Fixing a broken brass saw bolt?

[sploo]

This evening I was taking an old saw apart in order to clean it up, and some eejit* managed to snap one of the brass saw bolts

I think that one of the sets here (https://www.fine-tools.com/make-your-own-saw.html) would probably work as a replacement, but is there any hope of repairing the bolt? I have a blow torch and some lead free solder, but I assume that wouldn't be strong enough?

* Yes, me

 

[woodbrains]

Hello,

No, soft solder wouldn't be strong enough. Hard solder is too high a MP to solder brass, without melting it. I would cut the stub off the head and drill a suitable sized hole in it. Square up the hole with a needle file and fit in some new brass rod, with a suitable square filed on the end. Rivet over and file flush, perhaps run in some CA glue too, then cut a thread on the new brass rod.

This is assuming you have thread cutting dies etc.

It might be you'll have to wait for a donor saw.

Mike.

 

[sploo]

Thanks. I don't have an imperial die that's small enough but I'm sure I could find one. That said, once the cost/time of the brass rod and die is taken into account it might just make sense to buy the replacement parts from fine-tools.

 

[bugbear]

This is one of the reasons it is generally recommended NOT to take old split nut saws apart...

The other is that the threads are very shallow and soft, so the nuts prone to slipping.

BugBear

 

[sploo]

This is one of the reasons it is generally recommended NOT to take old split nut saws apart...

The other is that the threads are very shallow and soft, so the nuts prone to slipping.

BugBear

Now you tell me

TBH There was a fair bit of rust on the plate underneath the handle so I'm doing my best to convince myself that being able to fix that issue was worth the screw up with the bolt.

 

[bugbear]

Hello,

No, soft solder wouldn't be strong enough. Hard solder is too high a MP to solder brass, without melting it. I would cut the stub off the head and drill a suitable sized hole in it. Square up the hole with a needle file and fit in some new brass rod, with a suitable square filed on the end. Rivet over and file flush, perhaps run in some CA glue too, then cut a thread on the new brass rod.

This is assuming you have thread cutting dies etc.

This is assuming that the thread in the nut is anything like a standard thread...

BugBear

 

[woodbrains]

Hello,

No, soft solder wouldn't be strong enough. Hard solder is too high a MP to solder brass, without melting it. I would cut the stub off the head and drill a suitable sized hole in it. Square up the hole with a needle file and fit in some new brass rod, with a suitable square filed on the end. Rivet over and file flush, perhaps run in some CA glue too, then cut a thread on the new brass rod.

This is assuming you have thread cutting dies etc.

This is assuming that the thread in the nut is anything like a standard thread...

BugBear

Hello,

This is assuming that anyone would undertake these restorations without having an entire machine shop and forge at their disposal? These things are bound to happen!

Mike.

 

[AndyT]

I've got one spare which may well be identical. If I can find it, you're welcome to have it. I hope you're not in a rush.

 

[sploo]

Hello,

No, soft solder wouldn't be strong enough. Hard solder is too high a MP to solder brass, without melting it. I would cut the stub off the head and drill a suitable sized hole in it. Square up the hole with a needle file and fit in some new brass rod, with a suitable square filed on the end. Rivet over and file flush, perhaps run in some CA glue too, then cut a thread on the new brass rod.

This is assuming you have thread cutting dies etc.

This is assuming that the thread in the nut is anything like a standard thread...

BugBear

Given that it's an old British saw it'll likely be 1/8th of a fathom with a left-handed hogshead 27.38tpi reverse thread

 

[sploo]

I've got one spare which may well be identical. If I can find it, you're welcome to have it. I hope you're not in a rush.

That would be awesome, many thanks.

The nut is about 14mm in diameter, with the bolt about 24mm overall length.

 

[AndyT]

Just to say, my saw bolt is only 20mm and isn't the answer to sploo's problem, so if anyone else can help with a longer one, or needs a short saw bolt, please say.

 

[sunnybob]

If there are any welding shops around you can braze brass. Many moons ago I used to braze brass bands to be turned into ships clock and barometer glass bezels. But you would need to be able to recut the thread afterwards.

 

[liamscanlan]

I may well be missing the point.... and I realise there is appeal in originality, but it wouldn't be difficult to turn a new nut and screw for this - or buy one from Matthew at Woodworker's Heaven? If you can provide dimensional drawings, I'd be happy to try to replicate the originals (when the thread pitch becomes irrelevant)... just let me know if I can help - or tell me I'm missing the point.
Liam

 

[D_W]

Daryl Weir had a write-up online somewhere about fixing these with silver solder. I see above that it's suggested it won't work, but he's been doing it for a while and I had success doing it less neatly than he does it. Not saying it's ideal, just that it can be made to work on most nuts.

I don't remember if Daryl posted it on woodnet (if he did, it's long gone because they don't archive posts), but I can't find it on google.

 

[Cheshirechappie]

Silver solder (given careful choice of grade) works for brass, brazing does not because the temperature required to melt the braze also melts the workpiece if it's brass. That's because braze (sometimes called 'spelter', especially in older sources) is actually brass!

 

[RogerP]

Sometimes slotted knurling brass binding screws and posts will work okay. Try eBay.

 

[sploo]

I may well be missing the point.... and I realise there is appeal in originality, but it wouldn't be difficult to turn a new nut and screw for this - or buy one from Matthew at Woodworker's Heaven? If you can provide dimensional drawings, I'd be happy to try to replicate the originals (when the thread pitch becomes irrelevant)... just let me know if I can help - or tell me I'm missing the point.
Liam

The point is that I'm being a bit tight

There's a replacement version available from Fine Tools (actually a Blackburn Tools USA product: http://www.blackburntools.com/new-tools ... index.html) that should just about fit OK, and would look "original". The problem is that a pair would cost basically what I paid for the saw - so perhaps not the best sense in economic terms.

Matthew's version is aesthetically different unfortunately - though much cheaper. I'd also have to drill the saw plate and handle as the thread is much fatter.

Having said all that, I'm relatively new to restoring saws, and so far it seems that the domed saw nut style (like Matthew's, and indeed most Disstons) seems to be much more robust than the ones on this saw.

I'll probably have a go with some solder or epoxy, and once I've sorted the plate and handle I'll try putting it back together. Once I inevitably snap the bolt again I'll have to decide on an solution

 

[liamscanlan]

Well, I am happy to try and I don't want payment! How cheap is that? Just let me know.
Really - if I can help it would be my pleasure - just send me some dimensions
Liam

 

[sploo]

Well, I am happy to try and I don't want payment! How cheap is that? Just let me know.
Really - if I can help it would be my pleasure - just send me some dimensions
Liam

That would be awesome - thankyou.

I'll take some measurements and post - hopefully tomorrow. I don't know what the thread is (I was hoping it might be UNC, but I don't have a UNC tap or die that small in order to test the thread).

 

[ColeyS1]

Was the snapped bolt off a disston tenon saw ?

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