Help for a friend....

[slim_boy_fat]

A good friend has an old but fully functional mechanical hacksaw which he recently knocked over and broke a cast part of .

He's a retired craft/technical teacher so usually knows his stuff. He decided he'd braze it back together using his oxy/propane gear [no O/A available] with the appropriate rods but didn't have any success.

So he decided after online research that TIG with the necessary rods would do the job, although I had reservations.

Anyway, we arranged a visit and he had a go with my TIG setup, and I was right in that he couldn't make it work [I was having nothing to do with the job other than turning the Argon on and off, in case I effed it up ].

I suggested getting the appropriate MIG wire for cast, but he took it home to try again.

This is what he's faced with, the only good thing is the break was clean and straight across, the 'bite' out of the upper surface seen in the second pic was a result of the TIGing effort......

All he has at his disposal other than the oxy/propane is a very old arc welder with limited capability.

So, how to proceed? He's said that if he can't effect the repair he'll just scrap the saw, but that seems a shame because modern ones won't have the same quality/capacity at a reasonable price - and besides that I hate to see a good machine dumped.......

 

[Shox Dr]

Stainless rods. Preferably 312.

Although I welded up a vice for a mate over 8yrs ago, with 316. it's been beaten ever since, still going strong

 

[Shox Dr]

Or SiF No8/968

 

[slim_boy_fat]

I have stainless 316 rods which I got from @eSCHEn but my pal brought his rods with him - perhaps they were the ones he had for brazing, never thought to ask but I assumed they were the ones he was sure would work Anyway, maybe my 316s wouldn't have worked.

Would the MIG wire not do the job using my R-Tech 180?

 

[Shox Dr]

By the look of the white soot, they are gas rods.

 

[slim_boy_fat]

If he feels the need to ditch it I'm going to have it over here to have a go - nothing ventured, nothing lost, and even I can't make things any worse than the skip.....
But I'd love to see it properly fixed.

 

[bigegg]

Id be tempted to use the old part as a pattern, and cast a new one from wheelium.
(alloy wheel aluminium)

 

[brightspark]

that's a bummer because it runs on the taper slides. it would braze up ok using oxy acet but u would need to heat round the job with a decent propane torch as well to keep the heat up

 

[slim_boy_fat]

that's a bummer because it runs on the taper slides. it would braze up ok using oxy acet but u would need to heat round the job with a decent propane torch as well to keep the heat up

I recall him saying something about tapers. I meant to phone him today to check on progress but life [in the shape of a car service in scorching heat] got in the way.

 

[slim_boy_fat]

Just to put this to bed, I phoned him this afternoon and he got it brazed back together this morning, using 'borrowed' access to OA gear.

Saw now reassembled and working again - he's a happy bunny and will be more careful in future when he's moving stuff around in the garage.

Once again, the input is appreciated, lads.