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diy oxalic acid vaporizer

262K views 261 replies 75 participants last post by  adammccoy 
#1 ·
I'm not certain how ethical it is to post this, but...
For some smaller beeks $100 or more for a vaporizer is pretty steep.
Make your own.

Drill a 3" x 3" aluminum bar stock to accept an autolite diesel engine glo plug (part #1107) and lock the heat element into the edge by tapping and inserting a #8 screw.
On the flat side drill 3/8" deep area to hold 2 tsp oxalic acid crystals. Drill and screw the aluminum piece to a 3.5" x 6" sheet metal (bend it up on the end to affix the handle). Connect the battery wires... + to the plug and - to the metal mounting plate. Put a spst switch in line with the 12v + lead. (fuse it if you want to be safe).

Viola !!! one vaporizer for about $20 bucks if you have a pretty good junk bin.

Johnny
 
#32 ·
Headnut, I like your slim oav version. Very professional done.
Mind giving the dimensions of each pieces? i.e. the block, drill size use, etc.
And where the negative terminal is connected to? I only see the hot wire connect to
the plug.
 
#169 ·
I used this drawing to make one. It is a bit bigger than the drawing and the milling of the dish is rounded corners. It only took 2:00 min to start and by 2:20 was over. But a percentage of it spilled out. Not too many shooting stars, but one blob all at once spilled out.

How can I improve this so it won't happen? Cut more of a dish out? Make the block bigger, smaller? I think maybe this design has too deep dish and not enough surface for when it begins to vapor on bottom and the top is still powder.
 
#37 · (Edited)
Using a propane torch as the heat source would be nice as its a lot of heat and lighter than a typical battery. The downside of the torch designs above is that you can't see the OA while heating it to know when you are done. Glass holds up well to heat. Maybe a small paint bottle with a decently thick wall would make a good reservoir. If one could find a small jar with a threaded neck and then get an air tight connection to a pipe, you would have a cheap and user friendly design. Just unscrew the jar to refill.

Or maybe one of those test tubes with a cork in the opening with a tube running through the middle of the cork.
 
#39 ·
Hello,
I am a newcomer; must excuse me if I make some foolish question.
I've been watching the projects that are in the forum to build a vaporizer oxalic. My first question is about the material: aluminum is suitable as a container for holding the boiling acid? It is not corroded by acid? I thought using stainless, but it is much harder to do machining at home. I prefer to use aluminum, if there are no drawbacks.
 
#42 ·
I built mine and paid around $25 for the aluminum. That bought enough to make about 5-6 units. Then with glow plug, scrap handles, wire, and clamps each will come out to be around $20-25 bucks. Order aluminum stock off of ebay. Hardest thing is hollowing out the acid "bowl" for me.
 
#44 ·
No, the aluminum will not react with the OA. Maybe this is a weaker acid.
I have made a simple small bowl out of the heavy duty aluminum foil.
Then use a small candle flame to burn off the OA at the
hive bottom with a 2" hole thru the bottom board. The hive must use shims to
raise it so the bees will not get burn too. After a few tests run I got it. And the
mites are dropping like flies after the first 2 rounds of treatment. I use 1/2 teaspoon
per nuc hive. And time it to 3 minutes then removed the flame.
It works though very primitive method for a small scale hobby hives.
 
#45 ·
beepro;120628l the burning experiment had failed!!!!!!!! Why? Because apparently OA in powder form does not dissolve in water that well. So another approach maybe needed like mixing with essential oil or something. OA sprinkled on paper does not burn well either. It solidified after got in contact with the fire. But I found a better way: I got it! Cost less than .10 cents to burn. And only took 30 seconds to see the vapor for a complete 2 minutes of clean burn (1 teaspoon of OA) using this process. No electricity is necessary using everyday household materials. I dare not to publish it afraid to put the oav gadgets out of commission. Got cough a little more than I wanted for not wearing my respirator. Got 2 mins of vid on it while burning and lots of good pics too. Yes said:
Did you mix it with drano? Also, I don't think it worked, if you see a small version of superman's house.
 
#46 ·
It works! The small shiny white OA crystals consolidated on my nitrile glove during the test
burn. When burning at the hive the fumes went all over the hive with some escaping
out the crevices too. I saw dead mites today. Did a treatment on last Sat and again yesterday.
Will do one more tomorrow. The bees seem o.k. after the OA burning. Mite level had decreased
significantly inside the hive. And did not mixed in with anything either, no drano only the OA powder.
Will be interested in when you can make better improvements on my primitive burning method. Already
got a better way devised for this process. Can you?
 
#47 ·
Here is another technique for you to try, Beepro ... :p

On the subject of untested ideas. Here is a poor mans method of OAV. Get a small metal cup. Walmart has some for about 99 cents for 4. place a lit hooka coal in it and then put a dose of OA on a piece of aluminum foil. Place that on top of the frames of your hive. cover it and walk away. you can come back in an hour or two or the next day and remove the cup. Not my favorite way to do it and you do not get that really great cloud like you do with the vaporizers. but it does work. I still keep coals and cups on hand. if I am running short on time during one of my scheduled treatment days I can grab those coals lite them all with a torch. drop them in the cups with a small pair of tongs. get the OA doses set up and drop them in the hives. I can treat 20 hives this way in about 10 minutes. When I get back from whatever. I can go back out and remove the cups.
 
#48 ·
Hello,

I have another question about the homemade vaporizer: is the temperature control.

- 1) The water of hydration leaves at 101.5 ° C (214.7 ° F) The water boils off leaving anhydrous oxalic acid crystals.
- 2) At 157 ° C (314.6 ° F) the oxalic acid starts to sublime (Directly goes from solid to gas)
- 3) At 189 ° C (372.2 ° F) the oxalic acid which has not yet sublimed decomposes to formic acid and carbon monoxide.

You do you use a temperature control system in your DIY vaporizers to prevent decomposition of oxalic?
 
#85 ·
Erlaita, to address your question, I'm wondering if a temperature switch might be the lowest cost solution to control the temperature in the range needed. PID or on/off controllers are much more expensive.

Here is a temperature switch that's rated for 15A and seems to kick on/off at appropriate temperatures. At about $8, it's not too expensive. It would turn the heat element off at 169C (336F) and kick it back on at 157C (315F) which should work for this application.



http://www.alliedelec.com/white-rodgers-3l11-325/70101866/#tab=specs
 
#55 ·
AC thermostats and circuit breakers are not designed for DC. Direct current tends to arc momentarily when circuit is broken and metal gets transferred from one contact to the other (pitting) I have played with them in making egg incubators. They work for a while and then fail to initiate contact on temperature drop.
 
#56 · (Edited)
Maybe those of you thinking Electric should consider using a rheostat (?) ( variable resistor) for control. I would monitor temp using the non-contact thermometer I bought for my day job ($25 at harbor frieght) but if I had to go buy the thermometer for this project,, that might exceed the cost to just buy a store bought unit?
I like the idea posted by DanielY in another thread, & quoted above about putting a coal in a cup, putting oa in a tin foil over it & walking away. I dont like the idea of setting my hive on fIre though :)
some one said they used 1/2 teaspoon of oa to treat a hive ... I got out my new scale I bought at walmart for under $20, set it to metric scale, enough sugar to see what 1 gram of sugar looked like.
sugar is 1/2 teaspoon per gram with this device.maybe I should measure the wt. of 4 teaspoons & divide, since this won't measure smaller increments than 1 gram. this might be 1.99 gram for all I know. I checked google for grams to ounces conversion, 28.xxxx grams per ounce.
I ordered 2 pounds oa from ebay, ($12, including shipping) should show up this week.
I guess I would _like_ a device a could carry from hive to hive like a smoker, stick the nozzel in the entrance & puff x number of times, or turn on a battery operated fan for x number of seconds, then move on to the next. I only have 4 , no 3 hives at home ( one died) & 3 at my mothers house, so I am really small scale. would be nice if the parts were something that worked for other uses too, not just once per year. batteries used once a year blah blah.
just dreamin'.
 
#58 ·
Testing one now without a PID controller but simply using the burn cup mass to keep temp below 350degF and the heating device below a 5 amp current draw @ 12vdc and only pulling 50 watts.(2g burnoff @<5min)
Also, have a compounder developing a safer delivery method for the OA.
Will be American made and hopefully American made parts. Still researching 1 item made overseas(China) and may be outa luck on availability here.
 
#59 ·
I did a OA weight in using my reloading powder scales in grains and did the multiple conversions. Tech. you might be advised to do 10 charges and divide if your scale has that coarse of graduations. Just from memory I came to the conclusion that half a teaspoon was a bit more than 2 grams but is what I use for a double deep.

I had the thought that it would be nice to have OA pellets of approx. 1 gram that you could drop down a snap cap covered tube into the temperature controlled pan. This way you would not have to cool the evaporator between burn offs. Probably the recreational drug boys could point us to a suitable pill maker and an anti hygroscopic coating for our mite pills!:rolleyes:
 
#60 ·
Compounder working on it now for 1/2, 1 and 2 g pills. The pill manufacturers want to use a lubricant for their machines to spit em out cause the OA crystals are I guess different, and I have refused to accept them with a lubricant. I have a small pill maker that is 8mm in diameter and can turn out several a minute but the pill makers can do thousands. I had planned on putting them in push out plastic pill dispensers so exposure to the acid would be less than using a scoop. They are available in Europe in a bottle but shipping is costly compared to manufacture here.
Anybody out there work in a pill manufacturing facility ? I talked with one in New England and the least they would set up for is a 1 ton run and their machines required lubricants.
 
#62 ·
whats that ol saying in the union shop ?
Give the nastiest, sorriest, hardest, most difficult that the brightest and best employee has tried to do to the sorriest, laziest, no count employee, and he/she will find the easiest, best, cheapest way to get it done.

I'm lazy and have worked around hazardous chemicals all my life as an Instrument/Electrical Journeyman in most of the chemical plants along the Texas coast and still hate being exposed to them.
I wear gloves and a respirator and sometimes a face shield if the bees will let me using the OAV. Get a mean spirited lady under a plastic faceshield and the sound and nearness is unbearable.
OAV works and works well on mites. How it don't bother the girls is beyond me. But chemicals have always fascinated me on how you can make, apply or swallow something so good outa something so bad to start with, is way beyond me.
 
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