When you don't joint the teeth each time you file

[MarvW]

Hi saw sharpeners...

This is an example of what will happen if you don't joint the teeth before filing your saw.


Jointing the teeth each time you file, gives you a flat on the point of the teeth to use as a reference as to how much to file off of each tooth. Jointing also makes all the points even with each other and creates a straight tooth edge, unlike the poor old Atkins saw in this picture. I suggest that you joint even if you are only touching up dull teeth.

The teeth on this saw all have sharp points, but trust me, this saw does not cut better than if it was only dull.

Can this saw be fixed? Yes it can. But, a lot of the blade will be filed away during the early multiple stages of jointing and filing. The saw could be retoothed on a retoothing machine but you would lose more of the saw blade than if you do it by hand.

For this particular saw, the first jointing would only leave flats on the teeth on about 4 or 5 inches at the back end. The rest of the tooth edge should not be jointed. Other saws will be different, no two will be the same. Keep jointing and filing in small stages until the jointing leaves a flat on all the teeth. Only file those teeth that have flats. When filing the flats, only file off half of the flat on every other tooth, then file the other half of the flat from the alternating teeth. Whether you want the saw to be a rip profile or crosscut, a saw like this must be reshaped by filing straight across and file with the rake angle you will want the teeth to have whether for a rip or crosscut.

[AndyM]

Marv,

If, in addition, the teeth are uneven, do you try to move them as much as the flat allows each time or a little bit at a time? Any tips?

[Isaac S]

Thank you for that PSA, Marv. It's hard to emphasize too much the importance of jointing and having all of the tips of the teeth be at the same height.

[wmickley]

When you don't joint the teeth each time you file, you save time. That is why most writers recommend jointing when needed. An experienced woodworker can tell by action of the saw when jointing is needed and an experienced filer can see by looking at the wear on the teeth when jointing is helpful. The number of times one can file the saw without jointing is a measure of how skilled and consistent the filer is. If you are filing a used saw that is new to you, it makes sense to joint first. If you are filing a saw that you have maintained for decades, you can easily go 8 or 10 times without jointing.

Warren

[MarvW]

Thanks Warren, I guess I need more practice... and more experience.

BTW.... it takes me about 10 seconds to joint a saw, one that is in good condition and only needs sharpening or a touch-up. I will continue to joint before each filing.

This thread is meant for those who are new at sharpening, but thank you for your input.

[MarvW]

Hi Andy, how ya do'n?

It depends largely on how big the flat is. When reshaping and jointing a saw that is as bad as the one in the picture, the first jointings will produce fairly large flats. With those, it's not too important to get them just right, just get them as close as you can. When the teeth are all even in height, each tooth should have about the same size flat and will be small, like only about 1/32" or so. When the flats are small like that, it is easier to file off only half and the difference will be much less if you don't happen to file them exactly the same. However, I do find that I'm being mindful of having to file a little more on one side of the file versus the other side.


Another reason for jointing each time you file, is because the saw will not dull evenly. The center area of the tooth edge engages more wood than the toe end or the heel end. So to prevent the tooth edge from even beginning to become what the picture shows, it is best to spend an extra few seconds and joint each time.

[MarvW]

Hi Isaac,

I'm still working on my three jaw rake angle guide, but it's still in my head. Been getting lots of filing jobs lately. I'm still using the two adjustable rake angle guides I made when we were exchanging design ideas.

Regarding jointing each time before filing, I think of it as allowing me one more chance to get the teeth all the same size and height so that each tooth is doing it's equal share of the work.

[RonB1957]

Yikes! And I thought cows and calves were bad.

[Window Guy]

Marv ....... Thank You for this sound advise, it makes perfectly good sense to me and a practice I will follow.

Steve

[Bill_Houghton]

Kind of amazing that the previous owner didn't notice what s/he was doing and correct the problem.