Interesting material experiment

[Burkhardt]

I did some experiments today with strand pressed bamboo plank, since I want to use that for a new project (window shutters) and see how it machines. I have used a lot of bamboo plywood with very good success but never tried this variety which is made from shredded bamboo strands compressed with phenolic resin. These boards are solid "wood" and intended to be used for flooring, have very durable finish, are extremely dense and hard (Janka>4000) and reasonably cheap ($129 for 27 Sqft) for 5.375" wide boards, somewhat less than 5/8" thick with T&G.

Turns out, it machines nicely and holds even very small details. While the end mill left a few fuzzies, they went off with a rotary abrasive buff right away. My test board in the pictures is 7x5 inches and the smallest characters are 1/8" tall.

I had only samples of the marbled variety but it can be had evenly straw yellow, amber or dark brown as well.
I guess I will order a few boards more than I need for my project to use for small signs or relief carvings, boxes etc. in the future.





FWIW, this is not the original finish they come with (I had planed that off) but new lacquer.

[chiloquinruss]

Only issue I've ever had with manufactured lumber is the resins really eat my bits. Let us know how your experiments come out. BTW love that sampler, very cool! Russ

[Burkhardt]

Only issue I've ever had with manufactured lumber is the resins really eat my bits. Let us know how your experiments come out. BTW love that sampler, very cool! Russ

Oh yes...don't use your expensive tapered ballnose bits with that. Bamboo is already abrasive with high silica content, the resin and overall hardness does not help and the hard coating it comes with has supposedly aluminum oxide nanoparticles in it (not sure how much of that is marketing, though).

But for such jobs I use inexpensive 1/8" bits, e.g. the v-bit was a 90-degree single flute engraving bit. Super sharp and at $2 a piece I can afford a limited life.
For the relief I used a 30-degree engraving bit this time with a 0.2mm tip (that creates the visible machining lines) but would normally use a 1/8" 0.5 mm diameter tapered ballnose like this one. Obviously that works best for small and medium sized carvings.

[scottp55]

"planed the finish off"...With the CNC G?
Also curious why you didn't cut through the original finish.
How did the Profile cutout edge sand?
Are these interior shutters you'll be making?
Thank you much for posting the details Gert!
NICE little "test" piece
scott

[Burkhardt]

"planed the finish off"...With the CNC G?
Also curious why you didn't cut through the original finish.
How did the Profile cutout edge sand?

The planing was part of the experiment to see how it behaves in the planer (relatively well but better results with the drum sander). Milling through the original finish should be possible but I suspect may need a downcut or straight flute bit to avoid lifting that thick hard film from the substrate.
Sanding gives great results but removes little material because it is so super hard. Using 220 grit leaves almost polished surface and some steel wool makes it shiny. Unlike most exotic hardwoods it does not clog the abrasive with oily caking.

Are these interior shutters you'll be making?

Yes, some adjustable shutter blinds. My problem is there is a drawer cabinet in front of the window that covers about an inch of the window lower edge and I need to find a workaround for that with a very slim frame, thus preferring very rigid material.
This engineered Bamboo material is not recommended for outdoor use. While it soaks and swells less and slower than real wood, it will destroy the resin bond when it does (at least that is what I read about it).
But I guess you could make nice buttons from it Let me know if I should mail you a sample...

[scottp55]

Thanks G.
Nah, we gave away button business and second Desktop last July (I still help them out with design etc. though)
Funny, Talking to a guy just today from the Vectric forum who's looking at trial version of FingerMaker, and Vectric kept kicking off the thread(rightly so), so now talking email and forwarded it to that guy "Tailmaker"
Control computer had Version 0_92 on it, and just came in to download the latest, so Mark and I can talk apples to apples
Wonder how may versions I was behind....now I have a little more time to play and need to make an easy on/off supplementary spoilboard.
Thanks for the kind offer, but have enough exotics to keep me busy for years and really like playing with solid woods
scott

[Burkhardt]

Now I started actually working on the shutters. The material is from CaliBamboo.com but ordered through Lowes for local pickup.

I spent a a Saturday morning drum sanding off that finish again on 27 square feet. While that factory finish looked very clean it was just too perfect and plasticky for me.
Then the afternoon and evening ripping the boards to 2 1/4" slats and chamfering on the table saw and cutting to approx. length on the miter saw. Then finding a massage place to relax. I am a 62 year old office warrior and not used to bending and standing 14 hours in a row...

Anyway, I put in another 12 hours of 3-d carving the swivel and actuating dowels at the end of the pre-cut louver slats (41 slats x 7 minutes from top and 5 minutes from bottom plus swapping/flipping time), see below, lined up for shellac spray.

At some point my wife asked if it might have been easier to just buy some custom made shutters for 400 bucks or so. Maybe she is right and I am crazy.

[scottp55]

NOT crazy Gert
There's a certain satisfaction when people compliment an item in the house, and you can say "Thanks...but that was a real pain it the back to do!"
Now me....I'd spend the next week shuffling those around for the best pattern and it might sit around for months with me changing my mind.
Funny, almost looks like 2 different woods in the pics...how many shutters will this make?
Make sure and post installed pics.
scott

[Burkhardt]

Funny, almost looks like 2 different woods in the pics...how many shutters will this make? Make sure and post installed pics. scott

Well it IS a random composite of natural with amber and dark brown heat treated bamboo. Each piece is very different. And as I noticed the brownish pieces are really splintery. Highly recommended to use gloves until sanded and sealed or alternatively tweezers. All my other Bamboo projects (especially my CNC machine frame) were only natural bamboo plywood and that does not have the problem.

Anyway, the window is 3' wide and 4' tall with two 18" wide shutters and I need 19 louver slats on each side. I made 3 more in case something goes wrong but actually all of that stuff is needed for just one window. The slats are designed to be 1/8" overlapping with a rabbet to reduce light coming through. Our bedroom is in the front of the house (in a curve of the street) and it ticks me off when cars drive by at night headlights beaming through the blinds. I am going to cut the frames sometimes this week.