Magnet cutter

[myront]

From time to time we print a small number of round magnets. By print I mean print to decal then apply to magnetic material. The magnetic material is too thick for any of our plotters to cut. We cut them all by hand. Some use scissors and some use xacto knives. I prefer the knife myself. Usually around 20 to 30 magnets. Isn't there any kind of cutter for doing circles? We tried having a machine shop make us a die but it only allows for cutting 1 size and very cumbersome to use. I've drawn a little rendition (see attached) of what I see would best suit our needs and perhaps many more out there. Any insight would be helpful. The intention would be to have it milled from aluminum and have ruler markings. All you do is line up the marks with your cut line then press the middle knob and grab the blade knob and pull it around.

 

[ChaseO]

I like where you're going with that, but how are you going to keep the center swiveling perfect and not walking and skewing your circle at all?

 

[eahicks]

https://jet.com/product/detail/d774...SvDG8GEKL6ogrKd1XDE6UT_x7QUsQNm2sLBoCc9bw_wcB

We have a smaller similar tool (we need this one) and it will leave a tiny pinhole in the center. But beats trying to hand cut them all.

 

[eahicks]

I totally dig the design you did! I would suggest one modification though...an actual handle you can turn the thing with, instead of trying to grip that blade handle.

 

[myront]

https://jet.com/product/detail/d774...SvDG8GEKL6ogrKd1XDE6UT_x7QUsQNm2sLBoCc9bw_wcB

We have a smaller similar tool (we need this one) and it will leave a tiny pinhole in the center. But beats trying to hand cut them all.

That's exactly what I didn't want when I came up with my design. A pinhole in the center would not work at all. I've seen a lot of others out there but they too use a pin as a pivet.

 

[myront]

I like where you're going with that, but how are you going to keep the center swiveling perfect and not walking and skewing your circle at all?

I believe that the center knob can be made with a very precise bearing that would be stiff enough to allow very precise cuts. Most designs can be made to include bleeds to allow for any variances. The cut line can also be made slightly larger than the desired size.

 

[myront]

If I had the know how I'd like to have a prototype produced. Any ideas who might have the capability? The "know how"

 

[fixtureman]

Why not have some templates made and use a knife to cut them

 

[myront]

Why not have some templates made and use a knife to cut them

What do you mean by templates? Like metal teplates That's pretty much the same thing we do now. Print circles and cut with a knife. Hand gets kind of tires after 30 -50 magnets.

 

[myront]

You can tell it's time for me to go home LOL
Can't type after cutting magnets all day

 

[FireSprint.com]

You could try using the olfa circle cutter from the back of the magnet (put the magnet graphic side down on your workbench) and that might limit the pinhole issue.

 

[myront]

You could try using the olfa circle cutter from the back of the magnet (put the magnet graphic side down on your workbench) and that might limit the pinhole issue.

How would you tell where the center is? You have to be able to center the cutter onto your print.

 

[player]

Put a wad of vinyl or something else on the top for the pin to stick into.

Use a template with the center marked that you can line up with the graphic to find the circle. You could
cut this template by hand.

 

[FireSprint.com]

How would you tell where the center is? You have to be able to center the cutter onto your print.

That's a good point. You could cut the graphic out to size but square and then cut from the center of the square.

Alot of overprocessing probably but it could work.

 

[woolly]

Love your sprit boys hope you find a solution but anybody that has a flat bed cutter has probably got a little smile on their face

If you know anyone that has a flat bed let them cut for you you won't believe how easy it is and accurate

 

[thewvsignguy]

my .02 is to make 4 contact points on the outside of the circle/design. Then somehow have the knife centered in those 4 contact points with an adjustable arm with the blade that will rotate. No hole in the center and the 4 contact points will proved more pressure and easier to line up.

 

[James Burke]

I'm half engineer...half tool and diemaker. I would make it with only one arm, and use a suction cup with a bearing for the center pivot. Use an x-acto blade, a swivel blade is unnecessary in this case. A simple Plexiglas template similar to a combination set center-finding square would accurately align the suction cup on center (based on the circle size).

Once aligned, simply remove the alignment template from the arm, and then cut.

Remember...you only need to score through the pvc laminate and lightly into the magnet, then bend backwards and it will snap apart cleanly. We used to cut thousands of magnets with a photo mat cutter...we'd score both directions and then snap apart all of the little pieces.

My preferred method of manufacturing would be abrasive waterjet cutting from 6061 Aluminum. This process would allow the scale and numerals to be etched, and then cut out...all in one easy setup.


JB

 

[FireSprint.com]

Love your sprit boys hope you find a solution but anybody that has a flat bed cutter has probably got a little smile on their face

If you know anyone that has a flat bed let them cut for you you won't believe how easy it is and accurate

Yessir - it's fun to think of new jigs though.

 

[myront]

I'm half engineer...half tool and diemaker. I would make it with only one arm, and use a suction cup with a bearing for the center pivot. Use an x-acto blade, a swivel blade is unnecessary in this case. A simple Plexiglas template similar to a combination set center-finding square would accurately align the suction cup on center (based on the circle size).

Once aligned, simply remove the alignment template from the arm, and then cut.

Remember...you only need to score through the pvc laminate and lightly into the magnet, then bend backwards and it will snap apart cleanly. We used to cut thousands of magnets with a photo mat cutter...we'd score both directions and then snap apart all of the little pieces.

My preferred method of manufacturing would be abrasive waterjet cutting from 6061 Aluminum. This process would allow the scale and numerals to be etched, and then cut out...all in one easy setup.


JB

This is exactly why my design above has four points to line up. There's no way with only two points. I also thought about the suction cup for the center. Might have to incorporate some sort of pads or rollers on the other points as the center would certainly raise it off the surface a bit.
Again lots of ideas but how can I actually get something produced. Should I call George's friends at InventHelp? LOL

 

[James Burke]

This is exactly why my design above has four points to line up. There's no way with only two points.

In theory, yes they can...they've been doing it for eons. In the attached photo, the two tangent points between the yellow square head, and the orange circle are the points in question. This concept works no matter the circle size. Finding the circle's center would be established by a centering rule instead of the typical scale shown.

The yellow square head shown would be what I propose to be the Plexiglas template that temporarily attaches to the cutter. No center lines would have to be drawn.

With a single arm, your manufacturing costs will be substantially more feasible, as well as your packaging/shipping costs. In my opinion, it will also be easier to use since you're going to run into issues with the other three arms possibly scuffing the material...especially as you swing larger radii.

JB