Tried this on several hives last year and they're already needing major touch ups. Thoroughly melted, burned the mix in with my propane torch, reapplied, and repeated 3x. Never again. Am currently sanding and prepping to paint. Would be game to do a hot tank to try again, but without that Im sticking to a good latex paint. Just holds up better IME

 

If you want to keep supers from decaying, treat them with copper naphthenate. Use the type that is thinned with paint thinner and thin to a 3% solution. It is hard to find, but some Ace Hardware stores will have it. Years ago Lowes carried it in the 3% in brown color or green. The color will fade out to a brown over time. One treatment is good for 6 to 8 years depending on your conditions.

 

An easier way is to waterproof first then paint them.
Next is to put on a coat of finish in your favorite color and
apply a layer or 2 of linseed oil. Recoat the hive with linseed oil every season or 2 will
do. I've been using the composite particle LP boards for the hives.

 

Linseed oil makes for a pretty poor exterior finish. It generally gets used in locations of extremely high wear, and it is assumed that it will be reapplied frequently. Think tool handles, wooden workboat interiors, etc.
Adding wax does boost the protection level. It's hard to add enough wax to get decent protection without reaching a point where the stuff is too thick to apply unless molten.

I would never apply linseed oil over paint. Oil finsh is not meant to build a film, if you apply over an impervious surface and allow to cure your going to end up with a gummy sticky mess.
Sometimes a a worn chalky paint finsh will be given a light polish with oil to bring back the gloss.

 

Treat with linseed oil and allow it to sit a day or so, then paint with good quality alkyd primer, then with whatever exterior paint you want. Skip the primer if you want to use exterior varnish (spar varnish).

Otherwise the only really good finish for bee equipment is beeswax and rosin (not linseed oil, rosin is solid at room temp), and you have to dip it at above boiling temp to get it to penetrate.

I'd use linseed oil, primer, and paint myself. Spar varnish has to re-done every couple years, and I don't care for the extra work. Bees dont' care what color it's painted.

Peter

 

The linseed oil recoat will mix very well with the finish because
both are the same oil substance. The LP composite particle boards
will absorb the oil. After that a new coat will make the box shine to further
protect it from the elements. Let the finish completely dry out before putting on
the linseed oil afterward. This will give you a clear shine on the hive box.
After 2 years they are still in good condition.