Mast Assemblies and Internal Coax Runs
I recently required a mast assembly to use on my mobile with the 6 meter loop antenna that I built for my mobile.
For the mast I used a 4' length of thin wall 1" anodized aluminum, and machined up the 3/8" X 24 tpi threaded inserts that are pressed in to place at either end.
With the assembly installed on my mobile, it is required that the coax for the antenna is run down along the mast, which gives a un-sightly appearance to the overall build.
To clean up the appearance, and using a technique that I have used before, I drilled a hole at either end of the mast assembly, with the hole sized for grommets that allow the coax to exit at either end of the mast assembly.
The easy way to do this, is to first drill the holes to match the grommets, then insert the required length of coax through the mast.
You now can install the required connectors on the coax.
The last thing do do is to install the grommets by slitting one side of the grommet, and then using a blunt ended tool of approximately 1'16" diameter on the end, work the grommet into place in the hole surrounding the coax.
Another way to do it, is to slide the un-cut grommets over the coax from either end before installing the connectors, and work the grommets in to the holes in the mast, as that will work also.
Click on the photo for a closer look......
Bottom line is that you end up with a mast assembly that is pleasing to look at once it is mounted in place as seen here......