Grain, shrinkage and stability

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Clarke

Member
Joined
25 Jul 2018
Messages
15
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Location
Essex
Hi guys, hope you can help.

I have some rough sawn, 100x50 redwood (5ths unfortunately, all I can get at the moment).
They are straight and MC of around 8%.

I am making sash windows and need to take 40x52 sections from them. Usually I would take off an equal 24mm from each side to get me from 100 to 52mm. However, all the timber has been milled from the middle of the tree (just off centre) so that the pith is roughly near the corner of each piece.

My question is, would I be better off ripping 48mm from the side nearest the pith and risk internal tension bowing the whole piece or shall I continue to take equal amounts from each side and possibly be left with some pith?
The advantage that I can see from ripping off the middle of the tree from just one edge of my timbers would be that I would be left with purely quarter sawn grain and the smallest growth rings which are currently forming flat sawn sections would be gone.

What would you do in this situation?

I can upload a photo this eve if it helps

Kindest regards

Clarke
 
I'd take ~40mm from the pith side, let it rest a week or so and then 'sneak up' to the required dimension.
Should it deform greatly in that period of time, you're better off looking for more stable stock.
 
Either way you are wasting a lot of wood - nearly half of what you've bought.
I'd go out and buy some more - if your finished size is 40 x 52 then buy 50x125. If less than twice the price of the 50 x 100 you make a saving.
 
I usually go to a proper yard but their policy is still collection only. I already have a massive stack of timbers from the last few orders that were just too twisted so decided to find the nearest place that they would actually let me sort through the pile myself. Obviously this meant very limited sizes and quality available but at least I have the straight bits.

Otherwise, yes, I'd have bought 125mm wide and ripped down the middle.

The timbers have rested for 4 days so far and only been cut to rough length, no planing yet. I'll let you all know which way I go tomorrow and whether they curl up or stay straight!
 
I usually go to a proper yard but their policy is still collection only. I already have a massive stack of timbers from the last few orders that were just too twisted so decided to find the nearest place that they would actually let me sort through the pile myself. Obviously this meant very limited sizes and quality available but at least I have the straight bits.

Otherwise, yes, I'd have bought 125mm wide and ripped down the middle.

The timbers have rested for 4 days so far and only been cut to rough length, no planing yet. I'll let you all know which way I go tomorrow and whether they curl up or stay straight!
After years of the same palaver my way around this was simply to buy by grade ("unsorted") from a yard who could supply it from the stack of known grade. Not allowing any selection from passing trade means you aren't getting the stuff they left behind. It also meant ordering by phone.
I wouldn't do it any other way for softwoods, which are well graded by the sawmills in Sweden or wherever. Hardwoods not so easy.
 
Jacob, agreed. I also understand why picking through the stack ends up with a pile of rejects by the end.
However, before corona, I have always picked myself. Also, the unsorted, joinery grade redwood fas (1sts and 2nds) can't be trusted as I find I keep 1 length in every 3-5 I pick up and check. Maybe I'm too fussy or demanding but I'm just not paying for twisted timber that's supposed to be top grade.
I can't wait till they let us roam around the timber yard freely again.
 
I think you will be fine taking it off one side, getting rid of the pith is a good thing.

I quite often use 75x100, I buy 75x225 and rip a piece off each side, I know I'm wasting 25mm but it gets rid of the pith (which there would be down the middle of a piece of 75x100 if I bought it in that size).
 
.....Also, the unsorted, joinery grade redwood fas (1sts and 2nds) can't be trusted as I find I keep 1 length in every 3-5 I pick up and check. ....
If they are letting you pick from the stack it's no longer "unsorted" and should be sold cheaper.
Basically don't go to yards where they let you pick, order by grade instead. If it's obviously under grade they usually give you a discount etc.
 
Well I went with dzj and doug71 and ended up with some lovely rift sawn stiles :D

I'll skim off the top and bottom faces tomorrow so that all 4 sides have fresh meat showing and see what happens by the weekend. The cut side from the inner is showing 2-3% higher than the outside so it should be ok.

Jacob, 'unsorted' roughly translates to 'lottery' as far as I'm concerned. Knots and defects are pretty much insignificant to me as almost everything I make is painted, it's really the straightness and how much it 'stays' straight in use that's important.

Jacob, can I also say.....it was about 15 years ago when I first started learning about sash windows. I was painting them first, then learnt how to remove them, replace ropes and balance the weights etc, progressed to splicing in repairs and then moved to making the whole thing from scratch out of rough timber. Anyway, all them years ago I spent night after night staring at this cross sectional diagram that someone had lovingly and carefully drawn (in pencil) with accurate dimensional reproductions and annotations as to the various parts and features. It was invaluable to me in seeing 'inside' the window without actually having to take it apart.
It was signed at the bottom by none other than yourself. My thanks to you, today and 15 years ago.
 
Jacob, agreed. I also understand why picking through the stack ends up with a pile of rejects by the end.
However, before corona, I have always picked myself. Also, the unsorted, joinery grade redwood fas (1sts and 2nds) can't be trusted as I find I keep 1 length in every 3-5 I pick up and check. Maybe I'm too fussy or demanding but I'm just not paying for twisted timber that's supposed to be top grade.
I can't wait till they let us roam around the timber yard freely again.

As you based in Essex, I’m surprised you don’t go to Brooks Bros - a major importer of timber.

They used to do “green split” - timber sawn to joinery section before kiln drying.

Personally I prefer to use Siberian Larch over softwood - Brooks do 25mm, 32mm, 38mm in unsorted grades 1-3. And 50mm in 1-4.
 
Hi robinbhm, brooks bros is my usual yard and have always been a fantastic place to deal with. It's just since the restrictions, the lads picking the timber just aren't as fussy as I'd like them to be. My fault.

I only recently depleted the last of my stock and was hoping they'd changed policy but not as of yet.
 
I have some wheat, but i never measured any of it when it was delivered to know if it's smaller now.
I've never seen it move though.
Hope that helps :)
 
Hairy, so long as it doesn't move after final dimensions, then it should all fit in the weetabix box nicely
 
Just to update this.....

I needn't have worried it seems. The wood behaved impeccably. I planed just enough to square it off and then left it 8 days in stick. It stayed spot on so I planed it by a few mm every other day until final dimensions, mortice and tenon, profile, glue and dryseal, bosh.

Funnily enough, it was the 6x3s that had me in circles, even though I was removing just 5mm from top and bottom and 25mm from each side, all evenly and using the same time scale as the timber above
 
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