Thread: [nzl] saw file sizes, naming, and source

Hi

Not a source in NZL, but this page on Lee valley.com should help you with file sizing Bahco Saw-Sharpening Files - Lee Valley Tools

Also, this passage from the Lie Nielsen site may be useful
"For saw sharpening. To choose the right file, size it to the tooth. Ideally, about half of the cutting surface of the file will be in contact with the tooth -- half of the file will be in the gullet and the other half unused. When you rotate the file to get a fresh edge, it will be uniformly sharp. If you use a smaller file, only some of the new surface will be fresh and the rest dull."

this page from a German retailer (who ships world wide) is specific to the retailer's saws, but with a bit of cross referencing you can see what size file is recommended for what tooth pattern (rip or cross cut) and tooth pitch https://www.fine-tools.com/euroscha.html


hope the above is helpful

yeah i found that lee valley page. (the shipping from there is about $30nzd for two files btw so i ruled out buying direct) but there they're called 6" 8" slim, x-slim, and elsewhere they seem to have names like "4-186-04-2-0" and i havent managed to decipher what those numbers mean exactly.


from the second page you linked, i'm guessing the names are "width-length-cut-something-something else-something else again" ?


i _believe_ i'm looking for a file with a tpi of about 60 tpi @ 6" for the backsaws saws, and about 38 tpi @ maybe 8" long for the handsaws. I couldn't find a 38 tpi file on trademe at all though. I'm really keen on finding a good source for them if possible, being a consumable if i can avoid shipping costs it'd be good. Otherwise i'd need to just order in higher quantities but that's gotta get past SWMBO

aha ! just found https://www.woodworkforums.com/attach...5&d=1435466809 and https://www.woodworkforums.com/attach...6&d=1435466811

so that naming is entire bahco specific and apparently it's just model numbers, nothing to do with anything. gah.

There is a pretty good reference here:
Blackburn Tools - Triangular saw files
Plus all you need to know about tooth geometry here:
Blackburn Tools - saw tooth geometry

Sirex, how I wish there was a simple answer to your question(s)!

It's hard enough as a beginner to negotiate the intricacies of sharpening saws, but the problem has been compounded these last 10 or 15 years by major issues around files. If you are really interested, there are several threads on the topic, but to save you the tedium of searching for threads & reading through pages of stuff, much of which isn't relevant to your immediate needs, here is a synopsis.

First, what Ian said about sizing the file so that it half-fills the gullet is correct, but there's more to it than that. Files not only vary in length, they vary in the radius of their corners. This really matters when you get down to small teeth, because a file with a large-radius corner will produce large, round-bottomed gullets with tiny little teeth.

My advice before you go much further, is to download this pdf. It has a table (also available on the Lie-Nielsen site among others) of file sizes matched to numbers of tpi. My apologies if you are a younger person with no familiarity with Imperial units, but "teeth per inch" has been ingrained in my tiny brain for 60 years. When you talk about 12tpi, I get an instant mental picture of what that saw looks like & what it's likely to be used for, but if you say a saw has a pitch of 1.66mm, I have to do some mental gymnastics and convert that to tpi, & think "Oh yeah, that's 15tpi"!

Manufacturers used to make files in set sizes that you could rely on, but if you buy so-called "American pattern" files these days, you will sometimes get files that meet the specifications for their size, often not. Either poor quality control, or confusion with European standards, or both, means that when you buy a file that is supposed to be 4", extra-slim, tapered, it may or may not be up to the tooth size it should handle according to the tables you read. I put the commas in deliberately, to emphasise that the "extra slim" refers to the file body, not the taper (they are all tapered more-or-less the same). As you progress to shorter files, and from 'slim' through 'extra slim' to 'double extra slim', the files get thinner, the teeth get slightly finer, and the corners sharper. So that's why the table in the primer I pointed to above recommends a 4" 2xES (=double extra slim) file for teeth of 13-20tpi. In fact, you will be lucky to find a supposed 4" DEST file that is sufficiently fine to do 18 or 20tpi these days, but fortunately, few people have that need!

And as to reliable brands? I wish I could advise you that brand X is good, but the truth is, you take pot luck with any new files. Pretty much all of the files you are likely to get your hands on are made in just a couple of countries, & it seems the policy is to simply make file-like objects, and to hell with quality. The most common faults are 1: Huge inconsistency in corner radii, not only from file to file of the same ostensible size, but even on the same file! 2) They are generally far too brittle for saw-sharpening, and shed corner teeth in patches. This makes the files 'catch' & it's extremely difficult to make smooth, consistent strokes when sharpening, something that is essential if you want clean, consistent teeth on your saw. I also strike the opposite - files that are so soft they have no teeth at all after a few passes on saw plate. I had an example of that yesterday, in fact, and it was a Bahco file. Most of the Bahcos & Pferds I've used over the last few years were too brittle, so I suppose it made a change...

The best saw file I've used in a while (apart from some new, old-stock files), which had the right balance between hardness & brittleness was a Japanese-made file. It came to me by a roundabout route, so not sure where you'd get them from. It has a drawback in that it's parallel-sided, which can be a nuisance, because the taper does allow you to see better where you are placing the file each time you change to the next tooth. It's really only a problem with finer teeth (& it depends on your eyesight what is 'fine'!) not so important with larger ones, once you get the hang of sharpening.

So I hope I haven't put you off saw-sharpening, it's a skill that's well worth acquiring if you want to be a hand-tool user. "Western" saws were neglected for a very long time, because the blokes with the real hand-saw-sharpening skills had begun to die out by the early 1970s, so throw-away saws dominated the market for a couple of decades. Thankfully, they've made a big comeback during the last 20 years, but to maintain that impetus, we've got to get adequate files so people can sharpen them easily. I live in hope that we'll see the emergence of a few 'boutique' file makers sometime soon......

Cheers,

after some hunting about, i found a place that actually has a few bahco saw files in the wellington area.

WR Twigg in lower hutt, has 4-186-04-2-2 files for $9, and a few larger sized ones, which is much better than the $17-22 on trademe especially considering this is with a handle on it and those are without. I'll go back for a larger sized one once i've decided which exactly i need.

In case anyone else stumbles over this thread, some of the other product codes which they seem to carry that may be useful (2 were out of stock at the time so i'm not certain on those) are:
4-187-06-2-2,
4-186-06-2-2
4-187-05-2-2
5-186-05-2-2
4-186-04-2-2
1-160-04-1-2
2-472-16-1-0
2-470-16-1-0

Sirex

This is a link to a file survey that was conducted on the Forum. You can see it as a sticky at the top of the hand tools section.

SAW FILES TEST REPORT - extensive testing of 23 saw files by 3 experienced filers

I would comment that there are no cheap files. You would be wasting your time. Also, unfortunately, some expensive files are no good either. A file needs to be a touch over twice the width of the tooth you are sharpening. In principle you need a different size file for every tooth configuration, although a little bit of overlap is allowable. A rip tooth will require a slightly larger file than a crosscut tooth of the same ppi as the rip configuration makes the back of the tooth longer.

The chart below may assist:



Regards
Paul

Apologies. I am struggling to load the chart to which I have made reference in the previous post. For some reason it won't play the game. I will keep trying.

Regards
Paul

Originally Posted by Bushmiller

......This is a link to a file survey that was conducted on the Forum. You can see it as a sticky at the top of the hand tools section......

Paul, there seems to be a problem with the 'sticky', I can't download the chart Brett made up (I use Firefox for my browser). If it has vanished into a black hole like lots of pics from the same era it will be a pity 'cos it contained some useful info for quick comparisons. I'll look into what's going down with it & see if one of the super-mods can restore it to health.

If it can be restored, you need to be aware that some of the info is getting out of date. Things have changed a bit in the saw-file world with respect to local availability of sizes & brands, mostly going from bad to worse! . Fewer stockists & a smaller range of stocked sizes seems to be the go everywhere. I haven't had a truly decent (new) file from any of the name-brands these last few years except the Grobet Vallorbe needle files I use on small teeth (15tpi +). I went to stock up on these a couple of months ago & the local AJS where I've always bought them was out of stock - I back-ordered them, but haven't yet heard from them, which is a worry, either they're taking an unusually long time to find their way here from Switzerland, or I've been forgotten. I need to stir them up!

I've struck a few good files, occasionally, with consistent corners that have the corner radii appropriate to their nominal size, which lasted long enough to get some useful work out of them, but they have mostly been 'new old stock' which is a rapidly-diminishing resource! Both lots of supposedly 'good' brands I've tried in the last 18 months or so were sheer rubbish - I couldn't print what I really think of them or the brand-names without risking a libel suit! I have tried a couple of Japanese files, both of which came to me via someone else, to 'see what I thought of them'. Both were good files, with very fine corners (for their length & width) and both gave a good account of themselves on hard sawplate. They are not perfect, however, as they are un-tapered. If you've ever wondered why saw-files are tapered, one reason is that you can see around the thinnest part enough to place the file accurately when going from tooth to tooth. This is almost essential for me on small-toothed saws (>15tpi). For larger sized teeth (<12tpi), I don't have too much of a problem with straight files, but I definitely need all the help I can get with the finer teeth. I don't think that situation is going to improve, either - the new specs I got a couple of months ago made only a marginal improvement.

We battle on....
Cheers,

Ok. This was the only way I could download the chart. I printed off a copy,photographed it (not very well I'm afraid), put it on the computer and downloaded it here. I hope.

P1020750.JPG

If you can read it (enlarging will be necessary) you can see the dimensions of the files. Maybe.

You would be able to see for example that the triangular dimension for a 6" DEST file is in fact the same as that for a 3" regular taper file. For filing purposes the longer file will be preferable as smooth steady strokes can be achieved more easily. Generally the longer file the better, but by the time you are filing teeth finer than 12ppi you will be down to around 3" to 4" files. The finest tooth saws require needle files.

Regards
Paul

Originally Posted by Bushmiller

Ok. This was the only way I could download the chart. I printed off a copy,photographed it (not very well I'm afraid), put it on the computer and downloaded it here. I hope.

P1020750.JPG

If you can read it (enlarging will be necessary) you can see the dimensions of the files. Maybe.

You would be able to see for example that the triangular dimension for a 6" DEST file is in fact the same as that for a 3" regular taper file. For filing purposes the longer file will be preferable as smooth steady strokes can be achieved more easily. Generally the longer file the better, but by the time you are filing teeth finer than 12ppi you will be down to around 3" to 4" files. The finest tooth saws require needle files.

Regards
Paul

Thanks Paul[emoji106]

Originally Posted by Bushmiller

Ok. This was the only way I could download the chart.......

Paul, I can't read the fine print! I didn't know that was the chart you were trying to upload - here's a pdf of it that I think is marginally better. You should be able to read the printing when you blow it up a bit....
File sizes.pdf

I guess your main point was to show how the sizes mix & match with the 'slimness'.

Cheers,

Thanks Ian

There was a twofold reason. The first as you identified, the relationship between length and slimness: I took an extreme example, but a better one would be that a 6" slim taper file is equivalent to a 7" EST file in the width of the triangular face.

The second point is that you can measure the length of the edge of the tooth, double that and add a fraction of a millimeter and you now know what width file you will need. The only saw I had in the house was a 12ppi that I cleaned up last night and brought in to dry. It has not been sharpened so the teeth are not as long as they would be once super sharp (they have slightly rounded tips at the moment) and I measured just under two mm. So I called it 4mm and looked up the conversion which gave me 5/32". Looking at my chart the only files to suit are a 3" slim taper or a 4" double extra slim taper.

Having said that ( ), I can't read the fine print in my chart or your chart .

However I have found a link on the web which will be clear. Looks like it comes from Heavansabove (thanks Peter).

http://i148.photobucket.com/albums/s...nsabove/13.jpg

This chart shows more clearly than my description the dimensions to measure:

lie-nielsen-file-sizes.jpg

The sizing is from lie-Nielsen, but the files looks a little on the large (fat) size to me.


Regards
Paul

Paul, I no longer get too fussed about having the file width slightly more than double the length of the side of the tooth. Once upon a time I did, because it seemed to be simple logic that you should wear the file down evenly as you use each corner - no wasted file! However, in practice it doesn't work out that way at all, because the corners always give out long before you have caused anywhere near as much wear on the sides. I don't remember it as being as bad with the saw files of old, but it is certainly very noticeable with the current crop of lousy files we get foisted on us.

So because of the inconsistent & fat corners we are served up by careless manufacturers, what I am most concerned about when I go to sharpen a saw, is finding a file with the right corner geometry to suit the tpi. I always have about 6 or 7 saw files on the go at any one time, mainly because of that. I break out a new DEST 4" to sharpen a fine-toothed saw only to find its corners are more suited to much bigger teeth than the ones I'm about to tackle, so I set it aside for bigger teeth. It's a pest, really, because I like to use the longest file that will do the job, (fewer actual strokes for the same amount of metal removed, less moving of the file & less chance of making misyakes like missing a tooth or worse, doubling up). So I'd much rather use a 6" than a 4" file on a 10tpi saw, for e.g., but that's all some of the supposed 4" DEST files I have are good for.....

Cheers,