Carmelized Bamboo

[Richard Korte]

A friend gave me two 6’ pieces of carmelized bamboo recently.....his wife had been saving it under their bed for the past 20 years after they had a new kitchen floor installed in their home, just in case they needed to replace any damaged boards. It seems that this type of bamboo is heat treated, causing the sugars in the wood to turn brown and harden. Under a dissecting microscope (former science teacher) there are no visible joints in the boards and the pores do appear to be filled. Anyone had experience milling this type of bamboo into tapered lams for the cores in bows?   Richard

[Stagmitis]

No joints? Is it vertically laminated? A pic would help!

[Kirkll]

20-25 years ago bamboo was real popular and used a lot for flooring. Unfortunately there was a lot of it that didn’t hold up well until certain manufacturers figured out how to build higher quality stuff from Moso bamboo….. but…. the Carmel color carbonized bamboo was the best of it because it was heat treated.

The vertical grain laminated material has been used a lot by bowyers, and was just getting popular around 20 years ago. But there was a large percentage that was low quality that came apart… I know this first  hand because I was a contractor doing a lot of flooring in those days. I replaced a lot of those bamboo floors during those years that had curled up and delaminated.     

Photos are needed to help determ8ne what you have there.    Kirk   

[Stagmitis]

Kirk the color doesn’t come from heat treating- Natural bamboo begins to change color starting at 220+ F.
After the boo strip is boiled/steamed( which destroys the natural sugars and starch) then it gets glued together.  After glue-up it gets smoked which adds the color. I doubt it’s heat treated after boiling since it’s in very narrow strips or after since the glue could not withstand the temperature needed for a color change.

[Richard Korte]

Hmmmmm....just watched a few videos on how it’s made. The color comes from high heat and pressure acting on the sugars, with no dyes added.  Seems to be made of many small bundles glued together, also under high pressure, so there are no glue line joints. Kind of like a Presto Log. I’m going to mill several tapered lams from each board and give it a go! Stay tuned!   Richard

[Kirkll]

Hmmmmm....just watched a few videos on how it’s made. The color comes from high heat and pressure acting on the sugars, with no dyes added.  Seems to be made of many small bundles glued together, also under high pressure, so there are no glue line joints. Kind of like a Presto Log. I’m going to mill several tapered lams from each board and give it a go! Stay tuned!   Richard

There is a lot of different philosophy on bamboo, and the bottom line is that all bamboo is not created equally.
Depending on the manufactures exact procedures, the quality and durability can be all over the map.  It sounds like you have a woven strand material if it looks like a presto log.  If so it's only going to be as strong as the adhesive holding it together.    I wish you luck with your testing...

They do make a woven strand that is pressed together using an epoxy resin called "Fossilized" bamboo and i've been playing with that material for awhile now and its pretty impressive.... But... The mass weight is the down side. I only use it on heavy draw weight bows now.      Kirk

[garyschuler]

I used Orientated Woven strand Carbonized Bamboo flooring years ago. People said it was going to produce slow bows with hand-shock. Well I built about 10 ASL longbows from 66” to 68” and was impressed with the outcome. It would deliver a heavy arrow with authority and yes it had some hand shock but less with heavy arrows. Still got into the 180’s with 600 grain arrow *
Not sure if this is the stuff being referred to or not.

[Richard Korte]

I cut and milled the caramelized bamboo into 4 tapered (.001) lams yesterday and glued them up into a 60" bow based on the '59 Bear Kodiak. I used some old fiberglass that Fred Anderson gave me a few years ago, one black glass at .050" and one purple-brown at .040". I milled the bamboo lams to .085 at the riser fade-outs for a total stack of .260". Here's a photo of the boards...end view.

[Richard Korte]

OOPPSS>>> Wrong photo.... Lets' try this one!

[Richard Korte]

Here's one caramelized lam next to a vertical grained lam, the kind I always use...

[Kirkll]

Yup… that is a woven strand bamboo pressed together with some type of resin, and most likely cured at high temperatures. Depending on the manufacture and how it’s made, it may or may not hold up well for you…

 it’s a crap shoot… try it, test it, and share results.   Kirk

[Jeff Freeman]

Richard I've seen some like that I call it OSB bamboo has a lot of resin in it. At least the one that I had did and heavy. JF