Congrats on the harvest! You can definitely get more than an ounce from a small tower pc grow (I have done it numerous times if you check out my older threads). Skip the mylar (unless you're strapped for cash) and head straight to orca or panda film (it'll run you $15 as oppose to the $1 mylar sheet you can pick up at Walmart/Home Depot/Lowes), trust me on this I made the switch and the yield makes a WORLD of difference; you'll also notice how brighter the inside of your box will be.
Also with the drying/curing... it'll differ from house to house, setup to setup, state to state, but there was a very informative article/post put up on here when I first started by one of the top grow heads here (don't see him posting too much nowadays; I'll dig for it and repost here tomorrow when I find it), but you wanna dry for at the very least 1-2 weeks before you throw them in jars and start burping (then again I don't know what the temp and humidity levels are in your box, so I can't give exact estimates).
The best way to do this on a budget is to stick your buds in paper bags (paper will absorb the moisture a lot quicker than air drying; unless you have some sort of small fan or constant air circulation in that box of yours). I've done numerous side by side tests, in fact that's all I did when I first started out because of the amount of myths and lack of information on the subject. After about a week of being in the paper bag they should be sort of crispy... like when you squeeze them you should be able to feel the roughness of the leaves and feel a very slight crunch; that's when you know they're ready to be cured. Also a good thing to do is take pictures. You'll notice a very subtle color change difference between weed that is ready and weed that is not ready. The hue/saturation of the green turns lighter.
It's been proven scientifically (got a chance to check out a testing lab in San Francisco when I interned at Parnassus Hospital through UCSF) that curing bud increases potency; fact. The way THC and CBD and all the cannabinoids are processed and their cycles work is through humidity and temperature. Control those things and you'll have dank ass weed. Every cannabinoid in weed, just like proteins in general, run their course through their respective cycles and denature through heat and humidity, regardless of whether you harvested at 90/10, 80/20, 50/50 cloudy/amber trichs. If you don't take care of how you dry and cure them then they'll never reach their full potential (which in some cases and to some individuals it doesn't matter). Cloudy and amber and clear trichs just let you know how far along the cycle each cannabinoid is at during the stage of the plant. People say to wait for cloudy or amber because that's when THC/CBD content is the highest in production. There are several cannabinoids in marijuana that are still being mapped. Anyways, the article I read had these rules.
1) When you harvest your plant you're assuming that net water weight that the plant is still holding is about 80-100%
2) Generally, you're going to lose about 60-80% of you're total net wet weight through the drying/curing process
3) When you harvest your plant, because of the amount of water it still holds, the humidity (if you jar them quickly) is going to be way high; you should assume that humidity from a fresh cut plant is also around 80-100%
4) Drying should take the humidity levels from 80-100% down to about 50-60%; the idea behind this is you don't want your weed to be left in an environment where it can potentially grow mold as well as slowly letting the cannabinoids run through their cycle (sort of like the Krebs Cycle; if I recall correctly)
5) Once the humidity level drops down within range where the potential for mold is no longer a problem you can jar them and slowly burp them. The idea behind burping is there is still water remaining in the plant that it needs to get rid of to be some primo even-burning smoke; while yet again still giving the cannabinoids time to run through their cycle and reach their full potential. So the way you do this is leave it in the jar for a couple of days and then open it, releasing the excess humidity that has built up due to water loss and then seal it back up. I've been told you should do this as slowly as possible and I've done it in increments of 10%. So bud reaches 60% humidity, toss them in a jar, monitor humidity, humidity will spike, burp jar down to 50%, monitor humidity, humidity will spike, burp jar, etc. all the way down to 40%. Last I read 40% is the number you wanna hit for most of the cannabinoids to be ready and active.
It's a lot of work, however a cigar humidor company called Boveda has recently taken interest in cannabis and has developed a similar pack that keeps cigars at the right humidity for cannabis... and surprise... that humidity level that they sell their packets... 40%. I picked up a pack from Amazon for like $20 (I think?). It's pretty much a toss the pack in your jar and forget about it until the humidity reaches 40% which could take 2-3 weeks depending on how wet your bud is.
That's how you're 'suppose' to properly dry and cure them, but to each their own. I know I do it a couple of times here and there because no one likes waiting, but I've done side by side tests and the smoke difference is night and day.
I know this was a lot and I may be off with how I recalled things (it's been 4yrs), so I can admit to being corrected, but I will definitely hit this post back up once I find all those articles/info. I think it's only right you get quality info it being your first grow and all.
There's also nothing wrong with smoking if you need to lol. Everybody says not to, but I can openly admit when I'm hurting for it I'll smoke some semi-dried weed granted it's not the best.
*Forgot to add. Since the wet water loss has been studied in plants and is said to be around that % of 60-80, you can logically assume that you can simply keep taking weights every now and then until 60-80% of your original net weight has been lost and assume that it's ready to be smoked. I've done this a couple of times and it's been fairly spot on, again that's not saying that you didn't lost some cannabinoids due to degradation.
So for your 81.8g wet weight you could assume...
81.8 x .8 = 65.44
81.8 - 65.44 = 16.36g dry
or you could use 60% instead of 80.