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Cliff Rohrabacher
02-07-2008, 11:05 AM
Having figured that I prolly can cut my own teeth on a .010" thick by 6" or 8" length of card scraper stock and then make an d mount a handle to it. I am wondering how I might make the back.

I have lots of carbide drills so drilling the hardened steel wouldn't be an issue.

The one option that stands out in my head is to make it from solid bar stock (steel or brass) drilling and tapping it and simply screwing that to the card scraper.

Any one done this - made a back saw? How'd you go about it?

Pedder Petersen
02-07-2008, 11:21 AM
Hi Cliff,

due to the SMC-rules I'm not allowed to give a link. But there is a thread startet by Tim Hoff on Woodnet.net right now. He shows the making of a through drilled saw back. Very impressive.

Btw: take a back from an old saw is the easiest and cheapest method.:)


Cheers Pedder

Don C Peterson
02-07-2008, 11:39 AM
Cliff,

I ran across this a while ago, it seems pretty comprehensive and contains info on suppliers as well...

http://www.norsewoodsmith.com/node/68 There's also a PDF available from that page.

Robert Rozaieski
02-07-2008, 12:42 PM
I would think a folded back would be much easier for the home shop to make.

Michael Faurot
02-07-2008, 1:00 PM
Any one done this - made a back saw? How'd you go about it?

Your idea to convert a scraper to a saw sounds interesting. I'll be curious to see what you come up with for making the back.

When I made my own, what I did was to take the backsaw blade that came from a $5 K-Mart "nest of saws". I then cut off the part that was designed to fit into the original hangle and then made my own open grip style handle. Based on the location of the holes in my new handle, I then drilled new holes into the blade to attach the handle. From there it was just a matter of removing all the set, jointing the teeth and then filling it to a rip pattern.

Tony Zaffuto
02-07-2008, 2:15 PM
IIRC some have made saws from drywall taping knives that are readily available at your local borg. Lengths go from 4" through 12". Tim Hoff's method of using epoxy to fit two pieces of brass on each side of the saw plate looks interesting enough to launch a whole bunch of guys (and gals) trying their hand at saw making. His pictures are posted on Woodnet.

T.Z.

Cliff Rohrabacher
02-07-2008, 4:24 PM
Hi Cliff,

due to the SMC-rules I'm not allowed to give a link. But there is a thread startet by Tim Hoff on Woodnet.net

Thanks That's a nice thread.

Cliff Rohrabacher
02-07-2008, 4:29 PM
I would think a folded back would be much easier for the home shop to make.

Tell me Tell me. I am all ears~!! I used to be a machinist toolmaker years back. I still have a lot of tools so small scale metal work is not an issue for me. Tons of taps, drills, C-sinks, end mills and other cutting tools - you name it.

However, bending the brass back into a nice straight U channel and compressing it onto a blade seems a tad beyond what I imagine I can do.

How would you set about to do it?

Cliff Rohrabacher
02-07-2008, 4:39 PM
Cliff,

I ran across this a while ago, it seems pretty comprehensive and contains info on suppliers as well...

http://www.norsewoodsmith.com/node/68 There's also a PDF available from that page.

Printing the PDF even now thanks

Cliff Rohrabacher
02-07-2008, 5:47 PM
Thanks
You guys are a big help.
The way the Norse Woodsmith guy mounts his sure is a beast of a job. Easy to get the thing bent I'd guess. I may try it but I wonder if screwing it together - or epoxy - or both wouldn’t be better easier faster cleaner and of course straighter.
Total enclosure in a U channel is more rigid. But, how rigid does it need to be?



Tempered steel Taping knives is a source I hadn't thought of.
From the Mc Master Carrr site I have these

Hardened & tempered Steel for blade
#9014K24 $13.51

Brass Flat stock for making to back ridge 12” *12"* 0.930 thick 8956K42 $47.70

Brass Bar stock (for making the fancy nuts and bolts)
5/8” Dia x12” 8970K581 $14.39
For some reason you pay a lot more if you want a length other than 12”

So far the total is $75.60

A factory new Gramercy is a little over $139.00
The Gramercy Kit with a sharpened blade is $69.95

Buying nice flat mild steel stock isn’t a whole lot cheaper than the brass.

I wonder if the Borg won’t have flat steel cheaper.

Gotta check, dropping nearly $50.00 from the total would make a difference. Go ahead: Call me cheap.

Robert Rozaieski
02-08-2008, 8:15 AM
Tell me Tell me. I am all ears~!! I used to be a machinist toolmaker years back. I still have a lot of tools so small scale metal work is not an issue for me. Tons of taps, drills, C-sinks, end mills and other cutting tools - you name it.

However, bending the brass back into a nice straight U channel and compressing it onto a blade seems a tad beyond what I imagine I can do.

How would you set about to do it?

One could use a break to bend the brass and a mallet or soft wood bat to tap the blade home. Backs were traditionally folded with the baldes friction fit. I'm not a machinist or a metal worker but I have used a break before and it wasn't hard to get a nice straight bend. Granted I was bending aluminum but I would imaging brass shouldn't be that much harder given the right break, considering folded backs were the norm for backsaw production since the backsaw's inception, well before the advent of modern machining tools.

Maybe Mike W. will chime in as to how they fold backs for their saws. Check Joel's Tools for Working Wood website for instructions on how to put together the Grammercy Tools Dovetail Saw Kit. The instructions go through how to fit the blade to the folded brass back. Lief has instructions for bending backs using a shop built break on his Norse Woodsmith website. Doesn't seem to hard to me, just to get some angle iron to build the break.

Cliff Rohrabacher
02-08-2008, 9:35 AM
One could use a break to bend the brass and a mallet or soft wood bat to tap the blade home.


Quite so. There is a shop built angle iron break used in the Norse Woodsmith's PDF on this very topic. He does end up hand hammering it afterward. Clearly I have not contemplated such a direct approach. In my mind's eye I had the bending process and then a high pressure compression of the brass onto the blade after the blade was inserted. I saw that - of a necessity - taking place as a one shot operation along flat parallel plated in a press.

The application of hammer blows is a way to also do it. I wonder how long it took the Norse Woodsmith guy to learn how not to warp or bend the saw blade?
Gentle, gentle, gentle is prolly the order of the day.

Tim Leo
02-08-2008, 10:54 AM
The application of hammer blows is a way to also do it. I wonder how long it took the Norse Woodsmith guy to learn how not to warp or bend the saw blade?


I have a Norse Woodsmith saw. I think it is harder [to not warp or bend the saw] than you imagine.

Leif Hanson
02-08-2008, 12:54 PM
It's not all that hard to bend the back... or to hammer it home. It took me a couple tries to get it right though... That article is a bit dated, as now I use a hydraulic press which takes all the hammer work out of it.

I haven't made a saw in a while, now - but I still have the brake I made, and can still use it after having made a couple hundred saws with it, though it is showing it's age.

There is a bit of a knack to straightening the blade straight when hammering it. Still - it's not that hard to do. But if it concerns you, then Tim Hoff's method in the Woodnet post is perfectly viable - he has made some excellent saws that prove it. The only other method is to use a slitting saw in a mill to cut a slot in the back.

I believe Mike Wenzloff has slots cut in most of his backs these days, but has done some folded backs. (Edit - slots are how Independence tool made their saws and consequently how Lie-Nielsen's are made - and I believe Adria as well). We communicated pretty extensively when he was first starting up and wondering which way he would go with how to manufacture the brass... When he did/does, he has/had a machine shop do the initial bend, IIRC., then either hammers (originally) or presses (he must have a hydraulic press by now) the brass home. He may do his own slitting by now, too...

Leif
www.norsewoodsmith.com (http://www.norsewoodsmith.com)

Robert Rozaieski
02-08-2008, 1:24 PM
I believe Mike Wenzloff has slots cut in most of his backs these days, but has done some folded backs. (Edit - slots are how Independence tool made their saws and consequently how Lie-Nielsen's are made - and I believe Adria as well). We communicated pretty extensively when he was first starting up and wondering which way he would go with how to manufacture the brass... When he did/does, he has/had a machine shop do the initial bend, IIRC., then either hammers (originally) or presses (he must have a hydraulic press by now) the brass home. He may do his own slitting by now, too...

Leif
www.norsewoodsmith.com (http://www.norsewoodsmith.com)

The Kenyon saws that Mike makes have folded backs (at least that's what the description says). I don't know about the other saws he makes.

Don C Peterson
02-08-2008, 1:36 PM
Quite so. There is a shop built angle iron break used in the Norse Woodsmith's PDF on this very topic. He does end up hand hammering it afterward. Clearly I have not contemplated such a direct approach. In my mind's eye I had the bending process and then a high pressure compression of the brass onto the blade after the blade was inserted. I saw that - of a necessity - taking place as a one shot operation along flat parallel plated in a press.

The application of hammer blows is a way to also do it. I wonder how long it took the Norse Woodsmith guy to learn how not to warp or bend the saw blade?
Gentle, gentle, gentle is prolly the order of the day.

I've never made a back saw, but I have rehabbed a few that needed to have the backs removed. I was initially afraid to undertake this at first, but using wooden blocks and a deadblow mallet it wasn't that hard to either remove the back or put it back on without damaging the back or the blade. A sturdy vise and some patience is required, but it really wasn't that bad.

Michael Fross
02-08-2008, 5:28 PM
So far the total is $75.60

Gotta check, dropping nearly $50.00 from the total would make a difference. Go ahead: Call me cheap.
Great post. I appreciate the numbers.

I've been really wanting to do this for some time, shortly after read the norsewoodsmith web site.

Don't forget, however, that this material list will allow you to make two or three saws, not just one.

Michael

Cliff Rohrabacher
02-08-2008, 8:14 PM
Great post. I appreciate the numbers.

I've been really wanting to do this for some time, shortly after read the norsewoodsmith web site.

Don't forget, however, that this material list will allow you to make two or three saws, not just one.

Michael

materials for 3 or 3 might be enough to get one.