Straighten saw?

Re: link to saw straightening advise

William R. Duffield, on the Cohansey

>Update on bowed back saw blade

Straighten saw?

Sanford Levy

>Thanks for the link, William, but I am still confused. I have the same confusions the original questioner had. Do you tap the blade on the hump to "spread the steel"? Or on the inside of the curve? How does spreading the steel, whatever that is, work? And what is the small polished hammer Todd refers to? Is it a ball peen hammer? Do you hit hard or lightly? If anyone has done this? I would be interested to hear. If no one has, I will just go on and experiment! Thanks. Sanford

Re: Straighten saw?

Ted Shuck

>I have done a few and it is surprisingly easy, once you get after it. You lay the saw over your anvil so that the curve is convex side up. That is, so that the natural curve droops over the anvil. This is opposite to what I would have thought if the steel is stretched where you hit it, but it is what works.

The hammer I used is a small 2 pound sledge. You need some weight to it and if you don't hit it hard enough, you won't see any change. You don't have to whack the bejeezus out of it, but you do have to hit it solidly. This hammer had small ridges on the face and I just filed it smooth. You want a smooth, slightly rounded face so that you don't leave any dents.

You will need to hammer it over a large area to take out a gentle curvature.

I found that it took about 15 minutes on my first saw to get the hang of it, then only about 2 minutes per saw to straighten the rest of them.

Good luck,

Ted

Anvil?

Sanford Levy

>Thanks for the information. I will see if I can try it. I wonder if it can be done without an anvil. As a beginning wood worker, I shudder at the thought of giving up wood tools to spend money on an anvil! I wonder if a sheet of plate steel over bricks can work? Or is that just dumb? Maybe I will see if I can find someone with an anvil. Thanks.

Re: Anvil?

Don Thompson - South of Miami

>Harbor Freight and the like have cheap chinese anvils that horrify serious blacksmith types, but seem to be OK for we amateurs just tapping at woodworking tools. (I have one)

Re: Anvil?

Bill Houghton, Sebastopol, CA

>The impact strength of bricks is not very high -- compressive strength is good, which is probably why you thought of this approach, but you can smash them very easily.

If you find even the Horrible Fright anvil prices too steep, and have more time than money, check around to see if you can find a junkyard that takes in large castings and other such metal, and see if you can find some large object of good weight and solidity with at least one flattish face to use as an anvil. Ask the owners whether this would serve as a surface to hammer on.

Re: Anvil?

William R. Duffield, on the Cohansey

>A couple of other tricks with which you can "make do."

First, machinist's vises have a flat surface that can be used. A small one may be too small for a saw, but I use one for peening rivets.

Second, about a foot of rail, or an even shorter length, works for a makeshift anvil.

A very small curved "anvil" surface can be made from a railroad spike clamped in a machinist's vise, or a splitting wedge stuck in a stump, or the face of a sledge hammer clamped in a vise.

Re: Anvil?

Todd Hughes

>There are so many uses for a good anvil I think all shops should have one along with a small forge....Saying this if you don't have an anvil to put your saw on to straighten it I imagine you could use the top of a table saw.I use a small hammer maybe 6oz. and use light rapid hits and I don't think it would damage your table saw.A iron plate put on the dirt or sidewalk would work as well I imagine.....Todd, who has a few anvils

Safety

GolfSteve in Calgary

>My grandfather went blind in one eye when a sliver of steel broke off the piece of rail that he used as an anvil and entered his eye.

I've been told not to use railroad track as an anvil because of this problem, but a quick google search didn't bring up any corroboration.

Some hammer faces are hardened and shouldn't be stuck with other hammers to avoid chipping and splinters - I don't know if sledge hammers faces are hardened this way or not.

In any case, regardless of my uninformed input above, use eye protection!!!

Re: Safety

Don Thompson - South of Miami

>Sorry about your grandpa (although I guess is was a while ago). The eye protection recommendation is probably a good idea whenever one is using a hammer to do anything.

When young, my grandfather lost an eye to another kid using a slingshot. As you can guess, I wasn't allowed to have so much as a picture of a slingshot in the house.

Concur

Bill Houghton, Sebastopol, CA

>I was taught never never never to hammer on one hammer with another, because the faces, both hardened, can spall off bits that will seek the most tender part of your body they can find.

I am slowly learning to wear safety glasses whenever I pick up a hammer.

Re: Safety - YES!

Ted Shuck

>Very good advice!

I am of the "age" where I can't get along without reading glasses to see anything clearly within a yard of my face. I keep a pair of prescription safety glasses in the shop. If I want to see what I am working on, I have to put them on.

Even though my eyes are not what they used to be, I would not want to lose one!

Ted

Re: shrapnel?

William R. Duffield, on the Cohansey

>Thanks for the warnings, guys. Let me see if I've got this straight. Rails and sledges are too hard to use as anvils. Mauls and spikes should work, since they are designed to be hit with hammers, right?

Re: Safety

Todd Hughes

>I don't think the problim was that the anvil was made out of a railroad track but that your grandfather hit the anvil instead of the work that was on the anvil as he should have.Lord knows that I have seen tons of good quality regular anvils that had chipped edges because of people doing this and in all cases the chip had to go somwhere I guess.Actually a good anvil is harder then a railroad track. Sure don't see much danger of a sliver of metal flying off a saw that you are straightening but if you want to wear saftey glasses that is up to you.Personaly i never fooled with them while I was doing any anvil work.

My grandfather only had one eye as well.Lost it in a fight as a young man, used to say the other guy wasn't so lucky.......Todd

Anvil?

Sanford Levy

>Hm. . . would an old wood splitting maul (to split wood for a stove) work as an anvil? Also, from what some have said, it sounds like it is important to have the right hammer as well since the can be hardened and chip like an anvil can. Do I need some sort of blacksmith's hammer? I checked Harbor Freigh and they have quite a collection, from $8.00 (10 pounds)to $70.00 (55 lbs)! Maybe one of those is the way to go. I never thought of owning an anvil! Sanford

Re: Anvil?

Bill Houghton, Sebastopol, CA

>The issue is less whether a hammer has a hardened face than whether the hammer AND the thing struck both have hardened faces. Two hardened faces can cause more problems than one, because if one of the faces isn't hardened, it will "give" when the hardened face comes into contact. That's the theory anyhow.

If your anvil is not hardened (I believe the Horrible Fright anvils are cast iron, good enough for these purposes, but not, I think, hard), then it's OK for the hammer to be hardened.

Similarly, hand drilling hammers, which look like little sledge hammers with very short handles and are used for concrete work, are not hardened, because the implements they strike (star drills, concrete nails) are.

Re: Anvil?

Todd O. Cronkhite Native of Maine

>I'm thinking that hammers used by auto body repair folks should work good for flattening saws as I think they are designed specificially for spreading metal.

I bought a Horrible Fright anvil back in '98 and dented it with my first hammer blow. Might be good for light tapping, but not for any serious hammering. I gave it to a buddy to use as an anchor for his small boat,he said it worked good for that and was a great conversation starter with the girls.

Todd O.

"great conversation starter with the girls"

Bill Houghton, Sebastopol, CA

>I musta hung out with the wrong crowd in my youth. Can't think of too many of the women I pursued who'd have found the idea of an anvil as a boat anchor intriguing.

Re: Anvil?

Sanford Levy

>I wonder which anvil you had since theyhave a number at a number of prices. Sanford

Re: Straighten saw?

Roy: Vista CA

>Get yourself a copy of "Grimshaw on Saws" written by Robert Grimshaw in 1880. It's been reprinted. Has a green cover you can get em on Ebay. It explains how the saws were pounded out or tensioned by the use of a "Doghead and a Blocking hammer and anvil.

saw

Sanford Levy

>Thanks! I will look for it.