Cutting metal on a scroll saw? Interesting! As I understand these saws, the drive uses a "pitman" like an ancient up-and-down sawmill. That means the velocity of the blade is not uniform throughout the stroke. (Fast in the center of the stroke and slow at the ends) A graph of the blade's velocity would be sinusoidal, like the motion if a piston on a crankshaft rotating at a constant RPM.
John,
In the
Boice-Crane catalog at owwm.com, it states that you can use all types of different blades. This saw will take blades from the size of a jeweler's blade, very very thin, to a hacksaw blade, and it says you can even mount files in it and use it as a filer. See the bottom of page 15 where it states you can cut iron, brass, copper, pewter in sheet or tubing, as well as other materials such as bone, bakelite, ivory, aluminum, die castings, as well as other materials using fret or hacksaw blades. Also notice the blade chuck next to it, it accepts any flat blade, so you can just cut a section off a blade and use it.
The seller gave me a bunch of blades, and an extra hold down he made, which is an improvement on the original which he also gave me.
What kind of scrollsaw blades are used to cut metal, and where are they purchased?
You can buy jewelers blades at Ace hardware, and OSH or HD I believe. Sold in packs of a dozen or so.
The seller showed me and gave me some narrow bandsaw blades, he told me he would just buy a band saw blade for cutting metal with fine teeth and just cut it in 9" sections. This saw holds flat ends, no pins needed, clamp it in. Since you can use 5" - 9" blades, he explained to me how to get optimal use of the blades. Only about 1 1/2" is used for the cutting stroke. Start out with 9", break an inch off and put it back in the saw. Adjust the holddown, tension it and you've got a new cutting edge. You can do that 4 times, getting essentially 5 blades out of 1.
How do you figure the correct number of strokes-per-minute to get a "correct" feet-per-minute?
Currently it has a 1725 rpm motor on it, it's got an old Dayton 1/4 HP I believe. He said if one wanted to slow it down more, you would need to change the pulleys. But he said with that motor it will cut all types of materials just fine, not to worry...he did cut bone handles for knives he made, 1/4" stainless for the blade guards to cut out the hold for it to fit over the blade, leather, copper, gold, tin, and various other stuff. If you look in the catalog linked to above, they show some files and sanding stuff being used on it, and you can use jig saw files as well which are available in a variety of sizes.
This is more than just academic interest, as I have a Craftsman scroll saw very much like the one in the photo, bought at a tag sale, sans motor, for $15.
I'm not sure if that will work on a Craftsman or not, those are intended for use with wood, as I recall. This saw has a ball bearing operated crankshaft, and as such might have more of an up/down movement than what you describe.
This is a substantially heavier machine than a Craftsman scroll saw, although those are pretty nice, I think Delta might have made those for Sears, I'm not sure.
HTH,
