Tappin’ It.

Greetings. Since I got back from my wedding, I’ve been working on making mounting brackets for the rails and the leveling feet. First I had to learn how to tap a hole. I’d never cut threads for bolts before.


Success! First test hole tapped!

The tap package should tell you what size drill bit to use. If not, check out this wikipedia article. Once the hole is drilled, put the tap in the tap wrench. I found it helps to put a little cutting oil on the tap before starting to cut the threads. On my first try, I found it was difficult to make sure the threads ended up perpendicular to the surface. I was using a 3/8″ tap on 5/16″ holes. I eventually decided to try drilling 3/8″ hole in a piece of bar stock to use as a guide to help keep the tap perpendicular. This worked great.


Got this because the giant mill in the hangar is placed in the corner, precluding drilling holes along the length of the 9 foot rails. Happy with it so far.


Drilling another 5/16″ test hole to be tapped for a 3/8″ bolt.


Drilling guide holes in bar stock.


Using the bar stock as a tap guide on my second test tap. The oil helps a lot. Also learned to back up every quarter turn or so to reduce friction and prevent breaking taps.

Then it was time to start making mounting plates for the rail. This process had a lot of steps since I wanted to use the plates as drilling and tapping guides for the threaded holes in the rails. First, I measured and drilled 5/16″ holes in the bar stock plates. Then I used those holes as guides to drill the rails. After that, I drilled out the holes in the bar stock to 3/8″ to use them as tapping guides. Once the holes were tapped, I finally drilled the plates on out to 5/8″ so there will be room for adjusting the rails for level and parallelism.


This shows my plan for attaching the rails to the uprights. The 3/8″ bolts are threaded into the rails through 5/8″ holes in the bar stock which will be welded to the uprights. This allows the rail to be shimmed to level and tweaked laterally to ensure exact parallelism with the other rail.


Using the mounting plates as drilling guides for the rail.


Using the plates as a tapping guide this time.


Finally drilling the mounting plates out to 5/8″.


Final configuration.


Ready to tack on the mounting plates.

Next I needed to cut off my ill-conceived corner wheel brackets and cut and tap some bar stock to accommodate the new leveling feet. Removing the brackets was a pain. First I tried to just use the die grinder with a grinding bit. This was painfully slow. Same held true with a cutting wheel on the die grinder. Finally I borrowed a reciprocating saw. This made it easy to cut off the two ends and then I could get at the welds with my full size angle grinder. This went a lot quicker.


Removing the wheel brackets.

Then I cut 2 inch squares of bar stock and tapped those to accept the leveling feet.


Ready to weld on the end caps for the leveling feet.




Leveling foot mounted.

After I had the leveling feet mounted, I tacked on the rail mounting plates and finish welded the risers. I’ll try to put up some pics of this in the next post. I’ll also be un-boxing and starting to mount the gear racks and v-rail. I’m pretty excited and nervous to start this phase of the project. Stay tuned!

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