Morris Minor Owners Club

Trying to get my SIP MIG welder back in service. Yes - I know you all say SIP is rubbish - but SIP I have and it will just have to do! Problem is wire feed - If I cut a straight length of loose wire it feeds through fine and I can burn a great length of weld. But when i try to feed from the large drum of wire - it stutters and stalls - and the wire feed is hopeless. I don't remember having this problem when I first got the welder (many moons ago) - and was using the normal small drum of wire. Has anyone else found the large (and therefore heavy) drum to be the problem ? Also - will 0.8mm wire feed through better than the 0.6 wire I have at present ? My plan being to buy a small drum of 0.8 wire - and try that! Any other tips/suggestions how to improve the wire feed will be very welcome ! Roy

Apparently one of the big problems is that the two rollers flex apart and that can be solved by adding an additional restrainer bar over the two rollers.

Gimme a min or two and I'll cobble up a rough diagram....

And here we go....

Hope this is clear enough<br><br>

I've already increased the spring force quite considerably Dan ! The lower roller has a tiny groove - in which the wire runs, and the upper roller is just a smooth faced roller bearing. I wondered about 'roughing up' the face of the upper roller - although I think it's the lower (grooved) roller that is driven.
Aye - that's the set-up - good drawing there Dan ! However the upper roller is flexibly mounted - and held down by a thin leaf spring with a bolt for adjustment - I've added a packing piece to increase the compression - to the point where the spring leaf is almost dragging on the wire. I could change it further - but the drive motor actually seems to be struggling too - when it's not slipping!
There used to be a link to a good 'welding' forum - can anyone point me please ?
Edit - Here's the forum ! http://www.mig-welding.co.uk/forum/index.php

Been about 10 months since I last stared at the SIP wondering what in heck was wrong with it, so can't really remember how it functions I'm afraid

I've nerver been able to use the big drums sucessfully on my Clarke - I just think they are too heavy for "hobby" welders....

The plastic liner is prone to clogging up. Replace it with a steel one and it should make the wire feed much better. Here's one I found on ebay; http://cgi.ebay.co.uk/QUALITY-MIG-WELDI ... 7C294%3A50

its the bottom one that drives the wire Roy. We had the same experience with the tensioning spring, I actually had it touching the wire at one point.

This is the problem with SIPs unfortunately and was also the problem with a friends welder (a SIP copy) we put a eurotorch on it and its been fine since.

I would suggest replacing the torch liner to start with and keeping the torch as untwisted as possible, if that doesnt work a new torch or a eurotorch conversion would probably help

Thanks all - I found this 'fix' on the MIG forum - will try it tomorrow !<br><br><br><br>

Seemingly stops the unit flexing - which loads up the motor.

And this v similar solution from a lad who had exactly the same problem as me - ok with small reel - hopeless with large reel.<br><br>
It's basically your 'fix' Dan. Thanks for your help!
Hoping for great success tomorrow!

There also seems to be an issue with the wire feed drawing current from the same transformer as the welding current. Have a read of this for a solutions.

http://www.mig-welding.co.uk/sip-wirefeed.htm

I think there is also mention of repositioning the mounting hole when using the large wire reels for better delivery to the rollers.
I shall be doing these mods to my SIP as I have been dogged with wire feed problems as well.....

Yes I have read the ones about electric feed to the wire drive - but I'm struggling to believe that's really an issue. Will be trying the 'brace' first - they seem to think it solves the problem - I hope so!

Give your liner a blow our with the air gun, amazing just how much metal dust is stored in this , and blowing it through from both ends can work wondres.
Re big reels do your welders have spool brakes, ie two adjustable springs that tighten the spool which stops the weight of the reel from continuing its rotation, ie firing out wire when you have welded.

No reel brake - it's a very budget machine Jon! The trouble is getting the heavy reel to start turning - run-on is good - it gives some free wire for the restart!! Was having trouble finding my weld mask - but it seems I don't need one anyway!
http://www.youtube.com/watch?v=MrjMyEVQ6xk

I may be stating the obvious, but the spindle has a keyway. Btw these sip welders are great! Speak as you find!!

My SIP has had similar problems in the past, a couple of things have helped in my case -

Using 0.6mm wire - still a 5kg drumm.

I had terrible problems a couple of years back with another 5kg drum. It was stuttering badly all the time - impossible to weld with. My neighbour asked if I stored the wire in the welder all the time - which I did. He checked the wire and found that had started to rust giving a rougher surface - his theory being that the rust on the wire (very slight) was enough to cause wire feed problems.

I bought a new drum and now store it in the house when not being used and I have never had any bother since (fingers crossed)

Not understanding ' the spindle has a keyway' ??
Any way - carried out the Meccano modification as above - and it's 90% better! I can now weld a super straight line with only the slightest of jerking as the wire feed yanks the big drum into rotation - as soon as it's turning - the wire feed is silky smooth. I think that initial jerk will only disappear when I go back to a small reel. Unfortunately I threw the empty small reel away when I bought the large reel - so nothing for it but to buy a new reel.
I blew through the liner Jon - nothing much came out - and feeding through the new length of wire was smooth and easy - so i think the liner is ok. Many thanks all who came up with ideas and suggestions - much appreciated. Roy