CNC Routing Premask for Pre-Applied Vinyl on Acrylic

[DisplayWorks S&G]

I am looking for advice on the best transfer tape and workflow setup for cutting vinyl-faced acrylic on a CNC router.

My Current Process:

1. Apply vinyl to the acrylic sheet.
2. Apply premask over the top to protect the surface and help hold the vinyl edges down.
3. Route the shapes using an O-flute bit.

The updraft from the O-flute bit and the vacuum system can aggressively catch the freshly cut vinyl edges, causing lifting or tearing.

Looking for recommendations on a premask that is strong enough to lock the edges down but leave a clean edge without pulling the vinyl off the acrylic or causing chips to get under the vinyl.

Would love to hear how you guys keep your edges perfectly crisp on the table. Thanks!

 

[Grizzly]

Can you route with the face down? Or you can use either a down cut bit or a compression bit. It has both upward and downward spirals to keep the vinyl face from lifting.

VTX-Rc5415-A (Compression) – VTXTOOLS.COM

Multielement multilayered “rainbow” coated, “Super” carbide, polished, compression (both up and down flute) router bit with a 4mm cutting edge diameter and max milling depth of 14mm. Please note that this bit requires a minimum thickness of 3mm for the compression feature to work. With stop ring...

vtxtools.com

 

[packratsigns]

What kind of acrylic are you routing ? Large or small parts?

We would dry laminate 3m vinyl on to 4 x 8 sheets of Cyro white 3/16.
No masking.
Vinyl face up.
Clean cuts everytime.
Our bits were Belin 13476 , now known as

Onsrud 63-310 .​

Cutting speed 150-200 ipm at 16000 rpm.

Material is held down by regen vacuum on ultralight mdf

 

[JBurton]

We would dry laminate 3m vinyl on to 4 x 8 sheets

This is key, and probably 3m as well. We have mounted 3m 3630 to 3/4" sheets with great success, same procedure except slower ipm and faster rpm's.
The couple of times we've applied vinyl wet, we either wait a day or more to route, or leave them in the sun to bake out the rapidtac. Using the laminator is more of a pain (especially with 3/4" clear), but faster and gives the best result. Masking is just another layer to gum up the bit.
Also, directionality matters. On a fresh cut, do a 3" straight cut, make note of the left/right hand side for a superior edge.

 

[GaSouthpaw]

Routing with a straight flute bit (like the Onsrud 61-000 series) will give you the result you're looking for. I've run plastic with vinyl applied using the 61-061 many, many times over my time. It always works just fine unless the operator screws up.

Not to dispute packrat, but- sooner or later- an upcut bit is likely to "lift" the edges.

 

[citysignshop]

Good points all....especially waiting at least a day after dry application to allow the vinyl's adhesive to mature and bond! If it's lifting, you don't have good adhesion. A light scuff of the acrylic will not affect anything except to improve the mechanical bond! Using a roller applicator is great, but follow-up with a 'squeegee' ( plastic applicator) .....the pressure under the blade of is many times more, and will improve the bond.
I also would recommend running your basic shape with a small offset, then do a final clean-up pass to the exact contour, which should minimize lifting. Using the right bit, through some testing is also crucial. Good luck!

 

[bowtievega]

We cut quite a few push thru acrylic letters with vinyl faces on our machine. We have always used a o flute up cut bit (3/16" or 1/4" dia) for this. Down cut bits do not work well on thicker material in our experience (3/4" or 1" thick). Honestly, we don't have an issue with vinyl lifting during cutting. If the bit gets dull, you don't get a perfectly clean cut and end up with some little jagged edges where the vinyl tears a little instead of cutting clean. We leave the transfer tap on the vinyl after we install it on the acrylic as well. Helps protect the vinyl faces of the letters after they get cut out and during the install process. The transfer tape has a pretty furry edge to it from cutting but the vinyl underneath cuts clean. We have used this process for straight translucent or opaque vinyl as well as printed and laminated vinyl. Thicker the vinyl, the more issues you will have with not sharp bits.

 

[crashaffinity]

late to the game but i used to cut & heat bend pieces for a client that supplied printed vinyl to PetG. we masked the top for protection but never had lift, even with standard upcut bits. Using a straight flute should eliminate any issues, though i suspect the adhesion to the acrylic is insufficient for some reason. I've tried the same with Acrylic with no issues.

 

[Corwin Steeves]

Just did this on the weekend using half inch clear acrylic that the client wanted frosted both sides. Our supplier didn't have double sided P95 in stock so we just made our own. I premasked the top and used a sharp bit. No problems at all. But mounting the vinyl with the laminator was the key and leaving it for a day to bond also helped. If you are wet applying and then taking it straight over to the CNC, it is likely going to lift.