Cutting Out

[mcaruso]

Hello All ,
I am wondering if a scroll saw is an effective way of cutting out blade outlines from barstock/sheet . Can anyone give me a recommendation for or against this ?
Thanx for your help ,
Michael

[Ray Rogers]

Blade stock is usually at least 1/8th" thick - far too much for a scroll saw. Besides, the blades available for a scroll saw are not designed for metal.

If you are thinking of buying a saw, look at the Grizzly or Harbor Freight metal saws for under $200. A lot of us on a budget use those and they work very well.

Otherwise, just use a hack saw. In either case, the blade will be roughed out. Final profiling is done on a belt sander or with files if working by hand....

[Robert Sox]

Michael:

I don't use any kind of saw to 'profile' my blades. I work from cold rolled bar stock usually. I mark the blade outline on the flat stock, usually laying out several blades as a time. Then I use a fiberglass reinforced cutoff wheel (available from Sears and many other places) on a dremmel tool to cut off each piece of the barstock. I then use old 50 or 80 grit belts on the contact wheel of my beltgrinder to grind off all the metal outside the blade outline.

I have a nice beltgrinder which makes this job pretty easy. It seems like it takes less time to grind out the profile of the blade (about 5 - 10 mins) than it does to cut off the barstock. Even the curves are easy and quick after you get the hang of it. Depending on the shape of the blade, I can use an 8" wheel for the whole blade. Sometimes I need to swap out the 8" for a 1" wheel if a finger notch is in the design. Wear gloves, work it hot, and dunk it in water often. (A workrest helps tremendously in this task.)

I can average about 3 - 4 cuts per wheel on 3/16" x 1 1/4" 440C steel. So the cost works out to be about $0.30 per cut. Faster than a hacksaw and cheaper too.

This isn't something that I ever would have thought of doing. A full-time maker invited me into his shop one day and I couldn't believe it when he profiled his blades this way. It's a good use for all those old belts that are almost dead. If you already have a beltgrinder, put it to use on this job.

Hope this helps.

[Alain M-D]

I use a angle grinder with a thin stainless cutting wheel.
It is not the best because this grinder burn the steel.
Because this, I leave a good space between my patern line
and the cut (about 3/16" at 1/2", more space around the
cutting area of the blade and less on the handle). The good
point is that type of grinder are cheap and the cutting
wheel too (more cheap than Dremel cutting wheel and
last longer) After this rought profiling, I use my belt grinder
to finish the profiling close to my template line...


But this week I will buy a band saw finally!
A cheap model, but I am sure it will be very useful!



Alain M-D

[Bob Warner]

I draw my knife shape on the steel stock then cut the piece off with a cut off saw (the angle grinder above will also work as will a band saw). Then I profile the entire knife with old beltson my grinder. to within about 1/8" to 1/16". I then use newer belts to get right to the lines.

If you don't have these tools, drill holes all the way around the knife profile and cut the web between holes with a hack saw.