Expanding MIG Roller Bore

[eSCHEn]

I see you can get cobalt bits, are they any use at this size? I've used smaller ones before for putting holes in PCBs and all I remember is that they were insanely brittle.

 

[CRB]

PCBs are just resin, cloth/paper and copper, hardly the worlds' most difficult material to drill.

It is more about speed and feed.

Shame a lathe is not available, but any pillar drill will do, slow and steady.

 

[daleyd]

Cobalt bits are good, though for what you are doing any decent sharp bit should do.

 

[mike 109444]

Just looked at your euro torch mod and the feed unit on your machine looks that same as the one on my very old clarke 120 machine from round 1980 ish.
Came with euro factory fitted. It's now my backup machine but I did not get any issues with feed as you seam to be getting. Have you checked for any play in the pivot pin on the top roller ? For a home use machine I would think it unlikely that the roller has worn. Does the top roller (roller bearing) spin freely? Is the bottom roller (inc groove) clean rust free and free of oil ?

 

[eSCHEn]

PCBs are just resin, cloth/paper and copper, hardly the worlds' most difficult material to drill.

It is more about speed and feed.

Shame a lathe is not available, but any pillar drill will do, slow and steady.

It was FR4 boards so fibreglass substrate which blunted normal jobbers quite quickly. The cobalt ones were awful drilling by hand even in a press as they were quite wee (0.8mm on average).

Yeah a lathe would be bloody marvelous but I'm in the ****-end of beyond so have to make do with what I've got

Cobalt bits are good, though for what you are doing any decent sharp bit should do.

Grand. Shall just get a few of the bog standard ones. You know, one for the job and err four for "dropsies"

 

[daleyd]

It was FR4 boards so fibreglass substrate which blunted normal jobbers quite quickly. The cobalt ones were awful drilling by hand even in a press as they were quite wee (0.8mm on average).

Yeah a lathe would be bloody marvelous but I'm in the ****-end of beyond so have to make do with what I've got


Grand. Shall just get a few of the bog standard ones. You know, one for the job and err four for "dropsies"

If you break 4 10 mm drill bits you should never be let near a pillar drill ever again!!

As CRB said above, take it steady and a drop of cutting fluid if you have it, or any old oil if not will also help.

 

[CRB]

I did wonder if it was hardened whether or not running a suitably-sized grinding bit through the bore would work.

Probably neither accurate enough on the diameter nor the concentricity though.

Regarding your recent post, I did too many years for Via Systems, ICS or whatever else they where called. Drilling the boards with the 0.8mm drills in one hit , but relatively few breakages. GRP does not help though.

I am not far, but the dropsies would be needed anyway.

 

[eSCHEn]

Just looked at your euro torch mod and the feed unit on your machine looks that same as the one on my very old clarke 120 machine from round 1980 ish.
Came with euro factory fitted. It's now my backup machine but I did not get any issues with feed as you seam to be getting. Have you checked for any play in the pivot pin on the top roller ? For a home use machine I would think it unlikely that the roller has worn. Does the top roller (roller bearing) spin freely? Is the bottom roller (inc groove) clean rust free and free of oil ?

Funnily enough when I spoke to Steve at Weldequip he mentioned he used to sell them many moons ago. I think this one is probably 1990 or so.
Top roller spins freely and doesn't appear beveled from wear. Bottom roller is clean and oil free but does have a light build up of rust on it, I figured it was just past its usefulness and needed replacing. There's no knurling in the grooves like the replacement one has. Embarassingly I can't tell what size the original roller's grooves are either - there's no markings for 0.6/0.8

 

[eSCHEn]

If you break 4 10 mm drill bits you should never be let near a pillar drill ever again!!

As CRB said above, take it steady and a drop of cutting fluid if you have it, or any old oil if not will also help.

I've never commited to the arc of shame on a pillar drill but I get really impatient with the crap kit I have! Think I might have a wee bit of rocol cutting fluid somewhere from my HVAC days but if not then some light oil it will be

I did wonder if it was hardened whether or not running a suitably-sized grinding bit through the bore would work.

Probably neither accurate enough on the diameter nor the concentricity though.

Regarding your recent post, I did too many years for Via Systems, ICS or whatever else they where called. Drilling the boards with the 0.8mm drills in one hit , but relatively few breakages. GRP does not help though.

I am not far, but the dropsies would be needed anyway.

Hmm never heard of a grinding bit before, I'll have to research that one. Edit: just googled them and I've seen them before but didn't know that's what they were called. Every day's a schoolday eh?

Yeah were those the ones with the place in South Shields? Had a few mates work for them back in the 90s. Never worked there myself; probably just as well with all that gold about - I'd be doing pirate impressions

 

[mike 109444]

When the wire is sat in the (correct?) groove, it should stand proud so that the top roller has something to press onto. If you look at the new roller (which is marked?) the difference between 0.6 and 0.8 is quite noticeable, there for if you have a 1.0 roller groove (on original) then it should be noticeable compared to new roller. I assume that your original roller has two groves ? and that you can see that one is bigger than the other ?

 

[mike 109444]

Another possibility might be as per post 7 on this link http://www.mig-welding.co.uk/forum/threads/sip-p170p-wirefeed-birdnest-issue.49398/
Yet more maybe take out the brushes on the motor and using a blast of air blow into the brush housing. You will be surprised how much carbon dust will come out. Then give the brushes a wipe with a clean tissue and make sure they slide easy when they go back in.The machines I work on have slightly smaller gearboxed motors (24v) 17 per machine. We do sometimes clean out the dust but if at all sus we replace. Note that even though the roller may run at say 20 to 50 rpms the motor may well run at 2000 to 3000 rpm hence the brush ware.

 

[eSCHEn]

New roller is marked which is super helpful having something to compare to.

I've done a wee impression using bluetack and the old roller has two 0.8mm grooves.

 

[mechman]

I needed a new feed roller for my SIP but as SIP themselves seem to have no stock and are as much use as a toffee teapot I thought I'd try someone more reliable.

I spotted a roller for a Clarke machine on @weldequip's site and the dimensions matched so I ordered one. Just tried to fit it on tonight and the bore on the hole in the new one is too small so I need to widen it. I've put the vernier on it and currently it's 9mm but needs to be 10mm. My question is how should I approach it?

I've no access to a lathe or any machinery more complicated than a cordless drill. I do have an extremely cheap and crap SIP pillar drill (a whole 280W of muscle, wow!) My normal way to do this would be to just send a 10mm HSS bit through it but I'd thought of using a hand reamer but that's not a tool I'm familiar with. Is a reamer suitable for this or am I trying to take too much off in one go?

When I was an apprentice about 100 years ago we were told to leave 1/64"inch about 15 thou for reaming.

 

[eSCHEn]

Another possibility might be as per post 7 on this link http://www.mig-welding.co.uk/forum/threads/sip-p170p-wirefeed-birdnest-issue.49398/
Yet more maybe take out the brushes on the motor and using a blast of air blow into the brush housing. You will be surprised how much carbon dust will come out. Then give the brushes a wipe with a clean tissue and make sure they slide easy when they go back in.The machines I work on have slightly smaller gearboxed motors (24v) 17 per machine. We do sometimes clean out the dust but if at all sus we replace. Note that even though the roller may run at say 20 to 50 rpms the motor may well run at 2000 to 3000 rpm hence the brush ware.

Hmm hadn't considered that the gearbox and motor could need a service. It turns with plenty torque but sort of "grinds" the wire in the groove rather than moving it along, if you see what I mean?

 

[mike 109444]

New roller is marked which is super helpful having something to compare to.

I've done a wee impression using bluetack and the old roller has two 0.8mm grooves.

Really? That does surprise me if correct. If you look across the top of the roller (along the groove) while upto a light source (window even) then it should be noticeable the difference between 0.6 and 0.8. If you set the pressure roller down with light pressure onto the orignal roller then try a feeler gauge between the two rollers (say 5 thou) at the front and back to see if the two rollers are parallel with each other. If ok then remove the pressure roller inc it's bracket, run the feed roller on a high speed with some wet and dry to clean it up shiny. Then running it at a slow speed look for run out, where the roller appears to be going up and down. If the motor/gearbox bush/bearing is worn this will show it, even a small amount will show by eye.

 

[mike 109444]

Hmm hadn't considered that the gearbox and motor could need a service. It turns with plenty torque but sort of "grinds" the wire in the groove rather than moving it along, if you see what I mean?

What size wire are you using ?

 

[skotl]

No not done it as it's not that kind of unit. It's much sturdier in construction; like a pre-cost saving unit. Here's a picture of it before I converted to a euro torch:
View attachment 57295

Oh wow - that is a lot more sturdy looking. Any idea what vintage your unit is?

Edit: Just spotted your later post re it being ~1990

 

[mike 109444]

Hmm hadn't considered that the gearbox and motor could need a service. It turns with plenty torque but sort of "grinds" the wire in the groove rather than moving it along, if you see what I mean?

This is a pic of the motor in my Clerke 120 much the same! but don't have a pic of the roller asy will take one next chance I get.
Does your welder have a capacitor(s) bank?

 

[eSCHEn]

What size wire are you using ?

0.8mm, just a small hobby reel.

Really? That does surprise me if correct. If you look across the top of the roller (along the groove) while upto a light source (window even) then it should be noticeable the difference between 0.6 and 0.8. If you set the pressure roller down with light pressure onto the orignal roller then try a feeler gauge between the two rollers (say 5 thou) at the front and back to see if the two rollers are parallel with each other. If ok then remove the pressure roller inc it's bracket, run the feed roller on a high speed with some wet and dry to clean it up shiny. Then running it at a slow speed look for run out, where the roller appears to be going up and down. If the motor/gearbox bush/bearing is worn this will show it, even a small amount will show by eye.

TBH I don't have the best light source beside me right now so I could be wrong on that (hear hooves think horses not zebras). I'll check again tomorrow when I've got better light to work by.

Thank you for the things to try Mike, I'll get the side off the machine tomorrow and try them - I'd really like to get to the bottom of this!

 

[eSCHEn]

Oh wow - that is a lot more sturdy looking. Any idea what vintage your unit is?

Edit: Just spotted your later post re it being ~1990

Yeah I think it's about 1990. I shall have a gander inside it tomorrow when I try Mike's fixes and I'll report back.