Cricut Cutter experiment: fail

[eeun]

I promised I'd document my testing of the Cricut Expression when it arrived.

For those who want to skip the sordid details, it's not a good styrene cutter.

Here we go:

the cutter itself

The Cricut Expression is a die cutting machine. It has a small blade attached to the moving head, and the blade free-rotates as it moves across the cutting surface. The blade depth, pressure and cutting speed can all be manually controlled. It's also possible to have the blade make multiple passes along the same cut. Seems like it'd be great for cutting styrene, right?

first test

The styrene is...I no longer have the size...about .75 mm, thick enough for making smaller structures without flexing. The plastic is taped to the cutting mat, which moves back and forth in the machine as it cuts. The mat has an adhesive to hold paper down, but the tape is extra insurance.

As you can see in the photo, the Cricut rounds corners. It also rounds straight lines.

this is straight?
The blade doesn't seem to recover quickly enough from cutting corners, possibly due to it sticking in the plastic, so short lines become curves.

What can we do about that? Not much, it seems.
I did an experiment cutting the same two shapes with varying pressures, speed, blade depth. The best result came from lightly scoring the plastic to create a channel, then repeating the cut with greater pressure multiple times.

the test

At no time, even with 8 passes over the plastic, did the Cricut actually cut through. All parts had to be 'snapped' off or cut further with an X-acto.
In the photo above, you can see the start point and end point of the cut don't even connect. Not on any of the settings.
Both these shapes were tests of replacement knee joints for Gundam kits, 1.7 cm tall for the 'H' shape, and 2.5 cm (1 inch) for the top shape. The free-rotating blade is better suited to cutting round objects. I can see the machine being useful if you were cutting out a series of round shapes, for example; building a Star Trek saucer section by contour modelling.

parts cut out

The last photo shows parts popped out of the styrene and mostly cleaned up. And clean up is the biggest issue. Due to the inaccuracy of the cuts, I found cleanup took longer than cutting the parts manually. What I would gain in time over printing to paper, transferring to plastic and manually gutting, I lost in cleanup. And with that additional shaping required to fix the parts, you lose any accuracy you'd potentially have from printing CTP (computer to plastic...a little Pre-Press humour there).

The Cricut just isn't up to the task of styrene cutting. There's laser cutting, but that's expensive for the less hard-core hobbyist. A $200 machine that could accurately cut sheet styrene would be an amazing asset to model builders, but so far, it doesn't exist.

The machine is listed on Kijiji and tentatively sold for what I paid for it (since they're much more expensive up here than I got it for on ebay), so I've not wasted my money on this experiment.

A sharp X-Acto, a steel rule, some temporary adhesive and my Chopper II are in no danger of being replaced anytime soon.

[Stu Pidasso]

You sir, are the man. Thank you so much for posting this. Excellent review.

[Rogviler]

I guess that pretty well dashes all our dreams...

I'm glad to finally know for sure though. Thanks for posting that.

-Rog

[Umi_Ryuzuki]

Some nice test cuts Ian,... good intel from those tests.

Laser cutting styrene isn't much better..

Laser cutting acrylic is awsome but the thinnest
acrylic will be 1/16" cast sheet. Good for major
parts, but not for those thin dashboard details...

The styrene looks more perforated than cut.
It almost melts itself back together, and the
sheet heat warps as it is cut.

0.010 styrene sheet tests...

http://img132.imageshack.us/img132/1596/p1010030uy.jpg

http://img34.imageshack.us/img34/3664/p1010031vg.jpg

.
.

[Johnnycrash]

Laser cutting styrene isn't much better...

Well, who ever set that up doesn't know what they are doing. Styrene cuts just fine (although acrylic is better). Either the laser is set to high, or the speed is too low. And for the perf look, it's probably the DPI that is set wrong as well (WAY too low).

Ask Disillusionist or Migmaker, they can tell you the right way to do it. It's all in the set up.

[Joseph Osborn]

eeun, can you get the Cricut deep cut blade and try again? According to the website, the deep cut blade is good for "material up to 1.5 mm thick. Use it for chipboard, wood veneer, magnet sheets, vinyl, and much more!"

It doesn't mention is the cuts will be straight, however

[Kylwell]

Matt (Disillusionist) knows all when it comes to setting to cut fine plastic.

He did some 1/20 boot tread soles for me that are phenomenal. He said they weren't cut from styrene but from something that glued fine with Tenax.

Now, anybody want to know why the Cricut makes for a lousy die cutter?

[Lt. Z0mBe]

Matt (Disillusionist) knows all when it comes to setting to cut fine plastic.

He did some 1/20 boot tread soles for me that are phenomenal. He said they weren't cut from styrene but from something that glued fine with Tenax.

Now, anybody want to know why the Cricut makes for a lousy die cutter?

Oooh! Oooh! [raises hand] I do!

Kenny

[Kylwell]

Matt (Disillusionist) knows all when it comes to setting to cut fine plastic.

He did some 1/20 boot tread soles for me that are phenomenal. He said they weren't cut from styrene but from something that glued fine with Tenax.

Now, anybody want to know why the Cricut makes for a lousy die cutter?

Oooh! Oooh! [raises hand] I do!

Kenny

Ok, it comes down to the mechanics of automated cutting. The better vinyl cutters either use a fine round bladed cutter which is offset slightly back from the pivot or a mechanically controlled pointy blade (like a no11 blade but smaller). Cheap cutters usually just use the pointy blade offset from the pivot. This means that the blade follows the head and whenever it changes direction the blade swings around the pivot and wanders off, which is why they round the corners. Now it gets even worse with the Cricut in that it's made to cut paper, stuff that may have a grain but the grain is now where near as strong as that found in styrene (and yes, styrene sheets have a grain to them). Every bit of blade that is out of the head gives the blade tip more of a chance to wander and flex. The thinner the blade the more flex you get the flex you have the more the blade will try to follow the grain (which is why the light cut followed by the subsequent cuts worked better then the single heavy cut). The next bit comes from the software and how well it's programmed to cut. Better ones break the cuts down to minimize rounding corners & what. I'm betting that the Cricut has no real programming and desperately needs a better controller for it.

That good enough Kenny?

[Kolschey]

( Claps for Kylwell's post. ) I think you've absolutely got it right there.

[eeun]

eeun, can you get the Cricut deep cut blade and try again? According to the website, the deep cut blade is good for "material up to 1.5 mm thick. Use it for chipboard, wood veneer, magnet sheets, vinyl, and much more!"

It doesn't mention is the cuts will be straight, however

It's sold already, its brief modelling career forgotten.

One of the other sites I came across trying to do this mentioned the 1.5 mm wasn't accurate, and that he couldn't get any styrene thicker than 1mm to even enter the machine.

I went through a thorough test of the deep cut blade, varying the cutter's settings and making multiple passes. Since it wouldn't cut through the .75-ish mm styrene, there was no reason to try anything thicker.

I believe the other materials mentioned will cut better because they either compress to the side as the blade pushes down and cuts, like the chipboard or cardboard; or split through when partially cut, like the magnetic sheets. Styrene doesn't do either very well by comparison.

A machine using a scribing point, rather than a blade, would probably work better. That would eliminate most of the corner rounding, too. I had the Cricut bind up on my just because it hit some of the masking tape holding down the styrene, so it's not strong enough scribing. And brand new with warranty, etc...I wasn't about to try.

[DaveVan]

Well, who ever set that up doesn't know what they are doing. Styrene cuts just fine (although acrylic is better). Either the laser is set to high, or the speed is too low. And for the perf look, it's probably the DPI that is set wrong as well (WAY too low).

I laser cut styrene plastic all the time. Set up correctly it is FANTASTIC! I can cut things on the laser that I can't cut any other way. I know this is not Sci Fi but here is a kit I offered for a while...the body was all laser cut...very little clean up.
http://www.frontiernet.net/~currtail/cashboxprod.JPG

[Lt. Z0mBe]

Matt (Disillusionist) knows all when it comes to setting to cut fine plastic.

He did some 1/20 boot tread soles for me that are phenomenal. He said they weren't cut from styrene but from something that glued fine with Tenax.

Now, anybody want to know why the Cricut makes for a lousy die cutter?

Oooh! Oooh! [raises hand] I do!

Kenny

Ok, it comes down to the mechanics of automated cutting. The better vinyl cutters either use a fine round bladed cutter which is offset slightly back from the pivot or a mechanically controlled pointy blade (like a no11 blade but smaller). Cheap cutters usually just use the pointy blade offset from the pivot. This means that the blade follows the head and whenever it changes direction the blade swings around the pivot and wanders off, which is why they round the corners. Now it gets even worse with the Cricut in that it's made to cut paper, stuff that may have a grain but the grain is now where near as strong as that found in styrene (and yes, styrene sheets have a grain to them). Every bit of blade that is out of the head gives the blade tip more of a chance to wander and flex. The thinner the blade the more flex you get the flex you have the more the blade will try to follow the grain (which is why the light cut followed by the subsequent cuts worked better then the single heavy cut). The next bit comes from the software and how well it's programmed to cut. Better ones break the cuts down to minimize rounding corners & what. I'm betting that the Cricut has no real programming and desperately needs a better controller for it.

That good enough Kenny?

Yessir. It makes perfect sense. Either round blade, stiff arm and no pivot (like machining tools) or a really, really beefy cheap pivot point with a cheap blade below it...which really wouldn't allow for much of a pivot I guess.

Excellent explanation, brother Robb.

[Kylwell]

It's been a while since I disassembled some vinyl cutters (was trying to see if I could get them working again) but the technology hasn't changed mush @ all.

I'd almost suspect that the Cricut probably doesn't have the sturdiest X/Y frame either which would only exacerbate it's other issues.

Dan & I were looking @ a large format printer & vinyl cutter @ one time. Mechanically controlled blade, super high zoot. Neato part was you could print on the vinyl then cut it out.

[DOMENECH1776]

I'm going to attempt to cut some styrene with my Silhouette SD in the next few days for my Hovertank Challenge build. I've seen examples of cut styrene from the machine and they look great. You can cut from a CAD file, and the machine cost me less than $200. Last year some online stores sold them for $125.

Note: When I say "next few days", read 1-2 weeks.

[Johnnycrash]

Note: When I say "next few days", read 1-2 weeks.

Damn you! Damn you all to hell!!!! If you ain't gonna do it NOW, why tell us about it?? Do it, THEN tell us how it went. Now, I'll be waiting and checking to see if you did do it, and how it went. Damn tease.

[Tankmodeler]

And what, pray tell, is a Silhouette SD?

Paul

[Kylwell]

http://www.silhouetteamerica.com/

[motivateon]

I am using Cricut Expression Personal Electronic Cutter 290611, it works fine for me..

[Wug]

Hi motivateon,

What are you using it for?

[eeun]

First post, and he's got a link to Cricut accessories in his tagline? I suspect he's using it for spam.

[Lt. Z0mBe]

First post, and he's got a link to Cricut accessories in his tagline? I suspect he's using it for spam.

I think you're right. Check the profile.


Kenny

[Styrofoam_Guy]

I have a Sillouette and I can cut vinyl and put an impression into thin styrene (0.010") I can then carefully flex the styrene and it will break along the scored line.

I purchased it mainly to cut vinyl. I tried the thin styrene as an experiment.

I haven't tried thicker styrene as I don't think the machine is strong enough to handle it and I don't want to break it.

[Fozzie]

I regularly cut .030" styrene with my Silhouette Cameo. It doesn't cut all the way through, of course, but it does cut it well enough that you can "flex" the piece out of the larger piece. I have found it to be incredibly useful.

[travisc]

I have a Roland Camm-1 24" vinyl cutter, that I use to cut .020 styrene.
It really does not cut it ,but scores it, I than cut out the shapes with sissors.
I draw in Autocad than using Vectric's Aspire program, to create the g code for the cutter.
I am going to build a table top CNC this winter for cutting only styrene and balsa