# Will doing OAV this way work



## enjambres (Jun 30, 2013)

Vapors being heated do rise, but I also see vapors escaping from cracks in my SBB over solid board, base, so they also do fall.

I have read here that people do stick wands in the top do it that way. Perhaps you could make some kind of special purpose box or shim that fits the wand. I would consider having some kind of docking/anchoring fitting to support the wand so you don't have to sit there holding it and can go about prepping the next colony. You'd need at least two, preferably three of these shims to allow for the three stages (burn/de-powered waiting period/sealed up waiting period. Make sure to leave at least two or three inches above the wand's surface to avoid cooking whatever is above it.

Be sure to close up any SBB, tightly, if you run with them.

Enj.


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## marshmasterpat (Jun 26, 2013)

Enj - Was thinking of a shim underneath, but lifting 2 to 5 mediums setting the shim in place and then treating seems like I would have lots of bees in the air for a while due to disturbance. Also having to move and stack the entire hive on the shim and then off the shim would start taking a long time. If that is the only method that would work, might just have to make new bottoms for them all. I am guessing they might just get the dribble method on the ones I treat this winter.


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## JTGaraas (Jun 7, 2014)

The instruction sheet provided with the Varrox Vaporizer says, "(i)f your hive bottom opening is too small to insert your vaporizer, you can vaporize from the top down! Just make a two inch shim the size of your brood boxes. Cut a slot along the bottom of the shim slightly larger than the rod of the vaporizer. Remove the top cover(s). Place the OA filled vaporizer directly on the frames." The shim is then placed on the hive, along with the top cover. It also suggests using something to avoid scorching (small piece of wood or sheet metal), and describes the process for the application. Seems logical, and the easiest since my mouseguards are already in place.


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## snl (Nov 20, 2009)

JT Garaas has it correct. Vaporization from the top down is just as effective. The vapors spread throughout the entire hive no matter whether vapped (is that a word?  from the top or bottom............. whatever is easiest or works for you!


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## FlowerPlanter (Aug 3, 2011)

>So it I put an extra medium on the top and vaporized on top of the hives, I am fairly certain it would not function well. But I am assuming that the vapors would rise and not fall

The vapors do initially rise from the heat but quickly fall. I read you get better coverage if you OVA from the top of the hive. But IMO the bees do move it around the hive by fanning just the same, if it was not for that action OAV would not work nearly as well. You can test this by OAV in an empty stack of boxes and watch were all the OV ends up. 

Here's a top shim with a viewing window so you can see exactly what is going on;
There is no guessing when the vapor is done.

https://www.youtube.com/watch?v=ALHz4B1vqKo


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## snl (Nov 20, 2009)

FlowerPlanter said:


> But IMO the bees do move it around the hive by fanning just the same, if it was not for that action OAV would not work nearly as well.


That's only true when the bees are not clustered. When final treating in between Thanksgiving and Christmas, the bees are most likely clustered. The vapors will penetrate the cluster. Think of the vapors as a mist coming from a waterfall...... it rises/falls and covers all.....


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## snl (Nov 20, 2009)

FlowerPlanter said:


> I read you get better coverage if you OVA from the top of the hive.


Source of this post?


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## AHudd (Mar 5, 2015)

FlowerPlanter said:


> >
> 
> The vapors do initially rise from the heat but quickly fall. I read you get better coverage if you OVA from the top of the hive. But IMO the bees do move it around the hive by fanning just the same, if it was not for that action OAV would not work nearly as well.
> 
> ...


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## FlowerPlanter (Aug 3, 2011)

FlowerPlanter said:


> >You can test this by OAV in an empty stack of boxes and watch where all the OV ends up.


Put a piece of plexy on top so the wind does not effect your results.


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## Sky (Jul 7, 2015)

Marshmaster - I have used OAV for a few years - my hive design does not allow vapping from the bottom - I have used a 3 inch shim/plexiglass on the top of my stack. Same process as doing it from the bottom, seal it up, plug it in, let it go for a minute or two (A plexi top is nice, you can see when it's done), unplug it, give it another 5 minutes to settle, then move on to the next one... 
Whether it works better from the top vs the bottom - I don't know having only gone from the top down.... 
what I can tell you is the within a few hours there will be piles of dead mites - way more than you ever imagined were even there.... 

Sky


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## Ski (Jan 18, 2007)

I have some hives that have short front entrances that the vaporizer will not fit into by maybe a 1/16 or 1/32. I have used a piece of rebar to pry the bottom board down or the boxes up with one hand and slide the vaporizer in the hive with the other hand. Not hard to do.


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## larryh (Jul 28, 2014)

I have one old bottom board that I assume is 3/8 and the varrox just barely slips in.. If it didn't fit, I believe I would just make 3/8 shim(s) to add permanently to the bottom board(s)


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## jmgi (Jan 15, 2009)

I vaporize from the top down and it works great that way. I really doubt that doing it from the bottom could be any better. My bottom boards that I constructed years ago myself do not allow insertion of the oav wand into them because the openings are too shallow, about 3/8" high. So I built a couple rims similar to feed rims, made of 1x4's. I put a slot for the oav wand "near" the bottom edge of the rim, and on the inside put a piece of 1x4 starting at the entrance slot, and going all the way across the rim to the other side, with sheet metal attached to it, for the wand to sit on, so it doesn't have to sit on the tops of the frames. I also put a piece of stiff wire, (like a hoop of wire) over the width of the 1x4" on the inside of the rim, so that it holds the wand from lifting up when you let go of it. Hope you can visualize what I am saying. I then stuff a piece of weatherstripping foam into the slot around the wand handle to seal in the vapors and put the hive cover on top of the rim. With the vaporizer running, the smoke can be seen coming from any cracks in the hive, including the entrance if it is not sealed tightly up. So I know the smoke is getting down to the bottom of the hive well enough to do its job, and it does. 

It still would be easier to just shove the wand into a bottom board opening (if the opening was high enough) but I would have to redesign and make all new bottom boards again, which is something I am considering doing. I know that the oav pan gets extremely hot, and I wonder how it doesn't melt comb down directly above the pan as it is vaporizing??? Maybe someone can comment on that, whether it does or not. Seems to me that even if you had a 3/4" high entrance, it would still be close enough to melt comb???


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## snl (Nov 20, 2009)

jmgi said:


> I know that the oav pan gets extremely hot, and I wonder how it doesn't melt comb down directly above the pan as it is vaporizing??? Maybe someone can comment on that, whether it does or not. Seems to me that even if you had a 3/4" high entrance, it would still be close enough to melt comb???


It will melt burr comb hanging down off the frames, so you want to keep those frames scraped clean, but interestingly it does not melt the comb in the frames. You need to keep the Vap solidly on on the BB so that it is not tilted up against the frame or it could melt the plastic frames it touches. 
I do both both top and bottom vaporization and that works equally as well. JMGI, you did a great job of describing the top down vap process.


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## jmgi (Jan 15, 2009)

snl said:


> It will melt burr comb hanging down off the frames, so you want to keep those frames scraped clean, but interestingly it does not melt the comb in the frames. You need to keep the Vap solidly on on the BB so that it is not tilted up against the frame or it could melt the plastic frames it touches.
> I do both both top and bottom vaporization and that works equally as well. JMGI, you did a great job of describing the top down vap process.


That is really surprising to me because of how hot that cup gets. I burned the end of my finger pretty good the other day on the darn thing because I forgot to dip it in water to cool it between hives! Having never done it from the bottom, I'll take your word for it that it won't melt the comb in the frames. I guess all I need to do then is make my entrances deeper by adding another strip of wood to the bottom boards to get them up to about 3/4" high openings. I really like having the shallower entrances though.


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## marshmasterpat (Jun 26, 2013)

jmgi - Thanks for the guidance


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## crofter (May 5, 2011)

jmgi said:


> That is really surprising to me because of how hot that cup gets. I burned the end of my finger pretty good the other day on the darn thing because I forgot to dip it in water to cool it between hives! Having never done it from the bottom, I'll take your word for it that it won't melt the comb in the frames. I guess all I need to do then is make my entrances deeper by adding another strip of wood to the bottom boards to get them up to about 3/4" high openings. I really like having the shallower entrances though.



Easy to increase your bottom entrance temporarily to do OA or to put an entrance anywhere between boxes. Pry up with a hive tool and slip the tapered shims in. I like to keep a bunch cut for spares.


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