Welding cast iron vice

Hi, I’m restoring an old Wilson Turret vice, and would like advice on the best/easiest way to fill a few drill holes in the cast iron vice base. Would it be possible to mig or TIG filler into the holes, or would brazing using one of the modern multi use filler rods be the way to go?

THANKS..

Cosmetic filling? JB weld.

Structural filling? No idea, but maybe JB Weld again

Part of the damage is on a corner, so yes it is structural as in that JB weld wouldn’t hold up to knocks etc..

cheers

With a hole I would MIG it but I don't know anything about TIG

Stick would make too much slag and is less accurate for those weeny jobs

80+ amps? just enough to fill, don't stop until you're finished and leave a dome to grind off

edit: if its structural 100-130 better

Edited By Ady1 on 21/01/2022 19:07:47

I once welded some broken cast iron control handles on a horizontal mill using a stick welder. You need special filler rods, and the casting needs to be heated up - not red hot, but a good long soaking in a bed of glowing charcoal.

It was actually easier than normal stick welding - the arc seems more stable and there's less slag. The arc was a rather pretty blue colour too.

Proper cast iron MMA rods are of high Nickle content (90%) and very expensive ! some pre heat is a bonus and one needs to try and burn out any oil. Clean and V out to give a good weld if in 2 bits and allow to cool slowly after welding. If clean you could try MIG, or if you have Oxy- fuel brazing ! Welding cast iron very much depends on the iron quality as to success along with how it's done. Good Luck. Noel

I've repaired cast iron with both stick and MIG with only home shop facilities so no pre-heating.

MIG, in my hands at least, tends to come out brittle with a tendency to crack on cooling. On on older "economy" cast irons MIG doesn't deal well with the high free carbon content.

As Ady1 says using stick in the normal manner tends to give you slag problems and cooling contraction may crack things.

Avoid the specialist cast iron repair rods unless you have preheat facilities and the skill to use them as per book. Wonderful if used properly but in the Home Shop you are highly likely to end up with glass hard pigeon droppings and an unsalvageable job.

How do I know. The unsalvageable job came to me after an "I know what I'm doing expert" messed up.

Best way I've found is to use small stick rods with a puddling technique. Which, back in the day, was the approved method for field repairs.

Choose a nice ductile rod if you can.

The DIY specific market rods from reliable suppliers tend to be good at this. But avoid the "cheap for DIY market" from "who the heck are they" folk. Some of the no-name, white box imports can be really odd and the alleged type numbers clearly not what is in the box. That said some white box no name are superb. Inherited two boxes from a friend that were wonderful. No idea what they were because the number corresponded to something rare, expensive and a right pain to use.

Puddling technique is basically to clean up as well as you can first then apply a thin layer of stick weld using a small rod and the lowest current that will give good fusion. Tap with the chipping hammer as it cools. The peening largely counteracts any stresses due to cooling contraction. The thin layer and relatively low temperatures minimises carbon migration into the weld metal. Allow to cool properly and repeat. After 5 or so layers you can switch to a larger rod for faster build but still don't try it in one. Peen when cooling as before. As you are now welding rod material to rod material carbon migration isn't an issue. Using a ductile rod helps reduce cooling stress too.

A good inverter welder makes life easier than an old fashioned buzz box. Victorian architectural brackets et al have lots of free carbon. Welcome to the coal miner chic look! Jobs to avoid.

Slightly OT here is a pro repairing a cast iron vice without pre-heat.

**LINK**

https://www.youtube.com/watch?v=KX7ajWCxpcM

He broke it so he fixed it.

Clive

PS There is a build of one of his big "weld up from plate" vice design in my future. Just have to source the tubes.

Edited By Clive Foster on 21/01/2022 20:14:33

Edited By Clive Foster on 21/01/2022 20:15:38

MIG? You would need cast iron wire for that.

Arc or TIG perhaps. Seen a similar job done on an Abwood vice.

Warm the rods , and work if possible, before and apply in several layers to minimise heat build up and risk of cracking as the work cools.

Last op will have to be to file / grind back to the original shape. If a hole is involved, a rat tail file is going to be necessary

Howard

Has anyone any experience using 55%silver solder for brazing cast iron?…Youtyhas a few videos using this..

If you have the broken piece, brazing may be the better bet, since temperatures will be lower

Hopefully the broken surfaces will be clean to make life a little easier.

Howard

Hi, something like these stick Weldability- Ni-Ci electrodes should be OK for cast iron. With some cast iron electrodes, you may only need little or even no preheat, but it does depend on the job you are doing and short runs and peening before each run cools will help distortion and cracking problems and over heating can cause more problems that it will solve. Always best to follow the manufacturers procedures for successful results.

These Eutec Trode 2-44 might be a better bet, but they are likely to be pricey, but if you know anyone who uses them, they might sell you few.

Regards Nick.

Edited By Nicholas Farr on 21/01/2022 21:16:23

The actual composition of the iron in question makes a huge difference to how well and how easily it welds.

Had to repair a broken eye on the banjo bracket of a 1960's SouthBend lathe. Allegedly made from what the Americans called "semi-steel" ie cast iron with a fair bit of steel scrap in the mix. Welded like a dream. Heck I've had more trouble with plain ordinary mild steel.

Good links from Nick but my, admittedly limited experience, is that the specialist electrodes are biased towards the professional needing to do a relatively fast job so the customer can afford it. Flip side is you need the experience, skills and equipment to do it right. As always with welding getting the speed of motion and volume of the weld puddle right is very important for best results. The more specialist the rod the more important this becomes.

Puddling with an ordinary rod takes ages but its very tolerant of less than ideal technique.

Which is why I use it.

I just don't do enough welding of cast iron, or any other weldg for that matter, to get professional standard good.

Clive

I have a few drill holes to fill, and a separate cast iron item that is cracked..I was hoping to grind open the crack and fill..

John

Puddling works a treat on a nicely ground open crack.

But I would say that wouldn't I.

I start with 1.6 mm rod at about 30 amps on my Fronius inveter welder. Move up to 2.4 mm or 3 mm when its time to close the gap.

For drill holes I find Devcon metal loaded filler much easier to use and get a nice flat surface on than weld. JB weld always seem soft to me and tends to flow during setting which makes for a harder job. Especially if you can't lay the surface to be repaired flat.

Devcon isn't cheap and smallest tub is relatively large for home shop types so I don't always have any to hand and have to weld.

If the drill hole is just a dimple then 1.6 all the way.

Deep ones I tap, screw a stud in then weld over the top.

Clive

Nearly forgot because it's been a few weeks since I last welded

If you go stick for any part of the job go over 100 amps or there's not enough heat for the slag to get out and you can get some really junk welds(2.5mm sticks)

MIG can go lower because the slag is like a fine dust powder but as mentioned the weld can be extremely hard compared to the surrounding metal

And the better your welding machine is the easier it is to do a nice job

Edited By Ady1 on 21/01/2022 23:03:22

My preference is oxy/acy with cast iron rod and borax flux. Good color match and the welds are machinable. Proper preheat and slow cooling are essential for machinable welds.

Hi John I have had to repair holes in cast iron over the years and if the hole is in a suitable area ie not on an edge or corner of casting I just clean up the hole, turn a cast iron plug to suit the hole, a tap in fit, and make sure it protrudes slightly when tapped in. Tap in the plug and slightly peen the top with a punch or ball pained hammer, and then file and emery the top flush. You can't see the repair and there is no need to weld etc with hard spot or cracking possible problems. It is also possible to do this on a corner or edge as long as you can tip the casting to suitable angle and drill the hole for plug. I have also done holes which over lapped with similar method but the holes need to be done on a mill and slot drill as the drill would push over and make repair difficult as you mill the second hole averlaping the first plug.

David

Edited By David George 1 on 27/01/2022 08:01:03

Hi John again. I have a few bronze Sifbronze brazing rods you can have if you want. If you are near to me you could collect or I could post them. This is a repair to a Stuart casting I did recently.

David

Thanks everyone for your ideas..

David, yes I’ve used the plugging method before with excellent success, but this is a cluster of holes that extend to the corner of the casting.

is it Sifbronze number one that you used?…does the finished repair match the cast iron colour, giving an invisible repair, which I’d like, or is it more of a brass colour?

cheers John

SIF BRONZE as the name implies is a bronzy colour, so the repair will be obvious. It depends on wether you want a serviceable item or an ornament ? The nearest match will be something like Murex CINEX in 2.5mm but their costly ! Noel.