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toddbron
9th March 2012, 08:18 AM
Hi,

Advice needed. I have finished a pencil holder made out of mango and then noticed a crack radiating out from the bottom in 2 directions with the major crack then going up the side of the piece. On the outside. The crack doesn't go completely through the side. I have left the piece sitting for a week to see if the crack expands and it hasn't. The tree the wood came from was cut down approx 20 years ago.

Any suggestions on whether I need to stabilise the crack and if so how do I do it?

Todd

Drillit
9th March 2012, 08:31 AM
Hello Todbron,
you could try placing it in a bucket of water with a few drops of dishwashing detergent - leave in for a couple of days and then wipe and leave to dry. Sometimes that seals it and it does work. Otherwise, if that failed you could use some of the sawdust with a CA glue (supaglue is ok). So that the glue does not leave a stain you could try rubbing the area with some lemon oil - again household quality used for cleaning - before using the CA so that it doesn leave a stain after it dries. Then sand back. Hope it works. You sure couldnt argue that the wood was green. Hope that helps, Drillit.

hughie
9th March 2012, 04:10 PM
Orange oil often will close up minor cracks other wise CA.

dr4g0nfly
10th March 2012, 05:43 AM
An answer I've seen several time in the forums (but never tried) is epoxy with coffee grounds.

Maybe someone can expand on that as I'm intrigued by it as a solution.

cookie48
10th March 2012, 12:41 PM
I have tried the coffee routine with limited success. What I am going to try nest time something cracks is vitamise the grounds to as fine as I can and try that. Might work better, as I found the normal grounds a bit coarse.

dai sensei
10th March 2012, 03:23 PM
I'd use thin CA down the crack to ensure it doesn't go any further, then fill with sawdust or similar with more thin CA to fill it.

I have used coffee grounds with thin CA for years. It is a nice dark colour and matches spalting colour usually pretty well. Old grounds are used, ie after making the coffee, then dried out in oven or dehydrator. Any moisture in the grounds will result in turning the CA white. Normal instant coffee or fresh grounds can work but may stain your work.

Hope this helps

hughie
10th March 2012, 05:06 PM
Iuse coffee grounds often with CA to fill cracks and small voids etc. It depends on the timber, below it worked well on euc burl. The dark and black marks are coffee grounds

Paul39
12th March 2012, 05:43 AM
If the crack is not structural, I will wet sand using Tung oil and 220 or finer grit. The fine dust makes a slurry and is worked into the crack. The Tung oil binds it together and the wood.

I let that dry overnight and then dry sand and finish with Tung oil applied to the rotating piece with a cloth. I keep rubbing until it begins to drag, let dry and buff with a dry cloth while the piece is still on the lathe.

For structural cracks, I wedge open the crack with a knife blade, work yellow glue into the crack, and squeeze the vessel together with a large hose clamp or clamps. If not long enough, they can be daisy chained together.

brendan stemp
12th March 2012, 08:20 PM
Perhaps prevention is better than cure. I would be interested to know if the piece of mango you were using still had the heart wood in it. Sounds to me, from what you have described, like you have used a whole section of a branch and this is will lead to this type of cracking. I could be wrong here.