Spars, Mast Hinge, Part 5: Tapping Holes in G-10 Step

The G-10 step with four, 5/16 inch screws
Having completed the construction of the G-10 mast step for Oystercatcher, my Ericson 25, my next task was to tap the holes necessary for the mounting of the halyard organizer plate, the base of the mast hinge, and the anti-compression block to the G-10 mast step. For this, I called upon a friend with a drill press. The G-10 had given me a hard enough time when I tried to screw rather small, #10 wood screws (3/16 inch) into it when constructing the step. Knowing that this new part of the project would demand large, 5/16 inch screws, I knew that if I had any chance of getting this done, I needed some assistance.
I had originally planned to mount the halyard plate and the other items with 5/16 inch wood screws. My friend said that it would be better to use 5/16 inch machine screws.
Accordingly, he pulled out one of many tap & die sets that he possessed in this machine shop that he had inherited from his grandfather - a shipyard machinist, legendary for his resourcefulness and his ability to craft things not by textbook approaches but by his sense of feel for the object with which he was working.
Using a table, my friend determined the correctly sized drill bit and tap for these 5/16 inch machine screws.
He began by drilling the holes. These holes, of course, were smaller in diameter than 5/16 inch.
The benefit, of course, of a drill press over a hand-held drill is that each hole will be perfectly perpendicular to the surface of the material, that is, assuming you have a good drill press and you operate it correctly.

After he had drilled the first hole, he installed the tap.
The tap, of course, cuts threads into the material and thus enables you to install screws into the material relatively easily.
The G-10 was unforgiving material and not very kind at all to my friend's tap. He made some headway into the G-10 with this tap before trying a different approach.
By using the hand-tapping attachment he was able to work the tap back and forth gradually cutting the threads deeper and deeper.
This traditional technique allowed him to avoid breaking off his taps in the G-10 while using the drill press.
At this same time, I called upon my friend to assist me with my construction of the G-10 anti-compression block. You'll recall that I had planned to use a piece of oak for this purpose. I ended up changing my mind about the oak after I cracked a piece of it off while countersinking one of the four, 5/16 inch holes in it.
I could have used my own miter saw/chop saw for this task, but I knew my friend had this old-school set-up that allowed him to clamp small pieces close to the blade.
After he had cut the anti-compression block to size, he clamped it to the underside of the top part of the mast hinge
He used the existing 5/16 inch holes in the stainless steel as a guide for drilling the four, 5/16 inch holes in the G-10 anti-compression block.
As gesture of thanks to my friend for this labor, I brought him a twelve-pack of that American classic, Pabst Blue Ribbon beer, or PBR for short. If you think that PBR was not a good gesture of thanks, then this probably wouldn't be a good person for you to ask a favor from.

The PBR had done much to calm the nerves and allow my friend to focus on the task at hand. The 5/16 inch machine screws were a perfect fit.

Now we needed to countersink the holes in the anti-compression block.

The 5/16 inch screws were a bit too long. To remedy this, my friend took out his die grinder and cut each one of them down to size.

That was just what was needed. The screws now fit perfectly into place.
Now that this task was complete, we could now focus on drilling holes in the G-10 step for mounting it into place on top of the old mast base/step.
This ends this posting on our tapping of the holes for the G-10 mast step for Oystercatcher, my Ericson 25.

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