Cutting Dibond

[jsmithconstruct]

Does anyone have any recommendations for cutting 3mm (1/8") Dibond sheets (aluminum composite)? I need a nice clean cut on both sides. Is it possible to make one pass to achieve this with a compression bit? I am also looking for speed and feed info. Thanks

[steve_g]

Jonathan

I don't think a compression bit is necessary. I always get a clean top and bottom with an up cut "O" flute. you're cutting speeds should be for the polyethylene core and not the insignificant amount of Aluminum top and bottom... Due to ramping issues around corners and all you will always have fuzzies of re-welded plastic somewhere along the perimeter sticking up like whiskers... I always run the same file twice and all is cleaned up fine. If you're quick, you can flame polish the edges if they show, be careful though, you can warp the letters. With a 1/8" single "O" flute bit, start about 1.5 IPS ramp into the cuts. Cut full depth both passes.

Steve

[knight_toolworks]

sometimes upcut will leave a ridge sometimes not. I don't usually cut it with a downcut as the shavings are work to remove. the easiest way is to use a straight bit I like to use smaller ones like 1/8" or 1/16" Never have a lift up problem parts stay in place no matter how small cleanup is easy and you get clean on both sides. you can cut it in one pass with a 2f 1/8" straight bit. I use 8k rpms and never play with it. The stuff cuts like butter and my only real issue is making sure small parts don't go flying.
I never have fuzzies unless I am pocketing out the surface and I always only cut with a single pass.

[jsmithconstruct]

Thanks for the helpful info!! To Steve Knight - do you know the specific tool number? and what speed are you running at?

[knight_toolworks]

I just get the 2f that I can find. usually amana or a no name. 8k 2ips for the 1/8" and 1.5" ips for the 1/16" I can get the 1/8" at a local woodworking store. been getting the 1/16" bits from http://www.hartlauer-bits.com/ I use them on these 4/8 stencils I cut but they work great on dibond too.
dibond is such a joy to cut compared to most plastics. With the straight bits I can cut really small letters and never have a hold down issue.

[jsmithconstruct]

Thank you for the info, this really helps out!!

[knight_toolworks]

i like O flute bits but hey are so expensive I am chicken to use a 1/8" when it costs 30.00

[joe]

come on Steve,

You're better than that. After all you've invested all this time and equipment to be throttled back by such a silly idea. Don't be a weeenie. I don't care if it cost twice that amount there are lots of us testing this equipment for years.

Now take a deep breath and shove a good bit into the collet and get going. You can't break it under any reasonable feeds and speeds.

Joe Crumley

[knight_toolworks]

come on Steve,

You're better than that. After all you've invested all this time and equipment to be throttled back by such a silly idea. Don't be a weeenie. I don't care if it cost twice that amount there are lots of us testing this equipment for years.

Now take a deep breath and shove a good bit into the collet and get going. You can't break it under any reasonable feeds and speeds.

Joe Crumley

I know but so far I have not needed one. I am holding off till I need one for cutting aluminum. it's more that I make a error and snap it off.
I would not worry about it on dibond but I can't see spending 30.00 for a bit that 12.00 will do just as good of a job and not lift the parts up.

[joe]

These bits come in both up spiral and down spiral. That probably isn't an important factor.

[steve_g]

I use an up spiral and that's why I get the occasional "whisker" standing proud of the kerf . A down spiral would re-weld the poly core chips. Steve K says he gets no Whiskers so perhaps the straight bit is the charm here!

Steve G.

[knight_toolworks]

I noticed on these one letters I cut a few fuzzies. not sure what I cut them with or if it was real dibond or the generic stuff. I did a big job cutting these text labels for these beer taps. maybe 200 per sheet I had to pocket out the letters so the black made the letters. the first sheet went well the second sheet nope. same real dibond same cutter (a new one) same everything. but the second sheet the centers of letters would pop off and the pockets had a lot of fuzz I had to clean by hand. Huge difference and so much extra work.
even a down cut is not too bad just more work popping off the shavings. less so then if you cut acrylic with a downcut.
the straight bit keeps the parts in place the sawdust is easy to remove and you can cut at a decent speed even with a 1/16" bit.

[supertigre]

I cut Dibond (and similar) for my clients and I use an Onsrud 1/8" single flute Spiral O downcut with a ramped single pass at 20K and 2"/sec. The juju is in the climb cut so the welding of the PE is on the cutoff not the part. Perfect parts every time even on parts too small to be held by the vacuum.

[knight_toolworks]

I cut Dibond (and similar) for my clients and I use an Onsrud 1/8" single flute Spiral O downcut with a ramped single pass at 20K and 2"/sec. The juju is in the climb cut so the welding of the PE is on the cutoff not the part. Perfect parts every time even on parts too small to be held by the vacuum.
that makes sense. I was wondering what a down cut o flute was used for. but it costs 3 times more then a straight bit.

[joe]

And last five times as long.

All of using these bits aren't crazy.

[knight_toolworks]

And last five times as long.

All of using these bits aren't crazy.

I cut so many things I can't never measure cut time on most of my bits. but I know I have cut lexan for 3 or 4 hours with a straight bit. so your saying 15 hours?

[supertigre]

If you are choosing tooling because it is cheap instead of what works best then you are probably paying too much for the tooling you are using. Yes the Onsrud spiral O's are expensive to purchase but at the end of the day they are some of the cheapest tooling I own.

I figure the tooling is worth the extra cost this way, a 1/8" endmill costs $8 / $10 and will last for 2 - 4 $200 jobs before giving an unacceptable cut ($2 - $5 for tooling / job) - a 1/8" Onsrud spiral O costs $24.95 and will last 10 - 15 $200 jobs before wearing to the point it no longer cuts acceptably ($1.67 - $2.50 for tooling / job). So the cost of tooling for cutting 12 jobs using cheap endmills is about $36.00 and $24.95 using spiral O's. YMMV

[knight_toolworks]

I use a tool that does a good job.I don't know if a downcut o flute will do a better job in dibond then a straight bit or a upcut. I can test a upcut 0 flute and see if the edge is better. My local source for the bits say try a straight bit before a downcut o- flute.
I cut so many different materials that it is hard to have enough perfect bits for every job. I can cut plywood foam dibond plastic aluminum sometimes all in one day. plus seldom do I cut one thing long enough to really find the life of a bit. with say a 1/4" downcut I may cut two different types of ply mdf all with one bit so I don't know how long a bit will last.