Please do not use locktite on a prop nut. This turns in to an ugly mess. The single cause for the prop coming off is that you simply aren't getting the prop nut tight enough when you tighten it down. This is very common, so don't give yourself a hard time over it. And I am sorry to hear about you needing stitches. First of all, if you are using one of those 4-way combo wrenches that is used to remove the glow plug please promptly deposit it in your toolbox and leave it there. These are bad for doing the prop nut because it's next to impossible to get the nut tight enough with one of these. The best thing to use is a box end wrench of the appropriate size for your prop nut. Also get a glove, or a good thick rag, to put on your hand that you are holding the prop with. This is done so that you don't cut your hand on the prop as you tighten it. Too many people are worried about getting the nut too tight and stripping the threads out. Don't worry about this because the prop shaft and nut are both made out of steel and will handle the pressure you put on it. With the wrench (and the glove or rag to protect you hand) tighten the nut as tight as you can. What I like to do is use the prop to help with leverage in tightening the prop down. Once you it tight as you can then grasp the prop and the wrench in the gloved hand and squeeze them together, this will use the leverage of the prop to get it a bit tighter. Do this and the prop won't come off any longer.

As a side note, if you are using wood props you have to check your prop nut and re-tighten periodically. This is because the wood will compress under the prop nut and become loose.

Ken