Inventables Community Forum

EVA Foam Cuts Well!

I had a random thought to try cutting EVA foam today…

I use some parts that are laser-cut from 2mm EVA sheet, then, glued together. I thought about casting them, but, figured it would be easy to test machining them first.

I grabbed a 5mm sheet, laid down some double-sided tape, chucked-up a straight, two-flute, 1/8" end mill, and, had at it. Surprisingly, it milled well using the Easel settings for PVC. The final, through-cut, though, was a bit rough. Not sure what I can do (if anything) about that long, “chip” string that is generated.

Video goodness… YouTube is stabilizing it now, so, it may be jerky still.

2 Likes

In all the videos and photos I have seen of X-carves. The tool stick out from the collet sure seems to be a lot. I do not have a X-carve yet but I do have a Tormach 770 CNC milling machine that I run lots of small end mill on. I always try and keep stick out from the collet as short as possible to keep deflection to a minimum. By doing that I can increase my feed rate and depth of cut.

Just an observation. Looks like your machine will cut that material with no problems.

Dave

1 Like

Old post, I know! I’m just starting in with my X-Carve (haven’t received it yet), but I’m VERY familiar with sculpting EVA and CLPE. It’s very analog, but I always used a Dremel, with sanding wheels, to mold and shape it. Obviously, a CNC is far superior, but I found the sanding wheels to be the key. If there is a type of bit like that, I’d love to know.

Depending on your spindle, it will take dremel type tools - grinding/sanding. I have not used the sanding wheels myself, but have used dremel grinding stones on some experiments. Public Service Announcement - wear eye protection. The dremel type bits can and do self destruct from time to time.

1 Like

I’d like to continue this conversation. I recently ran some test cuts on a piece of SeaDek. It’s 2-ply EVA foam 3mm each ply (6mm overall). I tried a 1/8th 2 flute spiral upcut end mill, a 1/32nd 6 degree tapered 2 flute upcut endmill and a 1/2in 90 degree v-bit, all at different speeds and different feeds. My best results came from the v-bit at 50 IPM and roughly 22k rpm. Speed didn’t seem to make a difference at all.

There is really no info out there about feed/speed for cutting EVA, like there is for other materials. I can look up on KING Plastics website their exact bit/feed/speed recommendations, but it seems like SeaDek and other marine flooring companies have kept this all hush hush. Maybe I’m looking in the wrong place.

The material is expensive so doing test after test is not very cost effective and was hoping to get some advice. I ordered a high speed steel straight flute foam bit to see how that works, and carbide v or shaping tools seem to work well.

I think on my next test I will ramp up my feed and slow my speed. Anyone have any experience with this product?

![IMG_5126|666x500] Roughing Pass with 1/8th endmill 30 IPM variable speed, (didnt see much difference through the range 16k-27 (upload://3vegtxotQXK6uRKz2n324qp5uBW.jpg)![IMG_5140|666x500] The foam looks more like it was tearing and not sclicing.
(upload://qsapqA1yA2MT7CSRgTiJiU0D4gb.jpg)![IMG_5138|375x500] You can see I used the 1/2 v bit to finish the mako and “D” The rest of the word Deuces (euces) was done soley with the 1/2" v-bit at 50 IPM APPROX 20k rpm. this achieved my best result
(upload://rE223N0saSX8zFm5DFxsFueRBxn.jpg)

1 Like

I just ordered my xcarve and have very very little experience with cnc… but tons with eva. This is what i bought it for.

I have found after carving and sanding that if I hit it with a heat gun quickly that it gets rid of the fuzzies.

1 Like

lol me too, i’m trying to us this machine to help cut out templates for cosplay

Hopefully my setting help a little. I will try the heat gun trick next time. I have only done one other piece of foam since this experiment. I bought a high speed steel 2 flute straight foam cutting bit and that made a big difference. Setting my cut depth so my final pass is something like .1” helped a ton as well.

I work with SeaDek on a daily basis, and can tell you that we have special cutters developed that we can only get through them to give a top finish. I can’t tell you what they look like as we signed our lives away to get them. :face_with_symbols_over_mouth: What I can say is even with these cutters we will often run duplicate toolpaths, I run the first set to climb, and edit the duplicate path to conventional. Spindle speed is 24k. Not sure how that goes with more conventional tooling, but it may help. We use a drag knife to finally cut the profile out.
Google shows a few option for router bits are supposedly designed for EVA.
Ascent Pro router with V-Carve as our software.

2 Likes

Has anyone tried using Plastazote?

I also have a Tormach. The stick out for the inventables end mills are fixed (they have a plastic collar). Remember the force of the motion system on the 770 would easily crush your hand, but you can hold the x-carve in place easily with a few fingers .deflection is way lower as the force is lower.

I have a Whiteside Router Bits 1570 Point Cutting Round Over Bit with 3/16-Inch Radius 3/8-Inch Cutting Diameter and 3/8-Inch Cutting Length that I’ve been using with my Seadek tri-color 9mm EVA foam and it’s been doing fairly well, definitely requires some cleanup work with a dremmel but I’ve been experimenting with feeds and speeds 575mm feed/ 200mm speed. I have to trick the machine into going into more detail by telling it I’m using the 1/32 inventables bit, otherwise it doesn’t go deep enough. I’m able to do it in one pass at 6mm as well. If anyone has any advice to make it cut even cleaner would be appreciated.