The system that I am working on will preheat the pan to 350 degrees so that when the OA is added it should vaporize in about 30 seconds, also the 3/8" nozzle is inserted into the hive so no hot pan is in the hive and no bees or queen can get fried.
I would be interested in seeing any figures of what temperature a plate needs to be to get OA to vaporize. as an example a 350 degree plate will not necessarily heat oa or anything else on it to 350 degrees. A more actual example is a propane torch heating copper pipe. The flame of the torch is over 3600 degrees. The melting temperature of solder is 360 degrees. anyone that has sweat a pipe knows that a propane torch does not get copper pipe to the melting temp of all that fast. So where is all that heat going. this is due to issues with thing like efficiency and heat transfer. some things resist taking het while others take it readily. and the heat will go where it is easiest to go. to the moisture in the air is one of them. the same will be true whether it is a metal plate or a flame. this example shows that in at least one case to get something to 360 degrees (copper pipe) it takes a while for even a 3600 degree heat source to get it there. there is nothing quick about it and to raise the temperature to above that would take an additional considerable amount of time.
Everything gets darker, as it goes to where there is less light. Darrel Tank (5PM drawing instructor)
Hi Daniel, it all depends on the efficiency of the system that will decide the amount of calories it will require to raise the temperature to any given temperature. All I can say is that the oxalic acid is dropped into a container that can be controlled to any set temp so the OA will sublimate rather quickly. Now what I want to see is to what temp the system will get to if not controlled, as the one I tested was not controlled and worked very well. From switch on to when ready took four and a half minutes.
I have posted some details and pics under VM vaporizer on the commercial postings.
I have now fitted a type K thermocouple to my new vaporizer and find it heats up to 350degrees in 4 minutes. Tried to check the accuracy of the read out by boiling water in the vaporizer and found it boiling at about 184 so I need to adjust by about 20 degrees if I can figure this mypin language out. I treated 14 hives at home this morning using 2 of these vaporizers allowing 5 minutes for them to heat up and then vaporizing for 1 minute per hive hoping to really cut back on time. So the total time to do the 14 ended up at 22 minutes not much time saved if I had used only one vaporizer. I think you lose more time going from hive to hive with 2 vaporizers than you would with only one. I will give them another shot in December and use only one and see how that time works out.
Too many opinions about temperature of vaporization.
Did anyone tried to make it using wood burner? I read it goes up to 950F.
For what it's worth - Champion 198 glow plug 140 watt 11v, shown as a replacement for Autolite 1104 127watt, at Rockauto.com for $3.61 plus about $2 shipping. I'm ordering 2 for $9.75 with shipping. 5% discount code 5607427050042966 enter in "how did you hear about us box."
About that heat transfer. I have that paste one uses between a motherboard and it's heat sink. If I pack that in the glow plug hole will I get better transfer
I've been through two autolite glow plugs today. I put my ampmeter on to monitor and an infrared thermometer as well. All looks good to start (14.5 amps and temp starts to climb but at 49 and 74 seconds the current flow stops. I pulled the glow plug and found they had ruptured both times. I drilled and tapped (10mm 1.25) the block to assure good continuity. I'm new here but ill try to attach a pic.
I took the nut off mine and drilled a tight hole. I then cross drilled and use a set screw to hold the glow plug in and help with heat transfer.
I must have the wrong glow plug. The model i bought just had a smooth shaft on the connecting end. Luckily the size matched a standard but spice connector. I'm reading on a diesel forum that autolight plugs are notorious for swelling and failing. Guess ill try to find another brand tomorrow. Oreillys only stocks autolite
Be sure to have tight tolerances where glow plug element makes contact with the aluminum block. I also used some heatsink compound in the assembly to get optimal heat transfer. I also have temperature control switch is series to make sure I don't overheat the glow plug. Typical car will only pump current for 10s of seconds max but we need to maintain temperature for 3-5 minutes so the temperature switch is essential.
The heating element is tapered. If you remove both nuts on the threaded shaft end you can push the heater out of the large mounting nut. Be careful not to short the connection when you connect the wires.
Found the problem. When all else fails, research lol. I asked the dude at oreilly of all glow plugs were 12v and he said yes. Turns out 1108 he sold me is a 6 volt plug. Going to NAPA this morning to grab a 12v 175W champion. Thanks for the replays.
It's been a few years and beekeepers are still finding this post when they Google long enough. This appears to be one of the most relevant threads on this topic. Where did you source the thermo disk? And are you still using this design?
Update: Do not use solder with any terminals on this vaporizer. The soldered joints will melt due to high temperature and current flowing through them. Instead, shrimp the connections.
Of course it’s better to buy the premade equipment. Some of us need to learn the hard way!
My 12 volt battery is dead, I had need to use my oxalic acid vap, I tried a golf cart 8 volt and it did not get hot enough. If I but two, 8 volt together to make 16 volts will that destroy my vaporizer. I have a Kelly beekeeping OA vap.