carcass saw drifting to the left

[Bob Glenn]

I have a gently used L/N carcass saw that drifts to the left. It will pull about 1/64th of an inch in a two inch cut. I only noticed it while cutting the cheek of a dove tail. I don't think it is my technique, since I don't have the problem with other saws. Should I ask L/N to fix it, or run a stone down the left side of the teeth?

[Pete Taran]

Bob,

You could try that, you could also apply more set to the other side and see if that corrects the problem. When the blades are made, there is a burr on the left side because that is the side that goes against the revolving punch. Even after filing, you need to compensate by applying less set to the blade side and more to the right so it's even on both sides. There are lots of ways to fix the problem to include lightly tapping the over set side. Stoning was always my last option as it affects the geometry of the edge of the tooth.

Pete

[Derek Cohen]

I agree with Pete. Stoning is the last strategy to use since it removes metal.

One other method is to equalise the set. Use the trick that Mike Wenzloff published: wrap a sheet of copy paper around the plate/over the teeth (or use a strip of blue tape). Then squeeze the teeth together inside a metal machinist's vise. The paper will prevent the set being flattened, but will even it up over the two sides. I have done this successfully on several occasions.

Regards from Perth

Derek

[Pat Barry]

The thing about the squeezing together method described by Derek is that the steel may not get bent enough to actually effect a significant change in the set. This is because the steel will tend to spring back to its original position when the force is removed. You need to bend enough to 'plastically deform' the steel. Of course, try it, it can't hurt - but keep in mind it doesn't solve the problem for all conditions. In the case described, the set of the offending side will possibly be reduced enough to improve the situation though.

[lowell holmes]

I have fixed this issue by gently stoning the teeth on the side the offset is to.

Only stone 3 or 4 strokes at a time. Don't get carried away.

That way you can see how much you have done before you go too far.

I never worried too much about it, because I can always reset teeth (and have I might add).

[Ron Bontz]

Just my nickle. Stoning should always be the last resort. IMHO it does nothing more than dull the teeth on that side. Cross cut saws in particular. ( No doubt what Pete was referring to. ) The before mentioned burr caused by the punch should be removed before the teeth are shaped, set and sharpened. Otherwise it can and may very well affect the setting process. I can not speak for the Lie Nielsen saw process, other than they are engineered well, but I do know some folks seem to think the burr is always removed through sharpening. Not necessarily. You may also just have a couple of rouge teeth out a little further, in which case the machinist vise may be of benefit, but will alter the geometry as well. Lastly, you may wish to place the saw plate back on a nice flat surface. Jointer, etc. ( I use a surface plate ) holding the back flat on the surface, and compare the gap between the teeth and jointer surface when you flip the plate over. The gap between the teeth and surface should be the same on both sides. If not the plate and back slot are not co-planer. Hopefully I said that correctly, but either way, not likely the problem unless the spine slots are being compressed. That's another story. :):) Best wishes, Ron

[lowell holmes]

I don't disagree with Ron. In my case I had re-toothed two saws and was not worried about flattening the teeth. . The burrs on my saws was caused by filing, not punching. I file the teeth in my reworked saws. I don't have the capability of punching teeth. I maintain spacing with paper templates taped to the side of the saw plate. I've only told a bit of the process. The set was put in with saw sets and was not uniform as a machine might do. The set looked uniform, a couple of the teeth were out and I had the choice of squeezing with pliers or filing.

Obviously you do not want to change the geometry of the teeth.
Ron is the professional and I am an old duffer.:)

That being said, I have sent two older saws to Lie Nielsen and they returned to me perfectly sharpened and set.

[Patrick Chase]

I don't disagree with Ron. In my case I had re-toothed two saws and was not worried about flattening the teeth. . The burrs on my saws was caused by filing, not punching

Wait, let me guess: You're following Ron Herman's advice and only filing from one side?

If you took your final (sharpening) filing passes from both sides then you wouldn't need to fix that :-).

[Stewie Simpson]

Patrick; your not suggesting you know more about sharpening a hand saw than Ron Herman.

Stewie ;

[Stewie Simpson]

As Ron rightly points out, the teeth that are machined punched will produce a pronounced burr on the underside. I

[Patrick Chase]

Patrick; your not suggesting you know more about sharpening a hand saw than Ron Herman.

Stewie ;

Nah, I was mostly lightly ribbing Lowell because he suggests that people watch the Herman video whenever saw sharpening comes up, hence the ":-)".

I'm well aware that the "file from one/both sides" thing is an Eternal Flame, about which experts disagree and get better results than I ever could both ways. I personally do final sharpening from both sides (shaping is another matter) because I prefer to avoid any inherently asymmetric steps in my process, but that's just me.

[Stewie Simpson]

As Ron rightly points out, the teeth that are machined punched will produce a pronounced burr on the underside. There's a fair chance LN would be using this process with their hand saws. That's not to suggest that the burr formed cannot be removed during later fine tuning if their quality control is set up accordingly.

[Pete Taran]

I'm sure they are using the same equipment and methods I used when I sold them Independence Tool back in 1998. As Stewie and others pointed out, the burr needs to be stoned away before filing. I think there is more here than meets the eye though, burr or not, the steel is stressed from being punched, and it is MUCH easier to set it on one side than the other. I used to compensate for this by increasing the set on the non-stressed side and decreasing the set on the stressed side. By stressed side, I mean the side that is facing the anvil of the punch. The effect can be very dramatic if you don't approach it carefully.

This is assuming you like as little set as possible. If you set quite a bit, it doesn't make much difference. I always worked to have a total tooth width of .023" for a .020" plate. That's not a lot of room to maneuver, and the set has to be perfect for it to cut right.

Hope this helps. BTW, I filed the several 1000 dovetails saws I made back in the day from the same side.

Pete

[lowell holmes]

Too much work swapping sides.:)

I do shape the teeth by filing from one side only. If burrs occur, they are removed before sharpening.

Actually, I learned to sharpen by watching Ron Herman's video. My saws are performing really well.

[Stewie Simpson]

Pete; how did you overcome curvature of the saw plate after it was fed through the toothing machine.

regards Stewie;

[Pete Taran]

It really didn't curve that much, not like a full width handsaw. Plus, it was set in a milled back so it was kept pretty straight. In my experience, most of any curve is removed after the saw is filed and set.

Cutting the strip is another matter however. You would get a pretty good curl when using a shear. I would cut it long and then flip it around and cut it from the other direction to even it out.

Tips of the trade. My only lament is that I could not watch the Ron Herman video on how to file saws back in the day when I got started. :p

[Stewie Simpson]

Its well worth mentioning that the odd tooth with slightly more set will have a slightly lower top line profile. A condition that's not hard to replicate with most hand held saw sets. For that reason, my personal preference is to give the tops of the teeth a light single pass with the jointing file after setting. After that, a light pass to each tooth with your taper or 3 square file will return them back to a sharp point. Advise to consider.

Stewie;

[Stewie Simpson]

Pete; most of the saw plate I use for making backsaws is still coiled. After shearing to length, the next thing I do is lightly joint all 4 sides side with a flat file. 9/10 cases it removes the stored memory of being coiled. The odd case is generally rectified after being toothed and fitted to its hardback. I shape all my saw teeth by file, and by deepening each of the tooth gullets in progressive passes, the saw plates flatness is not compromised. That's should not suggest I am trying to undermine the use of a Foley Machine.

Stewie;

[Pete Taran]

Stewie,

Whatever works for you is fine by me. I am alway curious about why people don't want to use more automated methods though. Back in the day when Disston made more saws than anyone on the planet, they punched their saw teeth, one at a time with a hand operated punch.

I used a rotating foley and once you understand the limitations and how to overcome them, it works great. I've done limited production runs since, and the ultimate is to cut them in stacks of 10 using a carbide dovetail cutter in a fixture on a mill. No tooth is more precise or sharp than one from a milling cutter spinning at 3000 rpm. :)

[Stewie Simpson]

Pete; as I mentioned I have nothing against those that use a Foley Machine. I was merely pointing out that I take a different approach to shaping the saw teeth. Possibly more in line with those that aren't concerned about saving time.

Stewie;

[steven c newman]

This old rip saw..
346015
was sharpened up a while back. It used to drift to the right.....badly. Stoned the teeth about 4 times, going from heel to toe..
346016
Not sure IF you can see the cut line, vs the sawn line. It now drifts ever so slightly to the left. Will have to go back and a pass down the left side.

Unless this is more of an "Operator Error" sort of thing....

Saw is a Keystone "Challenger" K-6-1/2. 5.5ppi, 26" long. I filed it rip this past summer.

[george wilson]

We used a little "Burro" tooth punching machine,which I wish I still had. But,what the heck. I am not going to get back into making saws anyway,especially now that it apparently is impossible to buy USA made spring steel. If I was,I'd have to go with Austrian steel. I do have a small supply of USA spring steel should I ever want to make another saw or two. I DID buy a Foley from a member here,but have no space to set it up. At least,not unless I started actually USING it!:) We kept the cutter and the die from the little Burro quite sharp,so it left a minimum of burr to the teeth,and a minimum of affecting any curve. That as really a GREAT little machine. Very compact and could be lifted down and stored between uses. The Foley is a lot larger to do the same job.

I prefer punching the teeth,too,especially with the trouble of getting suitable files,which I'd not want to wear out un necessarily by filing whole teeth out. On 1095 at 52 RC. hardness,it was hard enough on good USA made Nicholsons anyway.

I guess it's too late,Stewie,manufacturing spring steel being what it is these days,but we took to buying PRE STRAIGHTENED spring steel after going through the first coiled up .042" steel for crosscut and rip saws. We just bought it longer than we'd need by a few inches(to be safe). Now,I don't know WHAT you could get.

As I have mentioned here,we discovered that bending the curved plate and pouring boiling water over it would very effectively eliminate the curve,and no harm at all to the temper(which was done at 750º F..) I'd rather do that,and eliminate the curve from the whole plate,rather than trying to eliminate it by doing stuff to the teeth,which process will be changed by subsequent refiling. Then what? Can the plate go back to being curved? Just get rid of the WHOLE plate's curve to begin with.

[Stewie Simpson]

George; read my post again.


Pete; most of the saw plate I use for making backsaws is still coiled. After shearing to length, the next thing I do is lightly joint all 4 sides side with a flat file. 9/10 cases it removes the stored memory of being coiled. The odd case is generally rectified after being toothed and fitted to its hardback. I shape all my saw teeth by file, and by deepening each of the tooth gullets in progressive passes, the saw plates flatness is not compromised. That's should not suggest I am trying to undermine the use of a Foley Machine.

Stewie;

[steven c newman]

Is this the machine? I didn't have the room for it, otherwise I might have made an offer for it...
346035
There was a grinder of sorts, sitting the the left of it, as well..
346036
Not sure IF these two were part of a set.

[Patrick Chase]

Pete; most of the saw plate I use for making backsaws is still coiled. After shearing to length, the next thing I do is lightly joint all 4 sides side with a flat file. 9/10 cases it removes the stored memory of being coiled.

The "memory" in this case is just strain, meaning that some of the steel has been stressed beyond its yield strength and has bent. Stress in a bent sheet is higher at the surfaces than at the center (for simple bending of a thin sheet it's actually zero at the center), so any strain/bending would occur at the surfaces.

It therefore makes sense that jointing the surfaces would eliminate "memory", as you're removing exactly the part of the metal that's most likely to have been bent.

[Ron Bontz]

Just an FYI. A properly sharpened and aligned ( punch and die ) will have a minimal burr. Filing does not create much of a burr at all. After about 200 to 300 saws I believe I can safely say it doesn't matter if you file from both sides or just one side. In either case, a very light final pass seems to remove any remnants of fine burrs.
That being said, if the steel is softer than usual, ( ie: less than 48 to 51RC ) and there is a slight gap between the punch and die, you will no doubt see a more significant burr on the die side of the punched teeth. { Bet you couldn't guess how I know that. } :) The steel basically stretches before it shears. ( Deformation of solids )
In any case, I have no doubt the company would take care of the saw if it becomes an issue. They have some pretty good customer service.

[Stewie Simpson]

Thanks Ron; appreciate your feedback.

regards Stewie;

[lowell holmes]

I built a 20" back saw from a Bontz kit. It turned out great, has no vices. His formed back with the blade set in epoxy is really good.

I wanted a tenon saw on steroids and I got it.

[george wilson]

If I WERE to ever make a slotted saw back,which is not likely,I think I'd prefer to set the blade in a good grade of Loctite rather than epoxy. Epoxy can crack loose on a smooth surface like a saw blade. Loctite holds like crazy. They even use it on nuts and bolts on Indianapolis race cars instead of the old safety wires going through holes in the bolts and into castellated nuts. Those cars must survive incredible vibration at the speeds they run.Must really have been terrible trying to drive fast on a BRICK road,which was the track there many years ago,before it was paved over. They called the track "The brickyard".

[lowell holmes]

George,
I mis-spoke. I did bed mine in Loctite.

Since my daughter-in-law is in marketing for Henkel, I use Loctite.:)

[Ron Bontz]

Hi Lowell. Thanks for the stealth plug. Intentional or not :)
As far as glue is concerned, I occasionally use a few drops of loctite, but I mostly just compress the spine slot. Glue does not make a joint. It simply strengthens it. I actually made a hydraulic jig a couple of years ago, maybe three years ago now, I forget, just for the purpose of compressing the entire spine at once. If done well the spine is as rigid and tight as any folded brass back. I actually ruined a saw plate the other day, because I couldn't get the plate out of the spine to correct a small misalignment. Opps! Should have left it alone. (&&(#(#&(&#*) Yep, I shall not type what I said. Plus you have a solid 3/8" of back you can shape, etc. I know, I know. Shame on me for sculpting the spine. :) I do have to be careful to "tension" the plate into the back, but a slotted back, unlike a folded back, has a repeatable reference point for the plate to seat against. Enough said about that.
Having mentioned folded backs, I will not say one type of back is superior to another as that is just an opinion and/ or marketing ploy in my view and, of course, always stirs up controversy. But rather say every type of saw back made has it's pros and cons. Including folded, slotted, laminated, and moulded. I have made steel folded backs in 10 gauge as well as 11 and 12 gauge and bought a few as well. I even have a couple of hydraulic presses sitting in my shop, strictly for that purpose. So maybe I will offer them some day. ( Some day ) Then again I have been telling myself, for several years, I am going to make myself a nice set of matching joinery saws out of Madron Burl with all the bells and whistles. Basically functional presentation saws complete with engraving. Hmmm. Well, Ok, so maybe that's someday too. :):) Now back to work. Lunch is over. Best wishes. P.S. We are way off track now.

[Patrick Chase]

George,
I mis-spoke. I did bed mine in Loctite.

Since my daughter-in-law is in marketing for Henkel, I use Loctite.:)

Henkel bought Hysol a while back so they make great epoxies, too.

The slow-cure Hysols are right up with the best of them (West G-Tech, etc) and superior to any single-component adhesive for tough materials including smooth steel. Of course it helps to have a hot box, as the really strong-gripping, tough epoxies don't fully cure at room temp. IIRC Hysol 9460 only cures to 50% strength at 70F, for example.

Looking at spec sheets, Hysol 9460 scores ~3200 psi for lap shear on degreased (but not sanded/blasted) 1018. The corresponding number for Loctite 262 (the permanent kind, let's not even talk about removable threadlocker) is ~2000 psi.

Even room-temperature-cure Hysol 907 scores about 3000 psi for lap shear on steel, but it isn't as tough, gap-filling, or temperature-resistant as 9460. The catch is that it takes 3 hours to set and 24 hrs to cure at room temp, but for critical applications it's worth it (and if you have a hot box you can get the cure time down to a couple hrs).