Paraffin Dipping - Wax Penetration

[acbz]

I'm preparing to set up to dip around 1000 unassembled new boxes. Last time around, I dipped using a 55 gallon drum with electric band heaters, following recommendations to use a dipping temperature around 300 F. I dipped each batch at this temperature for about an hour. Post dipping, I cross-sectioned a few pieces and found that the penetration of the wax was not very deep (1 mm or less). I'd like to get a penetration of at least 1/8" - 1/4" this time around.

I know some comm. beekeepers who will put in a batch at a lower temperature and let it cook overnight, at a lower temperature than what I was using. I have too many boxes and not enough time to do one overnight batch per day, therefore I am trying to ascertain which variables affect wax penetration into the wood.
One observation I have made is that the wax seems to get drawn into the wood upon cooling: I left one batch in the tank and then unplugged the heaters while it was still at about 300 F, then went in for the night. The next morning, I found that the wood had soaked up paraffin like a sponge as it cooled. In fact, I found that theses pieces were much heavier than my 1-hour treated wood...much more paraffin than needed was absorbed.

Just curious if anyone has any recommendations as to a quick method for dipping woodenware which gives a decent penetration depth?

PS: I suspect that wax penetration may be increased by submersing/removing the wood from the hot paraffin several times in order to let it cool/absorb wax multiple times. I'm not sure if this will work, but I plan to do the following experiment to test my idea. I will use 7 identically sized pieces of wood and put them all into the hot paraffin at the same time. At 10 minutes, I'll remove 6 of the 7 pieces, set one of them aside, and re-submerge the other 5. I'll continue to do this at 10-minute intervals until there is one piece of wood which has been submerged in the tank for an hour without removal, and the other pieces which have been dipped multiple times (ranging from once to 6 times). Cross section everything to see if there's any difference in wax penetration depth.

[robherc]

<snip>I am trying to ascertain which variables affect wax penetration into the wood.
One observation I have made is that the wax seems to get drawn into the wood upon cooling: <snip> the wood had soaked up paraffin like a sponge as it cooled. <snip> ...much more paraffin than needed was absorbed.

Just curious if anyone has any recommendations as to a quick method for dipping woodenware which gives a decent penetration depth?

My first reaction is: don't waste your time double-dipping; once the first dip cools you'll have embedded, cooled wax in the way of future dips getting better penetration; you'll just be making "dipped" paraffin candles IMHO.

As far as the wax being absorbed upon cooling, this leads me to believe that there's still a good deal of moisture in your wood. At 300*F the moisture is all in steam/gas phase & takes up most of the space in the cells of the wood, "holding back" the wax, then as it cools to below 212*F it converts back to absorbed water droplets, taking up FAR less space, thus allowing better penetration of the wax.
That said, I have 2 potential suggestions for what I think will improve your wax penetration. In order of theoretical efficiency, they are:
1)Kiln-dry the woodenware before dipping (any way you can heat the wood before dipping should remove some of the moisture...the hotter it gets, the deeper the wax will likely penetrate)
2)Try dipping the woodenware in paraffin that's below the boiling point of water (212*F) so the water in the wood will mostly stay in liquid phase, thus taking up less space.

I'm guessing that option 1, if done hot enough & long enough, has the potential for giving you the same/better results as the boxes you left in paraffin for an overnight cooling, and should give you SOME level of control over the penetration (I'm betting that wood with the same moisture %, all other things being equal, will have about the same penetration depth)
Option 2 is likely to work too, but it seems like a bit less of a "controlled" method. Given the choice, I think I'd try option 1 & find a way to monitor the humidity level in the "kiln" so I could get repeatable batch results.


Just my $0.02, hope it helps!

[psfred]

Time is the major factor here, although higher temps will work a bit faster. Obviously, once the paraffin has solidified it's not going anywhere.

So long as the wax is molten, it will continue to slowly penetrate the wood. Leave it in long enough, and it will go clear through (but we are talking probably a month or so).

Dry is better than wet, but time is the real determinant.

Peter

[rainesridgefarm]

I dipped boxes 15 years ago in the same method that you did and they still look great. I think you are trying to hard to get more wax in the wood and there will be no benifit to it. any wax penetration in wood is better then just coating it with paint.

[acbz]

Just my $0.02, hope it helps!

Thanks a lot for the responses. Will update with results after I try out a few different setups.