Thank you, everyone, for your replies so far.
CB_Cohick wrote:
I would expect MDF to fall apart shortly following being placed outdoors.
I think most people “expect” MDF to do something particular outdoors.
A few years ago I made a rabbit hutch of MDF. I gave it two layers of glossy paint. It lasted two years (unfortunately longer than the rabbit). I also used left-over boards of MDF (painted with indoor paint, since they used to be cupboards) to make a temporary compost container (also outside) for a year long, and the boards are still in my shed because they still look salvageable for a future throw-away job (a little thicker than they were, though). In fact, I used some of those boards again to make a birthing cage for my other rabbit, and it was perfectly useable (although very heavy), and even now it stands unused outside in the rain, and still appears pretty solid.
Yes, MDF soaks up water, and eventually it behaves like wet cardboard. But I’m surprised at how long some of it lasts.
ChrisK wrote:
Take a piece of MDF and get it wet. Lay it out for an hour and see what happens.
Most plywood is made with glue that will resist water. The wood will rot if left wet.
Yes, but read my post—the frames will not be used in a wet environment. It is a dry environment, with high humidity, but if I don’t use MDF in the uppermost crate, no water will contact the MDF.
isotope wrote:
MDF … is not that cheap either. Plywood would better.
MDF in my area is half the price of plywood, and plywood is slightly cheaper than the cheapest knotty pine/spruce. The cheapest “ideal” wood to make frames from would be white poplar, but that’s twice the price of plywood, and not counting the costs to have it planed.
isotope wrote:
If you really want to save money, there are lots of opportunities to recycle/upcycle wood. ... Around here, there are many people giving away wooden tables, wooden dressers and shelves. Look for the ones that are made out of solid wood, not particle boards.
I have actually done that. I made some hives from very expensive (but unwanted) furniture—I have a crate here made from Brazilian walnut (used to be a couch). It’s heavy but I don’t use it on a hive that needs to travel.
The big problem is that it is extremely difficult to distinguish laminated particle board from real wood, even if you look at it and not just in a photograph. My current rabbit hutch (which must be replaced since it’s falling apart) was made from a “solid wood” television cabinet, but after six months it turned out to be just solidly made particle board. If I had cut the wood, I would have noticed that it’s not real wood, but I used the cabinet as-is (and added some doors and screens).
A problem with making frames from furniture is that most of the wood is not the right thickness, and I don’t have a planer.
Fred Hargis wrote:
Would the adhesives and whatnot in the plywood be a problem (I m sure the MDF would) for the bees?
No, the bees are more resilient than most people expect, and the honey ends up with only trace quantities of chemicals. I think it would even be safe to build hives using green treated gardening planks (not sure about those old chromated copper ones, though). In fact, we treat bees for diseases using chemicals, including e.g. oxalic acid (wood bleach).
And the chemicals won’t make it into the honey in any quantities that matter, unless the air has a very high concentration of it, or if the flowers have been sprayed with such chemicals recently.
knotscott wrote:
If you enjoy building them, use MDF or cheap ply. You’ll be doing it often.
Although beekeepers with larger establishments have equipment to clean old frames and re-use them for decades, hobbyists can’t really afford to re-use frames for more than 3-5 years. The effort of cleaning the frames is so much that it’s better to just buy new ones, and use the old frames as fire lighters. If MDF or plywood frames can be made to last 3 years, I’ll be satisfied with the cost/effort ratio.
You’ll hear stories about old beekeepers who had used the same frames (even the same comb) for decades, without sterilising them, but many modern beekeepers either renew or sanitise their frames at least every 2-3 years. Blame the varroa mite, having spread worldwide since about 1980. Mites cause injuries to bees, making them more susceptible to diseases left over in old frames.
-- -- Hobby beekeeper, Apeldoorn, Netherlands
