cutting veneer is it possible?

[knight_toolworks]

this is the thin stuff .019 and the transfer tape was not sticky enough and it would tear. I was using a 1/16" downcut endmill and tried the drag knife. I taped the back and used spray adhesive and that kept it in place but the parts are so delicate I can't see them holding up.
I think the veneer needs to be bonded to something else myself. I can see using a laser but the peices would still be extremely fragile.
http://i154.photobucket.com/albums/s266/knighttoolworks/posting/b5e99eb3.jpg

[dlcw]

Steve,

I wonder if the Widgetworks pressure foot would work on veneer. I think I remember a video they put together showing cutting veneer using it. When I get a break in the string of projects going on right now, I'm going to try my pressure foot on veneer.

[Ajcoholic]

Cutting "raw" veneers is difficult. I have done quite a bit of marquetry and veneer work, typically it requires multiple passes with a sharp knife to get through the veneer without tearing/breakage. I doubt using a drag knife is the answer... small end mill should work if you can hold it down.

Can you try a paper backed veneer? I mean, it is much easy to work with if possible as the layer of kraft paper holds the grain from splitting.

Another product available here in Canada from Richelieu Hardware Ltd., is a real wood veneer on a phenolic backer, ie, same as a HPL (laminate). It would be the easiest I would think to cut with the cnc router, especially for inlay work.

If you are stuck with using the veneers you have, what about vacuum bagging to a heavy kraft paper? Then inlay or apply the veneer/paper sandwich same as you would the raw veneer.

AJC

[tappsman]

I cut some veneer for a friend a year or so ago. The first attempts was a disaster, the veneer chipped and split. For the second try, I had him attach the veneer to some mdf using some spray on adhesive that he had. I cut it with a small router bit at fairly slow cut rate. After I gave it back to him he released the veneer using some solvent and it fit perfect.

[knight_toolworks]

I was thinking the same glue it to a substrate. I am thinking they could fiberglass it as it is the top layer of skis that have a bamboo core. This stuff is so fragile you could not handle the parts without support.

[bleeth]

Did a bunch of that for a client a while ago. I used paper back and taped the veneer down around the edges to a piece of 1/4"mdf and ran the vacuum. Did all the cutting with a 1/8" straight bit. The smallest letters were around an inch or so in height. The results were acceptable but not spectacular.

[rbarrow]

Never been able to get acceptable results on bot... but the laser will make very short work of these with beautiful results (just turn off your exhaust system or you will end up with your work being sucked outside). I also use the laser to create the pockets for the inlay...it makes it almost completely seamless.

[jTr]

Brady posted a vacuum film technique for super thin materials, including possibly veneers. This has intrigued me - haven't tried yet, but think you should really check this out considering your challenges:

http://www.talkshopbot.com/forum/showthread.php?t=11481&highlight=vacuum+film+Technique


jeff

[knight_toolworks]

I think the problem is that the veneer is less then .02 thick. I used brady's method but the transfer tape is note quite sticky enough. But this veneer is really too thin for inlay without some backer. the pieces are so fragile you can't really handle them. the 1/16" downcut bit cut it pretty well though.

[jTr]

Sorry Steve - after commenting, I realized you had participated in that thread as well!

AJ's response regarding adhering a backer material may be the best option if a laser cut is not available.

Mike Burton authored a few books on the topic, and suggested tissue paper typically used for giftwrapped clothing could still impart a significant amount of strength if you want to keep that backer as thin as possible. Also suggested: a type of glue size to condition the veneer. It not only strengthens the veneer, but lends more flexibility. More flex = less tendency to splinter and tear out. May also lend some vac-seal assistance since pores are partly blocked with the sizing slurry.

Wish I could give you a success story rather than just suggestions, but hope you have the ability to get your job out in a timely fashion.
Best of luck - we're all pullin' for ya!

Jeff

[knight_toolworks]

these are veneers for snow skis so they are a bit long for most laser guys. But even then the parts would be super fragile. I will see if the customer can fiberglass them first. It's too bad They cover the bamboo core or they could be glued right onto it then cut.

[Brady Watson]

If you are making parts with a reasonable amount of surface area, then you can easily cut it out with a BradyVac II type fixture. You need to understand the difference between a universal bleeder & one that has vacuum directly contacting the back of the material to be cut - HUGE difference.

Even with a Lighthouse setup, you could easily hold down these veneers with vacuum. Small inlay-type parts without adequate surface area, not so much...but veneer for a ski? - No problem. You are NOT going to hold it down with a conventional bleeder board/universal vacuum system. You MUST make a dedicated fixture for it where vacuum air touches the back of the material.

You know...nobody taught me this stuff...I wanted to make the money so I figured it out without any help from anywhere else...So keep that in mind and use your own desire to 'figure it out' as fuel to just do it. Git R Done! :D

-B

[knight_toolworks]

Hold down is not the issue it's the material not holding up to cutting.

[Ajcoholic]

What about putting on a sheet of that self adhesive paper, that vinyl sign makers use to transfer the cut vinyl to whatever they are applying it to?

Stick it on top of the veneer. Cut it out - then it should be able to be laminated to the core, and then peel off the transfer paper.

Worth a try... its cheap.

AJC

[Brady Watson]

Hold down is not the issue it's the material not holding up to cutting.

Crank the RPM all the way up - lighten up on chipload. If it is not holding up to cutting, it is because the material is being ripped out. Chipload is too high. Don't cut this stuff out @ 8,000.

-B

[bleeth]

Hey Brady:
Just to make sure the point gets across-sometimes making dust instead of chips is the way to go. Try spinning your bit at 18k and move a little slow. In this case you won't be burning the bit since it really isn't cutting much but you're hitting the material really gently.

[Brady Watson]

Hey Brady:
Just to make sure the point gets across-sometimes making dust instead of chips is the way to go. Try spinning your bit at 18k and move a little slow. In this case you won't be burning the bit since it really isn't cutting much but you're hitting the material really gently.

Exactly - thanks for adding clarity.

Who cares about ideal chipload if you can't run the job?

-B

[knight_toolworks]

Hey Brady:
Just to make sure the point gets across-sometimes making dust instead of chips is the way to go. Try spinning your bit at 18k and move a little slow. In this case you won't be burning the bit since it really isn't cutting much but you're hitting the material really gently.
the pic is where I did that. no tearing but the parts are just too delicate to hold up. See great minds think alike. this stuff is so fragile and it is hard to even handle without the sheet tearing. This is the same thickness they put on plywood these days.

[Brady Watson]

Then you might not have enough RPM on your HSD period. This is why I hate 300Hz spindles...I feel they dumb things down and take a lot of versatility away. You need more RPM...A 35,000 RPM laminate trimmer adapted to your Z axis will demonstrate this. Keep in mind a dentil drill can bore a hole and carve right into a light bulb without it shattering...The veneer must be Uber soft - which means you need more RPM to keep it from ripping out and detroying itself, or you need to plasticize it somehow to harden it up.

-B

[donek]

Steve,

You own the tool designed to do this already. The drag knife you purchased does a beautiful job.

http://youtu.be/csk0QrvMHwM

If you need vacuum film, I can supply it.