Fiberglass rod is a generic statement. Often for pultruded
glass/carbon/kevlar fiber and a polymer. So that leaves a lot of
choices including if the polymer is UV resistant. Glass fiber plus
polyester resin is the most common and cheapest. Probably UV resistant,
but worth checking with the supplier. A large hexbeam I was given had
all of the pultruded support tubes painted. steppIR has all trombone
fiberglass painted. So acrylic paint is one fix. I've used
glass-polyester on several beam driven element restorations.
Generic epoxy-glass material (eg FR4) is not UV resistant so unless
spec'd UV resistant needs painted.
Delrin (acetal) is an excellent polymer, but as others noted not likely
strong enough on its own as a 40m beam element insulator. A black
delrin sleeve over 6061 rod is another choice. My W6NL designed 40m
Moxon uses pvc sch 80 pipe inside and outside 6061 tube at the center.
Things to avoid - ABS pipe as it has a foam core and deforms. Nylon and
UHMW unless UV grades. Blue nylon has held up well for me as driven
element saddles and black UHMW for radial mast bearings.
Grant KZ1W
On 3/8/2020 10:09, Dave Sublette wrote:
Follow up Question. My browser now works. Go figure. Question: Is
there any other material (Delrin comes to mind) that you would recommend
for this application? The rod will be 1.5 inches in diameter and insert
at least 6 inches into each half of the dipole. This is a 40 meter
dipole and is heavy (75 pounds). It is supported by strut ropes, but
will be subject to bending horizontally and to some us flexing as the
wind generates lift. Some torque will be present for the same reason.
Keep in mind, I have a similar material that has been in service
satisfactorily for over a year on my pair of two element Moxons (without
strut ropes). So I'm sure this will work. I am just curious to have
the benefit of your experience.
Thanks,
Dave, K4TO
On Sun, Mar 8, 2020 at 12:52 PM Dave Sublette <k4to.dave@gmail.com
<mailto:k4to.dave@gmail.com>> wrote:
Well....it appears that something is out of whack with my browser. I
will try another flavor. I have two more available.
Thanks everyone.
Dave, K4TO
On Sun, Mar 8, 2020, 12:42 PM Grant Saviers <grants2@pacbell.net
<mailto:grants2@pacbell.net>> wrote:
McMaster.com FR4 to 4" diameter
Grant KZ1W
On 3/8/2020 09:29, Dave Sublette wrote:
> Some time ago (two years) I bought some 1.75 inch diameter
fiberglass Rod
> to use as a center insulator for my 40 meter Moxon project.
I bought the
> material from Max-Gain Systems, somewhere in Georgia. I now
get an error
> message indicating that the web page no longer exists. Does
anyone know
> where they went or where I can buy large diameter fiberglass rod?
>
> Than ks,
>
> Dave, K4TO
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