metal shear

[roger wiegand]

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I need to cut about 100 tuning sliders for organ pipes from 0.5 mm (0.02") brass in 16 different sizes differing by perhaps 0.5 mm from pipe to pipe size. The pieces will range from about an half inch to an inch wide and up to 3" long. I can't use tin snips to save my soul despite having acquired expensive ones and making many attempts over the last 60 years. The metal needs to end up flat with a straight, smooth edge. I can file a burr off. It would seem like a shear of some kind would be the right tool for this. I've seen inexpensive shears like the one pictured here and wonder if anyone has experience with them? Do you think it would work for my task? Finally, is there a better tool for the job?

Another approach I'm considering is sandwiching the brass in plywood and cutting it on the table saw, I know I can get the required accuracy and straight edges that way. I assume a carbide blade will have no issues cutting thin brass.

Thanks for your insight!

[Edward Weber]

I would make a jig/holder and cut on the bandsaw with a high tpi blade.
You could use an abrasive cut-off wheel or chop saw. I don't know what tools you have. Even a dremel with a cut off blade would work for such small diameter pieces.
Any type of shear or snips will more than likely deform the brass, requiring more handling to address the end.
Just some suggestions

[Maurice Mcmurry]

I, like Edward, suspect that shear will curl the material a tiny bit. I would want to do a test before committing to the purchase. I shared a shop with ship engineers for a few years. They used the table saw to cut brass often. Special blades are available. My engineering mentors used my regular woodworking blades, router bits too. I have followed their lead with upmost care and trepidation. A 24 TPI metal blade on the bandsaw works very well.

https://coldsawshop.com/pages/cold-s...art-calculator

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band saw cut example

[John Ziebron]

.02" brass is not that thick. Set up a jig to make 90 degree cuts and use a box blade. 2-3 scores and you should be through. Any burr can be taken care of with a very fine tooth file.

Of course, if you know someone with a laser that would be the way to go - no cleanup.

[roger wiegand]

Thanks for the ideas-- I think I will definitely hunt around for a laser that will do the trick. Offhand I don't know anyone with the appropriate machine. I've used a great online resource for other parts but they won't do metal that thin.

I will experiment with cutting it with a knife. Scoring against a straightedge has always been a somewhat error-prone process for me, I'm not sure if I can achieve the precision desired for this.

When cutting with a band saw how do you support the work? I'm imagining the thin metal bouncing up and down as the blade passes producing a rough cut, at least that's been my experience sawing thin sheet metal, hence my idea of sandwiching it in plywood for cutting.

[Maurice Mcmurry]

I had the 24 TPI on my antique 10 inch craftsman bandsaw. It runs slower than average and has a piece of formica covering the table which creates a zero clearance throat plate. I posted about the little band saw in the past but can't find the post with the pictures. I need to order a new blade and will try it on thiner brass.

https://www.grizzly.com/products/sup...aw-blade/g9172

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Don't throw out that crappy old Reliant 14" bandsaw

I will do the math on my little antique with the 24 TPI. I have not tried it on steel yet. It is running pretty slow. I have an interactive pulley calculator bookmarked that makes it easy to check...

Mine runs at 22.56 FPS. It is a very mellow cut.

[Edward Weber]

When cutting with a band saw how do you support the work? I'm imagining the thin metal bouncing up and down as the blade passes producing a rough cut, at least that's been my experience sawing thin sheet metal, hence my idea of sandwiching it in plywood for cutting.

I would get a block of wood, cut an appropriate sized slot, insert metal and cross cut. This keeps the metal captured without bouncing. A small sled or miter gauge fixture is all that's needed.

[Maurice Mcmurry]

A sled with a squeezing hold down like what Edward describes is something I would try. It could have a scale built in and a cam clamp to provide the squeeze.

[roger wiegand]

I would get a block of wood, cut an appropriate sized slot, insert metal and cross cut. This keeps the metal captured without bouncing. A small sled or miter gauge fixture is all that's needed.

Sorry, but I'm having trouble envisioning this. I can make a 20 thousandths wide slot by planing off a very shallow dado of the width required and then laminating another board onto it, but that leaves the other side of the sheet unsupported and free to move about-- now up off the saw table if I understand what you're suggesting. The brass stock I've ordered is coming in 6x12" sheets, so I'll need to make clean cuts on all four edges. I'm not getting the implication of "cross cut" in this context-- it's not like the brass has grain, and I need to cut in both the long and short dimensions.
My apologies for being dense.

[roger wiegand]

A sled with a squeezing hold down like what Edward describes is something I would try. It could have a scale built in and a cam clamp to provide the squeeze.

OK-- maybe something like a cross cut sled for a table saw that bridges the blade, with a zero clearance slot and hold-down boards on each side of the blade. I'm liking this idea! On the bandsaw it would have to be open at one end, and I'd have to back it out after each cut, but I think cutting on the table saw might also work, then I could push it all the way through. (knowing me I'd manage to cut my jig in half on the band saw.)

Hoping the brass will arrive today or tomorrow so I can try these ideas.

[Edward Weber]

Sorry if I wasn't clear enough with my description. I also didn't realize the size of the stock.
All that being said, Y think you're now seeing how you could proceed.
Good Luck

[Maurice Mcmurry]

I experimented with .090 and .004 using my small saw with a 7 1/4 inch 40 tooth thin carbide freud blade. The .090 cuts clean and easy the .004 is a mess. A combination of ideas from a crosscut sled and a coping sled are what I imagine. I will get some .020 and try a cut with that little blade. I predict it will work fine with just the miter gauge.

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[Maurice Mcmurry]

I can't find any .020 . .016 feels like it would need a backer and a caul on top for a clean cut with wood woking tools. .032 feels like it would cut just fine with just the miter gauge.

[roger wiegand]

Thank you! I'm still waiting for my stock to arrive in the mail to begin some trials. I talked to another organ builder who does use a benchtop shear. Sadly none of the laser cutting companies that I've found offer brass that thin, and I haven't yet found a makerspace or similar with an appropriate fiber laser.

[Maurice Mcmurry]

Roger, your projects are very interesting! The man I worked for in Boston is an organ builder. In 1981 his big house on Chester Square had very little on the first floor. One room contained only a grand Piano. Another room contained only his home built organ. He helped us decide if it was safe to start up the organ inside Cambridgeport church. Preserving that church was one of my father in laws projects. My wife's grandpa played the organ at Cambridgeport church for our wedding.