Buggered saw blade ?

[Mike Holbrook]

I was interested in trying a thumb hole saw but not knowing if I would like them I was not eager to risk much just to try one. So I saw a saw with more problems than I usually bid on with 0 bids and a starting price of .99. What the heck, I placed a late max bid for $8 figuring if I got real lucky I would at least have something I could get a feel for this saw type with. Believe it or not I got it for $3.25.

Cleaned her up a little earlier tonight. It is fairly sharp and cuts quite well as is. It is a 26", 6 ppi rip. I think I will finish restoring it and keep it for construction work in the building we work from on our property. The only real problem with the saw functionally is the teeth are not properly jointed. The teeth on the toe and heel are higher by maybe 1/4". Since the problem is only in the 4-5 teeth on either end of the saw it does not hinder the way the saw cuts much.

I was thinking I would joint just the teeth on either end, rebuilding them with a lower profile, as most of the teeth seem to perform very well. If I can't get enough off the two ends in one try I am thinking I will leave them a little long until I need to sharpen the whole blade. Does this seem like a reasonable approach to you more experienced saw sharpeners?

[Jim Koepke]

My thought would be to joint it and file the whole saw again if needed. It shouldn't take all that long. I have had more than one saw with a catch point or two and a very light jointing and filing make it work smooth.

I find the first teeth sometimes the best for starting a cut. With the heal of my hand against the bottom horn the weight of saw in the cut can be finely controlled while nibbling until the full length of the saw can be pushed through the cut.

jtk

[Chris Vandiver]

Like Jim, my vote would be to joint and sharpen the whole saw.

[Mike Allen1010]

Like Jim, my vote would be to joint and sharpen the whole saw.

I agree with Chris and Jim.

A couple other benefits to consider of jointing the entire saw are:

A) Ideally you would like a "breasted" toothline, where the height of the teeth at the toe and the heel are slightly lower than the middle (the reverse of what you have now)-- sort of forming a smooth, convex line. This really aids in the smoothness and efficiency of your strokes (especially with the rip saw) due to the natural rocking motion of your arm.

B) You also may want to check how much set you currently have in the teeth, if you have too much (frequently the case with rippers), jointing and reshaping the teeth down into the saw plate is a good way to eliminate this "extra" set.

All the best, Mike

[Mike Holbrook]

I should have posted a picture to start with. I think this saw was sharpened recently. It cuts well. The only problem is someone has not been jointing it when sharpening it, or not going all the way to both ends. I don't know if you can tell in the picture but the last few teeth on both ends of the plate are a half to full tooth width taller. I am in the process of cleaning the blade, as you can see it was even nastier. I am not sure what I would accomplish by jointing all the teeth? The toe is getting a little narrow as it is. There is not much set at all in these teeth. A few of the teeth at the heel are bent which may make the set look much worse than it is.

I added a second picture with a straight edge to show the issue at the heel, same issue at the toe. Maybe people can now see that the teeth on the majority of the plate are even. I wonder how/why the toe & heel got left out of the jointing process? Maybe the saw vise just was not long enough and the sharpener was to lazy to adjust the saw position?

http://www.flickr.com/photos/16891057@N05/6925798321/in/photostream/lightbox/
http://www.flickr.com/photos/16891057@N05/6779648420/in/photostream/lightbox/ (http://www.flickr.com/photos/16891057@N05/6779648420/in/photostream/lightbox/)

[Chris Vandiver]

If you want the saw to cut optimally, you need to joint it before sharpening it. It is just part of the process. And like Mike Allen says, a breasted blade is nice(especially with a rip saw). By the way, the toe(as best I can see)is not too narrow.

[Mike Holbrook]

So which way does a breasted blade curve? Are you saying this blade is breasted, maybe intentionally?

[Chris Vandiver]

Your saw is not breasted. Breasting is a convex shape to the toothline of the blade. Your's appears to be a concave shape(typical of a saw that has been sharpened incorrectly). Breasting was and is an intentional feature of some(most)hand saws.

[Mike Holbrook]

Thats what I thought Chris, but I have not been able to find anything that explains or shows what a breasted blade is exactly, although I find lots of reference to blades being breasted. I Believe Disston use to breast their blades.

Is breasting a minor curve in the entire plate or a little curve on the toe & heel, like mine but the opposite way? I want to get the whole blade back correct/better I understand that. It just looks to me like the teeth on the two ends need to come down a fair amount and the teeth in the middle need to stay where they are. If I run a file over the teeth in the middle then it would seem I would just have to bring the teeth on the two ends down that much more? When Herman joints teeth in his video he runs the file down all teeth equally to find and raise comparatively low ones since the sharpener obviously can't just make the short ones longer. Rather than trying to find low teeth it seems I need to lower teeth on either end which are obviously too high. Maybe the suggestion is just that I wind up doing a slight total jointing so the whole blade is even or breasted?

[Chris Vandiver]

You want to joint the whole toothline, whether for a straight blade or a breasted blade. By the way, most of the saw making firms breasted their hand saw blades. The bigger the saw, the larger the breast. The breasting is along the entire length of the toothline and is a fair curve based on a very large radius. On a 28" rip saw, 3/8" proud at the center of the toothline seems about average.