Minerrichi top set cupping and splitting

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Minerrichi top set cupping and splitting

Post by kiwigeo » Fri Oct 19, 2007 5:58 pm

Ive got a Minnerichi top set that is starting to warp on me. Theres also a split propogating from one end. Whats the best way of dealing with the cupping and splitting. The set has been stickered under weights since I got it but doesnt seem to be helping.

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Post by TimS » Fri Oct 19, 2007 8:15 pm

The moitsure loss is too great

My recommendation would be to wrap the set in plastic to slow the rate of moisture loss and possible allow it to release moisture by having a small opening. If a crack has occurred you could drill a hole at the end of the crack, if it is not in the template area, and put some glue there to close the end fibres. If you have it in a humidity control room then it might be agravating the situation. I would remove it and put somewhere under shade in plastic.

Drying Tension
It might be possible that the set has a lot of tension due to the figure and grain run out etc.



regards

Tim
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Post by matthew » Fri Oct 19, 2007 10:52 pm

I find that wood behaves better when air can get all around it evenly. It will be cupping because one side is drying faster or slower than the other. Weights won't be able to stop this!

Keep the top flat and supported on battens so air can circulate freely. I think, eventually the crack will close up by itself and then you can glue it.

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Post by Allen » Sat Oct 20, 2007 7:05 am

To get air freely at the plates I have, I've strung up a makeshift clothes line and hang the wood from it. For all the plates that I've had that cupped, this has worked a treat.
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Post by matthew » Sat Oct 20, 2007 7:22 am

in fact, now I think of it, weighing it down will probably contribute to the cracking. The swelling forces that wood can exert are incredibly strong. Quarries use wooden wedges to shear off huge slabs of rock. drive them into a hole and wet with water, then wait ... BOOM!

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Post by kiwigeo » Sat Oct 20, 2007 9:16 pm

Most tonewood will move mainly across the width of the board. That being the case I dont think having a weight on top of the board is going increase the risk of splitting.

I have alot of tonewood stored in my shop and the minnerichi was fairly green when it arrived and I suspect that in the humidity controlled workshop the loss of moisture was too rapid and led to the cracking and warping.

Ive wrapped the two halves of the back in glad wrap and stickered them under light weights. Over a 12 hour period the warping appears to be less severe than it was originally. The crack unfortunately is within the template area. Worse comes to worse I might end up doing a 4 piece back.

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Post by matthew » Sun Oct 21, 2007 7:18 am

My new bass back was left on the bench during the week. It warped quite dramatically; the edges lifted about an inch off the bench!!

I left it hung up for a few days to see whether it would straighten out. It didn't.

yesterday I sprayed the concave surface lightly with water and wiped it down, and again hung it up. Magic. the board is now absolutely flat again!

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Post by kiwigeo » Sun Oct 21, 2007 12:03 pm

Je**s Matthew....that avatar of yours is freaking me out. Every time Ive looked at one of your posts I thought I saw the thing blink. Didnt pay it much attention till now. I sat starting at it for 5 minutes and yes indeed the thing blinks.

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Post by Kim » Sun Oct 21, 2007 5:06 pm

Martin,

Hindsight is wonderful and I am sure you understand now why green wood in a dehumidified room is not a good thing. I will add that even with wood resawn into sets, if it is green, I seal the end grain with PVC pipe glue, green or blue what ever turns you on.

I have a couple of sets of Minnerichi, and mine to was sold to me as green stock requiring seasoning out. Mine had a knot just out of pattern with a lot of reactive short grain around that area that had made the board warp. So, I cut that volatile area out of the set, I wet the boards down, not lightly, I flooded the suckers a number of times throughout a day. Then on a very flat surface I sticker stacked the lot using about 5 stickers over the length of each back plate and a sheet of 10mm glass on top with heavy what have you on top of that.

Over the next couple of weeks, I unstacked and flipped the plates relocating the stickers to prevent mold by which time the wood felt dry to the touch. Next, to weaken the force in the wood, I cleaned up the now flattened sets by running them through the drum sander and grinding them with course paper to be around 1 to 1.5 mm of desired finished thickness.

The heat generated by this process assisted in bringing the wood into perfect form, I checked the end seal, treated any existing small checks with thin CA glue, and back under the glass plate they went where they have been now for a few month. Out of interest, I pulled the sets yesterday after reading this thread earlier and they are as flat as a slow cane toad in Townsville.

I am now quietly confident that things will settle out nice but only time will tell if I have been successful. I would not however be prepared to use this wood for AT LEAST another 12 month and more like a couple of years even though it has been dimensioned down so close to finish. I say this because I think that it still need to go through as many seasonal changes as possible in order to settle completely and may be this is why the process of air drying and aging timber is know as seasoning.

This may sound like a lot of futzing about, but I hold great hopes for Minnerichi, not only does it ring with that glassy ping, it carries a long distinct bassey overtone that sustains beautifully, and lets face it, it's no slouch in the looks department either. So my thinking is that as Minnerichi is so rare and exceptional, it is worth every effort to persevere.

The check that you have that goes into pattern, I would simply flood with thin CA before thicknessing and live with it, after all, there is plenty of BRW and Ziricote sets around that require treating in this way and if the rarity of BRW makes these kind of fault acceptable, why not Minnerichi? You can look on Ebay anytime and see BRW for sale, you won't find another set of the stuff you have so easy.

Cheers

Kim

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Post by Allen » Sun Oct 21, 2007 5:25 pm

Kim wrote:Martin,

Out of interest, I pulled the sets yesterday after reading this thread earlier and they are as flat as a slow cane toad in Townsville.

Cheers

Kim
Stop it Kim, I can't stop giggling...I had to toss a couple of really big ones out of the house last night. They've been coming in to eat the cat food, though I guess it's better than the python people up the road had to kill last week after it tried 5 times to eat their cat.
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Post by kiwigeo » Sun Oct 21, 2007 6:24 pm

Master Kim,

Your post is most informative and much appreciated. I suspect that the Minnerichi youre talking about is the same batch as the Minnerichi Im having issues with. I have identified the climate controlled workshop as an issue with the green wood and have dealt with it accordingly. The un-named supplier of very high repute did make it clear that the wood was green when I bought the stuff but being a green(wood)horn I didnt fully comprehend the situation and merrily stacked the wood up in my workshop assuming all would be well.

Re dealing with the crack I already have a plan to go in with the CA glue but I also have a back up plan to go for a 4 piece back if that plan doesnt work.

All under control.

Cheers Martin

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Post by Kim » Sun Oct 21, 2007 6:34 pm

Jees, the last time I seen the words "Master Kim" written on anything, it was on a bottle of worming tablets me Mum got for me from the Dr when I was 8 years old :lol:

Glad to here you have it covered mate.

Cheers

Kim

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Minnerichi Images

Post by Kim » Tue Oct 23, 2007 7:40 pm

Minnerichi, these images are from one end of the same board which is the side of a dred set, sanded with 80 grit and wet with meths. The figure is quite intense over the full length, a bit of birdseye, and a lot of curl, the sap is like woven gold satin and is as hard as the rest of the board.

This is without doubt one of, if not my most favorite of all woods. If this wood was yours, I would steal it from you :twisted:

Image

Image


Image

(EDIT: Weird thing the net, in my editor, the image directly above looked about right for colour, when I look at this post the top image is a more close representation of the chocolate, the other two images show the sap colour more clearly and accurately but lack contrast and depth of the figure?)

Cheers

Kim
Last edited by Kim on Wed Oct 24, 2007 6:49 pm, edited 1 time in total.

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Post by matthew » Tue Oct 23, 2007 10:47 pm

What type of tree is Minerichi? What does it look like? And where do you find it?

Wierd name ... sounds like Billerickie Dickie's girlfrend or something ...

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Post by Kim » Wed Oct 24, 2007 6:48 pm

Matthew,

Minnerichi is yet another Acacia. It is found up near Karratha in Western Australia, the tree looks like a kind of Sheoak and your not allowed to have any because it is all mine. :twisted:

Cheers

Kim

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Post by matthew » Wed Oct 24, 2007 8:59 pm

oh them ... i have one in my backyard. boring.

;)

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