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Noah Wagener
03-31-2015, 8:51 PM
someone told me that having all the different saw files for different size teeth is not necessary because the corners will wear out before the faces so you do not have to worry about having a file just over twice the length of the back of the tooth and the corners on any slim file are small enough to create deep enough gullets. I wanted to hear what you all had to say about that. Do the corners vary that much from a 6 to a 4 inch file? I have a couple files in the 5 to 7 inch range and cannot discern any differences.

I have read how bad the state of saw files has become and even the good ones do not sound like the last very long. What is the reason that no one uses abrasive files? India files are cheaper than Bahco and Grobet and you could shape the corners to your liking. Diamond needle files are not much more than regular saw files either.

Jim Davis
03-31-2015, 9:42 PM
You can use a particular size for more than the recommended PPI numbers, but not a lot different. When you get down to 13 to 15 PPI, that 6" slim taper starts to leave teeth that are more like waves than teeth. I just bought a double extra slim taper 4" that I need for a 16 PPI saw that I made. I was able to sharpen it with a tiny 3-square file, but it isn't right. (The file hasn't arrive yet. Bought it online.)

Jim

Eric Schubert
04-01-2015, 11:05 AM
From my admittedly very-limited experience with saw sharpening, I believe that abrasive files are not typically used to sharpen saws because a traditional file will cut teeth more quickly. For maintaining an already-sharpened saw, I could definitely see using an abrasive file to do touch-ups and whatnot. But cutting teeth from a straight plate would be a long, tedious process without a very coarse and aggressive abrasive. And a coarse abrasive may get clogged with particles as it is used, becoming less effective over time.

Steve Voigt
04-01-2015, 11:30 AM
Noah, you might check out this post by Isaac Smith (http://www.blackburntools.com/blog/concerning-saw-files-which-i-am-now-selling/). If you scroll down to the bottom, there is a simplified chart for file selection. Also, as he mentions, he is now selling the Bahco files. I haven't ordered any but will definitely do so when my Grobets run out.

I've never seen a reference in any book or article to using abrasive files. That suggests it's probably not a great idea.

george wilson
04-01-2015, 12:56 PM
Abrasive files are not the thing to use to try filing a saw with! Solid abrasive files,like India slips will not file rapidly enough to ever get the job done,and will not hold their shape. They are for removing slight amounts of metal like in sharpening a carving tool. Not for actual filing or reshaping of saw teeth. Diamond files will quickly shed their diamonds on a thin piece of spring steel.

Robert Engel
04-01-2015, 1:19 PM
someone told me that having all the different saw files for different size teeth is not necessary because the corners will wear out before the faces so you do not have to worry about having a file just over twice the length of the back of the tooth and the corners on any slim file are small enough to create deep enough gullets. I wanted to hear what you all had to say about that. Do the corners vary that much from a 6 to a 4 inch file? I have a couple files in the 5 to 7 inch range and cannot discern any differences.

I have read how bad the state of saw files has become and even the good ones do not sound like the last very long. What is the reason that no one uses abrasive files? India files are cheaper than Bahco and Grobet and you could shape the corners to your liking. Diamond needle files are not much more than regular saw files either.Jim Davis is correct. Get the right file for the tpi of the saw or you'll mess it up. The files are cheap, so why not?

I got mine from Lie Nielsen for like $7.50 each so I know you can get them cheaper than that.
I think they are Grobets.

And oh, don't cheap out, get a handle for each file!!

Noah Wagener
04-02-2015, 10:11 AM
... when my Grobets run out.

I've never seen a reference in any book or article to using abrasive files. That suggests it's probably not a great idea.

I know, i know. I just hate consumables and a I suspect an India tri square would last a long time. How long do you expect those Grobets to last. In my limited experience and from what i've read it seems like you'd go through a file a month for each saw. Maybe that is because i am getting saws in poor shape and also practicing filing and the files will last longer when it is just a few passes per teeth.

As far as the sizing, i tried to file a backsaw of about 15 tpi with a 6 inch file and the bottom ot the gullets were very flat. I think i'd like to err on the too small side like the guy writing on that link you posted to. As there really any danger to too sharp corners in a gullet? I have never seen broken teeth on a western saw.

George, i think you have written that you are stocked for life in US made Nicholsons. How many is that? How often do you sharpen?
Unrelated but i have a backsaw that i think has been filed down a lot because it is about the size of a dovetail saw but has a closed handle and the plate is as thick as my handsaw. Would you suggest trying to thin it down? Or did old saws not vary much in thickness like a modern tenon to a modern dovetail does?

Judson Green
04-02-2015, 11:09 AM
And oh, don't cheap out, get a handle for each file!!


Or make your own.

http://www.sawmillcreek.org/showthread.php?227742-file-handle-sizing

http://www.sawmillcreek.org/showthread.php?228083-Shop-made-file-handles

Noah Wagener
04-02-2015, 1:12 PM
I forgot to ask about getting them sharpened. I have read on here that a place called Boggs does a very good job sharpening files. Can they sharpen the corners on three squares and what is the typical cost and smallest run they will do?

george wilson
04-02-2015, 1:35 PM
Noah,I'm not sure what you are asking about thinning saw plates.

Kim Malmberg
04-02-2015, 5:05 PM
Noah, you don't want cheap or cheating files and you don't want to cheat on filing any saw. A saw with a certain PTI will require a file of a certain dimension. It also need to be made for the purpose of filing saw teeth. Yes, you can use cheap and poorly made files but they will cost you more that a decent or good file will. How do I know? I've logged a few hundred saw filing sessions during the last four years. I've done everything from jointing and serious reshaping to just touch ups. I've tried cheap files, intermediately priced files and I've used expensive ones. I donut want cheap or wrong file anywhere near any of my saws. Why? Because I like my saws to perform as well as they possibly can. And using a file too large for the job will create dull teeth. Using a file too small will quickly wear of the file and create gullets which will gather sawdust and clog up your saw. You can try to find vintage quality files or you can buy Bahco files. As far as I can tell the Bahco files are better the any other file available Today.

Noah Wagener
04-02-2015, 8:09 PM
I meant to scrape, file, or sand a plate to make it thinner. I think my backsaw was originally a tenon saw because its handle is closed and the plate is as thick as my handsaw. But the cutting depth is now that of a dovetail saw. I thought maybe i should make the plate thinner. I see dovetail plates advertised as like .02" thick and tenons as like .03. I just do not know if this is something new to sell more saws or if it was traditional. I really can not see why it matters as i think you want to cut to the line and how thick the kerf is should not matter? I can not see speed of sawing being much of a factor for dovetailing

I did scrape a little on it with a file as a scraper. It is very vexing. I will get in a groove where i am getting little curls of steel. Then i stop to reposition the saw blade and all of a sudden the scraper just skates and sharpening does not matter. Can you explain a little more what you mean when you relieve the back of a scraper?

Thanks Kim. I ordered 10 of the 4" x-slim (could not find double xx, hope the corners are small) Bahcos. They cost more than all my saws put together. I hope they last more than the 10 filings i see quoted for typical saw file life. I am surprised that clogging can be a symptom of to deep gullets.

You can get a dozen Grobet 4" x-slims shipped for 39 dollars on Amazon right now if anyone is interested.

Noah Wagener
04-02-2015, 8:52 PM
now i read this essay: https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=10&cad=rja&uact=8&ved=0CE4QFjAJ&url=http%3A%2F%2Fwww.popularwoodworking.com%2Fwood working-blogs%2Farts-mysteries-blogs%2Fthin-plate-saws-more-complicated-than-one-may-think&ei=p88dVfLPDIO1ggSwnYHACA&usg=AFQjCNFAUu2YlcXhrU0aF7wpi5jcTjQFwA
on thickness of saws and i am confused. The author states that 19th century changes to saw design were based on cost saving and not performance. He aims to prove 18th century saws were superior so he builds a bunch of thinner than usual saws. Would not thinner plates been cost saving and therefore the earlier saws thicker? One of these thin saws he made was a 1/32" rip handsaw which he said was unusable to a lot of his students. Isn't 1/32" pretty standard for non backed saws?

What thickness/es did you use at Williamsburgh George? And how did you cut it and drill the holes? I saw a guy Warren Miller punch the holes through a timber crosscut saw that i think would be 1/16" thick. Would that hammering spoil a thin plate in anyway?

Jim Davis
04-06-2015, 12:06 AM
Sounds like that author was either confused or did not write clearly. Perhaps he doesn't realize that the 18th century was the 1700s and the 19th Century was the 1800s.

From 1940 through 1970 handsaw quality went downhill quickly and inextricably.

As for thinner being cheaper, the saw plates tapered from tooth line to back and from heel to toe. The grinding to that configuration made was more expensive than the late 1900s approach, which left the plate about .032" thick all over. Not doing the grinding was a cost saving.

Joe Bailey
04-06-2015, 12:30 AM
Sounds like that author was either confused or did not write clearly. Perhaps he doesn't realize that the 18th century was the 1700s and the 19th Century was the 1800s.

The author -- Adam Cherubini -- is perfectly clear, and accurately states his thesis.

He was building replicas of 18th century saws (the Seaton saws date to the 1790s) in order to prove that they were superior to what Disston (and others) were making in the 19th century (1840s)

Here is a quote from that article:

"See, I thought that the 18th c saw designs were superior to Disston's and I wanted to prove it. I still believe the changes 19th c saw makers made to their designs were based on cost cutting and the switch from a pro furniture market to a less skilled carpentry market."

Chuck Nickerson
04-06-2015, 1:09 PM
I forgot to ask about getting them sharpened. I have read on here that a place called Boggs does a very good job sharpening files. Can they sharpen the corners on three squares and what is the typical cost and smallest run they will do?

Boggs sharpening does a great job; I've run hundreds of files and rasps through them. Their process will not tighten the corners to any real degree.
The price runs about $.30 an inch with no real minimum order. You do pay shipping both ways.
www.boggstool.com (http://www.boggstool.com) Give them a call, they're used to talking to woodworkers.

Tom M King
04-06-2015, 2:07 PM
Save Edge on the East coast sharpens them too, but they do have a minimum number. Both places also sharpen rasps.

It always freaks me out when I see videos of someone teaching sharpening a saw as they use about an inch of the file's length, and then complain about the files not lasting long. They do get dull, but you will get a lot more life out of one if you learn to use the whole length.

Peter Evans
04-06-2015, 7:58 PM
Save Edge on the East coast sharpens them too, but they do have a minimum number. Both places also sharpen rasps.

It always freaks me out when I see videos of someone teaching sharpening a saw as they use about an inch of the file's length, and then complain about the files not lasting long. They do get dull, but you will get a lot more life out of one if you learn to use the whole length.
I do check used old saw files, and frequently the few inches near the handle are still ok, even if the rest is worn down. Sometimes one edge is unused. However sharpening saw files is not worth the trouble, as people said, the faces might be ok, but the edges... Used saw files make good dovetail chisels. Just grind off the teeth for the first couple of inches (do the lot if you want to, I usually just run the file across the grinder a few times to take the sharpness out of the faces), grind the bevel, sharpen and you can clean out those pesky corners with ease. REMEMBER to relieve the corners slightly unless you want blood on your wood. Works for making skew chisels as well.

Stewie Simpson
04-06-2015, 9:46 PM
Boggs sharpening does a great job; I've run hundreds of files and rasps through them. Their process will not tighten the corners to any real degree.
The price runs about $.30 an inch with no real minimum order. You do pay shipping both ways.
www.boggstool.com (http://www.boggstool.com) Give them a call, they're used to talking to woodworkers.

Hi Chuck. What you mention is well worth remembering when discussing the process of resharpening hand files. As an example, regardless of what Boggs claim they can do, once the corner edge of a taper file has been worn down through use, it cannot be resurrected back to its original profile.