I was speaking to a machine rebuilding company....

[cuemaker]

I am going to be sorta vague on the who's and what's as I am uncomfortable mentioning names and business's...

But, we got a new to us machine for making a threaded product. I noticed that the carriage bounced all over the place. So I called a company that rebuilds these old machines and got to talking. A piece of info I got is that when they grind ways, to compensate for lost of material, they spray weld nickel to the bottom of the carriages to build up the surface. Then they grind/scrape back into fit. I asked about Turcite and the like and he replied that they dont like it as the have had mostly poor results with the product.

Since I know nothing, I asked about spray welding and he described it an attachment to a torch, then pour nickel powder into the flame and it deposits material on the a very hot mating part.

Is this commonly done?
Does the surface that gets the nickel buildup suddenly become "hardened" because of the nickel?

After they heat the part to about an orange color, they do the spray weld, then let it cool naturally. I thought cast iron, especially with a filler metal, tended to crack if not cooled very slowly.

[Euph0ny]

I'm no welder, but I do believe that spray welding techniques have seen satisfactory use in restoring the pivoting surfaces of worn break-open shotguns in order to return them to servicability. It sounds like a similar, if smaller-surface, application.

[1-800miner]

look up "flame spraying". Its been around for a long time.Used a lot for building up worn shafts.
I have had two obsolete crankshafts sprayed back to tolerance.

But find a guy that knows his stuff,there are some butchers out there.

Not just nickel, they can spray many types of additive metal.

[flylo]

Couple years back I bought 2 complete systems from the guy that did this for Bendix. 2 pickup. 1 trailer & 1 van load. a complete powder system & wire system. 50+ different powders, a skid of all kinds of wire, 100+ pounds of tungsten carbide, 10+ guns, lathe mounts, spares, powered wire feeders, powder hoppers & shakers & on & on & on. My mobility just won't let me do it. I've talked to a couple guys that specilize in it & they make a killing.

[flylo]

I just looked under flame spray & spray welding on Ebay & found out I'm RICH! As soon as I sell it pints are on me boys,! Yipee!

[cuemaker]

Well now.. I know where to go to get setup for this....

[j king]

The surface needs to be clean and oil free.i can't see it working with oil socked areas..

[rode2rouen]

So I called a company that rebuilds these old machines and got to talking. A piece of info I got is that when they grind ways, to compensate for lost of material, they spray weld nickel to the bottom of the carriages to build up the surface. Then they grind/scrape back into fit. I asked about Turcite and the like and he replied that they dont like it as the have had mostly poor results with the product.

It's not surprising that a Co. that has used one technique to repair machines for many years could have so-so results with trying another technique. How long has the outfit been using flame spray to rebuild machines? Do they have an established reputation? Will they offer any references? Check them out, they could be a viable solution to your issues.

I have used flame sprayed crankshafts, both cast iron and steel, in gas and diesel engine rebuilds with good results.


Rex

[loose nut]

Spray build up has been around for a long time. It can be used with a hand torch, looks like a cutting torch but has a attachment point for a cup reservoir on top, or it can be a bigger unit that can be mounted on another piece of equipment like an old lathe for spraying shafts etc. I'm sure by now there are cnc equipped spray machines around also. If done right it works very well.

[camdigger]

The surface needs to be clean and oil free.i can't see it working with oil socked areas..

I talked a while with a guy who'd done a lot of spray welding to build up shafts. He said that even fingerprints would interfere with adhesion of the applied material. To do a shaft, he first did a clean-up cut to fresh, clean metal, then set up his spray rig

[RussZHC]

This link from the "Too Long Stock..." thread, http://www.practicalmachinist.com/vb...e-shop-220616/ is about one person's shop and IIRC, there is quite a bit about spray welding [you will have to dig a bit the thread is now 58+ pages} and he seems to have got it down quite successfully.

[cuemaker]

How long has the outfit been using flame spray to rebuild machines? Do they have an established reputation? Will they offer any references? Check them out, they could be a viable solution to your issues.
Rex

To be a bit clearer, I am not looking for repair work for this machine....

The shop I call is perhaps the preeminent shop for rebuilding these particular machines.

About oil and clean surfaces.... The gentlemen said that its one of the benefits of heating the cast iron to orange hot, it clears the oil and grease out...


I was more thinking about regrinding an old lathe and then how to account for loss of material...

[flylo]

Cuemaker, how much did this save over replacing the part new? It can save a fortune instead of buying a complete new, crank, shaft, etc. I even have ceramic powder. There is an association for it but they're very tight lipped about it unless you're a member.