Small Acrylic Shapes Cut on Colex Sharpcut

[Sabernathy]

I am currently using a Colex Sharpcut to cut 3" circles, 3"x6" rectangles, etc. from 1/4" acrylic 4'x8' sheets. Sometimes I only cut into and not all the way through to make a track. I am having problems with the small pieces moving and either cutting the wrong shape or leaving a little misshapen tip where the cut starts/stops.
We have purchased a roll of double sided adhesive that should be reusable to assist with this problem.
I have tried to apply the double sided tape between coroplast and the acrylic but the thickness of the coroplast varies too much to get a consistently deep cut and the waste from the coroplast sticks to the tape. The variances in the coro were very noticeable in the tracks I cut in the acrylic because some were the .05" depth I set the cut at and some were almost 4x that depth.
I also tried 1/8" PVC 4'x8' sheets since they are much more dense and consistently measure the same thickness across the entire sheet but it's so porous the tape is more likely to stick to the Acrylic so it isn't easily reusable.

Does anyone have any suggestions for what would be a good material to use for the base of my cutting method? Just want to use something cheap, light and easily reusable even if it get's some router cuts into it.

 

[White Haus]

We've recently started using 3mm MDF for a spoil board and I'm really impressed with how well it works. Vacuum hold down is significantly higher than using the expensive cutting mats, and using sheets allows us to quickly get set up for routing and makes cleanup faster. (Using a Summa F1612) If you throw a piece of acrylic/pvc/ACM on it you won't be able to move it at all, and depending on how strong your vacuum is, it will likely help with small parts.

Another thing we'll do sometimes if routing small parts or critical panels is premask the backside of the panel, then get down position dialed in so that pieces are left in place. Our bed/routing depth isn't super consistent on our unit but if you get it dialed in just right, I'd say 95% of the pieces will be left in place and won't get bumped when the cut is completed. There is sometimes the odd spot that it will route into the MDF which may add a bit of fine dust to your parts, but with acrylic it shouldn't be an issue and might just require a quick blast with a compressor or a wipe.

Another trick I've read about here but haven't tried, is to make lead in/lead out cut paths to help with that start/stop point on the cut. This way the bit isn't starting and stopping on the part and it might reduce the odds of it getting bumped or flying out.

 

[ProColorGraphics]

We've recently started using 3mm MDF for a spoil board and I'm really impressed with how well it works. Vacuum hold down is significantly higher than using the expensive cutting mats, and using sheets allows us to quickly get set up for routing and makes cleanup faster. (Using a Summa F1612) If you throw a piece of acrylic/pvc/ACM on it you won't be able to move it at all, and depending on how strong your vacuum is, it will likely help with small parts.

Another thing we'll do sometimes if routing small parts or critical panels is premask the backside of the panel, then get down position dialed in so that pieces are left in place. Our bed/routing depth isn't super consistent on our unit but if you get it dialed in just right, I'd say 95% of the pieces will be left in place and won't get bumped when the cut is completed. There is sometimes the odd spot that it will route into the MDF which may add a bit of fine dust to your parts, but with acrylic it shouldn't be an issue and might just require a quick blast with a compressor or a wipe.

Another trick I've read about here but haven't tried, is to make lead in/lead out cut paths to help with that start/stop point on the cut. This way the bit isn't starting and stopping on the part and it might reduce the odds of it getting bumped or flying out.

you're using mdf as a spoil board on your SummaF? I thought about that, but never got around to trying it. Just have 3 different types of cutting mats. haha

 

[White Haus]

you're using mdf as a spoil board on your SummaF? I thought about that, but never got around to trying it. Just have 3 different types of cutting mats. haha

Yep! It works really well. Instead of paying $5-10 a sqft for the mat rolls, we're paying under a dollar.

One thing I did find was that when routing PVC, the mdf dust gets embedded in the edges a bit and wasn't super ideal. Otherwise acrylic, ACM etc. all routes nicely on it. Just have to dial in your down position so you're just barely scratching the surface. The amount of air that somehow stills pull through there is insane!

 

[CanuckSigns]

Yep! It works really well. Instead of paying $5-10 a sqft for the mat rolls, we're paying under a dollar.

One thing I did find was that when routing PVC, the mdf dust gets embedded in the edges a bit and wasn't super ideal. Otherwise acrylic, ACM etc. all routes nicely on it. Just have to dial in your down position so you're just barely scratching the surface. The amount of air that somehow stills pull through there is insane!

I can vouch for this, I'm using 6mm thick MDF on my f1612 and the hold down power is amazing compared to the cutting mats. We have a regular job cutting 2"x12" pieces from 3mm acm, and with the mats I was having to hold them down, with the mdf they don't move at all.

 

[MGB_LE]

Have you tried the bridge function?
https://mecsoft.com/blog/bridges-tabs-explored/ OR

Colex Cut Center 8

Colex Cut Center 8 is a modular optical recognition software system for multifunctional flatbed machines for industrial use

www.colex.com

Automatic Bridges​

Bridges prevent falling out of milled parts. Parameters such as length, distance and number can be specified individually. With manual bridges, the position can also be change

 

[Sabernathy]

We've recently started using 3mm MDF for a spoil board and I'm really impressed with how well it works. Vacuum hold down is significantly higher than using the expensive cutting mats, and using sheets allows us to quickly get set up for routing and makes cleanup faster. (Using a Summa F1612) If you throw a piece of acrylic/pvc/ACM on it you won't be able to move it at all, and depending on how strong your vacuum is, it will likely help with small parts.

Another thing we'll do sometimes if routing small parts or critical panels is premask the backside of the panel, then get down position dialed in so that pieces are left in place. Our bed/routing depth isn't super consistent on our unit but if you get it dialed in just right, I'd say 95% of the pieces will be left in place and won't get bumped when the cut is completed. There is sometimes the odd spot that it will route into the MDF which may add a bit of fine dust to your parts, but with acrylic it shouldn't be an issue and might just require a quick blast with a compressor or a wipe.

Another trick I've read about here but haven't tried, is to make lead in/lead out cut paths to help with that start/stop point on the cut. This way the bit isn't starting and stopping on the part and it might reduce the odds of it getting bumped or flying out.

That sounds like a great solution. Cheap, durable and a consistent thickness across the board is exactly what I was looking for.
I feel like you could get quite a few uses out of that one sheet too even if you had to lightly sand it every once in a while to knock the fuzz off.

 

[Ryze Signs]

I have yet to see a router that perfectly cuts small parts without them moving right at the end of the cut. If I needed to do the job you're doing I'd sub the cutting to a shop with a co2 laser.

 

[Spen101]

I used a sheet of 3/8" PVC/sintra when I needed to do this. Once we purchased a new carpet, I started just laying the old carpet on top of the new one for any routing.

What size bit are you using? For acrylic circles, I find it more of a challenge to remove the debris while running with a 1/8" tool than with anything larger. I run it at 24K rpm with something like 140 ipm, one pass, and the chips are embedded around my pieces. Handy for running small parts, I've rarely encountered many issues doing them like that. If you have to, back off your debris vacuum so it doesn't remove everything. If you get too much welding on the bit, use acetone/nail polish remover to soak it for a few minutes.

Just for the rectangles: if you're using a 3/16 or 1/4 inch tool, what I do sometimes is cut strips of matching-thickness material (3/16 or 1/4 inch acrylic or polycarb), and use these as shims. Set up your file to run lines instead of boxes, and cut all your vertical lines first (or horizontal), pause, and insert shims to fill up those gaps, then run the other direction of cuts.

 

[johnnysigns]

On our old Gerber we'd put one or two layers of thick transfer tape to the bottom side of the sheets so we could cut into that, but it wouldn't spoil the vacuum (let more and more vacuum leak as we cut more and more shapes) on the sheet.