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KI4YIK
04-28-2012, 06:41 PM
Where can I get insulators or how can I make them without ordering online from places like Gigaparts?

WA6MHZ
04-28-2012, 06:48 PM
I just took a hunk of board and drilled a coupla holes in it. Cost? Absolutely FREE!

AD6KA
04-28-2012, 08:24 PM
I've drilled holes in 3" or 4" long scraps of 1/2" to 1" PVC pipe
to make wire insulators.
Every DIY'er has scraps of those around, or ask a neighbor.
or use wood, as posted above. (If I lived in a REALLY rainy
area, (>50 inches/year) and used wood, I'd throw a couple coats of
Marine Spar Varnish on them. But that's just me.

IF your wire antenna is going to be long, heavy, or high up
in the air (pain to get up and down) then consider "Strain Relief"
type insulators. A Google Search will find you designs you can copy
in your shop.

Some may say "UV Rays will make the PVC brittle and crack".
Not in my experience, I live in So Cal: Hot, Dry, Sunny, almost
all year round. Never had a PVC failure due to WX.

73, Ken AD6KA

AB9LZ
04-28-2012, 09:06 PM
Plastic plumbing tee's make for good center insulators. Never had one fail in a decade of use.

73 m/4

KB4QAA
04-28-2012, 09:34 PM
I love this page from the army field manual on communications:

92000

K8ERV
04-28-2012, 09:39 PM
You might check electri fence insulators, I'm not too familiar with them.

TOM K8ERV Montrose Colo

K9STH
04-29-2012, 01:01 AM
PVC pipe 1/2-inch in diameter costs like $1 for a 10-foot section here in the Dallas, Texas, area. Depending on the length, you can get a LOT of insulators from a single 10-foot section. Just drill a 1/8th inch, or so, hole through the pipe about 1/2-inch from each end. Pipe in either 3/4ths inch diameter or 1-inch diameter is a little bit more but still not anywhere near being expensive.

The white PVC for my swimming pool pump has been exposed to the Texas sun for right at 30-years. Absolutely no chalking or other damage. Years ago, PVC pipe was subject to ultra-violet but anything made in the past over 3-decades seems to be fine.

Glen, K9STH

NA7U
05-04-2012, 12:18 AM
I usually use PVC cuz it's handy, but it really should be painted to prevent UV damage (most of my antennas don't stay up long enough for that to happen, though, always experimenting ...). Zareba makes some good and cheap UV-proof fence insulators in various sizes. I've used them to build ladder line, but they'd be fine for antenna support. I really prefer glass/ceramic insulators because I think they are classier. The HW stores around here have lots of them and they are not expensive at all (after all you only need 2-4 of them). The cheapest way to do this is to simply solder loops on the end of your wire and directly attach the rope!

K1DNR
05-06-2012, 02:22 AM
These are $1 a piece. Sold by many vendors and on EBAY. No drilling/cutting/sanding required. www.grumpyshop.net

WA7PRC
05-06-2012, 02:29 AM
Where can I get insulators or how can I make them without ordering online from places like Gigaparts?
Davis RF (http://www.davisrf.com/) is my supplier of choice. They stock Daburn porcelain compression (aka "egg") insulators, as well as just about anything else you might need for a wire antenna. You can make insulators out of anything insulating that's strong enough but, unless you need a boatload of them, you won't save much.

K8JD
05-06-2012, 03:36 AM
Those electric fence insulators have a hole thru the center for screwing them to wooden fenceposts and a groove around the outside to wrap a fence wire around. I don't see any use for them for a dipole !

K8JD
05-06-2012, 03:40 AM
MFJ sells end insulators for about a buck a piece in six packs.
The center insulators offered by many dealers are too pricey for me and I made mine out of a square piece of plexiglass with holes drilled in the proper places to secure the element wires and coax.

NA0AA
05-06-2012, 03:51 AM
Never really came up with any clever insulators since I find the commercial ones cheap enough for me, but any sort of PVC pipe drilled should work - if it's really big stuff, you can cut it into strips. I'd paint it just to kill the white.

Wood works as well.

Any sort of plastic that is mechanically strong enough although in time UV exposure might destroy it.

Cheap and quick? Zip ties in a loop - now I know that won't last very long - even black zip ties in sun crack pretty fast.

WA9SVD
05-06-2012, 01:40 PM
These are $1 a piece. Sold by many vendors and on EBAY. No drilling/cutting/sanding required. www.grumpyshop.net

If I'm going to BUY ready made insulators, whether from ePay or a retail dealer, I'd prefer true ceramic insulators. They do NOT degrade with weather or UV exposure, and are far, far better insulators (physically and electrically) than plastic. Under tension, wire will eventually "cut through" plastic insulators, leading to failure. Consider the voice of experience.
Most of the plastic insulators sold by Rat Shack and similar sources may be fine for a temporary (Field Day?) antenna (and we all know how temporary antennas tend to become permanent!) or SWL antennas with small gauge wire.

WA7PRC
05-06-2012, 08:01 PM
If I'm going to BUY ready made insulators, whether from ePay or a retail dealer, I'd prefer true ceramic insulators. They do NOT degrade with weather or UV exposure, and are far, far better insulators (physically and electrically) than plastic. Under tension, wire will eventually "cut through" plastic insulators, leading to failure. Consider the voice of experience.
Most of the plastic insulators sold by Rat Shack and similar sources may be fine for a temporary (Field Day?) antenna (and we all know how temporary antennas tend to become permanent!) or SWL antennas with small gauge wire.
Exactly. Also, when a strain insulator fails, the wire falls, leaving the end of the support up in the air. That's why I prefer compression (aka "egg") insulators. When they fail, the wire is still supported, and the insulator can be replaced much easier. Davis RF ("http://www.davisrf.com/) and some others sell porcelain compression insulators from small to large sizes.

K0BG
05-06-2012, 09:33 PM
Here's a few things to think about. If you run low power, and your living area isn't damp you can get by with just about any insulating material. However, if you run high power, or live in a wet part of the country, the end insulator in question needs a long arc length. This rules our most egg insulators used as they should be—in compression. Great for guys, lousy for antennas.

Most decent end insulators (remember, that's where the high RF voltage is) have several ring/groove cuts to increase the arc length. The longer the better too. Even the old HiGain "5 kV" insulators will arc over in damp weather even with moderate power.

As I said above, at low power you can get by with anything. But out there at the and of a dipole fed with one kW, PVC (especially the gray material) is not the stuff of champions.

WB5WSV
05-06-2012, 09:42 PM
I bought some "P-4H-75D PORCELAIN STAND-OFF INSULATORS" from Fair Radio. They are ceramic, about 4 inches long, are threaded internally for a mounting screw and cost about $1.50 each.

When I next take leave of my senses and venture into my attic to string a longwire antenna the length and width of my house, I plan to use them as stand-offs to isolate it from the wood structure.

Robert
WB5WSV

WA4OTD
05-06-2012, 09:53 PM
In 1976 I used to just cut up plastic milk jugs. They always broke within a year or so, but they were readily available and easy to cut with scissors.......

WA7PRC
05-06-2012, 11:48 PM
I've been using the Daburn #10-72 (http://www.daburn.com/10-73daburnairplaneinsulators.aspx) compression (so-called "egg") insulators for 42 years at the kilowatt power level on the ends of dipoles and other hi-Z (high voltage) points, in the Great Pacific Northwet. ZERO flashover problems. Ever.

N0LWF
05-06-2012, 11:51 PM
Go to your local farm store and get some electric fence insulators. It's all I use since I am a farmer and have 100's laying around.

N4UM
05-07-2012, 12:15 AM
I like to cut up Lexan cutting boards inhto 1" strips. They make good insulators.

AB2T
05-07-2012, 04:38 AM
In the past some hams would use paraffin-saturated wooden dowels as insulators for ladder line and wire antennas. Hams would boil the dowels in the paraffin until the rods were well permeated. The abundance of porcelain and PVC insulators renders this method obsolete. Also, wood will inevitably warp when exposed to moisture.

73, Jordan

WA9SVD
05-07-2012, 09:37 PM
Exactly. Also, when a strain insulator fails, the wire falls, leaving the end of the support up in the air. That's why I prefer compression (aka "egg") insulators. When they fail, the wire is still supported, and the insulator can be replaced much easier. Davis RF ("http://www.davisrf.com/) and some others sell porcelain compression insulators from small to large sizes.

I thought that was the only kind of ceramic insulators available... OK, my mistake I wouldn't use an "egg" insulator for the CENTER insulator of a dipole. There ARE good quality ceramic insulators for dipole center insulator use.

K9STH
05-07-2012, 10:19 PM
"Dog-bone" ceramic insulators have been available since at least the 1850s having been used in land line telegraphy.

Nothing wrong with using an "egg" at the center of a dipole. If, for some reason, the insulator fails the antenna will still be in the air. No difference in terms of wire overlap than when used at the ends of the dipole.

Over the years, I have used "egg" insulators in the center of dipoles many times. No problems at all.

The ceramic dog-bone insulator in the attached photo is at least 40-years old.

Glen, K9STH


92503

K1DNR
05-08-2012, 04:27 AM
If I'm going to BUY ready made insulators, whether from ePay or a retail dealer, I'd prefer true ceramic insulators. They do NOT degrade with weather or UV exposure, and are far, far better insulators (physically and electrically) than plastic. Under tension, wire will eventually "cut through" plastic insulators, leading to failure. Consider the voice of experience.
Most of the plastic insulators sold by Rat Shack and similar sources may be fine for a temporary (Field Day?) antenna (and we all know how temporary antennas tend to become permanent!) or SWL antennas with small gauge wire.

I have quite a few porcelain insulators myself.

The plastic ones I have are actually quite good, and even heavier/tougher than the MFJ porcelain insulators I have. Currently supporting the wire top hat on my 160m vertical which is made up of bare solid aluminum wire.

The suggestion was made because the operator was looking for household items. Unless he really likes cutting things up, its not worth his time.

That was the point.

Porcelain, or plastic he can buy them a lot cheaper than he can make them. I'd rather spend the time on a real project, or on the air. Not enough hours in the day to fool around making insulators.

WA7PRC
05-08-2012, 05:01 AM
... and even heavier/tougher than the MFJ porcelain insulators I have.

Daburn (http://www.daburn.com/10-73daburnairplaneinsulators.aspx) has been manufacturing them since dirt was new.

N8WWM
05-09-2012, 07:44 PM
PVC pipe works just fine. So does plexiglass. Save your money and take your lady to a movie and dinner.

A well attended to XYL or GF will view your radio fun with a lot less of a hairy eyeball if you make the time.
Or you can get her interested in radio...:)

KI4YIK
05-09-2012, 07:51 PM
PVC pipe works just fine. So does plexiglass. Save your money and take your lady to a movie and dinner.

A well attended to XYL or GF will view your radio fun with a lot less of a hairy eyeball if you make the time.
Or you can get her interested in radio...:)

Actually mine just got her Tech License :D KK4ITV

KK4AMP
05-09-2012, 08:32 PM
In the past some hams would use paraffin-saturated wooden dowels as insulators for ladder line and wire antennas. Hams would boil the dowels in the paraffin until the rods were well permeated.


I read this and it made me think of another hobby of mine. Drop some leather in that bath as well and you'll wind up with some cuir bouilli armor! Don't use this method on footgear though (http://anachronista.blogspot.com/2005/01/cursed-boots-of-pain-on-ebay.html)!

Back on subject, I got a nylon cutting board from the Dollar Store and plan on using that in bits for insulators.

W9GB
05-09-2012, 09:02 PM
Glass insulators for radio were also used
http://www.cyberbeach.net/~dknetzke/collection_glass_strains.htm

Corning Glass Works made Pyrex radio insulators at one time (through 1940s)
http://glassian.org/Pyrex/index.html
Wonder how much a Gorilla Glass insulator would cost today?

The Insulator Store - Check price of colored glass insulators
http://www.cyberbeach.net/~dknetzke/collection_glass_strains.htm

WA7PRC
05-09-2012, 09:58 PM
PVC pipe works just fine. So does plexiglass. Save your money and take your lady to a movie and dinner.
Porcelain insulators cost only a few dollars each. For the money saved, you'd be taking your lady to a matinee movie and then burgers at Mickey Dee's. The only impression you'll make is that you're a skinflint.
OTOH, you could pony-up for the best parts, and then take your lady to a lavish show and dinner. Live a little! :)

K1DNR
05-11-2012, 04:47 AM
Daburn (http://www.daburn.com/10-73daburnairplaneinsulators.aspx) has been manufacturing them since dirt was new.

Yeah, I have a whole collection from my Great Grandfather's tool factory.

W0AAT
05-11-2012, 09:16 AM
When I needed some insulators for the ends of my elevated radials I fired up the 60 watt laser cutter and made some 6 inch long from black acrylic. Nice toy to have :-)

K9STH
05-11-2012, 08:24 PM
There was an article in QST, possibly by "Nosey" KH6IJ, about amateur radio operators in Hawai'i using chop sticks for open wire feed line insulators. Probably because they were really cheap.

Glen, K9STH

WA7PRC
05-12-2012, 03:01 AM
When I needed some insulators for the ends of my elevated radials I fired up the 60 watt laser cutter and made some 6 inch long from black acrylic. Nice toy to have :-)
I used to work for the world's largest sealed CO2 Laser OEM. We had 'em up to 200W in a single tube and were close to getting a 400W unit into production when I left. Laser tag hurt and left a mark! ;)

W6OGC
05-12-2012, 06:59 PM
"Dog-bone" ceramic insulators have been available since at least the 1850s having been used in land line telegraphy.

Nothing wrong with using an "egg" at the center of a dipole. If, for some reason, the insulator fails the antenna will still be in the air. No difference in terms of wire overlap than when used at the ends of the dipole.

Over the years, I have used "egg" insulators in the center of dipoles many times. No problems at all.

The ceramic dog-bone insulator in the attached photo is at least 40-years old.

Glen, K9STH


92503

Funny coincidence.... I think my brother used to own that dollar.

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