Thread: Spear and Jackson hand saws

I have an old S & J rip saw. It's fantatic, the equal to the Disstons that I have. I don't know about new Pax saws, but can vouch for the old saws-I've never seen a bad blade, and the handles will be better than on the new saws too.

I had a discussion with a maker of high-priced boutique dovetail and tenon saws. I was asking about a custom sized handle, which he could not do. He told me to modify an old saw as they were 'as good' as his $150.00 saws.

Greg

The problem with new hand saws is that making a back saw is relatively easy, but a hand saw unsupported by a back needs both taper grinding and edge tensioning, both done largely by hand in the old factories and difficult to duplicate in a smal shop.



The best Atkins, Disston, Simonds and S&J saws were taper ground and around .00350 thick at the edge. The inexpensive saws like the D7 was .0042 or so at the edge. The difference was the thinner blade cut easier, but needed more tensioning and was accordingly more expensive. New ones by PAX or Roberts and Lee can cost 200 bucks and still be .0040 on the edge and no real improvement over a relatively inexpensive D7 or D8. The best of the old ones like the Disston 12, Disston Acme and Atkins 400 simply aren't duplicated today at all.

The good news is that rehabbing a hand saw isn't as difficult as the folks trying to sell you new saws like to make it out to be. I have a saw filing tutorial here if you search....and I'm writing a magazine article on total restorations this winter...to include retensioning.

Welcome back Bob - looking forward to it.

Dennis

Good stuff, Bob. If you can let us know when the article is ready and up, I would appreciate it.

The black art of tensioning.... gotta be good.

I have a Spear and Jackson "Workhorse" which I bought in the mid seventies.

It has none of the features Bob Alludes to, and was a relative cheapie at the time: $12.00 when I was earning less than $9k per year (It still has the price sticker on the cover).

It holds its edge well enough, but one can buy a saw of similar quality for less than the cost of having it sharpened by a service.

Cheers,

P

Great stuff Bob. Thanks.
I just measured a couple of my blades, and they are as you mention. I am amazed that this was done by hand. The Spear and Jackson 'Spearior 88" in the picture below is tapered teeth to back, and toe to heel. The teeth at the heel are 0.012" thicker than the toe.

I'm looking forward to your article.

Greg

BTW, the legend in the first photo reads:

"The Balance, Grip and Temper of this saw conforms exactly to a specification based on test reports from over 100 skilled carpenters"

New saws conform to something else.

This describes how the old hand saws were made:

http://www.disstonianinstitute.com/saw_works.html

Most of the hand work was in tensioning the saw...I'm sure the tapering was done on surface grinders, although hand-made Japanese saws are tapered even today using hand scrapers. But you're talking 300 bucks and up for that quality of Japanese saw.

As recent steel analysis shows no difference in the steel used in the various grades of Disston saw, it was the hand tensioning that allowed the thinnest blades and cost the most.

Hand tensioning a new saw from scratch like the Japanese smiths do it takes skill and experience, but repairing a kink by untensioning then retensioning the saw isn't difficult. If the saw ever kinked during a cut, it probably needs retensioning, and those mysterious small dents in old saws are often from mi&&&&s at the sharpening shop.

Striking the blade on an anvil causes a dimple that pulls the steel toward it a tad. The further you get from the dimple, the greater the tension caused, and the closer, the least. Dimples on one side without identical dimples on the other will cause the saw to pull to one side.



So the trick is uniformity. Mark both sides of the saw identically near the center of the blade, and alternate sides as you strike. For thin hand saws, a 6oz ball peen hammer is ideal. I used three raps per mark on this #12 blade, and I also rapped between my chalk marks. Some hammer in successive lines all the way from back to edge for max edge tension at the expense of back stiffness, but as I use saws often in awkward positions, I prefer more uniform stiffness with less danger of kinking.

If the edge is badly bent, then hammer a line close to the edge to remove all tension prior to straightening it....then work your way upwards after you hammer the kink out. You'll be much less likely to snap off a tooth that way.

Flex the saw prior to hammering to get a feel for how loose it is...hammer it as I describe...then flex it again and you should feel a difference. Be careful to keep the hammer face flat as you hit and you won't dent the saw.

Thanks Bob...I've got an old beater that was kinked when I bought it ($2.00). I'm going to attempt this tonight, just as soon as the neighbour's fool dog starts his nightly barking.

Do you take care to polish the hammer face, or just use it as it comes?
I don't have a 6oz, but I have a nice auto body hammer with a slightly domed face that I might try.

Greg

Originally Posted by gregoryq

I'm going to attempt this tonight, just as soon as the neighbour's fool dog starts his nightly barking.

Woof, Kadoink.
Woof, Kadoink.
Woof, Kadoink.
Woof, Kadoink.


Al

Originally Posted by ozwinner

.
Woof, Kadoink.


Al

I was thinking more of a gong sound, as heard in "The King and I". Oh, yeah. I just remembered that Bob mentioned an anvil. Won't that deaden the sound somewhat?:confused:

Drop the anvil on the dog and it'll deaden the sound

I read your post.....concerning the tensioning of handsaws and found it most interesting.

I have often heard passing mention of this subject but never really understood how it might be accomplished until I came upon your most clear and informative description. I am a regular user of handsaws and buy good quality old ones when they are available at the flea markets, which I then clean and sharpen and put to use.

Only last week, I had, as I thought, restored an old saw to good working
condition, having first hammered out a bend towards the toe, only to find that
the toe end of the blade rattled significantly on the backward pull stroke. I
tried correcting this by stoning the teeth but the rattling persisted. I should
therefore be grateful if you would inform me as to whether it is your opinion
that I should attempt to re-tension the blade in the manner described in your
post with the view to overcoming the rattle.

I noted in a later post by you that you referred to old-time saw doctors using a wooden anvil although, from your post of the 2nd of February, I had assumed, perhaps incorrectly, that you had employed the use of a metal anvil to re-tension a saw. Are there occasions when a wooden anvil is to be preferred to a metal anvil for the purposes of re-tensioning a saw?

The steel anvil does the real work....the wood anvil (they were often end grain lignum vitae) merely cleaned up any dents caused by mis-hits after the blade was tensioned on the steel anvil.

The old saw factories used large trip hammers for tensioning. I recommend you start with a light ballpeen hammer, and work your way to a heavier hammer as you get the hang of striking with enough accuracy to avoid dents.

A problem spot near the tip of the blade is often a previously repaired kink, and they are difficult to fix. I take out kinks by hammering them out fromt he teeth upwards to the back, which also untensions the blade. Then after the kink is ironed out the balde has to be retensioned.

Here's what I've posted elsewhere:

Truing and tensioning a circular saw blade is difficult, and doing it by hand was artful. These days it's done by a machine that spins the blade, measures the runout with an integral dial indicator and hits them with a hammer/anvil integral to the machine. You can see the marks when they come back from the sharpeners. A blade even slightly out of true gets worse fast at 3000 ft/min blade speed.

Hand saws, however, are easier, aren't as critical, and there's no reason you can't fix yours at home. If the saw ever kinked during a cut, it probably needs retensioning, and those mysterious small dents in old saws are often from mi####s at the sharpening shop.

Striking the blade on an anvil causes a dimple that pulls the steel toward it a tad. The further you get from the dimple, the greater the tension caused, and the closer, the least. Dimples on one side without identical dimples on the other will cause the saw to pull to one side.



So the trick is uniformity. Mark both sides of the saw identically near the center of the blade, and alternate sides as you strike. For thin hand saws, a 6oz ball peen hammer is ideal. I used three raps per mark on this #12 blade, and I also rapped between my chalk marks. Some hammer in successive lines all the way from back to edge for max edge tension at the expense of back stiffness, but as I use saws often in awkward positions, I prefer more uniform stiffness with less danger of kinking.

If the edge is badly bent, then hammer a line close to the edge to remove all tension prior to straightening it....then work your way upwards after you hammer the kink out. You'll be much less likely to snap off a tooth that way.

Flex the saw prior to hammering to get a feel for how loose it is...hammer it as I describe...then flex it again and you should feel a difference. Be careful to keep the hammer face flat as you hit and you won't dent the saw.