How to tell if my saw needs sharpened?

[Frederick Skelly]

Hi guys. I have an LN tapered dovetail saw. It's a great tool. I have cut (literally) about 120 pairs of dovetails with it. I am now having a difficult time starting my cuts and they just seem to take more effort. I'm wondering if these are signs of a saw that needs sharpened? (I've never used a saw enough to need sharpening, so I'm ignorant on how to tell.) When I run my finger over the teeth, they still feel sharp.

I thought it might be my technique causing the problem. But when I switched to another saw, the cuts went just fine.

Please teach me here.

Thank you.
Fred

[William Fretwell]

120 dovetails would depend on the wood being cut more than anything. A quick draw of the file on alternating teeth, each side, won’t take long and you will have your answer! Sharpening does not have to be a big rigmarole, can be very simple and quick.

[Michael Bulatowicz]

Fred,

I’m far from an expert on saw sharpening—surely some of them will weigh in here. That said, it’s my understanding that the outside corners of the teeth dull first; the teeth might still feel sharp to your fingers even if they’re dull at the outside corners. If it’s not cutting well, chances are it has needed sharpening for a while.

I would recommend that you go ahead and sharpen it yourself, even if you’re not presently comfortable doing so. Pete Taran’s website (www.vintagesaws.com) has an excellent tutorial (the saw sharpening primer). I had a bit of trepidation the first time I sharpened my dovetail saw (it had noticeably slowed down in cutting by that point), but now I feel comfortable doing so and I enjoy the continued improvement in my skills.

[Scott Winners]

I agree with Michael, saw sharpening is worth learning how to do.

I haven't fooled with backsaws yet, so I don't have specific advice on that. I will need a light with a magnifying lens in it to take those on.

Definitely start with Pete Taran's website as above. I also found Leonard Lee's _Complete Guide to Sharpening_ helpful. For regular saws, 18-30 inches, I cut a 30 inch slit in a 40 inch 2x2 and use the face vise on my bench as my saw vise.

Even if it is a very simple grind, a rip saw with very small teeth, you will want to file every other tooth from one side, and then do all the teeth you skipped from the other side so you have an even amount of burr on each side. You got to be able to see what you are doing every step of the way.

If it is filed rip you might could build your own saw file holder and skip the LV/Veritas saw file holder. If it is filed crosscut I find the Veritas saw file guide to be worth it's weight in gold.

Set is the other problem. I have no idea how to set teeth on a saw that small, but if you keep banging out dovetails someday you may have to figure it out.

120 dovetails would be 480 cuts, right? It might be your saw will benefit from a thorough cleaning, but 480 cuts at a half inch each, 240 inches, you might have ripped a twenty foot board with that thing, it probably will still need to be sharpened after you clean it.

Good luck, best wishes. In previous threads I have searched up here some folks have had two dovetail saws so they could keep working while one saw was getting handled by a pro, and this is a path I may choose myself given my eyesight.

If you decide to take it on, I encourage you to start on something cheap with less than 10 teeth per inch. A total rust bucket that already has a bottle opener bolted to the plate at the antique store. Just get a triangular file from Lowes-Depot, watch a couple you tubes and figure out if you have any appitude for this at all before you risk your nice dovetail saw.

[Jim Koepke]

Another endorsement of Pete's site at Vintage saws.

My recollection is there is also something about holding the saw points against the palm of your hand to get a feel for sharpness.

Take a look at the teeth with a magnifying glass. You will be able to see a sharp edge versus a rounded edge. Look closely at the outside corners of each tooth.

You might also try dragging the teeth through a hunk of wax to see if that makes the saw work quicker.

jtk

[Frederick Skelly]

Many thanks guys. This helps!
The dovelails were cut in pine and poplar. I hadn't seen Pete Taran's site before. I will read that article. I'll also get out my loupe and examine those teeth after work tonite.

Best regards and Happy Holidsys,
Fred

[Jim Matthews]

A shortcut to tuning a saw (as opposed to filing teeth) is to use a diamond file or popsicle stick with Wet/Dry sandpaper affixed to bevel the bottom of each tooth, near the pointed tip.

That buys a little time.

https://youtu.be/yfefD6NARiY

PS - I file my fine tooth saws (like a dovetail saw) riptooth pattern, and there's little to remember.

[Ben Ellenberger]

I’ve only sharpened my saws a handful of times, but the first time I did it made a huge difference and I realized I should have done it much sooner. Sharpening a rip saw isn’t difficult. Watch a video or two then go to town. Lie-Nielsen has a good video and Paul Sellers does to. A piece of wood with a slot ripped in it works fine for a saw vise.

if you have a rip saw with bigger teeth, it might make sense to practice in that first before sharpening your dovetail saw. The files are cheap so get ones that are the right size for each of your saws.

[Tom M King]

If you think it might, it does. The hardest thing to overcome in learning how to sharpen one is reluctance.

[Frederick Skelly]

Jim, Ben, Tom - thank you!

[Stew Denton]

Fred,

To add to what is written above, one way that I have looked at saws to see if they are dull is to take them out into good sunlight or inside under a good light. I then hold the saw so the light is coming over my shoulder, and look straight down the tooth line. This done while pointing the toe of the saw toward me and the heel of the saw pointing away from me. I then carefully look at the points of the teeth. There should be very little light reflected back toward my eye if the saw is very sharp, because the points are very sharp and not flattened. I have only tried this approach a little, but have been very encouraged by it. I plan to do that technique any time I sharpen a saw now that I have stumbled on to it.

On the other hand if the saw is dull you will see a lot more reflected light. Doing this helps you see the points better. I have done this primarily when sharpening a saw, because seeing the points well is hard for me. I am to the place that I want to get a magnifier that slips on the head with a band around the head and a bill that holds the magnifiers. The magnifiers can be lifted up out of the way or flipped down to help see with some magnification. I have a cheap set, but plan to get a good set eventually. I tried a good set with glass lenses one time, and it is much better than the one I have that has plastic lenses. You get what you pay for.

You can also use a small hand held eye loupe to see small objects. I have had mine many years, and I don't remember when I bought it, but it may have been 40 years ago or more, but I don't remember with any certainty as to the date or cost. Mine is all metal, chromed or polished stainless steel, and has two small swing out lenses, one 10X and the other one 15X. I primarily use the 10X because it is much easier to use, that is partly because the 15X is a very small diameter. I saw on the auction site that some have higher power but with the larger diameter lens, these may be easier to use than the small diameter 15X I have. The actual 10X lens portion itself in mine is slightly less than 1/2" in diameter and the 15X is about 1/4" or a bit less in diameter.

I looked on that auction site, and inexpensive single lens loupes can be bought for around $5 or more. Japanese made ones go for quite a bit more. Mine is a name brand one from Japan, and am thinking I may have bought it 30 or maybe even 40 years ago, and paid about $10, quite a bit for me back then. However, again I don't remember for certain, but that is my recollection. Bausch and Lomb loupes typically go for still more than the Japanese versions. If you buy a used one make sure that the lenses are not scratched up.

Finally, however, I have used hand saws for carpentry for so many years that I can tell right away, when using it, if the saw needs sharpening. What I have a lot of trouble with, again, is seeing whether I have gotten all the points sharp when I am doing the sharpening, which is when I go to the good light and look down the tooth line.

Regards,

Stew

[Frederick Skelly]

Fred,

To add to what is written above, one way that I have looked at saws to see if they are dull is to take them out into good sunlight or inside under a good light. I then hold the saw so the light is coming over my shoulder, and look straight down the tooth line. This done while pointing the toe of the saw toward me and the heel of the saw pointing away from me. I then carefully look at the points of the teeth. There should be very little light reflected back toward my eye if the saw is very sharp, because the points are very sharp and not flattened. On the other hand if the saw is dull you will see a lot more reflected light. Doing this helps you see the points better.

You can also use a small hand held eye loupe to see small objects. I have had mine many years, and I don't remember when I bought it, but it may have been 40 years ago or more, but I don't remember with any certainty as to the date or cost. Mine is all metal, chromed or polished stainless steel, and has two small swing out lenses, one 10X and the other one 15X. I primarily use the 10X because it is much easier to use, that is partly because the 15X is a very small diameter. I saw on the auction site that some have higher power but with the larger diameter lens, these may be easier to use than the small diameter 15X I have. The actual 10X lens itself in mine is slightly less than 1/2" in diameter and the 15X is about 1/4" or a bit less in diameter.

I looked on that auction site, and inexpensive ones can be bought for around $5 or more. Japanese made ones go for quite a bit more. Mine is a name brand one from Japan, and am thinking I may have bought it 30 or maybe even 40 years ago, and paid about $10, quite a bit for me back then. However, again I don't remember for certain, but that is my recollection. Bausch and Lomb loupes go for still more. If you buy a used one make sure that the lenses are not scratched up.

Regards,

Stew

Thanks Stew! I looked at it earlier today with a cheap loupe I have, and I saw lots of shiny points. I was trying to find out what that meant and you answered it!

All: I spent some time today looking at Paul Sellars saw sharpening vids that Jim Matthews suggested above. With all your encouragement, I'm thinking I may try to do this on an old rusty backsaw and see what happens.

I appreciate everyone's help here,
Fred

[Stew Denton]

Fred,

If you are going to have a go at your dovetail saw eventually I would encourage you to buy good files. We have had that exact discussion many times here. Many of the old time brands are not nearly as good as they used to be. Last time it was discussed, some of the folks said that Nicholson files are starting to get a bit better again. They went bad after having them made in Mexico and other non-USA sites. For a while they had gotten pretty sorry, being way too soft. Some folks had said that one brand of files made in Portugal, this since 1865 or so, were still high quality saw files, but are not widely distributed in this country.

One of the saw smiths on our site had mentioned that they were going to start handling that brand on their web site, so we could purchase some from them. I don't know whether they did or not. I bought mine from the auction site a few years ago. I also have a number of quite vintage USA made Nicholsons that I use on my carpentry saws, these purchased new many years ago and well taken care of, and the vintage Nicholsons are quite good. I am in fair shape on those that are carpentry saw size. I have not attempted to sharpen one of my dovetail saws yet, but that is coming as they need it.

You need very small files for your dovetail saws, and I don't recall for sure, but I think that you are looking at a 4" extra slim or double extra slim for something like a 15 point dovetail saw. When I get around to it, I do have some of those from Portugal.

There are some from Portugal on the auction site, but they are pretty pricy, and the ones I bought there were a lot less expensive, but that was a few years ago. If you type in "saw files Portugal" an assortment comes up that you can look at. Again pretty pricy though.

I also added more information to the post you copied into your note above.

Stew

[Frederick Skelly]

Thanks Stew!

[Stew Denton]

Fred,

I just looked on the auction site, and there are a lot of vintage Nicholson files there. I didn't look to see if they had any the right size for dovetail saws, but you might look. Make sure they are still good and not used rust buckets though. NOS is ideal if you find the right sizes. Several of the good old time makers, back when they still made good files, show up there also. If the seller knows what he has the prices will not be cheap, but often the seller does not know files from pineapples, and those can price the files reasonably.

Stew

[Michael Bulatowicz]

Isaac Smith of Blackburn Tools likes Bahco (made in Portugal, if I remember correctly) for most files, but prefers Glardon three square needle files for 11-20 ppi (http://www.blackburntools.com/blog/concerning-saw-files-which-i-am-now-selling/). He sells them, but is backlogged with orders at the moment. Lee Valley sells the Bahco files as well (https://www.leevalley.com/en-us/shop/tools/hand-tools/files-and-rasps/files/69854-bahco-saw-sharpening-files). I have used the 5 inch XX slim Bahco for a half dozen or so sharpenings so far and it’s still going strong—no sign that it’s going to wear out any time soon.

[Mike Henderson]

If you don't want to sharpen the saw yourself, Lie Nielsen will do it for $25. You pay postage to them and they pay postage back.

The problem for me is that I don't need to sharpen a saw very often so I haven't put the effort into getting the tools and learning how to do it. For my LN saws, I'll just return them to LN for sharpening. They do a great job.

Mike

[Stew Denton]

Mike,

Bahco were originally made in Sweden, but my understanding also is that they are now made in Portugal as you mention. That being the case, I suspect that they are made for Bahco by Tome Feteira who is the maker I was talking about above. Folks here mentioned on some of the discussions about saw files that Bahco was not making files as good as they used to, but that was a while back. If Tome now makes them for Bahco, then the chances are that they are now pretty good files.

Stew

Stew

[Tom M King]

I set a light so that a freshly sharpened tooth shines back at me. That saves a split second of deciding which is the next tooth. Differently than maybe anyone else, I use one hand on the file, whether sharpening a hand saw, or a chainsaw chain. The whole file gets used, and pressure of each stroke is decided in the split second when the little smooth end of the file finds the next gullet. Having two hands on the file really slows me up, and blocks the view I want, as well as the light. When filing outside, there is no light needed, and chainsaws are mostly sharpened while sitting on the tailgate of the truck.

I buy full length files, so use the whole length of the file.

Never back up with a file.

Find a file handle that works for you. The Oregon chainsaw file handles fit my hands perfectly, so I buy them by the dozen for less than a buck a piece, and they can be reused. Buying them by the dozen allows me to keep a handle on each of the different sizes of files.

My guide is only a wooden strip laid behind the vise with the angles drawn on it. The other side has the angles going the other way. Any holding of the file in even a slightly different angle than those drawn on the "guide" is hard to miss.

When first learning, position a piece of white paper right behind the tooth line, and see how much metal is thrown on it by different types of file strokes. I did this when I taught Boy Scouts how to sharpen a hatchet, and it always helped. You can see that long, smooth, light strokes can remove as much metal as short, hard strokes, and the cutting edge will be finer as well.

Hard strokes are fine when needed, but light strokes are a lot less work. Fewer strokes are noticeably less work than more strokes, so sharpening often ends up being easiest in the end. When only one light stroke is needed, you can go right on down the line really quickly.