These jars have been sitting here since May. I think the bigger jar bottom left has bigger chunks, and the 3 smaller jars have smaller chopped pieces. Is that why the bottom left jar looks so much better? Because the chunks are bigger?

I just whack mine into two or three inch squares with an axe, and always get quite a bit of good dark oil. Never seen the lack of oil like you have in the other jars unless a bunch of maggots got in them. Why maggots would cause it not to make oil I don't know, but one time I had some in a five gallon bucket and when I opened it I had a bunch of maggots and no oil. Only time I've ever had maggots and also the only time I didn't have a bunch of oil.

I’ve never seen any in there, but there’s flys buzzing around them sometimes. They vent through the cloth under the lids. Maybe I’ll give the other 3 a little shake and see what happens. I’ve got a box full of tails I’ll probably toss in a 5g bucket soon. I guess glass in the sun is better, but I saw a vid where a lure maker had 55g drums half full, was all black liquid on top. I’ll just leave it behind the garage until next fall.

Looks like the beaver tails, did not get enough Heat Units from the sun.

I prefer to use Black or Dark Blue Buckets when Sun rendering oils!!!

Also helps if there is a old vehicle with all the windows up. Place the buckets inside and they will heat up nicely.

You don't have to vent beaver tails. I didnt know that when I first did it and vented them also, but unlike most other things, beaver tails don't explode if you don't vent them. Yeah I like glass in the sun better, but I've made it in five gallon buckets a few times and it works just fine, you just can't look through the side and see how much oil you have. I usually leave it at least all summer or until the next spring before I make a draw, so if it goes a little slower it doesn't matter.

I would think there was enough sun. A native fella living about 500 miles north of me does it this way.
If I don’t let it vent, the glass will crack. On hot days it looked like it was starting to boil. My plastic 5g pail has a screw on lid and should have some flex. I’ll probably paint it black

Removing the skin and cutting in smaller pieces will yield a faster breakdown and oil release. I have done it in every way possible to speed up the process. Skin left on takes the longest to process and makes a darker oil. Skinning the tails yields very quickly with the smaller pieces. I can process bulk oil in a few weeks in a controlled environment and a couple months outdoors with solar heat only.

You need to put your cut up parts on a dark or solarizing surface to speed up your process. Not good to stack your containers. Build a small dark colored, painted or wrapped in black plastic container to really speed things up very quickly. Don't set your containers on bare ground as the ground temperature will work against the solar affect from the sun. Ground temps are much cooler then solar heated above ground temps.

I usually put them in glass gallon jars with the lid cranked tight and no issues. Can't do that with anything else I've ever tried to solar cook, but can with beaver tails. I do mine in the bed of an old pickup that doesn't run, seems to work pretty good, but I'm not in a hurry.

I’ve seen a video of a guy doing it quick on the stove with the skin removed but it didn’t have the same kick. He figured the skin with a little bit of fur at the beginning of the tail gave it the nice dark oil if dark is what you want.
I’ve also got time. The guy who said he wanted tails at $2-4CAD a piece backed out so I’ll use them for baiting and figure I’ll make some oil after hearing guys selling it to hunters. The stuff after the oil is rendered should be good stuff too.
After you suck up the oil with a turkey baister, sounds like guys get another layer on top after a while?

Yeah I leave it and get another draw the next year, just not as much. I do it with the skin on and get a real dark oil with a good smell. I have a five gallon bucket with about half two year old and half three year old chunks in it. The oil I drew off of it this year smells the same to me but I can pick the jar it is in out of the others by sight, noticeably lighter.

Thanks guys! I don’t think a guy can really do anything wrong with beaver tail, maggots would be the worst case scenario….lol

Maggots won't survive long if oil has already developed on top. If care was taken, and there isn't much tissue left on the material, it won't have the same "odor foot print" appeal as aging meat/tissue does to attract blow flies.

Pure fat has little appeal to blow flies, they only sponge it for the moisture content.

If some flies do break thru the seal it is easy enough to just strain the oil on your drawn transfer and they will be filtered out.

I got an 8oz bottle full. Hard to explain the smell, it doesn’t really stink, kind of sweet smelling.
There was a little bit of fur left on the tails, wasn’t much for flies, just the odd one investigating over summer. But I could smell it sometimes as a went into the little shed.