Fibreglass

[rhfurniture]

I have a job coming up that involves cutting fibreglass faced plastic honeycomb.
Has anyone done this? Do I have to use those cutters that look like rotary rasps?
Any experience, recommendations on cutters, feed etc would be most welcome.

TIA,

R

[bleeth]

Ralph: I've only cut fiberglass with other tools than the cnc but unless it was bonded to wood I have always used a diamond blade. The stuff eats the edge right off other material.

[jerry_stanek]

I cut lots of fiberglass with carbide bits like Dave said it takes the edge off real quick.

[Brady Watson]

Onsrud 30-300 series Onsrud Composites Catalog (https://www.onsrud.com/oc/pdf/THINKComposites.pdf)

Not cheap...but nothing good ever is...

-B

[donchandler]

I have cut up to 1/2" thick solid fiberglass with a 3/8" diamond grit bit from Abrasive Technology. Worked real well.

[Brady Watson]

"fibreglass faced plastic honeycomb"

A whole different animal than solid fiberglass...

-B

[rhfurniture]

Ah Brady - I was wondering...
So what sort of an animal?
I am obviously not looking for an edge finish, just an accurat(ish) shape for lipping (then accurately shaping) and veneering for tabletop segments. I don't know how thick the fibreglass is, but wondered if it was pretty thin, and I used a continuous tab motion to spread the wear, whether my regular carbide Replacement Tip straight bits might work well enough - diamond tooling seems to start at ukpound 150 in this neck of the woods, which is a bit too scary. I would like to be able to cut at least 10 meters (30ft) before having to change the blade on the RT bit.
I am trying to work out whether to tell the customer to get it cut elsewhere of not - I'd much rather do it in house if possible.
Also wondering how toxic the dust might be as my extraction is a bit of a joke.
Any experience welcome.

R.

[jerry_stanek]

I have cut the bottom out of 32 x 32 shower bases and I can normally get 4 bases before the bit needs to be move the expose a new portion of the cutter. That is with a 2 flute 1/2 inch bit. I had to cut 700 of these bases by hand in the middle of summer. I wore a tyvek suit with a full resporater and still itched like crazy.

[rhfurniture]

Jerry,
OK, assume you had carbide bits, it sounds like I will manage. Have to sort out the extraction though.

Thanks,
R.

[jerry_stanek]

yes they were carbide.

[Brady Watson]

Ralph,
Diamond bits are worth the price. Not only do they last much longer than carbide - they also polish the edge, which makes a HUGE difference in cut quality. The honeycomb-specific tooling I linked, is meant to handle the delicate & brittle nature of honeycomb.

A few years ago I tried several coated & non-coated end mills while cutting some carbon fiber. The results were horrible...Only when I switched to diamond did I get the edge quality that this caliber of customer commanded.

The cost of the tooling is never a factor if the client is high enough in the food chain to appreciate the difference in quality. If the customer is going to do some post-finishing anyway, then you have much more leeway on the type of tooling that you choose & in turn, price.

In regards to your health...get yourself a 1.5 to 2HP dust collector. You're worth it...and protect your eyeballs.

-B