Do you put weight on your stacks for air drying, if so what?

[Brad_bb]

I'll admit that I haven't always been diligent about putting weight on after adding boards to a stack.  I get jacket boards when milling beams so I should probably be even more diligent so my recent additions don't move.  I've used logs, beams, cants, and other lumber stacks for weight before, but nothing dedicated.  Yellowhammer has a good example with the pallets he puts on his stacks when they go into the kiln.  He has what looks like granite counter top scraps or offcuts on a lumber pallet.  

Anyhow I'm planning to make a form to pour some 4x8 3"-3.5" thick concrete slabs, with wire mesh in them that I can put on a lumber pallet.  One should be around 1500 LB.  Two of these on a stack should be good.  As I build a stack or add a layer, put the weight pallets back on.  I will make two of these weight pallets so that I only have to lift up 1500 LB at a time.  Once you get say 3 stickered lumber pallets, you'll have to lift the weight pallets a good height to get them on, so 1500 should be ok.

Do you have a good solution for weight?

[moodnacreek]

Bundles of like length 1 " boards, already air dry go on top of fresh cut. When I started I thought heavy beams should go on top but in practice that is not the way. 1" stuff if not high grade can bend a little and weight down a somewhat bowed pile better than thicker stock and later thicker stuff will not lay flat from it's own weight like 1" will. So thick on bottom, green thin on that and dry thin on top.

[JoshNZ]

I did exactly that. It results in better lumber without a doubt. I'd like to have a dozen more of them lying around, but it would be quite the saga to make that many of them. I put loops on top to make them easier to move so that I would use them but they interfere with where the baffle lands on top of the stack in the kiln, I'll probably end up cutting them off.



 

 

 

 

[RichTired]

I got some thick concrete sections of an old sidewalk/ramp from a local  church. 300- 400 pounds each. Works fairly well and no cost except to haul them home in my pickup truck. 

I have seen lots of 6-8 inch thick sections sawn out of the interstates around Birmingham. Not sure how to get some, they would be great to put on top of a stack of wood while it drys.
Some they regrind and some goes to fill. Hopefully not the land fill...

[SawyerTed]

My neighbor had his concrete driveway replaced.  He asked if I could use the chunks of the old driveway.  I put several chunks on a pallet and put the pallets on top of the stacks. 

[YellowHammer]

I would try to form forklift notches integral to the bottom face of the weight to get a flat top for easy stacking or storing.     

Maybe slide some 2x6" in a couple places on the form to the bottom for forklift slots that can be removed later.  A few pieces of rebar across the notches would help the strength in that area. So from a side view, it would look something like this: 
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[Vautour]

Great idea JoshNZ, Glad to see you still up and running after the assault you had on your Country, looked at all the pics that Ianab posted, just heart breaking.

[fluidpowerpro]

Last summer I made a bunch of weights by filling 5 gallon buckets with 1, 60 lb bag of cement. One bag does not fill it completely so once it dried I trimmed the extra off the top with a sawzall. I also bent some handles out of rebar and stuck them in the top. Although 60 lbs isn't a lot of weight, I can still move them by hand, and can strategically place a bunch of them on a stack. I have found that even a little weight on top helps greatly to keep the wood straight.

[Brad_bb]

Yes, YH that may be the way to go.  At first I was worried about weakness and the slab cracking, but with some rebar it may be ok.  I see you also put in some generous draft for the mold  ;D

[YellowHammer]

Yeah, I normally would have used my 3D modeling software but... I just used what was handy on the keyboard.   :D :D

[longtime lurker]

Best weight to have on a pack of timber is another pack of timber, just keep rotating the drier ones to the top.

[YellowHammer]

I air dry with stacks of wood as weights, also.  However, it's not unusual to develop "stack bow" on certain stacks od wood, and this condition shouldn't be stacked on other packs as weights as they exhibit characteristics of end heavy settling and will not properly weigh the stacks under them.

For them, I will put them on bottom until they have been flattened, then rotate them to the top when they straighten.  Or put them in their kiln and flatten them when I'm drying them with the concentrated weight packs.

If I out 3 green packs with stack blow on top of each other, when they air dry, I will have 3 air dried packs with stack bow.  Sometimes this can be fixed in the kiln sometimes not. 

[moodnacreek]

Those concrete weights are nice but I would not want the lift loops on top. I also hate putting tires on some of my pile covers because it ruins a flat surface.  When you are sorting with a forklift you want everything flat or with skids on top. You always need a place to set something down.

[FactorySeconds]

I would try to form forklift notches integral to the bottom face of the weight to get a flat top for easy stacking or storing.    

Maybe slide some 2x6" in a couple places on the form to the bottom for forklift slots that can be removed later.  A few pieces of rebar across the notches would help the strength in that area. So from a side view, it would look something like this:
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Sometimes the simplest ideas are the best, great stuff! We're going to build a couple as testers asap.

[YellowHammer]

Mine are flat on top, fork liftable from the bottom.  I simply put about 3,500 lbs of concrete chunks, broken slabs, or granite pieces on pallets so they can be handled easily.  Mine cost nothing, I salvaged all the granite and concrete for free.  

I'm not sure that if I wanted some built instantly, I'd go to Lowes and buy a few layers of bagged quickcrete, lay the bags evenly on 8 foot pallets and wet them down.  The weights don't have to be rigid, if they are pieces all on the same pallet, they work fine. 

Here is old video of how I do mine.  You can see the weight packs occasionally in the video but the main thing is that you can see how dead flat the wood is, even the top layers, because of the weight packs.  The secret is to have lots of weight packs, ready for use when needed.  Of course, nothing goes in the kiln without weight packs, ever.  However, having a few spares around helps address the malcontent air drying pack, also.  

Kiln Dried Wood Operation. How we kiln dry our wood at Hobby Hardwood - YouTube

[longtime lurker]

I air dry with stacks of wood as weights, also.  However, it's not unusual to develop "stack bow" on certain stacks od wood, and this condition shouldn't be stacked on other packs as weights as they exhibit characteristics of end heavy settling and will not properly weigh the stacks under them.

What are you attributing "stack bow" to?
This is you so I doubt it's thick-n-thin or sticker height variations because you're as OCD as I am about that kind of detail. So that leaves bow in backsawn boards which is unavoidable to a certain extent if the logs are springy.
If so, try stacking them sap side up even if there's no sapwood on the boards, you just want the growth ring orientation to be ⌢ way up. The stack might start off curled up at the ends but will settle out as you get some weight on it.

Old cypress sawmiller taught me that one, and after some experimentation I've got to say he was right.