PDA

View Full Version : Wood Choice



Randy Digby
08-22-2023, 11:59 PM
I made this clock on my Speedy 100 several years ago and I want to give it a try on my MillRight Router Pro. I want to use 1/4” plywood and I will try to use a 1/16” cutter for the small slots. What wood do you suggest that would CNC and not be prone to splinter?
Thanks
506436

George Yetka
08-23-2023, 8:13 AM
Plywood will always want to splinter. Most solid wood will machine well. I would work with a compression bit in 1/4" plywood but you may want a 1/8" bit for all profile cutting. I would make sure I stick with downcut for the rest. NEW and SHARP.

John TenEyck
08-23-2023, 11:05 AM
Baltic birch plywood is your best commercial option. I would adhere it to the spoilboard with blue tape and CA glue and use a downcut end mill for the machining. Should come out very clean. If you want a different wood than birch, you could apply commercial veneer to the BB prior to machining. The edges will still be BB, of course. Or you could make your own plywood, as I do for the clocks I make. That allows me to have any species in any thickness desired.

Unless the scale is much smaller than it appears, a 1/8" endmill should be able to do the cutouts w/o an issue. If it is really small, then use a 1/8" endmill to clean out most of it and then follow that with a 1/16" to cleanup the radii in the corners.

John

Michael Burnside
08-23-2023, 2:45 PM
I've found that if it's delicate work, hard maple or quarter sawn oak/white oak is pretty good. Bloodwood is also pretty good at resisting splinters. I recently milled a "Death Star" out of Bloodwood that was 18" in diameter with all the little line details and it came out perfect, not a single splinter. That said, that wood is freak'n hard and you might need a adjust feed/speeds for deep cuts or profiles cutouts.

For details, use a steep v-bit and cutouts use a compression or down-cut as John mentions. All of which will minimize splintering. Another trick is to cover the piece with Oramask which will help keep the fibers down.

Randy Digby
08-23-2023, 6:55 PM
Thanks, George, for your reply. I have a 1/8" single flute straight cut bit I use to cut aluminum sheet...would that work on wood vs a downcut?

Randy Digby
08-23-2023, 7:00 PM
Or you could make your own plywood, as I do for the clocks I make.

What is a good source for thin (veneer) wood to make your own plywood?

Randy Digby
08-23-2023, 7:02 PM
Good info...thanks. Would love to see a pic of your "Death Star".

John TenEyck
08-23-2023, 9:23 PM
What is a good source for thin (veneer) wood to make your own plywood?

I slice my own veneer from whatever species I want. If I were buying it, I would look at Joe Woodworker and especially Certainly Wood for veneer stock. Certainly Wood sometimes has 1/16" veneer in some species, so not as many layers are needed to build up to what you need. And of course, you can use more than one species to create unique looks, like a maple core and cherry for the outer layers. Nor does every layer have to be the same thickness. As long as the layers are balanced around the core the final ply will be stable. This is how I often adjust the buildup to get the final thickness needed.

You don't absolutely need a vacuum bag to make your own veneer, but it sure makes it a lot easier. For the clock parts I make, I find that Titebond and Titebond II work really well.

John

George Yetka
08-24-2023, 8:54 AM
Thanks, George, for your reply. I have a 1/8" single flute straight cut bit I use to cut aluminum sheet...would that work on wood vs a downcut?

I would suggest a spiral downcut. straight cut bits are not ideal.

Randy Digby
08-24-2023, 11:50 AM
I would suggest a spiral downcut. straight cut bits are not ideal.
Thanks...good stuff.

Ronald Blue
08-26-2023, 4:16 PM
This is just white pine cut with a tapered ball end mill. I do lots of things in pine and fir and have very little trouble with ragged cuts. 506649