Re: Drilling an Avail 16ALD15 Spool
Posted: Thu Mar 14, 2019 4:57 pm
Yes Mark, your formula works as well. There are several ways to calculate circumference, however the answer will always be the same. I calculate by using the radius, because I make a lot of sheet metal arcs, and I justy happen to remember my formula from years of doing it.mark poulson wrote:Really nice! Is that formula pi D?cadman wrote:I would map out all the holes on a piece of paper with their center point for drilling (like a drilling template) like mentioned above. See attached Pic below. Then carefully tape (or glue spray adhesive) the template around your spool. Next center punch all of your holes centers on your template transferring them to your spool. Remove paper template and slowly start drilling: What you will need:
Piece of thin paper:
compass or circle template
Staggered hole center dimension
Hole diameter size:
To calculate the length of piece of paper to wrap around your spool, here is the formula. If your spool diameter is 1"diameter like in my example, then you take;
1/2" which is the radius of 1/2 of your spool diameter x .017453 x 360 degrees. So
.500 x.017453 = .0087265 then take .0087265 x 360 degrees = 3.14154"
3.14154" is the length of paper you will need to wrap around your 1" diameter spool from end to end. In my example, my spool height is 1", yours will definitely be different.
If your spool diameter is different then take that number divide by 2 and use that as your radius and calculate as above.
Once you are sure that everything works, you can locate your centers on your paper, from end to end.You can do in line or staggered holes, your preference. The critical thing here is accuracy. If you are off and something moves, your spool will be off as well, possibly throwing it off balance. Measure 100x cut once. Once you have the paper laid out on your spool, next would be to centerpunch and then drill. To drill use all the help you received above and go slow and think it out thoroughly.
If you need more help to figure this out PM me and I will help you.