) and go up to a thicker wire (.8), everything else being equal, how would that effect things?


Thanks

 

[Sparkey]

Hi Rasher, the current range for that welder is from 25 to 90 amps...so it will weld up to about 4 mm steel, right?
So i guess you've answered your question yourself already it's not powerful enough...

Ah well, if you'd like to change the wire size, you would have to change the feed roller and the contact tip too...otherwise the wirefeed will be a disaster!

But maybe someone has another opinion on this? guys?

 

[Rasher]

Thanks Sparky

If it should do 4mm then i must be doing something wrong like maybe going to fast.....I will experiment over the weekend and see if i can improve!!

The .6 thinner wire came with the welder but when i went to get another roll all they had was the thicker .8 wire so I bought that. I think the wire feeder will be ok but you're right, I'll have to get a bigger tip. I suppose, I'll find out what the impact is when I'm experimenting!

Thanks again

 

[paulmowers]

I may be corrected here, but I had always thought that using thicker wire would reduce penetration for a given amperage but by the same score is obviously able to handle higher power settings without burnback (when the wire melts right back to the tip).
I would suggest turn power up, back off wire speed because too much just gives you a high build of weld metal which also makes you travel faster which leads to less heat in a given spot and less penetration, I have also been told that too much gas flow can cause cooling of the weld area, obviously you have to have enough to prevent oxidation of the weld metal (the reason for the gas in the first place).
good luck with it.

 

[candygt]

Hi Rasher,

Unfortunatley I think you misread Sparkeys post. He is confirming your thoughts that its not really powerful enough. 2-3mm is will probably be the limit without prep on max power.

If you prep both edges in a V and weld in multiple passes it would probably be possible but im sure someone with more exerience can confirm that.

 

[Wozzaaah]

I would suggest turn power up, back off wire speed

That will put the machine into horrible globular transfer mode where the wire melts into a ball then drops into the weld pool rather than dip-transfer where it's dipped into the pool, burns back, dips etc.
The result is a crap weld with lots of spatter.
The general rule of thumb is that if you increase the voltage then you also increase the wire speed and therefore the welding current.
You also use bigger diameter wire for thicker stuff, 0.6mm is ok for thin stuff but for anything more than car body thickness 0.8mm and above is preferable.

Rasher, realistically your machine is ok for probably up to about 2-3mm with some prep but forget it on anything thicker if you want it to be strong. The blurb may say 'up to 4mm' but that's a bit optimistic and relies on all the parameters being text-book.
If it's just decorative stuff then it'll be ok though.

 

[Sparkey]

Hi Rasher,

Unfortunatley I think you misread Sparkeys post. He is confirming your thoughts that its not really powerful enough. 2-3mm is will probably be the limit without prep on max power.

If you prep both edges in a V and weld in multiple passes it would probably be possible but im sure someone with more exerience can confirm that.

LOL SHE....
No worries, i'm not offended!

 

[candygt]

LOL SHE....
No worries, i'm not offended!

*grovells for your forgiveness*

 

[Sparkey]

*grovells for your forgiveness*

no need to! I'm used to it!
How could you know if we don't see the actual people behind the nicknames!

 

[malcolm]

If it's got a 90 amp max then 2mm is your limit. 3mm with careful prep. Ignore what the manufacturer says. Had a play with a Clarke 90 a while back and wrote up the results: http://www.mig-welding.co.uk/clarke-90.htm

 

[Rasher]

Thanks for the input everyone!
I'll be testing everything tomorrow.