How to Cut Corrugated Plastic on a CNC Router

In this video, we'll learn how to machine corrugated plastic.
Speeds and Feeds Reference:
24,000 RPM
100 Inches Per Minute Feedrate (~2500 mm/min)
Cut in One Pass
Use Tabs If Possible
Types of Cutters Tested:
1/8" Upcut - Carbide3D #102 ( shop.carbide3d... )
1/8" Downcut - Amana #46200-K ( shop.carbide3d... )
1/8" Compression - "eBay Special" (Honestly, as long as it's new and sharp, it will do fine.)
Check out our line of desktop CNC milling machines and accessories at shop.carbide3d.com

[@ARepublicIfYouCanKeepIt]

My greatest success with coroplast has been with a) vacuum hold down and b) a drag knife. A used spoilboard is the absolute worst enemy to clean cuts using any tool with materials such as coroplast and thin PVC. Surface your spoilboard, then dial in your depth of cut so as just cut through the material, but not into the spoilboard. Using these techniques, I've successfully run jobs of as many as 2,000 sheets of 4'x8' material with incredibly clean cuts requiring zero post-processing, without a single mark on the spoilboard. Hope this helps others reduce their time to success using these types of materials.

[@TheTsunamijuan]

I would think this is a good situation to try something like a spray adhesive, a fairly mild one. while still taping the corners what way you did. Super 77 might be too strong. But would be worth giving a shot. Fairly quick and easy to work with, but not sure how the plastic in this cause would behave with a solvent.

[@titanium5]

Fun series, great information! Looking forward to more videos like this, Winston!

[@guerrillasneeded]

Had to do some jobs cutting coroplast recently. It was too much mess and cleanup to work with endmills, so I tried an oscillating tangential knife, which works great - no mess or cleanup on the edges. I’m going to try a drag knife soon to see the results on that also.

[@fredkent123]

Can you please give me a link to the oscillating tangential knife? Is this something you can attach to the router?

[@Harvid.]

Straight flute end mill will probably be the better choice. because you don't need to remove any chips. No pulling or pushing in the material from the endmill.

[@ARepublicIfYouCanKeepIt]

Yup! You're definitely correct.

[@fierceflyer5]

Great info, thanks for testing for us

[@imqqmi]

I wonder if a sacrificial top and bottom layer with mild spray adhesive would yield even better results, and as others have mentioned, a straight cutter.

[@nivlacker101]

Nice. We use a cnc knife to cut in our shop. Not sure if there drag knife attachment you could try

[@vikingcat794]

there is. kzbin.info/www/bejne/n5TLmqupoZx-jqM

[@carbide3d]

There are a couple third party drag knives that will work, but you'd also need to pair it with software to compensate for the axial offset of the blade to prevent corners getting rounded off. Our Stingray drag knife wouldn't be able to cut something of this thickness. About 1/16" is it's operational max.

[@vikingcat794]

@@carbide3d drats.

[@ARepublicIfYouCanKeepIt]

@@vikingcat794 No drats. Dog River drag knife with VCarve Pro and a plug-in works flawlessly.

[@ARepublicIfYouCanKeepIt]

@@carbide3d The Dog River drag knife, together with VCarve Pro and a plug-in works flawlessly.

[@AllanScheSar]

Hello Winston :)

[@ModelingSteelinHO]

Will it cut solid 3MM or thinner Polystyrene sheet ? Building 1:87 models. This is much needed amongst scale modelers world wide. You make a affordable CNC machine for scale modelers that cuts styrene sheet. You'll be a rich man.

[@ARepublicIfYouCanKeepIt]

Yes, it will. However, a straight flute square end mill is a better choice than either downcut or compression mills. For best results, use the smallest possible diameter bit. 1/8" is probably best, though you may have no choice but to move up to 1/4" due to depth of cut for thicker materials. Set your spindle speed to 18,000 rpm or greater, then experiment with feedrates to dial in the cut quality. Also, if you don't have vacuum hold down, consider building a small vacuum table that can be affixed to your spoilboard. Alternatively, painters tape and CA clue works great. If you don't know what that is, it's when you apply painters tape to both the stock and the spoilboard, then apply CA glue to the tape on one surface, then, aligning the tape strips, press the stock onto the table. When the job completes, you simply rip the piece off the table. The painters tape is quickly and easily removed, leaving zero residue on either the piece or the table.

[@ModelingSteelinHO]

@@ARepublicIfYouCanKeepIt Thank you John.

[@kevinwelsh7490]

can you also cut Jello?

[@acerjuglans383]

You never cut plastics with a high rpm, low feed rate. It's always the other way.

[@simianwarthog]

Need a vacuum table and a drag knife. Better still, laser cut it.