ctwo wrote:I tried out my new 10 TPI blade on a piece of 2 x 1/4 inch steel bar and got a square cut with a slight concave.
That's one of the negative aspects of having a saw that uses a ½" x ,025 blade. They tend to cut with a cup, and if you over feed, it gets worse. That's the only thing I don't like about my little Wells A7.
Then I tried a piece of 2" diameter aluminum bar, 1/8" slice came out within 0.010" thickness all around. The 6 TPI seems like it will work better on aluminum.
Yep, and a 4 pitch skip tooth will work all the better, assuming you're not cutting small diameter material (keep the *two teeth in the cut* rule in mind when making a blade choice.
I have six pitch blade stock and have made blades for my Wells A7. They cut great for large sized cuts, but the problem with concave cuts gets worse, as there's so little back to the blade. You get around that with a skip tooth blade, as the teeth are spaced but the gullet is widened instead of making it deeper in the blade. That provides for a little better support. Also helps if you can keep the blade well tensioned.
How do you know how much blade weight is right? I was pushing it down manually a bit, otherwise it seemed to cut too slowly.
You can rush the cut with small blades, as they respond with wonky cuts. Keep the blade well tensioned and allow the weight of the saw to make the cut. If you have a static hydraulic feed, use it to limit how fast the blade can cut. Keep an eye on the chips. If you're generating a respectable chip at the cut, you're probably doing fine. If not, investigate the reason. If you're using a blade that's too fine for the cut, the gullets load with chips and limit the blade's ability to cut. That tends to raise the temperature in the cut and wear the blade prematurely. As is almost always the case, a cutting tool that isn't generating a chip is usually being worn excessively.
Harold
