Bill

Plenty of joint area there which helps.

I've done satisfactory repairs to cast iron with ordinary stick welder rods using the old fashioned, field expedient, puddling approach. The basic process is to create a nice wide Vee in the joint area for easy access and lay down multiple, thin layers of weld metal using a thin rod at the lowest practical current. During cool down the weld area should be aggressively peened with the chipping hammer. Once you have a reasonable build of weld metal you can finish off with a more usual, but still small, size rod and current. Still can't do it in one hit, two or three layers on a joint like yours I'd say, and aggressive peening during cooldown remains essential.

My practice is to do the small rod build up bit first then leave for an hour or so to ensure its all properly cooled down.

Theory is that the initial multiple thin layers pretty much isolate the joint proper from any carbon migration and associated brittleness. Aggressive peening stretches the weld surface minimising stresses due to contraction.

All goes much better with a good inverter welder than with a buzz box because you can reliably operate at lower currents. I'd have just Vee'd out the original crack and stuck it together. But I've done it before a time or three and my little Fronius welder is really good.

If you have a choice use the most ductile breed of ordinary rod you can find. Never, ten thousand times never, use "proper" cast iron welding rods. These must be used on preheated castings and the instructions followed exactly. I recall a friend being given a couple of such rods which he used with disastrous results. Stuck together OK but massive lumps everywhere and harder than a woodpeckers beak. An angle grinder would barely touch the stuff. Knowing him he'd got hold of something really exotic for super-strength repairs.

Clive

The only time I was involved with cast iron welding (steam loco cylinder) the advice was to use nickel rods, pre heat the casting and then after welding cover it up to let it cool slowly. As it turned out the box of rods was so expensive we could probably have sent it to a specialist. However it held for 30+ years until the cylinder was replaced for other reasons

Stupid question, what is a D-W?

Adrian

I had an old-style Myford countershaft unit that had completely cracked across one arm. I took into college and the welding instructor SIF bronzed it – producing a very strong (but not exactly pretty) repair. As I think I've related before – he did swear a great deal during this process (which was something he did a good deal of anyway) but I gathered it didn't go that smoothly at first and that possibly I wasn't his favourite student either…

From what I recall – it was a two part process – he first heated the part up to red-heat, let it cool somewhat and then reheated and brazed it – all using Oxy/A of course. A highly skilled man.

Regards,

IanT

Edited By IanT on 25/05/2020 13:33:14

Your Dore may have had the clamp made too slack for the tube, hence the over tightening.

The thing with cast iron rods is there are several types, all have a percentage of nickel between 90% and 99.5%. The lower % makes them cheaper but the resultant weld goes very hard. Weather preheating would stop that I cant say.

I've found cast iron welding easier (less sticky) than normal rod welding and once you get a good layer of nickel rod on both sides you can get away with a switch to steel rods.

Use 99% plus.

Personally I would carefully consider remaking the clamp in the correct size from steel tube and weld new ears on it.

As a rank amateur stick weilder I have used both the Lidl transformer and the inverter welders

The inverter welder gives off almost no smoke compared to the transformer one and is far more reliable

The transformer one tripped quite a lot, the inverter hasn't missed a beat

They were like night and day for me

Sparking up seems to depend a lot on the rods, I always do a pre-heat sparkup because most of my runs only last a few seconds and I need a first time start

I don't know the answers, but are Dore-Westbury castings still available, and how much would just the broken one cost – It is not that big??

A final thought for you. I have been looking at pictures of D-W and the MkII seems to have a thicker angular casting. It looks that it could be machined out of a solid block of CI. Could be an answer if all else fails.

This site has a picture of it **LINK**

Adrian

I welded this vice, if you look where it says England, going diagonally up to the machined surface, the whole front of the vice snapped off (not me, I pulled it out the skip at work) it was a nightmare, I wouldn't do it again for love nor money.

I think brazing is the way to go.

Edited By Pete. on 26/05/2020 20:38:14

The casting cracked because of an excessive tensile load at that point.

Will an adhesive have a greater tensile strength?

If you have a lathe with a large enough capacity, you could possibly make a replacement from a block of steel.

A flycutter will mill the faces that need to be flat. A boring bar will produce the bore. A slitting saw on an arbor, between centres, with the job held on the Cross Slide or Toolpost, will produce the split. A similar set up of the job will allow the drillings to be made.

Not necessarily an easy or quick job, but not impossible.

And being steel, less likely to crack in the future.

Howard

Would have been relatively easy when there was a foundry on nearly every street. High Nickel is the weapon of choice BUT, in this case, replace rather than repair. In clamping situations, there is no substitute for parent metal.

Regards Ian.