Thread: Saw making, Bladeslot and fitting in the spine

Thankyou, Klaus. I sometimes start the slot with a slitting saw, too. If I am doing several handles, I use the slitting saw, but for a single handle, I usually can't be bothered setting up the saw, so I will make the whole slot with a hand-held saw. However, my slitting saw setup is very crude compared with yours, just the saw chucked in my drill-press. (It looks rather scary, too, so I'll not make it public. ).

One reason I asked how you made the slot was because in one picture I saw, the oval spine appeared to continue in a perfect fit into the handle, but I think it was my eye being tricked, because as you clearly show, the handle part of the spine remains un-shaped, apart from the little step. I like to put a bold chamfer along the bottom edge of the spine, which causes some trouble when fitting. I have tried stopping the chamfer when it reaches the handle, and shaping the bottom of the handle slot to accommodate the chamfer, & it is tricky to get a really seamless fit either way. I have noticed on old saws that the slot for the spine is often quite roughly made. That may not affect performance, but I try to do as good a job of it as I can!

Cheers,

Thanks Klaus, a very nice breakdown. We will have all your secrets soon.

Look forward to part 2, shaping and polishing the spine.

Thanks Klaus, nice simple setups, and not too much heavy machinery, just a good use of a drill press and electric drill. ... How are you slitting the brass?

You might like to know, that it was one of your saws that inspired Dale to organize the backsaw making workshop, so you can take a bow.


Regards
Ray

PS. It was the ebony handled one.

A very detailed post full of high quality information Klaus. Thank you. A great source of inspiration for our up and coming saw makers to what can be achieved given the right mind set. The mortise fit on your backsaws are the best I have seen by far. We are indeed most fortunate on this forum site to have such experienced saw makers as yourself, Isaac, & Marv, willing to share their knowledge & experience in an effort to assist up an coming saw makers learn this craft. A most generous gift.

Stewie;

Originally Posted by IanW

I like to put a bold chamfer along the bottom edge of the spine, which causes some trouble when fitting. I have tried stopping the chamfer when it reaches the handle, and shaping the bottom of the handle slot to accommodate the chamfer, & it is tricky to get a really seamless fit either way. I have noticed on old saws that the slot for the spine is often quite roughly made. That may not affect performance, but I try to do as good a job of it as I can!

Hi Ian,

to me it's less tricky to stop the bottom chamfer of the spine than to shape the slot bottom of the handle according to the chamfer shape. Indeed I agree, that the fitting in of the spine on vintage saws often was made sort of crude. But one thing the former saw makers did always perfectly. That's the parallelism between blade slot and spine mortise. You hardly will see a vintage backsaw with a bow in the blade beneath the cheeks (aside the saw was damaged of course).

I like a proper connection between spine and handle because it shows some of the pride from the maker that went into the tool.

Cheers
Klaus

Originally Posted by DSEL74

Look forward to part 2, shaping and polishing the spine.

Hi DSEL,

the shaping of the spine is easy. Just remove all the parts from the brass blank that you don't like with a file. The rest will be the part of the brass that you like

Cheers
Klaus

Originally Posted by RayG

Thanks Klaus, nice simple setups, and not too much heavy machinery, just a good use of a drill press and electric drill. ... How are you slitting the brass?

You might like to know, that it was one of your saws that inspired Dale to organize the backsaw making workshop, so you can take a bow.


Regards
Ray

PS. It was the ebony handled one.

Hi Ray,

nice to hear from you.

Our brass backs will be slitted by a machinist on a CNC mill. He uses carbide saw blades in different widths to do that. Since this man makes the slots in this way, we never had one less than perfect spine blank again.

It makes Pedder and me very proud that the dovetail saw we made for you was that inspirational. Wow!

Cheers
Klaus

Originally Posted by planemaker

A very detailed post full of high quality information Klaus. Thank you. A great source of inspiration for our up and coming saw makers to what can be achieved given the right mind set. The mortise fit on your backsaws are the best I have seen by far. We are indeed most fortunate on this forum site to have such experienced saw makers as yourself, Isaac, & Marv, willing to share their knowledge & experience in an effort to assist up an coming saw makers learn this craft. A most generous gift.

Stewie;

Thank you, Stewie!

Klaus

Originally Posted by KlausK

.....I like a proper connection between spine and handle because it shows some of the pride from the maker that went into the tool....

Absolutely. I could not agree more. With respect to older saws, I sometimes wonder if the loose fitting of the spine wasn't deliberate, so that there would be less chance of distortion after tightening the bolts, caused by mis-match of the respective slots.

I have seen a few old saws with bowed blades caused by less-than-perfect fitting of their handles - there have to be a few that escape QC, I suppose.

Originally Posted by KlausK

.....the shaping of the spine is easy. Just remove all the parts from the brass blank that you don't like with a file. The rest will be the part of the brass that you like...

Seems like you read the instructions on 'how to make a chair', that I saw somewhere, years ago. It was the same, essentially. "Take several pieces of wood, knock off the bits that don't look like a chair, then stick what is left together until it does..." Probably dates from pre-historic times.

Cheers,

Great work Klaus, that is a lot of dedicated file work, and W & D paper, and polishing (I assume on a power polisher). After filing small chamfers, I decided I liked square.

Is the drill press a standard commercial product, or a custom job. I have never seen anything as robust, or flexible, as this for a drill.

Cheers
Peter

Originally Posted by IanW

Absolutely. I could not agree more. With respect to older saws, I sometimes wonder if the loose fitting of the spine wasn't deliberate, so that there would be less chance of distortion after tightening the bolts, caused by mis-match of the respective slots.

I have seen a few old saws with bowed blades caused by less-than-perfect fitting of their handles - there have to be a few that escape QC, I suppose.



Seems like you read the instructions on 'how to make a chair', that I saw somewhere, years ago. It was the same, essentially. "Take several pieces of wood, knock off the bits that don't look like a chair, then stick what is left together until it does..." Probably dates from pre-historic times.

Cheers,

Hi Ian. I think Klaus is not quite reflecting the amount of high end work that goes into producing the mirror finish they can achieve with their shaped backs. With less care taken, they can look not so appealing. IMO.

Stewie;

Originally Posted by KlausK

Hi DSEL,

the shaping of the spine is easy. Just remove all the parts from the brass blank that you don't like with a file. The rest will be the part of the brass that you like

Cheers
Klaus

Hi Klaus.. You will pleased to know I have following your lead and have completed a haunched mortise fit to the brass back & handle on the burdekin plum backsaw build. It will also become a dt but differ in that it will have a much lower hang angle so the controlling hand is more behind the stroke. Too early for photo's yet.

Stewie;

The spine filing is easy but time consuming. I work about 3 hours to this point:
IMG_0191.JPG

Cheers
Pedder

Originally Posted by pedder

The spine filing is easy but time consuming. I work about 3 hours to this point:
IMG_0191.JPG

Cheers
Pedder

My apologies Pedder. I have forgotten to mention the important role you have in producing these fine quality backsaws. It looks like I will be spending some hours trying to shape the brass hardback similar to your technique.

Stewie;