Making Kiln Pallets

[OakSavannah]

Fall is Full-On here in Wisconsin which means if you don't like the weather wait 5 minutes.  I've been studying Mr. Miltons ( @YellowHammer )  videos and his 4*8 pallets. (not sure on 4' but let's go with that for discussion sake)  I want to mimic this process of going from mill to air drying to kiln to secondary processing without re-stacking - and do it as economically as possible. Mr. Milton seems to use 4' 2x4 every 16" and 8' 1/2(?) boards on top. My question is when you sticker 2,000+lbs of lumber on stickers over the 2x4's and then lift it with forks, it would seem to me you would crack the 1/2" boards as they bend up the sticker height to meet the stacked wood. Suppose I could just add additional stickers to where the forks will go but looking for what has worked for you all along these lines - and as always appreciate the responses.  

[WDH]

I make the same pallets and use 1" pine boards for the long top boards and have had zero issues with pallet boards cracking. 

[Ljohnsaw]

Adjust your forks so they are relatively close to the 2x4 cross pieces?

[btulloh]

1/2" is too thin. 1" for sure. I don't think anyone is using 1/2".

Bottom boards could be 3/4, maybe even 5/8 and be ok. I use 3/4 on the bottom. The bottom boards turn the pallet into a torsion box almost and I are worth doing. Skids only have top boards and are fine for finished lumber. Opinions on skids vs. pallets vary, but I prefer the pallets for most of the handling until it's dried and dead stacked. 

[YellowHammer]

We started using these open bottom skids years ago because normal pallets were causing sticker stain and other issues.  The nail heads where the bottom layer of wood is attached to the runners will bleed into the green wood it is stacked on and leave little blue dots or iron stain.  The bottom of a normal two sided pallet will also block airflow and ruin the top layer of the wood it is stacked on.  So we removed the bottom layer of a pallet, turned it into a skid, and increased the runner count to 7 per 8 feet, which is how far apart we put our stickers, 16".

We experimented with different spacing but 16" give us the straightest and flattest wood.  The runners act as tall stickers, so that multiple packs of wood can be stacked and air dried on top of each other without staining, and have adequate airflow.  Don't use 4x4, or such thick wood for the runners, or it will sticker stain the wood the pallet it is stacked on.

Most of our skids are 42" wide and 8 feet long.  A standard 53' flat bed semi trailer or gooseneck trailer is 8 feet wide, and it's illegal for any cargo to project over the boundary of the trailer.  In addition, there is 2" of rub rail down each side, so a true 4 foot wide pallet won't correctly fit on an 8 foot wide flat bed trailer, which really only has 92" of deck space.  In addition, when we buy wood form other suppliers, their pallets are 42" wide.  So that is a "standard" size, although they can be any size you want.  

They need to be exactly 8 feet long (or 10' or 12' or 16') because it's not unusual to saw overlong foot logs and put the best section on the pallet, and then run a chainsaw down each end and "Pack Saw" them to trim them up.  So as long as the cuts are a few inches longer than the pallets, there is no way to mistakenly end up with short boards.  The other reason to make them all the same exact length is when they are stacked on other packs the 2x4 runners land directly on top of the stickers of the pallet it's stacked on.  That's critical.  If you don't get all the weight of the stacked pallets on the runners of the stacks below, then the wood will develop kinks. That is bad.

The easy way to make these is to lay one out on the shop floor, and use white spray paint and make an outline of the runners on the concrete.  The white doesn't show too much on the concrete but makes its very easy to lay the runners out and nail the top boards on them.  No wasted time with a measuring tape.  Set the boards down and pop them with a nail gun and make another.  They will all be exactly the same.

I use 2x4's for runners, and low grade cull hardwood, kiln dried and skip planed boards for the deck.  All the boards have been planed just like our other wood to 15/16".  It's critically important to make sure all the deck boards are the same thickness, and all the stickers to be exactly the same thickness.  It's not hard to do this, it just means being consistent.

We use two different fork machines to move the wood, each with different width forks and spacings.  The deck boards will flex but with the 16" spacing, and 3/4" (or even 1" thick stickers) they will not break or have any problems.  They can only flex 3/4" before they hit the first layer of wood.  We normally stack about 800 bdft per lift and we routinely pick up 2 stacks or close to 5,000 to 6,000 lbs, and the skids never get damaged from lifting that kind of weight.  There is really no load on the bottom boards, since they are made from the same boards as the stacked lumber, and use the same stickers, basically these skids are simply a bottom row of boards with the runners attached to them.  So they behave exactly the same as a normal layer of wood.  

You are correct, once the wood goes on the skid, it doesn't come off until it's kiln dried and dead stacked prior to planing.  Once the wood is planed, it get stored on them until they are sold.   Let the hydraulics of the fork machines do all the work.  This will save handling hundreds of thousands of pounds of lumber per year.

I appreciate you watching our videos.    

[customsawyer]

I use similar pallets but mine are 48"x whatever length of wood. All of my equipment has 48" forks and I've seen to much lumber get ruined when putting packs close to each other and the forks hit the pack behind it. 

[WDH]

Mine are also 48" wide.  They are either 8 feet long or 10 feet long.  I do not need longer as my kiln is limited to 11 feet maximum lumber length.  In hardwood, this length limitation is seldom a problem.