[dichdoc]

I just got this plotter http://montana.craigslist.org/sys/832648231.html for free it supposedly works well I have yet to try it. I'd have more use for a cutter. Is this a feasible conversion? I've just started to research it. Any info and tips? Travis

[TOTALLYRC]

I have an HP plotter that I plan on trying to convert. the only real concern is, do the motors have enough power to pull the knife thru the material?

Mine is older and may or may not have more power. I have a knife assembly and I will be cutting down the housing to fit in place of a standard pen. This way I CAN USE IT AS BOTH A PLOTTER AND A CUTTER IF THE CUTTER WORKS OUT.
Hopefully there is a driver for your operating system, otherwise you can buy winline which will work on vista. Worst case, I can gut it and put in full cnc controls, and drive it with Mach3.

Best of luck.

Mike

[Kidder Design]

The main problem that I see with trying to do a conversion like this is the fact that there is no z axis on the machine.

A vinyl plotter works with the z axis to lower and raise the blade, at a given force, determined by the material to be cut.

With a traditional printer, the blade will always be in the down position.

Also, a vinyl plotter works both the x and y axis together to follow the curve of the line to be cut.

A printer uses a back and forth motion.
Even if you could get the blade to lower and raise, best case scenario would be a series of dots where the lines should be.

~Kevin

PS: Not trying to rain on anybody's parade, just relay what I know about each machine.

[TOTALLYRC]

The main problem that I see with trying to do a conversion like this is the fact that there is no z axis on the machine.

A vinyl plotter works with the z axis to lower and raise the blade, at a given force, determined by the material to be cut.

With a traditional printer, the blade will always be in the down position.

Also, a vinyl plotter works both the x and y axis together to follow the curve of the line to be cut.

A printer uses a back and forth motion.
Even if you could get the blade to lower and raise, best case scenario would be a series of dots where the lines should be.

~Kevin

PS: Not trying to rain on anybody's parade, just relay what I know about each machine.

A pen plotter like the one I have actually moves the pen up and down (Z axis), otherwise you would have to draw in continuos lines and you couldn't draw a square inside a square withut them being connected.
It also moves in the same way a a vinyl cutter, that is why it is a good canadate for the conversion. Since my brother has a vinyl cutter, I can say that they work in the same way except one has a pen and one has a knife.
Not trying to rain on anybodies parade.

[Kidder Design]

I was not aware that you were referring to a pen plotter.

I don't see why you could not convert it, other that being able to adjust the down force on the blade.

And with the pen being a replaceable part, you may be able to find a cutter of the same size.

I say give it a try!

If the blade cuts too deep, just raise it up a bit.

[TOTALLYRC]

I was not aware that you were referring to a pen plotter.

I don't see why you could not convert it, other that being able to adjust the down force on the blade.

And with the pen being a replaceable part, you may be able to find a cutter of the same size.

I say give it a try!

If the blade cuts too deep, just raise it up a bit.

On my plotter, I found a knife holder that is slightly lager than my pen and I just have to turn it down a little bit. My plotter also has a setting for pen force, so hopefully it will help.

Thanks for the interest.
Mike

[Kidder Design]

If it helps you any, a standard plotter runs anywhere between 50-80grams of force.
80 being the more accurate for most.

[TOTALLYRC]

If it helps you any, a standard plotter runs anywhere between 50-80grams of force.
80 being the more accurate for most.

Thanks

[bisjoe]

There are other issues.

One is the cutting bed below the carriage bar on a vinyl plotter, that provide the correct surface for the knife to penetrate the vinyl without poking through the backing. It has to be softer than metal or hard plastic as found on most pen plotters.

The other thing is the difference in the way it handles lines where they meet at various angles. You may find that a pen plotter doesn't meet enough to make vinyl weed properly at the corners.

Look at the output from a vinyl cutting plotter that has a pen on it, with the job sent as a knife job rather than a pen job, using a magnifying glass, and you will notice a slight "overcut" at the corners.

Finally, your pen plotter may not have provisions for adjusting the force and speed for different materials (calendered vs cast vs reflective)

[rcpilot82]

where are you guys finding the knives for these conversions? I have 2 pen plotters and would like to make one cut instead of plot.

[CalG]

The internet is a field full of offerings for cutter holders and knives. Ebay too.
Search "cutting/plotter" or "vinyl cutter" and dive in. For HP plotters, Mimaki knife holders fit. Sometimes the plotter mounting needs to be ruggedized for cutting applications. Rubberbands or tyewraps ;-)

The plotting software can go a long way towards making the plotting easy to weed, and the cuts square into corners. The term is "offset". As the knives swivel in thier holders in order to align with the cutting direction , the actual cut line lags the "pen" position. Different angle knives have differing amounts of "trail". or offset.
Entering a suitable "offset" value gets everything to work out.

SignBlazer. SignGo, Are free or inexpensive ways to get the application to help out.

HP 75xx pen plotters offer pen forces between 10 and 80grams, and pen speeds down to a few cm/sec. The speed is fine, but some materials need a bit of weight added to the blade holder. I've turned up a "weighted" brass knife holder body to meet those needs.

Conversion of pen plotters is a good thing! Raster style "inkjet plotters have no use once past their service lifetime;-)

[rcpilot82]

Thanks for the input. other than changing out the pen for a knife, and the software switch, is there anything else I need to do to be able to but vinyl?

[CalG]

As Bisjoe mentioned above, The support strip under the knife. You can purchase self adhesive teflon strips, or use some thick and string plastic tape. Pen plotters have a "hollow" to cushion the point impact when the pen comes down A cutter wants the material solidly supported. Plus, even though you are not supposed to cut through the vinyl, sometimes stuff happens.

Working with speed and pressure will be a trial and error thing based on your machine and the actual material you are cutting. Cut and see!
Getting comfortable with the software has it's own learning curve, I'm still on it.

[rcpilot82]

excellent, thanks for the advice! i think i'll give it a go.

[rabbitlaser]

nice for the helpful information.

[rcpilot82]

ok, my pen plotter is a Calcomp DesignMate. does anyone know what type of knives I should get for it?

[CalG]

Here is a link to a calcomp cutter knife holder. Calcomp and Graftek are the same company now, but the older units are dissimilar.

It seems(from the image shown) that the calcomp configuration is "special" or at least "different".

http://www.compath.de/procutz_445eng.html

an even better reference
http://www.cuki-messerhalter.com/eng...omp/index.html

[rcpilot82]

thanks for the links, the holders look like my pens. I have a model 3036 (36" wide media)
I see they are all overseas companys. is there any us distributors for the holder?

[rcpilot82]

I now have the plotter all set up and working but I still need a holder before I can cut vinyl. anyone got any ideas? the links above are good but impossible to order from.

[rcpilot82]

OK, here is a quick sketch I made of the pens that my plotter uses. if anyone has a holder they could measure so I can see what one to get, I'd appreciate it. Obviously the Dims will vary a bit as I measured this off a plastic Numeridex pen. I have recieved no helpfull info from any of the suppliers I have contacted so far.