Bamboo Woes

[staffwalker]

Fooling with Bamboo is eating my lunch. How is the heck do you guys square up the ends of a curved piece? I completed my 52th pipe this weekend and had to change the stem design from a long four knuckle bamboo to a two knuckle after trying and failing 3 or 4 times to get the ends square. Nothing worked. Chuck it up and the free end whipped around. Putting one end in the chuck and the other in a live center didn't work, the bow center whipped around. Drilling one end and inserting an oversized bit, chucking that up didn't work. I remember someone saying he tied it to a piece of wood to hold it straight while drilling. That sounds good except the bamboo I have is way to stiff to do so. Forcing the bend flat while tying it to wood did work up to the point where it cracked.

My planned 1/2 bend pipe with a long bamboo 4 knuckle stem is now a straight pipe with a shorter 2 knuckle stem.

When you complete the pipe how do you treat the bamboo stem? Wax only or something to keep out the elements such as lacquer?

bob gilbert

[Nick]

I've heard of the wood slats thing too. Also that it helps to steam the piece before using the wood slats.

[kbadkar]

Depending on how bent the bend is, this may or may not work for you. To drill, chuck up one end loosely and bring the tailstock with the right sized bit into the bamboo's capillary(?) hole so it has a little bite. Then tighten the chuck and hand spin the headstock to make sure it spins on the (capillary?) axis correctly with the tailstock end. Drill half way, flip bamboo and repeat. If the bend is too much to get it to sit in the chuck right, try only 2 jaws. You may need to fiddle a bit with the drill bit in a pin vise to get the junction of your drillings to meet up nicely... or start with a small diameter drill bit and then hand drill with the finish bit, adjusting to make ends meet. To face, chuck the drill bit on one end of the bamboo and the live center on the other. Then I face the bamboo on the drill bit end using the tip of a ground down file (using the file teeth to cut), erring on the side of concave. If it is too bent to have one end on the drill bit and the other on the live center, try just the tight fitting drill bit or pin gauge on the one end and set your lathe on the lowest RPM and hopefully the wobble won't be too bad or send your bamboo flying. Hope this helps.

[KurtHuhn]

Steaming can actually do more harm to bamboo, as the spce between the knuckles becomes software and can kink. The one method I've tried for bending bamboo that work every time is the use of a heat gun or propane torch. It does toast it slightly, but that patina adds a lot of interest.

Not that I actually suggest you take a propane torch to your bamboo or anything.

For squaring a bamboo shank:
- drill two tenons (I do this by hand)
- drill it through
- chuck your tenon bit or a pin gauge in the headstock that fits snugly
- insert the bamboo on the bit/gauge
- spin at 850-1200 RPM (my preference)
- face with a freshly sharpened 1/6" cutoff tool and take your time
- remove the bamboo and repeat for the other side

Of course, this means nothing without some sort of visual aid. I have a video of some other segments of pipe making that I've been meaning to put up, but I've lost my firewire cable for the DV Cam. As soon as the new one arrives, I'll rip and post videos of those, and then I can take a video of the bamboo process.