Thread: Saw Sharpening at home???

Originally Posted by chook

I will take a trip to the local Sunday markets and get an old saw or two to practice on. i am confident that I could eventually sharpen a bigger saw. But what about a 14 or 16 TPI dovetail saw? I presume that the saw sharpening companies use some sort of machine of jig for these?

chook, saw sharpening companies use machines for all the common sizes, not just the small ones.

you can sharpen your own DT saw as well, the same general principles and steps apply, on one hand they are much easier to do; due to the teeth being smaller you have much less to metal to file. on the other hand what you save in time and effort in that department can be taken up with being more careful in filing and setting the small teeth. depending on your eyesight it can be worthwhile to use magnification glasses/goggles to see them better..

for the same reasons as a hand saw, it is well worth doing your own DT or backsaws


cheers
chippy

I always sent my saws away to be sharpened, as it looked to be so daunting to try and do it myself.

But at the last sydney tool fair I picked up a nice little dovetail saw that needed a bit of work. The saw was cheap so at the same fair i got a saw set and some files and decided to learn.

Sharpening the saw was one of the most satisfying things I've done. There are loads of you tube videos on how to do it and for me, the revelation was how little effort it takes (old saw + new file).

Worth a go...!

I like this one too. It shows everything clearly, which is very useful to a beginner.

Toby

P.S. This is from the same site. Scroll down and pick what you need.

That is an excellent link Toby ... I have come across the Rakemaker part before, but don't remember reading the main one.

Great diagrams.

The one issue I think can confuse the interested newbie is regarding increasing/decreasing rake.

If you only look at articles on saw sharpening then it looks like zero rake is vertical and by increasing rake you lay the tooth over more and more.
And that is what is being described there re: increasing and decreasing rake.

The more universal picture across circular saws, lathe tools etc that was eventually pounded into this thick cranium is that laying back is -ve rake and leaning forward is +ve ... so laying a tooth back further is really *decreasing* the rake ie: making more negative.

The qn of course is whether you unsettle new people by going into it or not.

Cheers,
Paul

PS: this link about sloped gullets has *very* good pictures

ok ... here: http://thesawblog.com/?p=1182

Forget about analyzing the nomenclature and sharpen the saw! Like riding a bike, once you do it it's not scary anymore, it's fun.

Toby

I will have a go at it. But I wonder something. When I look at saw specs they say things like
a rake angle of 14° and an included angle of 60°
I cannot see how I or many others can preserve these angles filing teeth freehand.

I am just clumsy, pessimistic (both?) or is the exact angle not all that critical.

This sharpening thing is something I really want to do. I like the idea of looking after all my tools and jigs and everything else myself. But I don't want to stuff up a perfectly good little saw doing so.

Originally Posted by chook

I will have a go at it. But I wonder something. When I look at saw specs they say things like
a rake angle of 14° and an included angle of 60°
I cannot see how I or many others can preserve these angles filing teeth freehand.

I am just clumsy, pessimistic (both?) or is the exact angle not all that critical.

This sharpening thing is something I really want to do. I like the idea of looking after all my tools and jigs and everything else myself. But I don't want to stuff up a perfectly good little saw doing so.

If your off by a couple of degrees no one will know, and it will cut just fine. Whatever angle you use needs to be consistent all the way down the saw, on both sides, but the precise angle isn't critical. And even a badly sharpened saw will (almost) always cut better than a dull one. Use the little wooden rake angle guides and go for it.
The 60° angle will happen automatically because that's what the file is.

Toby

Originally Posted by chook

I will have a go at it. But I wonder something. When I look at saw specs they say things like
a rake angle of 14° and an included angle of 60°
I cannot see how I or many others can preserve these angles filing teeth freehand.

I am just clumsy, pessimistic (both?) or is the exact angle not all that critical.

This sharpening thing is something I really want to do. I like the idea of looking after all my tools and jigs and everything else myself. But I don't want to stuff up a perfectly good little saw doing so.

the 60° angle is formed with the file. being a triangle its automatic no matter the angle you hold the file. 14° will work for a rip saw (easy to push through) but its too laid back imo, except if you just want to do the front end of the saw for an easier start. any more than around 8°-10° on a rip and the saw can start to feel like driving over a corrugated dirt road as you pull the saw back through the cut

its not too hard to keep the right rake angle, you just have to jump in a give it a go. buy a paddle pop, eat it, keep the stick and drill a hole in the centre of the stick, lodge the stick on the end of the file with file laid back at the angle you want and keep the stick level. with the extended line of the stick, keeping it level with the saw as you file will help you keep the correct angle, easy


cheers
chippy

Or just make your own stick, like this:

Blokes like Ch!ppy who sharpen saws every other day, can maintain a constant angle with their eyes closed, but you will probably find the stick helps a lot at first. It's essential for me when re-forming badly mucked-up teeth that required a heavy jointing. I usually dispense with it when sharpening, because it gets in the way if doing a crosscut saw, where the file has to be angled. If you 'set' the file in the first tooth, with a firm & comfortable grip, then don't change, & don't stop til you reach the end, the angle should remain constant.

I have found that using a guide stick for the sharpening step helps with very small teeth (20 tpi & finer) because the gullet is so small, it doesn't register the file very well, but with 15 tpi & coarser, I don't have too many problems (most days!).....

Cheers,

Originally Posted by pmcgee

That is an excellent link Toby ... I have come across the Rakemaker part before, but don't remember reading the main one.

Great diagrams.

The one issue I think can confuse the interested newbie is regarding increasing/decreasing rake.

If you only look at articles on saw sharpening then it looks like zero rake is vertical and by increasing rake you lay the tooth over more and more.
And that is what is being described there re: increasing and decreasing rake.

The more universal picture across circular saws, lathe tools etc that was eventually pounded into this thick cranium is that laying back is -ve rake and leaning forward is +ve ... so laying a tooth back further is really *decreasing* the rake ie: making more negative.

The qn of course is whether you unsettle new people by going into it or not.

Cheers,
Paul

PS: this link about sloped gullets has *very* good pictures

ok ... here: I slope, you slope, we all slope gullets… – The Saw Blog

Déjà vu

Toby