Thread: Saw Making Folded Backs

Nice find there Dale
What I like the most is he is just doing it
Not just gasbaging and discussing minor points
Just doing

Kees doesn't post here?!! I thought he posted everywhere!

Originally Posted by DSEL74

Here is a link to a blog where the fella makes his own folded backs for those interested in alternative ways. In my opinion a tough job to keep the slot straight.

You're not wrong there, Dale. I cast about for ways to fold some backs many years ago. I tried folding a piece of 1/8th plate, and found the alloy I had would not go past about 75 degrees of bend without breaking. As I didn't have the means to keep annealing a full spine's worth during the bend, I gave the idea away, & my saw making lapsed for many years, until a friend offered to slit some bar for me with his thumping great milling machine. Posting the result of that effort on the Forum led to Mr. G., who encouraged me to think about slotting my own with some pretty simple gear, and that was the beginning of my saw affliction.....

As I've said several times, slotted backs appeal to me as the most practical way to go for amateur builders or even small-scale production. It's far easier to get a straight spine with a straight slot in bar stock with quite a basic setup, than you can achieve by folding, unless you have a decent panbrake, & even if you have that, you still need soft alloy that will take the bend(which is simply not available round my neck of the woods). The bloke in the article you linked to is having a heck of a time keeping the blades straight while getting his spines on - partly because they are too tight, & partly, I suspect because hammering the metal flat has caused all sorts of uneven pressure along the fold. I aim for a firm press fit that taps on fairly easily. So far I haven't hand one rattle or fall off, & they are a lot easier to get on the blade without distorting it!

Cheers,

Toby made me aware of this thread. So I'd say, Hello ! I am the bloke who made the saws.

In the grand scheme of things, I also think slotting a spine is easier. But I've never done it, so I am not sure. Because I want to make my copies of old English saws as authentic as possible, I really wished to make a folded spine.

BTW, I use brass with 63% copper (M 63). It's advertised as being half hard. I had no problem with breakage at all.

Welcome my friend, glad to see you here! Friendly knowledgeable people on this forum. yellowyes.gif

Hi Corneel, come join the fray! We welcome all approaches to saw making here. If making copies of old saws is your thing, then of course, folding backs would be de rigeur. For someone making a couple of saws, I think slotting bar stock is easier, but of course, non-traditional.

I only wish I could buy soft alloys easily here, not so much for making saws, but for other jobs like making planes. The only alloy readily available to me is 57-59% Cu, with some lead and smidgin of Aluminium, the rest Zn. It's not good for folding or peining. This is what they tell us on one website:
"Alloy 380 Section Brass is a copper-zinc-lead alloy with a small addition of aluminium, having a duplex phase structure with a fine dispersion of lead particles. It has good machinability but limited cold forming properties and is generally supplied as extruded." .... My italics, but they ain't wrong there!

Cheers,

Originally Posted by Corneel

Toby made me aware of this thread. So I'd say, Hello ! I am the bloke who made the saws.

In the grand scheme of things, I also think slotting a spine is easier. But I've never done it, so I am not sure. Because I want to make my copies of old English saws as authentic as possible, I really wished to make a folded spine.

BTW, I use brass with 63% copper (M 63). It's advertised as being half hard. I had no problem with breakage at all.

Thanks for coming to the forum. Feel free to share your further work here.

Welcome also to the forum Kees. Please feel free to post photo's of your latest backsaw. I am sure it will add some valuable inspiration to our forum members who are just starting down the road of saw making..

Stewie;

I've got a question for you guys. When folding and hammering my brass backs I use a temporary 0.3 mm thick steel plate instead of the target 0.5 mm plate. Thus the back is squeezed a little tighter. But I'm starting to think this is overkill, and I can just as well use the 0.5 mm plate while hammering. How are your thoughts about this?

Originally Posted by Corneel

I've got a question for you guys. When folding and hammering my brass backs I use a temporary 0.3 mm thick steel plate instead of the target 0.5 mm plate. Thus the back is squeezed a little tighter. But I'm starting to think this is overkill, and I can just as well use the 0.5 mm plate while hammering. How are your thoughts about this?

Corneel - on most old saws I've pulled apart, the backs were firm, but certainly not tight to the point they needed heavy bashing to get on & off. So when fitting backs, I aim for a similar fit, that requires tapping to get it on the saw, but certainly not heavy hitting. With the slit backs like I use, it's pretty easy to get the fit just so by squeezing the back in a vise. You can close it up very evenly this way & regulate the tightness of fit quite closely. I don't see why that wouldn't work with folded backs, if you folded onto slightly oversize plate, you could then sneak up on the desired fit by squeezing it up a fraction more....

Cheers,

Yep, that's a good idea. Mine are now a bit too tight probably.

I tried another thing. Pressing my name stamp into the spine. No idea how they did that in the old days, but it warps the back considerably and makes for an extensive rebending and finetuning session again. I think it is smarter to use a laser engraving service if I want my name on the back.

Originally Posted by Corneel

I've got a question for you guys. When folding and hammering my brass backs I use a temporary 0.3 mm thick steel plate instead of the target 0.5 mm plate. Thus the back is squeezed a little tighter. But I'm starting to think this is overkill, and I can just as well use the 0.5 mm plate while hammering. How are your thoughts about this?

Hi Corneel. From watching your short video on your website, I agree with you that the 0.5mm target size would be a better option to use. It should not require that much exertion to fit the folded back onto the saw plate.

Originally Posted by Corneel

Yep, that's a good idea. Mine are now a bit too tight probably.

I tried another thing. Pressing my name stamp into the spine. No idea how they did that in the old days, but it warps the back considerably and makes for an extensive rebending and finetuning session again. I think it is smarter to use a laser engraving service if I want my name on the back.

Corneel,
they probably stamped it with a screw fly press, and did it before the folding over.
...at least that's how I have done it.
I don't have a picture of the press with a saw back, but I do have a picture of the press when I put my mark in a plane lever cap. On that one I used hard brass, and did it red hot, on soft brass, it doesn't need the heat.
Regards,
Peter

Corneel,
they probably stamped it with a screw fly press, and did it before the folding over.
...at least that's how I have done it.

Very sound advise Peter.