You know nothing about hash or oil if you think this is a good idea. Why are you using 151 and chopping up the weed? Also when using alcohol, never heat when evaporating, it just makes it dark and runny.
The best way to do this similar to this would be to get 99%iso, or as close as you can get. Don't chop or grind up the herb.
Freeze herb and alcohol for 30 minutes, a few hours is best. Put herb in a mason jar, add alcohol to the level of bud. Now you need to work fast, shake for 30 seconds or less. Closer to 15 sec is best. Have a metal strainer and coffee filter ready. Quickly pour alcohol mixture in the strainer/coffee filter onto a Pyrex baking sheet or something. Put the evaporating alcohol somewhere with a fan blowing over, in a well ventilated area. It may take up to 24+ hrs, depending on percentage of alcohol. Patience is key when it comes to evaporating, the more heat, the worst it gets. You could have a high grade yellow bomb ass oil that can even be solid so you can handle it.
However, with the method above, or using any heat for the alcohol, you will get Dark, bad tasting runny/gummy SHIT. You can ruin an otherwise great extract. That method above is for idiot high school kids, or people who know nothing about oil.