New owner means NEW EQUIPMENT! Need some advice...

[bob]

...and what in the world is tangential?...

There are two methods currently in vogue with blade cutters; drag knife and tangential. Regardless of method, in order to cut media the cutting edge of the blade must always be facing the cut. When you slice a tomato, the cutting edge of your knife faces the cut. Likewise for cutting anything else, including vinyl, with an edged instrument.

A drag knife machine's operation depends entirely on having the tip of the cutting instrument not line up with the blades rotational axis. Referred to as 'offset'. When the cut changes direction the cutting edge of the blade will always be facing the cut for no other reason than this curious off-center geometry. The 'offset' is known to the plotter and the cutting path is nudged by this distance to produce precise cuts. This system works but the fidelity of the output pretty much is dependent on having the proper offset specified and having the blade completely free to rotate via the tiny bit of leverage offered by the offset. Hence the term 'drag knife'.

A tangential machine has exactly the same requirement that the cutting edge be facing the cut path but, rather than leverage gained by geometry, the machine has a mechanism for physically rotating the blade to a;ways be facing the proper direction. Cutting square corners is relatively simple but when cutting a curve, either an actual curve or a curve simulated with some number of faces, the blade must be turned such that is is exactly tangent to the curve it's cutting at every point along its path. Hence the term 'tangential'.

A tangential cutter is generally considered superior when cutting smaller objects. Objects less than ~.75" or so. For larger objects there is very little difference in output quality between the two techniques. The drag knife machine is simpler since it lacks the blade positioning mechanism which is more expensive and is something else than can break.

Thus endeth the lesson.

 

[ATTTR]

There are two methods currently in vogue with blade cutters; drag knife and tangential. Regardless of method, in order to cut media the cutting edge of the blade must always be facing the cut. When you slice a tomato, the cutting edge of your knife faces the cut. Likewise for cutting anything else, including vinyl, with an edged instrument.

A drag knife machine's operation depends entirely on having the tip of the cutting instrument not line up with the blades rotational axis. Referred to as 'offset'. When the cut changes direction the cutting edge of the blade will always be facing the cut for no other reason than this curious off-center geometry. The 'offset' is known to the plotter and the cutting path is nudged by this distance to produce precise cuts. This system works but the fidelity of the output pretty much is dependent on having the proper offset specified and having the blade completely free to rotate via the tiny bit of leverage offered by the offset. Hence the term 'drag knife'.

A tangential machine has exactly the same requirement that the cutting edge be facing the cut path but, rather than leverage gained by geometry, the machine has a mechanism for physically rotating the blade to a;ways be facing the proper direction. Cutting square corners is relatively simple but when cutting a curve, either an actual curve or a curve simulated with some number of faces, the blade must be turned such that is is exactly tangent to the curve it's cutting at every point along its path. Hence the term 'tangential'.

A tangential cutter is generally considered superior when cutting smaller objects. Objects less than ~.75" or so. For larger objects there is very little difference in output quality between the two techniques. The drag knife machine is simpler since it lacks the blade positioning mechanism which is more expensive and is something else than can break.

Thus endeth the lesson.

Thank you for the explanation and translation!

 

[PHILJOHNSON]

Hello ATTTR,

Please feel free to give me a call at (800)527-7778, ext 112 if you have any questions regarding our different cutter models. If you would prefer email, my email address is philj@summa.us.

Best regards,

Phil Johnson
Summa Inc.

 

[Studio3Signs]

can you elaborate?

Both of them.
I own Graphtec and older HP L25500. Only thing that I would add, if you have big budget, go with Summa cutter.
I love my Graphtec, but if my budget was bigger at the time, I would have Summa cutter.

in the market now and weighing options. I hear a lot of love for Suma on this forum, but why is that exactly? specifically, what does it offer that a Graphtec FC8600 doesn't?

 

[Dennis422]

in the market now and weighing options. I hear a lot of love for Suma on this forum, but why is that exactly? specifically, what does it offer that a Graphtec FC8600 doesn't?

Not that I had any experience with Summa, but when I did my research, some of the people I talked said that they switched from Graphtec to Summa and that they liked the switch.
I guess their customer service is great, and I can tell you that a Graphtec CS has to work a lot on their response time. Few times I got the help faster from Grimco than from Graphtec.

I suppose their tracking is better, but I did quite a few 10' long print/cut designs and I did not have any issues with it. That was after I upgraded my Firmware and after I reset my cutter to the defaults after Firmware upgrade.
Now, I'm trying not to change any setting or change the Firmware because it works great.

 

[Solventinkjet]

I'm a little late but regarding JV3 parts, Mimaki is supporting the JV3-250 through September 2016 which means if you have the 4 head machine, most parts are available. The only parts you may not be able to find are machine length related parts. The heads will be available through other means for a long time to come.