Slippery Smooth Rails

Creating the Rails

Earlier, I had purchased the rail material, but I discovered that, unlike advertised as 3/4" x 1/8", it was actually 0.130" x 0.755" and had radiused corners. The bad part of this was even such a minute change is pretty serious in SolidWorks. If an assembly is not set up correctly, all the 'mates' will crash and you will have to go through and re-evaluate each component, especially since I have cut all the MDF parts out already. I can still adjust the method the rails are installed with, and adjust the dimensions to allow it to still work. I was going to cut grooves into the support members at 45 degrees with the table saw to accept the 'legs' of the angles, but trying to determine the measurements in real life was just too difficult. So, I changed plan and decided to use a set edge distance and use the router to carve a rectangular slot to a specified depth and of precision width to snap the angle into. It has required me to create a setup for the router so I can control it with precision. Having solved that problem, I can now go forward with the creation of the actual angles. The first process is to cut them to the required lengths: 79.5, 42.288, 15, 8, 5 inches.
I have a cool support stand for my chopsaw, so I brought it outside and set it up.
I measured very carefully each part, starting with the long ones first.

Long ones first-cut to split the line

Chopsaw set-up with 12" carbide blade

Always pre-trim the end to make sure it is true

Look close-measure 42"(from 10, burn 10), then .288"

All the rails cut-scrap is on top laying sideways

Top view of the parts-nice day

After careful measuring-microdot, centerpunch, center drill

Centerdrill-does not flex; results, then 7/32", then Letter 'I' drill

Learn to adjust your drill press speeds

7/32" intermediate holes completed

The 16-speed drill press I use

Harbor Freight 115 piece HSS drill set: Fractional, Number, Letter

The super tapper-$85 at Grizzly

Tapper counterweight transfer wheel and support bushing

Makes perfectly perpendicular holes with ease

Don't forget to use aluminum tapping fluid for nice threads

Completed 5/16"-24 threading-I hit it lightly with a chamfer to clean it up

So shiny new threads

The tap holder assembly-snaps into shaft

Preparing to install bearings



Snug the allen head bolt tight to the nut

Don't over tighten the bearings in the rails-The aluminum is soft

Completed X-axis support rails-note stagger on bearing holes

End view of rails showing clearance of rail 'points'

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