Thread: Saw file guide

Originally Posted by MartinCH

Have two questions for the forum.
I used 20 degrees for the fleam- is that pretty reasonable for cutting hardwoods?

Is there any significant to more radical approaches such as the acme style sharpening? - which I think is somelike 30 degree slope, 30 degree rake and 30 degree fleam.....

Just curious now that I could "potentially" try them....

The amount of fleam is a trade-off between sharpness and edge strength. 20° is pushing it a little and probably too much for the hardwoods. 15° might be better for edge life.

The ACME120 saws produced by Disston actually followed similar angles to any other saw. The difference in the ACME range was two-pronged. The teeth were not sharpened with a conventional triangular file as the teeth were at a steeper angle than 60°. In this regard they were more like Japanese saws and required a feather file or a cant saw file. The ACME saws also had no set. They were only suitable for seasoned timber and had a greater amount of taper grinding so they could run without set.

If you were chasing an alternative you could have a look at the thread below.

Sloped Gullets (woodworkforums.com)

Regards
Paul

PS: For sloped gullets 20° of fleam is more appropriate as the file handle held low changes the rake angle.

Ok will try a 15 degree slope see - see what that does and if I can knock set down as well and leave my knocked from scrap guide alone...

The thread raises some more questions....
DEST is double extra slim? - are these also the needle file sometimes referred to?

Have you tried the idea of running a file "lightly" over the top of filed teeth to even out heights?
I was binding in repeatable locations when I freehand sharpened My best guess was this was caused by a couple of teeth lower than the rest which caused the later teeth to dig in. A light file might have helped smooth out the binding and easier than resharpening..


Based on comments on Simonds 51 saw there is value in the high taper no set idea. A bit of lost art for now. I not sure my wife, as generous as she is, will be easy convince it a good idea to send $1500 to but an antique saw to try out ]

Did you keep the Simonds 51?

Originally Posted by MartinCH

Ok will try a 15 degree slope see - see what that does and if I can knock set down as well and leave my knocked from scrap guide alone...

The thread raises some more questions....
DEST is double extra slim? - are these also the needle file sometimes referred to?

Have you tried the idea of running a file "lightly" over the top of filed teeth to even out heights?
I was binding in repeatable locations when I freehand sharpened My best guess was this was caused by a couple of teeth lower than the rest which caused the later teeth to dig in. A light file might have helped smooth out the binding and easier than resharpening..


Based on comments on Simonds 51 saw there is value in the high taper no set idea. A bit of lost art for now. I not sure my wife, as generous as she is, will be easy convince it a good idea to send $1500 to but an antique saw to try out ]

Did you keep the Simonds 51?

Martin

It looks like you actually read the thread I linked. Well done as they do drag on a bit at times.

To answer your questions, "Yes" DEST is double extra slim taper, but that is not a needle file. Needle files are smaller and finer again being suitable for ppi greater than 12. Up to 12ppi a 4" DEST file will work. As the tooth number decreases you can use larger files. Bear in mind there is some overlap of file sizes. In years gone by there was a huge range of sizes commonly available, but today it seems much more limited. we have discussed on the Forum ad nauseam the lamentable lack of quality. New old stock is your best bet, but otherwise there are a few alternatives. The quality appears to drop off as the file size becomes smaller, possibly pointing to a sloppy method of machining.

Bacho are a brand that has some standing, but I will let others wade in with file recommendations as they have probably purchased more recently than I.

The steps in sharpening an old file are jointing, shaping, setting and filing. The jointing step is most important. You can just run a flat file (fairly fine seems to work better than coarse) over the top of the teeth just hand held, but most people use some sort of jig to hold the file at 90° to the saw plate. You should file until every tooth has a flat spot indicated by a bright tip. The lowest tooth will be just nicked by the file while the tallest tooth will have a large flat. These are a couple of commercial jigs for holding a small file:

P1060797 (Medium).JPGP1060798 (Medium).JPG

and a couple of home made jigs:

P1060799 (Medium).JPGP1060796 (Medium).JPG

I have a diagram somewhere of the first jig. I will try to find it as it is easy to knock up. Then you can shape the tooth before setting and sharpening.

On the no-set saws, this is a very specific application and relies heavily on the taper grinding being more extreme, something that is done at the point of manufacture and very difficult for a hobbyist to replicate with our limited resources.

I do have the Simonds No.51 saws still. One saw came up a treat and cut beautifully while the other bound in the cut. When I checked the toothline, which I should have done first up , I realised it had a very slight wave in it. That was the issue and I can correct it, I think, but I have not got back to it as other projects have taken priority. That one is way down the list.

One thing I slightly mis-led with on the ACME 120 saws is that they did have a very acute amount of fleam so they were different in that regard too. At some point in Disston's history they did actually dispense with the tall tooth requiring a special file (they called it a cant saw file with a "safe" back. Ie. no teeth) and used conventional, for Western saws, 60° teeth.

One other thing is, after you have finished the sharpening, you should run either an oilstone or a worn file gently down each side of the tooth line from heel to toe. I do this while still in the vice (the saw not me) as my vice is the full length of the saw, but others lay the saw flat on the bench to do this and then flip the saw for the other side. This is to remove any irregularities that ocurred when you set the saw.

Regards
Paul

PS: I wouldn't change the fleam at this point, but leave it until you next need to sharpen. Don't be afraid to experiment a little.

This is the jointer jig I mentioned before:


Jointer jig.png

It is from a publication more than 100 years old! The one I made use two screws instead of one to secure the file.

Regards
Paul

Hi Paul,

Not going to refile at this, the saws in are working well, but next time I try and with slopes and a needle file see if that enhances - and make sure I joint first. I was also intending a purchase another saw pull an old Stanley out of rack... If I get the saw I might post it as I noticed that you like Sinonds saws andI cannot quite identify this one despite your rather extensive thread...

For better or worse I have stropped my saw on powered disc - (note I run reverse to the fleam and can reverse the strop to suit each side... Overdoing strops works well for chisels and plane blades and I figured it might work for saws as well... Hasn't harmed the saws polishing the outside....

Regards

Martin

Martin

By all means put up some pix. All the saw tragics love saw pix and truthfully without the visual evidence identification is very difficult.

Regards
Paul

Martin, Paul has already responded to your questions very thoroughly, but I would point out that needle files are only needed for very fine teeth >15tpi. They are good files & last a long time compared with the 'regular' files offered these days, but they cost more and are very short, which makes the job a bit more tedious. They are also very sharp and so benefit from something on the end (like your nifty little file guide).

If I need a file guide I use a simple stick guide: Filing guide.jpg
These are so easy to make for any angle - not as precise as the things you can by, but enough to keep your filing consistent.

I just gave my thoughts on flram & rake angles in Mountain Ash's thread, which started almost simultaneously...

Cheers,

Thanks Ian

- first time I filed a saw I used wedged blocks, but- they fell off and generally annoying . No doubt part issue with my use of blocks was that I was totally inept.

I will keep to the 15 degree to 20 degree flem range. That where I am and match advise and the saws are going well. Learnt a bit about high flem, taper ground hard saw. Perhaps enough to decide one day to try and make one - (for fun)



Taught a friend how to sharpen his saw with only demonstrating a few sharpening strokes. My friend was delighted, with the result, surprised how fast (though pine) a nice sharp taper ground panel saw is - sliced some pine in "3 strokes" I am advised...



Since then have also demonstrated what a sharp gimlet can do. This has increased the surprise .....

Sharpened a mitre box saw - it was binding a tad the end of cut, guessed was from a too high tooth. Particularly as issue was in part of the saw that will not see sawing action in mitre box. Tried that note that suggested lightly joint the sharpened teeth. Seems to reduced the issue and did not appear to effect cutting to any noticeable extent ..

Originally Posted by MartinCH

......Learnt a bit about high flem, taper ground hard saw. Perhaps enough to decide one day to try and make one - (for fun). ..

Martin, making saws is a very dangerous undertaking - it can lead to a mild obsession (damhik!)....

It can be a lot of fun, though, & opens a whole new world of tool-making, so go for it. Getting hold of saw plate will probably be your main concern, it's simply not available here in small quantities. I doubt you'll be able to buy any plate tempered to the hardness of a Disston 77, and re-hardening & tempering thin stock like saw plate would be well beyond the capabilities of even a well-appointed backyard workshop, methinks. If I wanted to make another saw or two, I'd buy a pack of blue-tempered 1095 shim stock, it's the least costly way to get several saw's worth of plate. It's tempered to a level that's on the hard side for saw plate, but not as hard as a 77, that's a few more notches up the scale.

The most readily available brass in this country is C385, which is a 'machinable' brass & not good for bending, but you can get softer alloys with a bit of effort. I've never bent a brass back, so can't say if 260 brass (a lot more malleable than 385), would take the full bend without cracking - anything I've read about bending backs usually talks about annealing at least once during the process. Too much fussing for me - slotted backs work every bit as well despite claims to the contrary, and easier to make. I made a crude jig for my drill press and use a slitting saw to slot the brass for backs.

It's a bit odd that saws tend to get ignored when it comes to keeping them sharp. Folks who'll fuss about honing a chisel or a plane blade the second it starts to dull will go on pushing dull saws for months. I suppose that's because the thought of sharpening your own saws is intimidating, but once you discover it's not that difficult, you'll be far less inclined to put up with a dull one. I read somewhere years & years ago that "even a not-so-well-sharpened saw cuts way better than a dull one". I think that's pretty true....

Cheers,

Hi Ian,,

thanks for all this- I started budgeting what a saw would cost and I must say secondhand saws I own where very cheap.. The sum is not atrosiously expensive but I was over $100 in part and tools..

So perhaps I should refile a cheap hard point refile to 45 degree flem and maybe taper the plate. _(I made the world's crudest surface grinder when I refurbished some hand planes- the idea of flattening a no 7 for multiple hours had limited appeal)... The craftright saws is a grand total of $6.98 so limited bank damage.. Then I can see if with finishing or obtaining better steel..

Originally Posted by MartinCH

So perhaps I should refile a cheap hard point refile to 45 degree flem and maybe taper the plate.

Martin

The "hardpoint" saws are called that for a reason. The teeth are induction hardened and a file won't touch them, which is why they are discarded when blunt. You may be able to use the plate if you cut off the teeth as they are hardened only for the length of the tooth itself. Normally this area is easily recogniseable as it is discoloured from that process. having cut off the old teeth you will need to cut in new teeth. The easiest way to do that is with a thin cutting disc in an angle grinder.

Many of us have talked about doing this, including myself, but not too many have tried it. This is not because it is hard to do, (no different to cutting the teeth into a new piece of saw plate), but because the steel plate remaining is of an unknown quality. Actually, f you get to this, the ease of filing will be some indication of how suitable the steel is. easy equals no good: A little bit of a challenge would be encouraging.

Good luck with the venture. I eagerly await the outcome as I have several saws kept for this purpose before I railed against the throwaway culture. Until now they have been a long way down the list of priorities.

Regards
Paul

Hi Paul

Using the disk cutter is a good idea. I can use the existing teeth spacing as guide before fully removing the teeth.
What could go wrong??

and yes lost of ways to stuff up..

Hi MCH. I did as Paul described to a modern, plastic handled, Sandvik back saw. Worked well and I replaced the handle at the same time. Blackburn Tools (USA) have printable templates for a range of teeth sizes. Just tape the paper in place on the blade, and file straight through.

Originally Posted by MartinCH

Hi Paul

Using the disk cutter is a good idea. I can use the existing teeth spacing as guide before fully removing the teeth.
What could go wrong??

and yes lost of ways to stuff up..

Martin

That would probably work. This is the link Mountain Ash referred to:

Blackburn Tools - Saw tooth spacing templates

Also I realised my previous post could be read wrong because of some bad phrasing. Cut the old teeth off with the angle grinder and thin cutting disc. New teeth are formed with the file. New teeth are particularly demanding on the file and in particular the corners, which are the part that degrades first. Paul Sellers had a technique where he uses a fine tooth hacksaw ((probably 32ppi) to do the bulk of the vertical cutting thus saving wear on the file corner.

(14) Recutting and Resizing Saw Teeth | Paul Sellers - YouTube

Note that he removes the set on the hacksaw blade first by an easy method.

Also be aware that there are a multitude of different ways to go about cutting new teeth. The right way is whatever works for you. I expect that there might be a few more suggestions and tricks from other Forum members on the ways they have found works for them. I have so far only done all the tooth shaping with the file, but the next set of teeth I file in from scratch will use the Sellers method to give it a go.

Regards
Paul