Cast Iron while its out for repair should I redo this braze?

[woodchucker]

I am sending this out to a kid who did an excellent weld (not braze) on my 8520 brake. I asked him to weld it if he could with nickel as an old time welder told me nickel. He heated it and welded it.. beautiful.

Now I bought this taper attachment, I probably shouldn't have as it has so many issues. It was cracked and brazed , and was being offered for less. It looked good enough to use, but it had cracked ways on the dovetails. I ground out the old studs and damaged area, since I want to fix and get new grub screws in there. Whoever did the repair used small grubs and relocated them. That didn't bother me, but the cracks did. So while he is doing the ways, should I have him redo the previous crossslide repair. It looks like copper based, not silicone bronze, as I would have expected. Once I took the paint off, I was bothered by the color.

The funniest thing, the pic in this http://www.lathes.co.uk/south-bend-boxford-taper-unit/ is the unit before the break that was repaired. So this may have made it's way from the UK. The unit is awful. I should not have bought it. But now it has to be turned into a user, as I can't pawn it off on someone else.

I have more cleanup to do, just finished stripping it.

 

[wawoodman]

If you have a guy who will do it well, go for it. Otherwise, it will **** you off every time you look at it. Even if no one else would notice, you will.

 

[markba633csi]

It looks like it should have some additional "sister" pieces of steel or iron brazed in on both sides of the cracked area to give it more strength, it seems very likely to break again in that same area unless you do some heroic measures. Better to go for the maximum strength and to heck with keeping it looking stock. My two cents.
Mark S.

 

[Ulma Doctor]

make lemonade from lemons, if you can.
alignment of the broken parts will be tricky to maintain, but if the guy welding it up is competent- he can stick it back together again.
i'd like to see the finished repair

 

[cathead]

I would like to have been the fly on the wall watching the operation that broke that part. There isn't a huge force exerted on
the part in use as far as I can see. Also, when making tapers the feed is slow and depth of cut is small. I would run it and see how
it works as is and fix it if would happen to break again. Looking at the repair it looks it could be welded with cast iron rod
and touched up with copper or brass afterwards. I have seen brazing that looks like copper if the zinc boils off some leaving an alloy
with more copper behind. It's your machine so you can do as you please of course. I find it quite interesting when a group looks
at the same post and a wide range of cogitation comes to light. You mention cracked ways on the dovetails which would be more
of a concern to me than the repair as that would likely affect linearity. Anyway, now you have another angle to ponder.

 

[Rustrp]

The part looks like it may have been TIG welded because an oxy/acety brazing job wouldn't cause undercut on the edges. The problem with using Ni based electrode (before I go and say I would use Ni) on this part is the removal of all the bronze. It must be removed, otherwise leave it, clean it up, reinforce it, etc.

For a non-machinist I would weld it up with nickle based electrode and finish it as close to dimension as possible. For the machanist I would use runoff tabs to help keep the part straight and leave all the excess material on and allow the machinist to mill the excess off.

Welding cast iron is all about good days and bad days. The good days are those when the part doesn't have extra high carbon content in the area to be welded.

 

[4GSR]

If it was me, I'd buy a piece of rectangle cast iron the right length and make a complete new slide. Wouldn't take much provided you have a mill and the appropriate tooling which I have. I don't need another project....

 

[scwhite]

I would like to have been the fly on the wall watching the operation that broke that part. There isn't a huge force exerted on
the part in use as far as I can see. Also, when making tapers the feed is slow and depth of cut is small. I would run it and see how
it works as is and fix it if would happen to break again. Looking at the repair it looks it could be welded with cast iron rod
and touched up with copper or brass afterwards. I have seen brazing that looks like copper if the zinc boils off some leaving an alloy
with more copper behind. It's your machine so you can do as you please of course. I find it quite interesting when a group looks
at the same post and a wide range of cogitation comes to light. You mention cracked ways on the dovetails which would be more
of a concern to me than the repair as that would likely affect linearity. Anyway, now you have another angle to ponder.

I would like to go back to when and where it got Broke also and if I was guessing and I am guessing
But in my opinion it most likely got broke while someone was trying to move the machine or load it in a truck or trailer or unload it . Moveing machinery
Is the most common way that cross feed screws and hand wheels . Gear box handles , tail stock hand wheels get bent or broke .
Just plain under tooled to move the machine
Properly.

 

[woodchucker]

Or it could have been during shipping of the part. I don't believe it is an original South Bend as originally advertised either. There's no SB label, no SB part no.
It looks like a knock off that someone did up. The cast iron, is not the same granularity of other SB cast irons. This has a very smooth finish, and was not machined where SB would normally machine things. The paint covered a lot of those issues. That paint was pebbly and tough stuff to remove. There were enough screws and the gib plate that were rusted, or pitted. I don't see wearn (nothing is smoothed from wear) , so this may have never been used, and may have been dropped while handling. For it's lack of use, it's in rough shape.

 

[4GSR]

Or it could have been during shipping of the part. I don't believe it is an original South Bend as originally advertised either. There's no SB label, no SB part no.
It looks like a knock off that someone did up. The cast iron, is not the same granularity of other SB cast irons. This has a very smooth finish, and was not machined where SB would normally machine things. The paint covered a lot of those issues. That paint was pebbly and tough stuff to remove. There were enough screws and the gib plate that were rusted, or pitted. I don't see wearn (nothing is smoothed from wear) , so this may have never been used, and may have been dropped while handling. For it's lack of use, it's in rough shape.

It's definitely South Bend. Unless someone bought it thinking it is SBL and actually from a Dalton lathe, but I don't think so. I had a 9" SBL I reconditioned that had the taper attachment, it had this same cross slide piece. Fortunately, it was in decent shape and not broke up and butchered as this one is.
If your not in a rush, I'm sure they come up on ePay often, buy one to replace this one with. Will require some scraping and fitting to get it right for your lathe. Ken