Saw sharpening

[TallMikeM]

was thinking about this the other day (which resurfaced on brtisih reds winter thread) as I put yet another new blade in my trust bowsaw. Now, bowsaw blades aren't exactly expensive, but is it possible to resharpen them at home? What sort of tools would be required? files, jigs etc?
I may also be able to get my mitts on a crosscut saw, but I'm almost certain it'd need resharpening and it'd be nice to have the skills to do it.

 

[Aaron]

Unfortunately most of the ones you buy from hardware stores or B&Q these days have super-hardened teeth that are hard to re-sharpen - they are manufactured as disposable items as most people cant be bothered. To my mind this is a complete waste in the days where recycling plays an increasing contribution to conserving the environment.

 

[British Red]

Well Mike, I'm far from expert but there are a number of things to consider. The tooth set may need to be adjusted. On smaller blades there is a plier like tool to adjust the set of teeth to give a perfect kerf (this is the amount of "bend" the tooth has). On a crosscut the teeth are adjusted with a hammer and a saw set.

The teeth then need to be levelled since if some have worn more than others, and then re-sharpened to a proper "v" profile. The tool that assists you in this is called a jointer (together with a file).

Then one can adjust the raker teeth - these should be checked with a raker gauge.

I have managed to source some old tools designed to do this (jointer, saw set, a couple of sets of the pliers type tools - but no raker gauge yet).

[imghttp://farm3.static.flickr.com/2318/1796065714_d90fcf432f.jpg[/img]

There are a few web based tutorials around of how to set and sharpen large saws (Weaver has also been kind in guiding my baby steps) although none seem totally intuitive to grasp. So I plan a little "experimentation" to see what I can come up with.

Red

 

[FGYT]

always remember my dad n Uncle shapening their saw regularly
this is the normal carpenters & chippy saws
but for years now hes used the disposable ones has a big stack of them as he uses them as Breese block saws when not good enough for wood

he has a few of the big logging type saws in the garage from some where but ive never seen them sharpened or used

if you want a challange i just picked up a load of old gardening tools freecycle and theres a couple of hand saws there very rusty etc which are for the tip

ATB

Duncan

 

[weaver]

Never had the honor of correcting Red before, but I simply must.

Joint first.
then set the teeth
then sharpen
Then adjust rakers.

You are almost there grasshopper.

 

[mr dazzler]

You need to also remember that if the saw is real badly manged up you will need to reshape the teth in between the jointing and setting stages. In extreme cases even remove all the remaining "teeth" and reshape a whole new set, even altering the PPI at this stage
Major problems with old saws is
1/ Failing to joint the teeth to level tips and just sharpening each tooth equally. This eventually results in a concave toothline as the middle teeth wear more than the end ones
2/ varying rake angles (caused by inconsistent filing)
3/ no set
4/ too much set
5/ Uneven set
6/ Bad pitting near the teeth, renders the saw vitrually useless
7/ Too many broken teeth
8/ Shoddy attempts at hammer flattening of a dented blade
9/ bent/cracked/warped blade
Eclipse setting pliars are fine, you get consistent results every time
Also remember to always set the teeth in the same direction (ie lefties to the left, righties to the right) If you try to reverse it youll snap your teeth off trust me I did it
If you want an agressive cut, shape teeth with a very steep rake angle (like a Japanese rip saw) BUT the saw will be harder to start. I'd recomend practising filing a rip saw first as you basically file right across at 90 degres.

 

[British Red]

Never had the honor of correcting Red before, but I simply must.

Joint first.
then set the teeth
then sharpen
Then adjust rakers.

You are almost there grasshopper.

I'll figure it out eventually

I wondering if Duncs dad want to get rid of those "big logging saws" - they must clutter the place up something terrible

Red

 

[Toadflax]

If it is of any use, I remembered an old book from 1946 which has some info on saw sharpening. Send me a PM if you can't read it.

Mods please warn me if this is likely to be a copyright problem.


Geoff

 

[FGYT]

I wondering if Duncs dad want to get rid of those "big logging saws" - they must clutter the place up something terrible

Red

you would have to get past the Cluttter of Norton,s BSA,s Rope and 50yrs of an old builder squirreling away anything that looks usfull
I know where they are but getting at them is a differnt matter Fransis barnett any body with fairing

ATB

Dunc (whos own garage is now just as impenatrable )

 

[British Red]

Shame - I was gonna offer to trade a bottle of malt for a good one in the 5-6' range