Comments on: Precision Drilling Repetitive Hole Patterns

By: blindleader

blindleader — Fri, 02 Mar 2012 18:45:00 +0000

If I had 20 holes to drill in each work piece, I could do it with 5 stop blocks as long as all their spacings were some multiple of one minimum spacing. Those 5 blocks would be sufficient to drill up to 32 holes, subject to the above restriction. How to do it is left as an exercise for the geeks among us.

By: Steve Shanesy

Steve Shanesy — Wed, 29 Feb 2012 14:34:01 +0000

I’d agree that stacking 20 blocks, or even 10, would be taking this approach too far. But as for letting inaccuracy occur in individual blocks, that would defeat the whole purpose. Dial calipers can measure each block to within a couple thousands so long as the individual block isn’t longer than the caliper can measure.
In my experience, most variances were the result of the bit drifting slighting, especially when it’s starting and even more so if the wood is course grained, like oak or ash.

Steve

By: sbmathias

sbmathias — Wed, 29 Feb 2012 04:44:09 +0000

One note about using multiple stop blocks. If each one is just a tad long, then stacking them up makes the error multiply. This is especially noticeable when you have a lot of blocks, such as when you need to drill 20 holes in a row, for example. If each block is just 1/64″ (0.015″)long, you would be off 5/16″ at the last hole! Cumulative error is the proper term.

A more accurate way is to make a separate block for each hole position. So, you still have 20 blocks to make, but if each one is 1/64″ off, then any hole is only 1/64″ off.

By: almartin

almartin — Tue, 28 Feb 2012 16:09:28 +0000

“This may not break new ground for some of you, but I suspect there are others who will find it helpful.”

No matter how experienced any of us may be, there is always something to be learned. Thanks, Steve, for a very helpful video.

By: rickclark9@hotmail.com

rickclark9@hotmail.com — Tue, 28 Feb 2012 16:00:24 +0000

Really like the stop blocks, but please put a lapel mike on someone in your new workshop. It is more 55 gallon barrel than Carnegie Hall.

By: decarlowoodworks

decarlowoodworks — Tue, 28 Feb 2012 14:17:08 +0000

Great stuff Steve, keep the videos comming!

By: Fred West

Fred West — Sun, 26 Feb 2012 17:56:00 +0000

Steve, great video. I agree with Dave that the stop block pieces is what made the video tip. I have used stop blocks for years but never thought about relieving a portion as you did. Thank you.

By: Dave

Dave — Fri, 24 Feb 2012 16:54:15 +0000

The stop block details really make this a great video tip.