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Tiger
13th Jun 2010, 12:05 AM
I've had the odd problem with knots when doing faceplate work like plates and bowls. They either chip out or come loose altogether. If the workpiece is otherwise fine, what is the best way of dealing with them? Can you glue sawdust into the gap or is there a better solution?

Dills58
13th Jun 2010, 03:43 AM
As you may have already found out, knots that seem sound are not after a bowl or plate has been gouged. It is a tricky thing to take the turning to a point where the knot is still secure and you have almost finished gouging. I have used "black jack" to fill around a knot just before final passes. My rule of thumb is, if the knot is loose before you start, take it out before it takes you out.

Dills.

dai sensei
13th Jun 2010, 10:04 AM
I use thin CA to stabilize the knot. Then any the gaps can be filled with a filler and the choices are endless - thick CA for clear, or coloured finish using thin CA with powders such as sawdust/charcoal/brass/copper/aluminium/malachite/torquoise etc etc

Tiger
13th Jun 2010, 10:34 AM
As you may have already found out, knots that seem sound are not after a bowl or plate has been gouged.

Dills.

You're correct, I'd never use timber with a loose knot in it. The knot seems sound and then once you're committed to it because you've spent some time turning, you find out it isn't :~. Have tried sawdust filler in the past but that tends to chip out a bit as well and you end up refilling the gap, sometimes better to just throw the piece out and cut your losses.

steck
13th Jun 2010, 11:53 AM
I use thin CA to stabilize the knot. Then any the gaps can be filled with a filler and the choices are endless - thick CA for clear, or coloured finish using thin CA with powders such as sawdust/charcoal/brass/copper/aluminium/malachite/torquoise etc etc

I agree with Dai Sensai:aro-u:
I like to collect sawdust, and stuff it into the crack, then use thin ca over the top of that. It soaks in and sets hard.
It may need a touch up with CA when you get down to your finished dimensions. Easily sanded off.
I also use CA on holey burls or if I want to keep a bark inclusion.
I think that sometimes keeping the knot adds a lot of character and interest.

issatree
13th Jun 2010, 04:30 PM
Hi Tiger,
Like Steck, I collect the dust from my sanding, & store it in a container, & when I want some to use I get the "Keeper of the House's " very fine Tea Strainer & put it into my Light Plastic " Woofer ".
I use a " 750g Saxa Salt Holder ". It has a Screw type lid, & soft sides, which allows you to control the amount of dust to come out.

I use Loctite 401 Super Glue. I run it into the Crack, Then " Woof " some Dust into it & it is dry in an instant.
Very good on your cut Fingers.
Do not use this on really soft Woods, as the Glue & Dust are harder than the Wood.

To Check the Age of the Loctite, look at the base Nos. Could be D09. That would indicate that the Glue was made in April 2009. That would still be OK today.
Regards,
issatree.

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steck
13th Jun 2010, 04:38 PM
Hi Tiger,

I use a " 750g Saxa Salt Holder ".

Now thats a good idea! I have just been using plastic bags to store my sawdust.
Thanks.

joe greiner
13th Jun 2010, 09:31 PM
For voids in general, I usually use a mortar of epoxy and filler material. Here's one using key-cutting shavings as the filler: http://www.woodworkforums.com/f8/bald-cypress-vase-86510/

More often, I use ground coffee. I over-fill the void proud of the final surface, then turn and sand flush. The final surface intersects some of the filler, to produce a terrazzo-like appearance at small scale. Here's a close-up: http://www.woodworkforums.com/f8/cedar-bowl-77115/ (last picture).

Cheers,
Joe

Sturdee
14th Jun 2010, 03:22 PM
I use a " 750g Saxa Salt Holder ". It has a Screw type lid, & soft sides, which allows you to control the amount of dust to come out.


issatree.



Based on your idea I saved about 25 empty spice containers my wife was going to throw out and as I use different kinds of wood I save some sawdust for later use.

Peter.

Manuka Jock
14th Jun 2010, 10:18 PM
I use tea leaves as a filler to bulk out the CA thin glue .
For small cracks , the fine dust from teabags , for bigger ones , loose tea leaves .
Tea , being multi coloured as it were , looks more natural than a solid colour filler .
I just rub or pack the leaves in , and then drip the glue onto it , and tamp it down into place , with a teaspoon :D
Once , for a series of large bark inclusions that had opened in the drying and needed a larger aggregate , I used crushed bark .