[Eurekatec]

Hello!

I am new to the forum and looking for some help troubleshooting routing alupanel on our shop's CNC machine; it's pretty normal to have a bit of a burr on the aluminum, but I am having issues with the plastic core cutting "fuzzy".

We normally but bigger items and when that happens we use really find sand paper to clean it up no problem, but I have been trying to do more detailed work and it will be much trickier and time consuming.

Wondering if anyone else has had a problem with this or knows what can be causing this issue. I have attached a photo of a cut I did with the rough plastic core, using Amana Tool 46471, a 3 flute ball nose 1mm diameter.

Any suggestions would be greatly appreciated! Thank you!

 

[John Smith_]

welcome to the forum - what kind of bits have you experimented with so far ?

 

[difalkner]

An O flute bit would probably cut it cleanly. I've only cut it once and used a 1/4" downcut spiral in climb cut. It cut the product fairly cleanly but not the protective film layer, that was a bit fuzzy. What I cut wasn't to that level of detail, just some larger half moon shapes but it cleaned up with a quick hit of sandpaper as you mentioned.

 

[Eurekatec]

Thanks for the quick replies! The larger bit we usually use is an O flute, Amana Tool 51408, which works great for cutting but sometimes we get that fuzzy interior plastic. For the stuff cut in the pics it is Amana Tool 46471, a 3 flute ball nose, which is recommended for cutting aluminum and plastic.

I did some more tests with different feed rates, I attached a photo, each letter has the feed rate above it nothing else was changed: I also took a screen shot of my other settings

It's really just the plastic roughness I am concerned about because it will be too hard to clean up by hand.

 

[John Smith_]

Eure - not to run you away from this forum, but, there is a sign makers site that has hundreds of members there that does this type of work daily and the material you are using is the most common. You may find some additional help there. If you get it under control, please come back and let us know your solutions.

Signs101.com: Largest Forum for Signmaking Professionals

Largest Forum for Signmaking Professionals

www.signs101.com

 

[jw2170]

Welcome to our forum, @Eurekatec .

It appears not many members use that material on a regular basis.

I agree with John to get a second opinion from a specialist forum....

This forum started for just regular router users, and CNC has crept in over the years.

 

[old55]

Welcome to the forum.

 

[DesertRatTom]

Welcome. Interesting work you're doing.

 

[difalkner]

I did some more tests with different feed rates

Again, what I cut wasn't detailed at all but I used the bit I mentioned above in Post #3 and ran it at 18k rpm, 175 ipm, one pass. I basically cut larger half moon shapes about 24" across.

 

[gwilki]

I've done a grand total of 8 cottage signs in this material so my experience does not make me anything close to an "expert". However, in my opinion, using a ball nose mill to cut out is not optimal in any material. The strength of this mill is to do model carving. Like others here, I use an upcut o-flute bit. There is pretty much no sanding involved other than some edge breaking on the aluminum. The plastic surface is smooth. I have a router on my CNC, not a spindle. I set the speed to about 11000 rpm, with a feed rate of about 80 - 100 ipm. This using a 1/8" o-flute bit. YMMV.

 

[UglySign]

@Eurekatec Look for a flat bottom engraving bit.
Antares makes alot of engraving bits as well as others out there.
For example, Antares Standard Cutter for Soft Metals
If letters are small and use that type of bit exclusively, set the step over enough to keep the bottoms smooth.
Either way ya go the aluminum edges will fray. Could always burnish it down w/ a block of Maple carefully.

Have you tried folding ACM? They have special bits for that but
you can get away w/ a reg V doing a perimeter cut of .02~.04".
You can make some neat things with it. Cabinets, boxes, wall coverings....
Like Push-Thru signs and have it backlit. ACRylic w/ flange behind
or even wood/laminate on top of ACR illuminated.

 

[TenGees]

I've never used that material. Sometimes a single cutting edge worked better than a double when I was cutting plexi (those were straight bits not spiral). The more flutes might clog easier.

 

[Eurekatec]

Eure - not to run you away from this forum, but, there is a sign makers site that has hundreds of members there that does this type of work daily and the material you are using is the most common. You may find some additional help there. If you get it under control, please come back and let us know your solutions.

Signs101.com: Largest Forum for Signmaking Professionals

Largest Forum for Signmaking Professionals

www.signs101.com

Thanks for the tip, this forum seems really great with a lot of input from the users so I will continue using it but it's nice to have somewhere else to go when it's something more specific

 

[Eurekatec]

I've done a grand total of 8 cottage signs in this material so my experience does not make me anything close to an "expert". However, in my opinion, using a ball nose mill to cut out is not optimal in any material. The strength of this mill is to do model carving. Like others here, I use an upcut o-flute bit. There is pretty much no sanding involved other than some edge breaking on the aluminum. The plastic surface is smooth. I have a router on my CNC, not a spindle. I set the speed to about 11000 rpm, with a feed rate of about 80 - 100 ipm. This using a 1/8" o-flute bit. YMMV.

Thanks, I was thinking it was the ball nose leaving those little grooves in the plastic but it was the only bit we had on hand small enough to do the letters; we are looking into some other bits to try I'll post some updates of what we experiment with and how it turns out