Sunday, January 27, 2013

Commercial Migratory Pallet Design


One pallet design
Given the thin margins, hard work, and expenses associated with beekeeping, especially at a large scale, beekeeper have come up with many ingenious methods to save time and money.

While on my trip with Jerry to move his commercial hives to the orange groves of Florida, I was witness to some of these homemade ideas, some borrowed and some his own.  One of the most successful and one that has become a standard of the industry is the hive pallet.  Loading four hives (know as  four-way pallet) or six hives (a six-way pallet) on an easily movable platform provides a time and money-saving alternative to handling individual hives.  Commercial beekeepers (using a forklift) stack these pallets three-high on a flat-bed trailer to transport hives all over the country for pollination.  Best of all, the pallet when appropriately designed becomes a bottom board for the colony, eliminating that expense.

A truck carrying six-way pallets
Some beekeepers use standard shipping pallets for their hives, re-purposing them for this activity.  A better solution that maximizes the load a trailer can manage is a custom-made pallet.  One can be made with about $35 of new materials and is customized for 10-frame equipment.  That is considerably cheaper than purchasing four bottom boards.

Jerry uses these hand-drawn plans to build his pallets.

Our pallets are substantially similar, with the same bulk dimensions of 33" x 47".  We have added pressure treated lumber where appropriate, and assemble with screws for both stiffness and longevity.  What is the rationale for these nominal dimensions?  A flat bed trailer is typically 8 1/2 feet wide (102 inches).  Loaded, the 47 inch dimension allows for two pallets per row with an air space (an wiggle room for loading) of 8 inches in between each pallet.  Along the front, a 10-frame deep hive body is 16 1/4 inches wide.  The space created by the W clip is an additional 1/2 inch.  Thus two hive bodies plus the clip equals 33 inches across, and places the sides of the boxes flush with the edge of the pallet (in theory!!)

A typical flatbed trail is 48 feet long, allowing for approximately 17 pallets along its length.  X's two rows equals 34 pallets per level; x's three pallets tall equals 102 pallets; x's 4 hives per pallet equals 408 hives per load.  Why go through this math?  Well at $150/hive for almond pollination fees, that equates to $61,200 in fees per load (gross), for a 6-ish week period in California.  Those fees depend, of course on many factors not least of which is the health of the hive (at least 8 deep frames covered in bees) so much preparation and expense must go into the hives ahead of this trip.  Then there are agents fees for booking hives, transportation costs, hive wear and tear, and bee stress to consider.  But most commercial pollinators find it is worth the trip.  And the bee population explosion that occurs in the hives thanks to the plentiful food supply provides us hobbyists with our seed stock in Spring.

But now, onto the pallets.

Here is the materials list:


 And here is the cost at my Home Depot:

Here is how I built it:

I start by cutting my frame structure material to size.  The bearer boards are 2 x 4's cut 47 inches long, and the bottom slats are 4/5 x 6 material cut to 33 inches in length.


We move the operation indoors (yes, that is my living room floor) due to lots of cold and snowy weather outside.

We begin by laying out the exterior 2 x 4's and screwing (with 2" deck screws) our pre-cut under-deck 5/4 x 6 stringers.


Note that at this point we are only securing the stringers with ONE screw per end.  This will allow a modest amount of racking that we will use to our advantage to square up the pallet using the accurate squareness of the plywood decking.

We then tack in the middle 2 x 4 in the center of pallet, again using only one screw per end.

Now its time to turn the pallet over and add the decking, which is 3/4 plywood (23/32") in dimensions of 21" x 33".


 Note the 90 degree angle from the factory edge of the plywood.  We will use these two sides off this square edge to square up the pallet.  We then secure the plywood to the frame using 2 inch deck screws.

We then turned the pallet over and screwed in the additional screws in the bottom decking:


Now we have to install the furring to create the bottom board condition that raises the hive bodies above the decking by 3/4 inches.   We screwed the lengths into the deck with 1 1/2 inch drywall screws. We do this with 1 x 2's and 1 x 3's although one could just as easily, with a table saw (which we don't have) rip down some of the scrap plywood into lengths that would substitute for the 1 x's.  Here is how the wood goes in:



The 9 inch length along the front provides a reduced entrance to protect from robbing and wax moths.

The last piece is to install the W clips.  these clips hold the lowest super in place while providing a 1/2 inch space between the side-to-side supers to allow for ventilation and a space to keep clean.  These clips are attached along the middle of the 1 x 3 and are spaced front to back to prevent shifting.  I use a box I have handy to help set the clips.  Note, too, that the clips have a straight vertical side and a diagonal side.  This is to allow easier installation of the boxes.  have the angled edges face the entrance to the box on one side, and the rear of the box on the other.  Use a spare box to space them properly.

We space the clips so that the back of the box is flush with the back edge of the decking.
Rear of boxes.
The front of the box sits partially back from the front edge, allowing for a little more landing space, and providing partial relief to the front of the boxes from the wear and tear of lifting forks.

Set the clips so that the edge vertical of the clips in the forward and rear-ward position sit snugly against the interior front and rear panels.  This will prevent shifting of the boxes forward and back.

View inside the box of position of the clips.
We secure the clips with our drywall screws.


 And that is really all there is to it.  We will repeat the process on the other side of the pallet, adding the riser furring and the W clips, and we will have a pallet that fits four 10-frame hives (a four-way pallet).

You can see how that by custom making the pallets rather than jury-rigging a standard pallet allows for saved trailer space and material longevity, eliminates the need for a separate bottom board, and makes quick work of switching out hive boxes if necessary.

This pallet is HEAVY.  A little more than 50 lbs unloaded.  That exceptional weight is primarily due to the used of the new pressure treated lumber.  Eventually much of the moisture currently locked in that lumber will evaporate and the weight will decline.  But that is certainly material when calculating the load weight for transport.  A typical trailer can haul 48,000 pounds.  In our 102 pallet example, that's over 5,000 pounds of pallet alone.  That leaves only 105 pounds available per hive of additional weight.  That's pretty tight when you are running 2-deep configurations with lots of resources and bees, and when you have to include the weight of tops, bee netting, spreader boards, beer, etc.  You get the drift.

Also, in order to ship in such quantities and properly secure the load, standardization of equipment is paramount.  you want the tops of all your hives at the same level when you reach the top of the stack.  If you substitute 1/2 inch plywood over 3/4 inch ply, or use 1 x material for the bottom decking vs 5/4 material, those 1/4 inch differences add up over a three-high stack of hives.  Pick a design a stick with it!

There are many modifications one can make:
  • Substitution of No 8 screening for the decking to make ventilated bottom boards:

These designs would appear to have the one flaw in that lifting forks might be murder on the screening if not lifted properly.
  • Nails instead of screws...yes I love to screw things together but nails and staples are excellent fasteners and a pneumatic gun would make quick work of these pallets.
  • Untreated wood will make these pallets much lighter.
  • Using the plywood scraps for the risers/furring strips with reduce further the cost of the pallet.
And for those who want a video....here you go!


Thanks,
Jeff.







8 comments:

  1. I see did not make these pellets according to plans. It may not make a difference on a little truck but if you put these pallets on a tractor trailer you may be over Height.


    Jim of MA.

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  2. the only additions to height from the plans are an extra 1/4 inch from the 5/4 skid and an extra 1/4 inch from the plywood deck. All other vertical dimensions are the same. 1/2 and inch extra over three-high stack of pallets would surprise me if they would be over-height (1 1/2 inches) vs the exact replica of the plans.

    ReplyDelete
  3. I see you've missed a few like 1x3" not 2x4" and
    1/2" plywood not 1" furring strips I do see you got the plywood deck and the skid
    (This is why the wood as rough cut for pellets to get the full dimension)
    You also need spreaders on the top to help stabilize the load and your pellets will weigh more then the original plan there are two things you looking for Height and weigh do you want carry wood down the road or more bees.
    If you would like to carry more bees down the road follow the original plan it is as posted here


    Jim of MA.

    ReplyDelete
  4. You make a mistake when placing the "exterior 2 x 4's". As per the drawing they do not go at the end, rather a bt to the center so the stand clear on top of the hive roof that goes under it when in the truck pile.

    ReplyDelete
  5. Can you give build info on the screened pallets?

    ReplyDelete
  6. On a slightly different subject, do you have a company you would recommend for the shipment of jars of honey and the combs? Someone who would handle with efficiency and delicacy? I've been looking around but thought you would be a good source to ask.
    Thanks,
    Martha

    ReplyDelete