Hand Saw Straightness Tolerance

[graween]

Hi all.

I received a new saw yesterday. And as I checked the straightness of the saw tooth line, by eye only for the moment (it was late), it seems that the last 2 inches at the toe are not straight.
I'll mesure it tonight. But I would say it forms a bow on on side about 1 or 1.5 mm at the end.
The saw is a pax 26".
I'm not sure before really checking that is it in the tooth line (my actual guess) or on the whole depth of the blade.

My questions are before I check more thoroughly tonight.
- Would that affect the saw usage, as mostly except for starting the cut, this part is not used that much.
- Is it within the regular tolerance for saw blades, as they are so thin and wobble easily (if hold in the air), without affecting the cut durgin strokes.
- How straight are your saws without affecting the usage.
- For a brand new saw, never used should I return it to get an other one, or will it be the same ?

Best Rergards,
Graween.

 

[carpenteire2009]

Hi
I recently purchased a new Pax saw myself; they do feature a breasted toothline- the toothline is slightly convex, a desirable feature in a quality saw. Maybe I've misinterpreted your post, but I don't think you've anything to worry about there.

 

[graween]

Hello carpenteire2009,

I know the tooth line is breasted.

I'm talking of a bow in the plate. In other words the tool line deviates on the left at the toe (front of the saw).
the curve starts at about 2 inches / 5 cms of the toe.
To be more clear, if you look at the saw holding it by the handle with the tooth line up, and watch the line, at the end of the plate at the toe the tooth line curves to the right (updside down in this case).

Hope this clarifies the problem, if this is a real problem anyway.

Thanks.

 

[Racers]

Hi, graween

It should be straight, so send it back.


Pete

 

[Derek Cohen (Perth Oz)]

Hi Graween

It is likely that the kerf in the handle (above the curve in the blade) is not straight. This is the reason for the curve in the blade at this point.

Try sawing with it. If the curve is very slight it probably will not make a difference. If the curve is more than this, or the sawcut is compromised (skew or rough kerf), then return the saw. You could re-cut the kerf after first plugging it with veneer, but that is not your responsibility.

Regards from Perth

Derek

 

[pedder]

It is likely that the kerf in the handle (above the curve in the blade) is not straight. This is the reason for the curve in the blade at this point.

If I got Garween correct, the bow is at the toe:

To be more clear, if you look at the saw holding it by the handle with the tooth line up, and watch the line, at the end of the plate at the toe the tooth line curves to the right (updside down in this case).

In this case it does not seem to be a matter of the handle.
You can bow it to the correct shape but I would ask the seller in first line, if that is OK.

Cheers
Pedder

 

[barkwindjammer]

Sorry for the thread hijack, if a saw plate has a bow/kink in it, and you wanted to hammer it out, which side of the plate would you plannish ?

 

[matthewwh]

BWJ - the convex side, but in this instance I'd give the retailer a call first (or Katie if you bought it direct).

Saw plates should be straight and in all fairness this is the first instance of a Pax being anything but straight that I have ever heard of. It may be postal damage, all of these saws are handmade so the guys work with them intimately, I can't for a moment imagine Christian carefully sharpening a bent saw and then putting it into a box.

 

[xy mosian]

Sorry for the thread hijack, if a saw plate has a bow/kink in it, and you wanted to hammer it out, which side of the plate would you plannish ?

I only once had to do this once, pre interweb days, and looked the process up in a 'Book' in a 'Library'. The advice given was to plannish the inside of the bend. The reasoning went like this. The surface of the metal on the outside of the curve is stretched, much more likely than the inside being compressed. When plannishing the action of the hammer blows is to stretch the metal. Therefore plannish the inside of the curve to stretch the metal to match the outside. Thinking about it, when trying to straighten manually we would naturally attempt a reverse bend, thereby stretching the metal on the inside of the curve.
Any road up. My attempts were suprisingly effective and I manged to rescue a scrap handsaw.

Hope this helps.
xy

 

[Jacob]

If you use it a lot it'll end up a bit bendy anyway. Maybe just ignore it, or just give it a little twist to see if you can straighten it. Or a big twist - bend the blade smoothly round in a semi circle one way and then the other. This sometimes pulls out little irregularities.
I certainly wouldn't start hammering it it could end up much worse if you don't know what you are doing.

 

[matthewwh]

If you are using a proper planishing anvil (small contact area) and planishing hammer (big contact area) then hammering the inside of the curve makes sense. If you are resting it on a bit of softwood and giving it a few judicious taps with a ball pein the contact area situation (and therefore effect) is reversed.

Either way, it's a new saw with a fantastic manufacturer's lifetime warranty etched into the blade, so the best tool for the job is a telephone, not a hammer.

 

[Racers]

Hi, Chaps

I copied this from the oldtools list some time ago, I didn't save the name of the orignal poster.

Hello all sawing Galoots !

A while back - so long ago that it fell off Galoot space into the ether
- I posted a question about straightening bent & kinky saw blades. I got several responses. Two notable ones that made me see the light came from Todd Hughes & Chris Swingley (whose archive website no longer attacks my ports ... according to McAfee; thanks, Chris) which describe the essence of the straightening process:

Hold the saw so it is forced straight while you have the end(s) above the flat on the anvil. Then tap it with the (slightly rounded) flat end of a ball pein (peen) hammer - never with the round end. The idea is to squish the metal, not to bend it.

I paraphrased their descriptions of how the blade must be held against the anvil in order to try to come up with a description that I can visualize.

What's the mechanism ? Well, here's the geeky part. It helps me think through the process so too many saw blades don't become scraper blades, 'cuz I figgered out a while back how to make a lifetime supply from old hacksaw blades.

Imagine a long wire with a weight hanging on the end. Now turn the weight around a little bit and let go. The weight spins the other way, back & forth for a while. The wire has stored some elastic energy and is sending it back to the weight by unwinding. Now imagine winding the wire up a little bit and then yanking on the wire so that it stretches permanently no more than half a percent. When you let go, the weight doesn't spin. That's called the Ho'enemser experiment - 'scuse the spelling, it's been a long time since that lecture. It's used to describe an important theorem in the theory of the plasticity of metals:
The Normality Flow Rule. Also called the Associated Flow Rule. It says
(really) that the plastic strain vector is always perpendicular to the surface of the yield locus. Another less mathematical way of stating this rule is that if you are stretching a wire (for example) so it is permanently elangating, even a little bit, that any elastic strains (and
stresses) in the wire that were present before the stretching started will be erased forever. It's used to keep a bent piece of metal from straightening out (springing back) when the corner of the bend is ironed
- hammered so that it is fully plastic. Beer cans are made by a process called drawing & ironing, so their very thin sides don't get all squiggly. You might have used a similar process to slide a refrigerator across the floor - if you twist it from side to side, it slides much easier than if you just push. When the metal is already yielding in one direction, it doesn't take much to get it to move in another direction by applying a nudge in that direction.

Back to the saws. Hold the blade so it won't hold water. Press it down against the top of the anvil so the bend gets flattened out. Now hammer the top side right where the bend is flattest (i.e., in the middle of the most bent part) so that you're ironing the bend. It won't spring back any more when you let go, 'cuz the bending stresses are all gone.
The trick is to get the whole width of the bent area hammered this way without stretching the metal (as in the making of a dish) and without making half-moon-shaped dings. This ought to be a quiet process if the saw blade is really held down tightly against the anvil. The blows need not be heavy. Todd is absolutely correct when he says that you're not trying to bend the blade. Just flattening it by deforming it through the thickness while it's held flat against the anvil.

Applying this to a blade that's gotten curved the other way - so it's shaped like a measuring tape - I'd say to hold the blade the same way as described above and then hammer all across the part you've forced to flatten out against the anvil, but without making the blade kink the way a tape measure would kink if you bent it too far against the grain. It will bend easily the other way, but it won't lie flat against the anvil no matter what you do.

The Disston Lumberman's Manual gives another hint - placing a couple layers of brown paper underneath a sharply kinked area and then gently pushing the kink down with light blows. It might pop through - then you have to stretch all the surrounding metal to pull the oil-canned part down flat again. The brown paper helps to keep you from stretching the metal by hammering too hard on top of the kink. Sorta like my old advice about straightening bent shafts by holding 'em on top of a length of hard wood so hammering on top of the bend doesn't overbend the shaft.

Pete

 

[graween]

Hi all.

Thank you for the answers. Last night I have checked, so I confirm there is something, not straight.
Now it is very very light. And very difficult to mesure other than eyeballing. Because, the plate is so thin, it moves very easily.
Now the skewed back of the blade is straigth. Only that last 5 cms (2 inches) ov the plate where the teeth are is only slighty curved. Just as if it was lightly cupped starting on a line that would start a 5cms from the toe and end at 1 or 2 cm (1/2 inch) forming a triangle somehow. Not easy to explain for a non native english speaker.
At a moment I was wondering if it was in the setting of teeth.

Anyhow, I'll probably keep it and try to remedy this. I'll contact the seller to see if he's alright that I take a test drive with the saw to see if it works well. And if not return it. AS jacob stated if it's working well, and anyway will end binding one day or the other :?

Matthew.
You seem to know these people and I trust your fairness.
The seller I bougth it from is also very serious.
When the pack arrived it was vvery well packed. But the saw was out ot the cardboard cas it has slipped out of the case at the toe.
But I can't tell when that arrived. Also the external package was very clean, and the seller would never hav put it in the pack like that. I don't think that it's the source of the problem.
Which for me was there before, or some sort of stress relieve ?

I bought it because there were good critics about them.
Taking about the saw though, I don't know how intimately the guys at Pax work on the saw.
3 things in all objectivity about the saw I received.
- It could be more well packed. The cardboard case is of good quality, why not add a little something to hold the saw in it so it does not slip out of it ? Also some folded cardboard to maintain the plate straight ?
- The toe of the plate is not ground perfectly. I mean, where the saw was cut in the original plate, somehow it was grounded there. Don't know it this was on purpose, but never saw that before.
- Don't know if the teeth at the toe where sharpened by hand, ot how they did it. It's a rip saw, and on trailing side of the teeth, they are some burr, that hand sharpening properly done, could not have left.

To be honest, I must edit/complete this point above todayIn fact for this point above, this was in fact some metal dust, probably left after the sharpening, bounded on the teeth, by the varnish or equivalent, they did put on the plate at the factory. Last night I cleaned the tooth and they're fine. So this was because of me.

- And the medallion is set skewed in the handle, something I don't understand how it can be, if the holes are drilled with a pillar drill or equivalent. But it's only aesthetic, not a problem.

So nothing really to worry about, but for a 'top of the line' saw, marketed as good quality, the perceived quality of details is not the best.

Overall don't misunderstand me. The global quality seems fine, and I'll test the saw to see how it performs.
But some details leaves me perplex.

I'll post some pictures of the things I said to make it clearer. And keep you updated.

Best Regards.

 

[thomasflinn]

Hi all.

I received a new saw yesterday. And as I checked the straightness of the saw tooth line, by eye only for the moment (it was late), it seems that the last 2 inches at the toe are not straight.
I'll mesure it tonight. But I would say it forms a bow on on side about 1 or 1.5 mm at the end.
The saw is a pax 26".
I'm not sure before really checking that is it in the tooth line (my actual guess) or on the whole depth of the blade.

Hi Graween - if this is a brand new saw you have purchased either direct from us or via another retailer, then you should send this back to either them or to us for inspection. I would prefer to see if there are any issues in manufacturer that have gone undetected for whatever reason. I would also prefer to see you fully happy with the product you have purchased. If you wish us to look at this saw so that you can be assured that the product you have is going to function to it's highest potential, then please feel free to send this back to us or the retailer you bought this from. It is helpful for us to detect any problems as quickly as possible.
Thanks, Katie - Thomas Flinn & Co. (makers of the PAX saws)

 

[Derek Cohen (Perth Oz)]

Derek Cohen (Perth, Oz) wrote:
It is likely that the kerf in the handle (above the curve in the blade) is not straight. This is the reason for the curve in the blade at this point.

Pedder wrote:
If I got Garween correct, the bow is at the toe:

What do I know ... after all, everything here is upsidedown! :lol:

Regards from Perth

Derek

 

[bugbear]

Saw planishing is covered here:

SAWS: THE HISTORY, DEVELOPMENT, ACTION, CLASSIFICATION AND COMPARISON OF SAWS OF ALL KINDS.

Robert Grimshaw, 1880

Reprint for sale:

http://www.amazon.co.uk/Saws-Developmen ... 327&sr=8-2

Downloadable free here (amongst others)

http://www.evenfallstudios.com/woodwork ... y/saws.pdf

http://www.wkfinetools.com/hUS/z-USRead ... imshaw.asp

Tensioning and straightening with the hammer is discussed starting at p102.

BugBear

 

[graween]

Hi Katie (thomasflinn),

Thank you for your offer. I want to let you know I really appreciate.!

As I mentioned in bold caracters in the previous post, the overall quality of the saw is fine. The ratio quality / price is fine also.
Also as we say in French "evil is in the details", and, I'm sort of meticulous :mrgreen:

I'll send you a PM so we can discuss this issue. First I'll send you the pictures, so you can judge, and give me advices/judgments about the case.
I'm living in France and shipping cost, must be taken in account, before sending back and forth some items like this between UK and FR.

I'll try to take photos tonight.

Thank you very much, the interest for customer satisfaction and sense of service is part of what makes a company stands a step above the others.

Regards,
Erwin

 

[graween]

Hi.
I edited my previous message, to update my comment about the teeth. As it was just a matter of cleaning them quickly.

Thanks.

 

[barkwindjammer]

Cheers guys for the advice and the links that were posted up-much appreciated.

 

[graween]

Hi all,

Just a quick update on the case of my saw. In the interest of sharing my experience.

My issue was adressed by the Pax Flinn Garlick people especially Katie. I must say that they were very nice and professional, in handling this. We exchanged many emails and all was sorted !

I know have a really nice saw 100% perfect. The blade is fine, teeth sharp, and the handle shape is ok with me.
I'm very satisfied with the saw now, and also by the service provided.

Thank you very much Katie.

Regards.