Trojan Boat Forum

hi guys, well its almost that time, and we are all waiting for the warm weather and the kick off of this season. At least those of us that are in the North,,
I bought a used radar system (raytheon R41 with a 42 inch scanner rotator) and I know I asked this question before, but I have a short memory,,,
I want to install the radar scanner, up over my flybridge, but I dont have a radar arch, ( I just cant spring for the 1500 bucks yet)
anybody have any thoughts on pole mounting this antenna, its the open array type. how important is it to have it unobstructed, etc, and is a pole mount do able
any thoughts would help without the result being thousands in a radar arch,
thanks in advance
Ive been working on the boat most of the winter, and am looking foward to a nice season,
I basically just spruced her up so shes clean and presentable, she has a long way to go to be what I would consider done. The goal was to do a nice cleanup , new head, curtains, paint cabinets, plumbing etc, and carpet,
mechanically she is fine,
I just want to thank all of you guys who have answered my never ending stupid questions, and hopefully can hook up with some of you this spring in the Hudson
thanks

In my opinion, you will need a radar arch or a hard top, or structure to mount it.

The 42" array is heavy and a pole or mast isn't gonna support it properly.
Some folks will mount a dome on the front below the bridge but an open array, how would you suspend it far enough out to clear it's rotation?
I have an 18" (24 mile) open array on mine and it's mounted on a plate which is part of aluminum my half tower.

I'd be looking at a used arch or waiting until I could buy one.

Good luck with your projects!

Bill,

Look at the replies from you last post on the subject.

Installation of radar on 31 flybridge cruiser

http://www.trojanboats.net/wforum/viewtopic.php?t=1502

Any obstruction in the radar beam will show up on the screen of the unit as an object. It will be a dead zone That’s why the antenna is mounted with a 360 degree view. You wouldn’t want the obstruction to be in front of the beam or it could block out something you were approaching. If it was behind the beam you wouldn’t see what was overtaking you. You also want to mount the antenna so it is raked forward, that way it's level when your on plane.

If you mount the antenna on a pole, it will have to be very well supported, and the pole would have to be strong. An open array antenna weighs about 20 pounds. The pole will have to be between 6’ & 7’ high to clear any obstructions. In rough seas there will be a lot of force due to the leverage.

You could use a 2 or 3” aluminum ridge electrical conduit to make the pole. A mounting plate for the antenna would have to be welded to it as well as a base. I offered my old mounting bracket from my old radar installation. If you extend the pole it will still need to be braced. If the bracket was mounted low on the front of the bridge, the extension pole could be braced back to the bridge, just under the windshield in each corner of the bridge. You would want to reinforce the mounting points inside the bridge. It wouldn’t look as good as an arch but it should do the job.

You could take your own advice from your last post.

guglielmo6160 wrote:

I think what Im gonna do is not use radar for a while, until I can buy an arch , I probably wont need it and I can put the money into other repairs that are more important
thanks for your responces
_________________
Bill Di Carlo
1971 F31' OUTTA CONTROL

"If you mount the antenna on a pole, it will have to be very well supported, and the pole would have to be strong. An open array antenna weighs about 20 pounds. The pole will have to be between 6’ & 7’ high to clear any obstructions. In rough seas there will be a lot of force due to the leverage. "

Gerry, you must be kidding...my Raytheon R21 24" open array weighs 59lbs.!

My estimate was conservative. It calls for another very.

What I should have written: If you mount the antenna on a pole, it will have to be very very well supported, and the pole would have to be strong.

yeah , its pretty clear I have to get a radar arch,, geeesh

I would not mount a open array on a pole , as the pole would have to be huge and need extra suport . My first boat with radar I buld a hard top to mount it on .

I built my radar arch out of 1 1/4" stainless and I wasn't sure that would be strong enough for that 60 pounder, however, I did add more braces as you can see by the picture. I have a Furuno 48 mi. open array scanner and it is HEA-VEY. I know, I put it up there by my self.

If I had it to do over again I would probably use smaller stainless tubing and a small dome type scanner, 5 lbs.

wowzer, can I ask you , how did you perform the bends in the arch, going along the top, did you use a manual tubing bender?

guglielmo6160 wrote:wowzer, can I ask you , how did you perform the bends in the arch, going along the top, did you use a manual tubing bender?

Here's a start to his build.

http://www.trojanboats.net/wforum/viewt ... radar+arch

well reluctantly I will put the radar install on the side for maybe next year, no way can I spend that kind of money on an arch right now,
thanks for all the advice,
I actually think I may manufacture one, like wowzer, his looks nice, and Im a pretty good welder, so I think I can make it happen, then maybe Ill get a smaller unit, that isnt so big and cumbersome

A wire feeder and tri-mix gas(helium, argon, carbon dioxide) for shielding works well with stainless wire. Any canvas shop will sell you some bent stainless tubing and some short scraps for the cross braces plus any fittings you want to use for attachment. You can over weld and then grind and polish the welds for a smooth custom look. This was the cheapest way I could find to get a strong enough arch that fits. If any of you decide to build one let me know and I'll help any way I can.

thanks will do,
maybe next year, this year is budget year,,,lol