Twisted Wood - Arrgh..

[humbuckr]

I am trying to matchbook a piece of birdseye maple (6" x 20" x 1"). After it was cut from a longer board it has developed a slight twist and won't line up on the bandsaw to split down the middle.

any ideas - Drum sander, clamps, stand on it?

-- twisted

[wardd]

I have had some luck doing this:

If you have a drum sander, get a larger board of somekind (pine 2 x 12 works well) and sand it down flat.

Put the birdseye piece on it with blocks all the way around to keep it from moving.

I just nail the blocks into the 2 x 12, keeping them below the level of the drum of course.

Put wedges under opposing corners i.e. the high corners, so you are taking the same amount off each side.

Sand down the one side flat.

Take the birdseye piece off the board and sand the other side flat.

Split it with the band saw then keep the pieces on a flat surface with weights until you're ready to glue them.

Or, glue them up then keep the bookmatch weighted until ready to use.

I bought some of the big zip-lock bags and put my glued up tops in them to help avoid rapid changes in moisture do to humitity. And then still keep them under a pile of other lumber.

Good Luck,

d ward

[humbuckr]

thanks for the feedback and the advice that sounds as if it comes from real world experience. I will go over this and make sure I understand what you're describing and then ask a few clarifying questions.

-- cj

[wardd]

cj,

As it happens, I'm glueing up some maple pieces for a body and had to true them up with the technique I described to you.

I took some pics, they may make the procedure clearer.

Good Luck,

d ward

[ryanb]

Birdseye can be quite problematic in that respect. The previous tips are good. But after you have flattened and bandsawed your blank, it will start to twist again. Be sure to keep it weighted down and don't leave it sitting around long before you use it (i.e. glue it down onto something).

[MiKro]

What's the moisture content? if it is above 10% it needs to dry more.

Where did you get it from and is it partially air dried( check with who you purchased from)? If so It needs to sit for 3 to 6 months before you do anything with it. Yes there are tensions in wood but usually these type problems arise from wet woods. I recomend that you beg, barrow, or steal someones moisture meter and check it out. If it's betweem 6 and 8 % you are okay and it's stress in the wood, otherwise wait until it's dry.

Just my .02cents worth.

MK

[humbuckr]

I took some pics, they may make the procedure clearer.

Thanks for the pics - super helpful. I was able to get 95% of the twist out using this techinque and a 16" drum sander. my friend with the sander have never heard of this so i was grateful to teach him something in exchange.

I am a couple of weeks away from gluing the birdseye top on so I will take the advice on this thread and NOT matchbook it until I'm ready to glue it down.

thanks

-- cj

[humbuckr]

What's the moisture content? if it is above 10% it needs to dry more.

Where did you get it from and is it partially air dried( check with who you purchased from)? If so It needs to sit for 3 to 6 months before you do anything with it.

I called the store and its kiln dried and is less than 6% moisture content.

Question - Should I leave the wood in my garage since that's where I take the stuff to cut it or is it best to leave it inside my house and then haul it out there to cut?

-- cj

[wardd]

cj,

I would say to leave it in the house as the temperature and humidity will be more stable.

You should still weight it down on a flat surface.

If you have some small scraps of the same thickness you might put them above and below the piece so it still can have air circulating around it, but be held down also.

This is a good practice for any wood waiting to be used.

I would have everything ready to go when you go to bookmatch / glue the pieces.

And then a way to keep the finished top weighted down afterwards until you're ready to glue it to the body.

As MiKro said, the bookmatched piecs may want to twist once they are cut. (Cross your fingers.)

Good Luck,

d ward

[Mattia]

cj,

I would say to leave it in the house as the temperature and humidity will be more stable.

You should still weight it down on a flat surface.

If you have some small scraps of the same thickness you might put them above and below the piece so it still can have air circulating around it, but be held down also.

This is a good practice for any wood waiting to be used.

I would have everything ready to go when you go to bookmatch / glue the pieces.

And then a way to keep the finished top weighted down afterwards until you're ready to glue it to the body.

As MiKro said, the bookmatched piecs may want to twist once they are cut. (Cross your fingers.)

Good Luck,

d ward

Yep, that be good. Called stickering. Althogh you've gone a touch overkill re: the amount of stickers: I use 3 or 4 for a piece the size of a body, 4 or 5 for something the size of a guitar side/neck.

[humbuckr]