Radar placement...again

[Patrick Turner]

Alright, I know this is been brought up befor, but I'm going to give it another shot since I'm budgeted for Radar insatallation next month. Is there any particular reason why I should not mount the radar on the backstay using the Questus or similar mount? Even though a majority of boats have the radar up on the mast, it just seems like having a radar that self-levels is a good thing. Sailing or motoring in fog when normally winds and seas are light is no problem for a rigid mount, but I'm really thinking more of when sailing at night for collision avoidance.

If there's any wind at all and your sailing to weather, Cape Dory's tend to flop right over to 15-20 degrees and stay. Well by my calculatios (splitting the 25 d. horiz. spread of the radar leaves you roughly 12d. either side of the center of the beam), you've practically lost most of one side of the radar's view....maybe both sides. Also, installation seems like it would be much easier on the backstay. Trying to fish the cable down the mast and then route the cable from the base of the mast back to the nav station or cockpit without seeing alot of junk is difficult I think. But stringing it through the cockpit lockers, through a bulkhead and along the shelves to the nav station is a cinch. Also, no chance of chafe on the stays'l or sheets getting caught up in it. I understand the concern about wear and tear on the cable if it's on a gimbal, but it seems to me that if the "loop" is fashioned correctly there should be practically no additional strain on the cable. And I don't think the aesthetics are a problem. Actually the lines of a CD kind of lend themselves to it.
So.....is there a particularlly good reason why I should place the mount on the mast rather then the backstay? It is more expensive, I know that.

Any and all comments would be appreciated.

Pat



patrick.t@attbi.com

[Ken Cave]

I have mine on the backstay, and it works great! It is easy to service as I do not have to climb the mast-and-with the swivel unit, I also works great at any angle the boat wants to do at any wind.

It costs more to mount it that way, but it is really worth it!


Ken Cave
Dragon Tale
Cape Dory 28



bcave@whidbey.net

[John R.]

Alright, I know this is been brought up befor, but I'm going to give it another shot since I'm budgeted for Radar insatallation next month. Is there any particular reason why I should not mount the radar on the backstay using the Questus or similar mount? Even though a majority of boats have the radar up on the mast, it just seems like having a radar that self-levels is a good thing. Sailing or motoring in fog when normally winds and seas are light is no problem for a rigid mount, but I'm really thinking more of when sailing at night for collision avoidance.

If there's any wind at all and your sailing to weather, Cape Dory's tend to flop right over to 15-20 degrees and stay. Well by my calculatios (splitting the 25 d. horiz. spread of the radar leaves you roughly 12d. either side of the center of the beam), you've practically lost most of one side of the radar's view....maybe both sides. Also, installation seems like it would be much easier on the backstay. Trying to fish the cable down the mast and then route the cable from the base of the mast back to the nav station or cockpit without seeing alot of junk is difficult I think. But stringing it through the cockpit lockers, through a bulkhead and along the shelves to the nav station is a cinch. Also, no chance of chafe on the stays'l or sheets getting caught up in it. I understand the concern about wear and tear on the cable if it's on a gimbal, but it seems to me that if the "loop" is fashioned correctly there should be practically no additional strain on the cable. And I don't think the aesthetics are a problem. Actually the lines of a CD kind of lend themselves to it.
So.....is there a particularlly good reason why I should place the mount on the mast rather then the backstay? It is more expensive, I know that.

Any and all comments would be appreciated.

Pat

You have pretty much covered the pros and cons. It's really just a matter of personal choice and needs. You now have a 36 and so it would at least look okay on the backstay as opposed to on the backstay of say a CD30. Mine is on the mast of our 30. Display is at the helm. Works fine mounted in that fashion for our needs. I would be quite concerned about cable flex with a backstay mount.

[Larry M]

Hi Pat,
I thhink the backstay would work fine but two additional thoughts, consider the beam angle and the effect on you in the cockpit and two the use of the backstay as a antenna for the ssb/ham. I think you can still use the backstay for the antenna but will need to place it above the radar.
Larry

Alright, I know this is been brought up befor, but I'm going to give it another shot since I'm budgeted for Radar insatallation next month. Is there any particular reason why I should not mount the radar on the backstay using the Questus or similar mount? Even though a majority of boats have the radar up on the mast, it just seems like having a radar that self-levels is a good thing. Sailing or motoring in fog when normally winds and seas are light is no problem for a rigid mount, but I'm really thinking more of when sailing at night for collision avoidance.

If there's any wind at all and your sailing to weather, Cape Dory's tend to flop right over to 15-20 degrees and stay. Well by my calculatios (splitting the 25 d. horiz. spread of the radar leaves you roughly 12d. either side of the center of the beam), you've practically lost most of one side of the radar's view....maybe both sides. Also, installation seems like it would be much easier on the backstay. Trying to fish the cable down the mast and then route the cable from the base of the mast back to the nav station or cockpit without seeing alot of junk is difficult I think. But stringing it through the cockpit lockers, through a bulkhead and along the shelves to the nav station is a cinch. Also, no chance of chafe on the stays'l or sheets getting caught up in it. I understand the concern about wear and tear on the cable if it's on a gimbal, but it seems to me that if the "loop" is fashioned correctly there should be practically no additional strain on the cable. And I don't think the aesthetics are a problem. Actually the lines of a CD kind of lend themselves to it.
So.....is there a particularlly good reason why I should place the mount on the mast rather then the backstay? It is more expensive, I know that.

Any and all comments would be appreciated.

Pat

[Matthew Atkinson]

Alright, I know this is been brought up befor, but I'm going to give it another shot since I'm budgeted for Radar insatallation next month. Is there any particular reason why I should not mount the radar on the backstay using the Questus or similar mount? Even though a majority of boats have the radar up on the mast, it just seems like having a radar that self-levels is a good thing. Sailing or motoring in fog when normally winds and seas are light is no problem for a rigid mount, but I'm really thinking more of when sailing at night for collision avoidance.

If there's any wind at all and your sailing to weather, Cape Dory's tend to flop right over to 15-20 degrees and stay. Well by my calculatios (splitting the 25 d. horiz. spread of the radar leaves you roughly 12d. either side of the center of the beam), you've practically lost most of one side of the radar's view....maybe both sides. Also, installation seems like it would be much easier on the backstay. Trying to fish the cable down the mast and then route the cable from the base of the mast back to the nav station or cockpit without seeing alot of junk is difficult I think. But stringing it through the cockpit lockers, through a bulkhead and along the shelves to the nav station is a cinch. Also, no chance of chafe on the stays'l or sheets getting caught up in it. I understand the concern about wear and tear on the cable if it's on a gimbal, but it seems to me that if the "loop" is fashioned correctly there should be practically no additional strain on the cable. And I don't think the aesthetics are a problem. Actually the lines of a CD kind of lend themselves to it.
So.....is there a particularlly good reason why I should place the mount on the mast rather then the backstay? It is more expensive, I know that.

Any and all comments would be appreciated.

Pat

I have a backstay mounted radar on a waltz leveling platform. It does not interfere with the insulated backstay ssb receiver since the backstay clamp is insulated. I do have a loop in the cable and some protective rigging tape, but there is no chafe to the cable anyway. The installation is no problem. Performance is much better on a leveling platform.
That being said, I met a single hander who who simply used a system of clamps on a pole mount to manually adjust the angle. He was sailing big distances (trans Atlantic) and found that the trim did not change so much that he had to play with the angle often. I think he was mainly interested in saving the money though.
No doubt it depends on your boat, but on my CD 30 C (1978), there is insufficient clearance from the main topping lift to have the radar mounted before the backstay, thus it is aft mounted. The mount is designed slightly off center, consequently there is constant torque as the radar wants to swing forward.
Perhaps it is no big deal, but in rough conditions I am always a bit nervous and set up my running backstays just in case, and I would be even more nervous without the runners.
There is no chafe on the backstay after several years cruising, nor any apparent damage to the rigging and I have been knocked about pretty much.
I have never run across a clear analysis of the hazards of backstay mounting, but the flexing and torque is obviously transmitted to the chain plate (where I don't see a significant problem) and the masthead, where I would just as soon not have it. Of course, the pole that runs up the backstay to support the aerial will not allow more than a little torque and it is fastened to a heavy stainless bracket on the deck - but the torque is absorbed by the backstay wire anyway - you wouldn't want rod rigging there.
Mast mounting I see as a bigger problem, especially on a cutter rig where it should be mounted above the detachable forestay. That is a lot of additional windage and weight high aloft - I read an article on the subject and in severe conditions it can easily make the difference in broaching. The physics are truely surprising.
I haven't read any analysis about pole mounting, but it may be the lesser of evils and I would consider it even though I have had no problems with the backstay mount - yet.

By the way, I used to have a good friend with your name that I lost track of years ago. If you are he, hello, if not, its a good name.



matkinson54@hotmail.com