Saw Sharpening - uneven gullets

[Joe]

I've been practising sharpening an old Tyzack tenon saw, which is 13 tpi, using a rip profile. I've been lightly jointing the teeth and then filing to remove the flats in order to try and get teeth of an even height. The problem is I keep ending up with very uneven looking gullets. Can anyone offer me any tips for avoiding this? If the gullets are uneven does this mean the teeth are different heights too? I want to try and get the hang of this before I need to sharpen my Gramercy dovetail saw (a lovely, lovely saw, now stocked by Ray Iles) - I'm terrified of ruining it!

Thanks

Joel

 

[Digit]

What do you mean by uneven Joel? Uneven in spacing or in depth?

Roy.

 

[Joe]

Hello Roy. They are uneven in depth. Because the teeth on the saw started out at different heights, the size of the flats after jointing are unequal, so I try and compensate by pushing the file a bit harder in the necessary direction but what I end up with still looks like a dogs breakfast.

Joel

 

[Digit]

Two solutions offer. One is to remove the teeth and recut, one I dodge, and the other is to clamp the saw between two piece of angle Iron and cut down till the file just touches.
From your description it sounds like you are not using a proper saw file, if not I would suggest you buy one.
If desperate have the saw professionally recut and stick to sharpening from there on.
I've only ever recut one panel saw from scratch and that was enough for me! After that I simply stuck to sharpening and setting.

Roy.

 

[Racers]

Hi,

13tpi is a bit small to start, I have worked myself down to thet sort of size. have a look at Bugbear templates an info http://www.geocities.com/plybench/saw_sharpen.html you might be best filing them all off and starting again. I did one and is not to hard, just start slowly with a couple of file strokes for each tooth and gradually deepen them keeping an eye on them to make sure they are even.

Pete

 

[Joe]

Thanks Pete & Roy for the advice. Think I'll try the angle-iron trick first.

Joel

 

[Peter Evans]

One way to fail is to try and get rid of half the flat on each tooth as you go down the saw.

1. Suggest filing a fixed (1-3) number of strokes all the way down the saw - every tooth to shape the teeth. Some flat remains on the teeth, or many of them. I assume the teeth have been jointed.

2. Check the gullets are even, if not touch up those teeth to get gullets even. This will also deal with any excessive flats in most cases.

3. Set the saw very lightly (or leave the set as is, ie add no set to the saw, at 13ppi you will get 1-2" cut with no set for dovetails or tenons).

4. Joint lightly, now sharpen the teeth removing _almost_ all the flat. Knock the burr off the teeth with a piece of soft pine, and see if there are still any flats left (the filing burr can look like a flat on the top of the tooth). If there are touch up those teeth. Run an oilstone down each side of the saw to remove any side burrs, or simply saw a bit of pine to get rid of them.

If all teeth are the same height and set, a bit of difference in size should not cause any problems, and will eventually go with repeated filings.

For 13ppi you should be using a 5" double extra slim taper file. a coarser file will give you rounded gullets - and smaller teeth).

 

[bugbear]

I've been practising sharpening an old Tyzack tenon saw, which is 13 tpi, using a rip profile. I've been lightly jointing the teeth and then filing to remove the flats in order to try and get teeth of an even height. The problem is I keep ending up with very uneven looking gullets. Can anyone offer me any tips for avoiding this? If the gullets are uneven does this mean the teeth are different heights too? I want to try and get the hang of this before I need to sharpen my Gramercy dovetail saw (a lovely, lovely saw, now stocked by Ray Iles) - I'm terrified of ruining it!

Thanks

Joel

Not a problem. You're following the correct procedure, although if you're starting out, I'd advise bigger teeth for a practise saw.

I'm assuming your tooth tips are in a nice line, since jointing, then filing away the flats generates that happy condition. Your saw almost certainly cuts pretty well.

Your uneven gullets (and hence teeth) are caused by doing too much work on either your first pass or your second pass. You have to use skill and judgement to ensure that you do the "right" amount of work on each of the two (handle left, handle right) passes.

Alternatively, you can do what I still do (to some extent). Instead of doing two passes, which must pair up exactly, do more passes, e.g. 6 (3 from each side), removing less metal. You can then gauge more easily your progress, and alter your action (and pressure) accordingly. As your experience grows, the numbers of passes you require to get even teeth (and gullets) will diminish.

I have a rather extensive store of saw-sharpening information here:

http://www.geocities.com/plybench/saw_sharpen.html

and this issue was discussed in some detail recently, over on woodnet:

http://www.forums.woodnet.net/ubbthread ... t=all&vc=1

BugBear

 

[Joe]

Fantastic. Thanks to everyone for the feedback.

Joel

 

[Benchwayze]

I've been offered two Spear & Jackson, saws (Rip and cross-cut) which look to be of 1960's vintage.

They have never been used, are straight as dies, and scary sharp.
Thing is, the guy wants me to make him an offer and I have no idea what these might be worth. He claims not to know either... 8)

I don't want to buy to collect but to use and naturally I don't want to pay more than I have to!

Any ideas on value of these things? Anyone?
Thanks in anticipation.

John

 

[pedder]

I've been offered two Spear & Jackson, saws (Rip and cross-cut) which look to be of 1960's vintage.
Any ideas on value of these things?

Hi John,

Only have ebay experience: from 7 for a mild rusty saw to 20 for a near mint.

Cheers Pedder

 

[Benchwayze]

Cheers Peddar.
£30.00 the pair in that case. They are near mint!
regards
John