Crack happens
- Thread starter qquake
- Start date
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JohnU
Member
I've had issues with olive also. I made a bangle bracelet from and olive cutting board and had cracks appear months later even under a ca finish.
qquake
Member
egnald
Member
That stinks. I've had similar problems on occasion. I've gotten into the habit of making sure the tubes are clean and I chamfer them a bit with a chamfering tool before assembly. I also am in the habit of smearing a little bit of wax around the inside of the tube just before I press the pieces in. I don't know if it really adds the lubricity that I expect from it, but at least it makes me feel better. Olive is such a pretty wood. I hope you have better luck on the rest! - Dave
Is it possible for blanks to crack due to cooling from the heat generated during sanding/finishing? I had some very fine hairline cracks (barely visible) in two rollerball kits I made. They appeared before I even assembled, and I wasn't really sure how...I have become overly careful assembling, as the pen assembly/disassembly rig I have, which has a holed plastic stop on one end and a metal cylinder on the other, has been marring the nibs when I put them in. So I never over-crank anything, but sometimes I still notice cracks in my turned blanks. Only thing I could think is maybe heating and cooling was allowing the wood to pull apart?
Never thought of waxing the tubes. I have some of that screw wax, which is very thin and goes a long way...wonder if that would help.
qquake
Member
I think in my case, it was a matter of not cleaning the tube before I assembled. I should get into the habit of doing that, but in my defense, I rarely have pens crack.
mark james
IAP Collection, Curator
The simple answer is... YES. Heat is not your friend, and any unnecessary heat from drilling/turning/finishing/polishing should be minimized. I, try to slow down. Repeatedly clean my drill every 1/4", wipe with water if hot. And the rest of the process goes patiently while monitoring heat. Different timbers will react differently. Experience will teach you what you do not know.
1080Wayne
Member
Yes , if
Cracking is a risk any time the wood gets hot enough that you can`t comfortably hold an uncalloused finger on it . Drill as Mark suggests , with a sharp bit . On very hard crack prone woods , I flood the hole with water every 1/4 inch . Don`t worry about flat work thinking that wood and water don`t mix . The wood did grow up with it , after all .
Ah, I didn't even think about drilling. I wonder if the cracks actually happened then, and I only noticed them later. I do clear the bit flute frequently when drilling, but I wasn't paying much attention to heat. I did read (or watch) something about blanks (notably acrylic) expanding when drilling, and then contracting when cooling down, to the point where the tubes wouldn't fit. I hadn't experienced that problem, so I hadn't put much additional thought into drill heating.
I don't think I've gotten the wood hot enough that it was uncomfortably hot to my fingers while sanding. It has gotten fairly warm, maybe hotish, but not uncomfortable. I have had uncomfortably hot sandpaper when sanding bowls at too high of a speed, so I think I understand the temperature we are talking about. I have turned more acrylic/poly pens than wood at this point, I think, and I guess I'm probably a bit worried about melting such blanks!