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Started by xlogger, August 07, 2019, 06:43:56 AM

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xlogger

I've been thinking about a better way to put weight on top of my wood, mostly slabs to help keep flat. As of now I use large cants of mostly white oak to sit on top. I was thinking about building some frames and having a concrete truck come out to pour them. Concrete weighs about 2000 a yard and if I make several around 1000 pounds with some kind of rebar to hold it together and with a way to run forks threw on top to sit it on stack and even put in kiln. Anyone tried anything like this or maybe show me something better. I figure each weight would cost around $75 for concrete plus what rebar cost.
When stacking for air drying I do stack on top of each other as much as I can.
Timberking 2000, Turbo slabber Mill, 584 Case, Bobcat 773, solar kiln, Nyle L-53 DH kiln

DWyatt

Quote from: xlogger on August 07, 2019, 06:43:56 AMConcrete weighs about 2000 a yard


Concrete would weigh closer to 4000 lb per yard which would be to your benefit. Around here it would be about $150 per yd like you figured. I feel like I remember reading something from @YellowHammer where he talked about reasons he didn't like using concrete (or maybe is was concrete blocks) and instead decided to go with the granite or quartz.

YellowHammer

I've have one kiln that uses a concrete weight and one kiln that uses marble and granite for weight.

I much prefer the marble and granite because it has a higher density than concrete so I can keep my kiln loads up, and not lose too much available space for the weights and rather use the space for the lumber.

Concrete also reabsorbs moisture fast. Marble doesn't. So if I put the concrete weights outside for any reason, so they will start sucking up moisture.  Next time it goes into the kiln, I will have to re dry the weights as well as the wood.  There is a definate time lag.  So they key is keep the kilns running and the concrete dry.  

Granite and marble also seems to hold heat better, and stays hotter longer, although I haven't actually calculated the heat loss.  So I have a little more time to re load and hot swap the kiln and not have to spend time re heating the weights.  

Either one will work, and I've settled on about 3,000 lbs to 3,500 lbs per 42" x 8 foot pallet of 800 to 1,000 bdft of wood.  You will notice a significant improvement in the flatness of you lumber, especially 9/4 slabs.  

I like to keep weights on the wood until it is cool, so will pull it from the kiln and put in our warehouse and place other pallets of wood on top.

I got my granite and concrete from a local marble countertop company for a little wood as barter.  



 

 
YellowHammerisms:

Take steps to save steps.

If it won't roll, its not a log; it's still a tree.  Sawmills cut logs, not trees.

Kiln drying wood: When the cookies are burned, they're burned, and you can't fix them.

Sawing is fun for the first couple million boards.

Be smarter than the sawdust

stanmillnc

Great info and reasoning Yellowhammer; thanks. The granite / marble pieces - how thick are they? Did you somehow bond together a bunch of ~ 1" thick remnant pieces to make one larger solid slab to sit on your stack?

mredden


I also have a friendly granite countertop fabricator who gives me scrap.

Standard granite tops are 3cm (1.1811 inches). You don't need to bond them together. In fact, you probably wouldn't want to given the weight of granite which, at this thickness, weighs around 18 to 20 pounds per square foot. Granite also comes in 2 cm (3/4 inch). It weighs around 12 lbs/sqft. #cm is used the most because of breakage issues.

The best thing is to find an oops countertop cut that is around 25" wide and 8' long. My guy's employees usually just take them to the graveyard and promptly forget about ever re-cutting them for later use. Also, they might be interested in tradeout for wood slabs cut to that size. Especially 25" one side live edge for use in cabin countertops.


charles mann

any thoughts to limestone? i was thinking of using concrete too, but if limestone would be better, the country I'm in is riddled with limestone quarries. granted I'm looking at this for air drying, and if whomever i used to kiln dry would be will to allow top weights, then the weights would go too. 

what are you using for stickers under the weights?
Temple, Tx
Fire Fighting and Heavy Lift Helicopter Mech
Helicopter and Fixed Wing Pilot

xlogger

Robert, on concrete do you use rebar? Also I guess you just pick the block up from the bottom or did you make something that your forks slid in? 
Timberking 2000, Turbo slabber Mill, 584 Case, Bobcat 773, solar kiln, Nyle L-53 DH kiln

Mike W

Charles, I would think Limestone would be about par to concrete for all things mentioned by Yellowhammer, with slightly less weight per volume then concrete, but if you have a good source to tap with reasonable pricing or even less then by all means beats parking your wife's car on top of the load :o

YellowHammer

On both my granite and my concrete, I use the simple approach and stack them on a pallet, same size as I use for my wood, so the weight is evely distributed on the lower wood packs.  I place the weighted pallets on top of the lumber stacks with a sideshift forklift.  

For the concrete, I've used a septic tank lid and old concrete pads, cracked down the center with my front end loader, and folded it up like a piece of bread and put it in the pallet.

I also have used quickcrete bags, and laid them on a pallet, kind of woven them together, sprayed them with a hose, and hardened them up.  

The problem is that the more room the weight takes up, the less wood that can go into the kiln.  So it's important to use enough weight, but not too much.  

You'll know when you get it right, when you put a weighted pallet on a stack of air dried and stickered wood you thought was flat, and you'll just see it just sink and settle down.  

It's als important to keep the weight on the wood until it is cool.  

Once you start using weighted pallets, you'll never put a stack of wood in the kiln without them.

YellowHammerisms:

Take steps to save steps.

If it won't roll, its not a log; it's still a tree.  Sawmills cut logs, not trees.

Kiln drying wood: When the cookies are burned, they're burned, and you can't fix them.

Sawing is fun for the first couple million boards.

Be smarter than the sawdust

charles mann

Quote from: Mike W on August 08, 2019, 10:11:12 PM
Charles, I would think Limestone would be about par to concrete for all things mentioned by Yellowhammer, with slightly less weight per volume then concrete, but if you have a good source to tap with reasonable pricing or even less then by all means beats parking your wife's car on top of the load :o
that is what i was afraid of, and thinking too, about the same, if not slightly less than mud. depending, it might just cost me fuel to go get them, esp if they are fall offs (fell off truck and busted) and no market for busted material.
Temple, Tx
Fire Fighting and Heavy Lift Helicopter Mech
Helicopter and Fixed Wing Pilot

WDH

It you put your wife's car on the wood for air drying, you won't be in the air drying business long and you won't have to worry so much about weight anymore.
Woodmizer LT40HDD35, John Deere 2155, Kubota M5-111, Kubota L2501, Nyle L53 Dehumidification Kiln, and a passion for all things with leafs, twigs, and bark.  hamsleyhardwood.com

xlogger

Still have this on my mind. I don't have any idea where I might get marble or granite, so I might just start out with concrete. I was thinking about making 4'x4'x10" forms (2 should be close to 4000") and 1 6'x6' one for adding on 10 ft slabs. My place here is full of soft ball size rocks and larger I'm always picking them up out of path, they grow better than grass, especially if I drive bobcat over them. Maybe add them in the form and pour concrete over them, to save on bags of concrete. I'll call concrete company first and see the cost of 1 or 2 yards delivered. As far as heating them up if they cool down that is not a problem for me. I heat my kiln with an OWB and cost is very little.
Timberking 2000, Turbo slabber Mill, 584 Case, Bobcat 773, solar kiln, Nyle L-53 DH kiln

GeneWengert-WoodDoc

Due to the acids in oak and some other species, rather than limestone, river rock concrete will last longer.
Gene - Author of articles in Sawmill & Woodlot and books: Drying Hardwood Lumber; VA Tech Solar Kiln; Sawing Edging & Trimming Hardwood Lumber. And more

WDH

I just load up a pallet with cement blocks.  However, because they are 8" tall and the pallet is 4" tall, this reduces kiln capacity.  For me, however, that is a reasonable trade-off as I absolutely will not tolerate lumber coming out of the kiln that is not flat.  I guess i could use 4" cap blocks. 

Ricky, if you loaded up a pallet with 4" cap blocks, that would be be very quick and easy to do and would not take up as much room as full sized cement blocks.  With the blocks, I have to blow off the stack with a leaf blower before planing to get any potential block grit off the wood.
Woodmizer LT40HDD35, John Deere 2155, Kubota M5-111, Kubota L2501, Nyle L53 Dehumidification Kiln, and a passion for all things with leafs, twigs, and bark.  hamsleyhardwood.com

scsmith42

I acquired some sidewalk slabs that a contractor was taking out. They are around 4' across, 4" thick and between 5' - 8' long.  They weigh around 800 lbs each+.  

Simply set 4x4's on top of the stacks above the sticker columns, and then fork the slabs on top.  Works well and they were free.
Peterson 10" WPF with 65' of track
Smith - Gallagher dedicated slabber
Tom's 3638D Baker band mill
and a mix of log handling heavy equipment.

xlogger

called a local concrete company yesterday and he quoted price of $468 for 2 yards of concrete. Ouch. I do have several cap blocks and lots of rocks that need to be  pickup and out of my way maybe fill them in with bags of concrete.
Timberking 2000, Turbo slabber Mill, 584 Case, Bobcat 773, solar kiln, Nyle L-53 DH kiln

Tom the Sawyer

I suspect that the short load fee, and perhaps a cleanout fee, might be what made it so expensive.  Do you have any concrete plants near you?  You might consider taking your form(s) to the plant.  If someone is coming back with a bit of leftover concrete, they could fill your form(s) before dumping it.
07 TK B-20, Custom log arch, 20' trailer w/log loading arch, F350 flatbed dually dump.  Piggy-back forklift.  LS tractor w/FEL, Bobcat S250 w/grapple, Stihl 025C 16", Husky 372XP 24/30" bars, Grizzly 20" planer, Nyle L200M DH kiln.
If you call and my wife says, "He's sawin logs", I ain't snoring.

xlogger

I was thinking about that also.
Timberking 2000, Turbo slabber Mill, 584 Case, Bobcat 773, solar kiln, Nyle L-53 DH kiln

GeneWengert-WoodDoc

It takes 100 BF of green oak or maybe 500 BF of air dried, lower density wood to give us 1000 pounds of weight.  So, we should see the effect of weight after about five layers in a stack.  That is, the lumber itself will provide substantial weight for the lumber below the fifth layer.  That is, top weights basically affect the flatness of the top five layers of a stack.  So, we need to make sure that the cost of using weights, including decreased kiln capacity, is not too high as the benefit is limited.  Almost all commercial hardwood drying operations do not use weights for this reason, but most do use roofs to keep the rain off the top layers.

When drying construction lumber, I was involved in a situation where weights were used in the kiln and then removed prior to five days or storage.  During storage outside, the wood continued to dry.  With this drying without the weights, warp occurred.  So, weights on lumber that will dry further after leaving the kiln is important.
Gene - Author of articles in Sawmill & Woodlot and books: Drying Hardwood Lumber; VA Tech Solar Kiln; Sawing Edging & Trimming Hardwood Lumber. And more

doc henderson

if lifting is an issue, could place empty containers on top and then fill/pump full of water for weight and then drain out to remove.  needs to be sealed to not add humidity, would create a thermal mass as well.
Timber king 2000, 277c track loader, PJ 32 foot gooseneck, 1976 F700 state dump truck, JD 850 tractor.  2007 Chevy 3500HD dually, home built log splitter 18 horse 28 gpm with 5 inch cylinder and 32 inch split range with conveyor powered by a 12 volt tarp motor

Mike W

 

 


How we are doing it.  We use our foundation forms which are 1 1/8" nine ply as the base form.  The notches are a true 4" x 2" with a slight bevel for easy removal once cured.  When we are pouring concrete on projects, we take one or two for the extra mud to get dumped into.  If no pours are scheduled, we are not short of any rocks around here and fill up to the cleat height, lay some welded wire mesh across with a few #4 bar (1/2") to help hold it all together, top off with more rock and just use mortar mix to fill it up.  Let set up, flip it over and strip the forms, slather it in concrete cure (all sides) this helps to keep it from absorbing any moisture back into the concrete.  our yard tractor has a lift capacity of 1800 lbs so this works great, at roughly 1000 lbs each it doesn't over tax the equipment and only 6" in height, if more weight is desired stack two, so we can easily get about 4000 lbs on our 8' long stock and only loose 12" of height, they are modular so we can play around with how much weight we want to load the stacks with pending the type of material we are drying.  Will try to remember to take a picture of the actual product when I am back at the yard.

xlogger

I'm getting started on building some boxes for concrete, I had a rock pile and several cinder blocks laying around I put in the boxes first. Then filled with concrete. Made two 4x4 and one 4x6. When I put in kiln for drying now I can use 4x6 for 6 ft, two 4x4 for eight ft and one 4x4 and one 4x6 for 10 ft. Got to make one more 4x4 for 12 ft.
Timberking 2000, Turbo slabber Mill, 584 Case, Bobcat 773, solar kiln, Nyle L-53 DH kiln

caveman

Just a thought inside the box.  For quite a bit of weight and probably less expense than concrete, one could fill in the gaps in a pallet, and add sides that go up a few inches and fill with used, lead tire weights.

Years ago when we started making our own fishing weights, several tire shops gave us buckets of used weights (turns out that they were too dirty to easily melt and pour nice weights with-lead pipe worked much better).  

Steel scrap prices are pretty low right now too.  Some plugs from an iron worker, though not as dense as lead, may be an option as well.
Caveman

customsawyer

I get my granite from a local guy that makes head stones. Any mistakes he makes he brings to me and we trade for lumber. ;D
Two LT70s, Nyle L200 kiln, 4 head Pinheiro planer, 30" double surface Cantek planer, Lucas dedicated slabber, Slabmizer, and enough rolling stock and chainsaws to keep it all running.
www.thecustomsawyer.com

WDH

You also won't need to worry about a grave marker when you go to that Big Sawmill in the Sky.  
Woodmizer LT40HDD35, John Deere 2155, Kubota M5-111, Kubota L2501, Nyle L53 Dehumidification Kiln, and a passion for all things with leafs, twigs, and bark.  hamsleyhardwood.com

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