Help!

[Larry Gelder]

Bought a Disston DT saw yesterday. While cleaning rust off the blade with WD40 and 320 grit paper, I put a kink in the blade.

I know I should be beaten like rented mule for doing it, but how do i fix it?

[Roger Bell]

Go here to Mr Hansen's site:

http://www.norsewoodsmith.com/

Photos and discussion of how to. Lots of other good info as well.

[Leif Hanson]

Mr. Hanson :p :cool: Thanks, Mr. Bell!

Here's the relevant parts from http://www.norsewoodsmith.com/ww/sawbasics/tuningsaws1.htm:


The Black Art of Removing a Bend or Kink in a Saw


Removing a kink or a bend in a hand saw is a bit of a trick, but with patience it can be done. Two things cause bends - improper storage (something's dropped on it) or not enough set and the saw was binding in it's cut until it bent from using too much force. I didn't have a really badly bent saw to show for this, but I have one that's been poorly worked by a previous owner. Not the best candidate for showing the procedures for straightening, but perhaps it will serve:


http://www.norsewoodsmith.com/ww/sawbasics/woodrough.jpg


This is a 100 year old Woodrough & McParlin saw. It's a beautiful saw to look at, but the steel isn't all that good in it, which is why I haven't bothered straightening it before. What's wrong with the steel? Well, I personally think it's a bit soft, but really - see the photos below. Watch for the rant that's sure to come!

You'll need something that works as an anvil, with a fairly broad surface. Guess what - an anvil works best! You'll also need a hammer - a heavy, broad-faced hammer. NEVER USE A BALL PIEN HAMMER! They may work, but leave the surface of the saw horribly dented. I use a four pound sledge with a large, flat face. The term for a hammer used to flatten metal like this is a planishing hammer. Here is what results from using a ball pien hammer:

http://www.norsewoodsmith.com/ww/sawbasics/dings.jpg

Dents, dents, and more dents. Ugly... I don't know how well these photos really show it, but it is bad. There isn't anything that can be done to fix it either, I'm afraid. So I'll say it again - DON'T USE A BALL PIEN HAMMER! This is the result of a former owner's attempts to fix this saw - I'd say he did more damage than good - and the saw had made it just fine without him for 100 years before he got a hold of it. OK, I'm done with the rant...

Sighting down the saw, find the area that's bent and mark it with chalk, or layout dye, or other non-permanent marking method (no permanent ink!). The bends are almost always near dead center of the saw - if it is, place the handle of the saw on your shoulder so you can give a slight bend to the saw, resting the saw on the anvil where the bend is, with the bend facing up, like this:

http://www.norsewoodsmith.com/ww/sawbasics/hammering.jpg

The reason I bend the saw slightly isn't necessary for straightening the saw, but helps me to see where best to strike it with the hammer, using the reflection of the light to help me see the higher spots. Your fingers are another good gauge - it's amazing how minute the surface changes are that you can feel. The marks you see on the face of the blade are from the previous owner's attempt at fixing it. The bottom part of the photo shows the bend of the saw as I orient it on the anvil.

Using light blows, working the hammer directly up and down over the saw, work the area that's bent, checking the straightness of the saw often. Hammering will expand the metal on the other side from the hammer, forcing the saw straight. It can be a bit of a challenge, both in picking the right spot to hit and in not overdoing it, but it sure isn't rocket science.

This saw also had a slow bend in it, besides the kink. To fix the bend, I put the saw in the vise and work the blade gently over from the top of the bend to the bottom, (repositioning the saw in the vise as required to work the entire length of the bend):

http://www.norsewoodsmith.com/ww/sawbasics/bending.jpg

The bottom photo shows me putting more pressure on a particular spot. Be careful you don't overdo it, spend some time and bring the bend slowly to straight, checking often.

The end results aren't perfect, but do make the saw useable again:

http://www.norsewoodsmith.com/ww/sawbasics/straight.jpg

I'm not bending the saw in either photo, either - that's the best honest to god photo I could get of it's condition. I think that a good sharpening, and a re-setting of the teeth could actually straighten it out a bit more.

Never use too much force. One reason I like a heavy hammer is that I can let the hammer do it's own work, while I simply concentrate on hitting the saw metal as straight on as possible. Be careful that you do, else you will dent and damage the blade. Did I mention not to use a ball pien hammer?

HTH
Leif

Edit - it's bascally the same procedure for a back saw, though depending on how badly it is kinked it may require taking the saw apart (including removing the blade from the back if it's really bad).

[Larry Gelder]

Thanks Mr. Bell, Mr. Hansen

The saw is actually a Backsaw, not a DT saw (I was planning to cut DT with it though)

Here's a link to the style: http://www.vintagesaws.com//backsaw/b17.JPG

Confession time. I was sanding off rust without 1st removing the handle or supporting the underside of the blade. Hard to believe I was that STOOPID! :eek:

Mr. Hansen - I've reviewed your procedure, but am still getting up the nerve to perform the operation.

I don't have an anvil, but I do have a piece of railroad track. The top of the track is flat. Still a go?

I'd almost rather give this little beauty away than to further abuse her. :(

[Roy Wall]

Larry,

If you don't want to go any farther... Cook's Sharpening in PA can probably help you out.

They are very good and actually sharpen Adria saws.....and can take out the kinks....

Talk to Steve (the owner)....he'll be glad to help.

Not sure of the spelling.......may be Cooke's Sharpening....

Do a google.........

[Leif Hanson]

Mr. Hansen - I've reviewed your procedure, but am still getting up the nerve to perform the operation.

I don't have an anvil, but I do have a piece of railroad track. The top of the track is flat. Still a go?

I'd almost rather give this little beauty away than to further abuse her. :(

A piece of railroad track is perfectly fine for the task.

When you do it, just approach it cautiously (but not timidly). Check your progress often, and slowly work it to straight - don't try to get it straight on the first blow. You can do it... if you doubt yourself, get a cheapy $1 flea market saw and try it out first. Remember, also - it will need to be re-sharpened and re-set when you are finished.

If you have more questions, just ask...

I've also heard good things about Cooke's Sharpening. I don't know if linking to that site is allowed or not, so google for it, and here's their physical address (that should be post-able, I hope).

COOKE'S SHARPENING & GRINDING SERVICE INC.
3331 W. Market St. York, PA 17404
717-793-9527

Leif

[Larry Gelder]

Thanks for the encouragement and advise.

FYI - I only paid a couple buck for the saw (10", D4).

Great news. It was suggested that the blade wasn't seated in the back/spline. I measured the distance bewteen the teeth and spline and found they were different at each and of the blade (bout a hair over a 1/16th of an inch). The proposed remedy for this problem was to place the saw teeth in full contact with a piece of wood (in the sawing position) and tap the spline with a mallet, working my way along the spline.

Results. In the words of Private Gomer Pyle, SHAZAM!

The saw blade starightened out. Now, I need to sharpen it