“A” frame help

[allena]

Hi, newby looking for some advice, I recently purchased a ribeye ta480 (Aluminium) without an A frame and want to install VHF radio but have nowhere to put aerial. I have looked at the folding options available through ebay ECT but am a bit spectacle; I also have height limitations due to the boat being stored in a garage. So in summary I think I am looking for a bespoke one made in the Christchurch / Lymington area. Alternative suggestions or recommendations as to local company that could make this would be appreciated.
Thanks

[Pikey Dave]

Originally Posted by allena

Hi, newby looking for some advice,,,,,,,,,,,, am a bit spectacle;,,,,,,,,,,,,,, I also have height limitations

I think this bloke had a similar problem. Welcome to Ribnet

[allena]

Not quite the highly technical response I was looking for but the welcom appreasiated

[9D280]

Allena, Welcome!

I'm not going to be much use for the Lymington area, but if it's just a VHF aeriel you want to mount, could you install a pole?

That way you could have a couple of hoops or a tube with a couple of brackets welded to it , and either live with the cable needing fed trhough the mount or cut an exit hole / cable calamp above the mount. Then a simple small eye bolt / nut and a bit of bungee to sto pit working up & out as you bounce along. an eye bolt / nut on one of the top mount brackets & a bit of shock cord & a stainless hook -job done.

Avon were advertising an "imminently going to be available" removable light / antenna pole. Might be worth a look?

[Ian M]

Without knowing the layout of your boat it is difficult to be precise. There are a number of ways you could tackle this. I have seen console mounted VHF antennas, I have also seen them mounted on a stainless screen surrouond. In my view neither of these are great solutions for a number of reasons, not least safety. You could go for a single transom mounted pole on which the antena is mounted. I know that Hightower has a solution similar to this. Do a search on here.
Making a folding or detachable mount should not be a great challenge.
However, I am not aware of a ready made solution that you would be able to buy over the counter without some sort of modification. You could try BHG in Lymington who fit out RIBs, but it is probably best for you to decide what you want and then get it fabricated. Stainless Steve in Lymington is a good guy for stainless fabrications.
And welcome to Ribnet

[Tim M]

If I were in your position, I would fit one of these to the console:

MARINE VHF Radio Stubby Antenna for RIB / FISHING BOAT or Emergency. NEW | eBay

If however you specifically want an aframe because it looks cool, then I would suggest one of these (they will produce one at any width if you ask):

Top Quality 316 Stainless Steel Seat A Frame Radar Arch Boat RIB NEW | eBay

Given the cost involved I'd probably go with the first option! If you're just using it in the Solent I wouldn't worry about lack of height in terms of loosing too much range - you can get hold of Solent coastguard just about anywhere using a hand held!

PS. I personally would steer clear of the cheap ebay folding ones - I don't think they'd last five minutes.

[allena]

Overwealmed with the response THANK YOU
Sirtainly got the old grey matter thinking regading the the pole on the transm idea, the concel dosn’t have any sutible fixing points, hand rails ect.
I think Tim M may have it right, an A frame does look COOL and would give storage for safty equipment( just selling it to my self) so I think my next step will be to track down Stainless Steve in Lymington.

Thanks again for all your help on this

[diverbert]

hy elena,

Thats a good idea, BUT please check out the material. If the hull and transom are of Aluminium and you make the A frame of Stainless Steel please note that there can be a potential difference (potentiaal verschil in dutch) between the two materials and it could well be that the hull is offering itself by corroding in a bloody fast way. So if you want to use Stainless please watch it and isolate it from the hull.
Or better use Aluminium tubing so you have no problem at all. You can use seawater resistant aluminium or normal al and powder coat it.

Hope to have helped you with this.

Just a dutch cheese head.

Regards
Bert

[jyasaki]

One of these on the transom:
Shakespeare Electronic Products Group - Ratchet Marine Antenna Mounts

and a 6' whip should do OK (that's what my buddy uses; mine is on the A-frame, but he doesn't have one.)

Allows you to lay the antenna down for storage and towing, but still get pretty decent range when on the water.

jky

[Ian M]

Originally Posted by diverbert

hy elena,

Thats a good idea, BUT please check out the material. If the hull and transom are of Aluminium and you make the A frame of Stainless Steel please note that there can be a potential difference (potentiaal verschil in dutch) between the two materials and it could well be that the hull is offering itself by corroding in a bloody fast way. So if you want to use Stainless please watch it and isolate it from the hull.
Or better use Aluminium tubing so you have no problem at all. You can use seawater resistant aluminium or normal al and powder coat it.

Hope to have helped you with this.

Just a dutch cheese head.

Regards
Bert

Bugger, missed that Aluminium hull. Yep, Bert has a point.

[allena]

Thanks Bert Looks like I will have to Wave goodbye to my shiny “A” frame
I like the idler of the ratchet mounted 6’ antenna but it sounds as though it may be more of a whip than antenna on a rib or are they more rigid than I imagined. Off to do some research on longer antennas.

[9D280]

My frame is ally.

....not shiny by any stretch of the imagination, but still made of Aluminium tube.

From memory there's a couple of reasonable close-ups in the "wake shot" thread if you want to see an aluminium one with 30 years' use behind it.

[diverbert]

no probs.
With an Aluminium Hull it's allways looking out what to do and it's ok to do some research. you have to watch out with the electricals to (connections to your antanna) Al. can be shiny to after bending and welding plish it and give it a cover of clear laquer?
Or use seawater resistant al. and polish it. will work to.

Thought i react before there is some damage u don't know where its coming from. And please post some pic's to

I myself have a SR5,4 and will be making a A-frame hopefully this year but first i want the boat ready and in the water. I'll be making a copy of an original Avon double A frame suited for a self righting bag (not mounting it)

regards.
bert

[martini]

Unless you use aluminium fixing bolts (not a good idea ) you will still have galvanic corrosion issues. But isolating a stainless a frame from the hull is easy enough, just use nylon backing pads/washers between the two.

Bolting through the floor is the tricky bit, all depends on access to the underside of the deck etc. Corrosion still shouldn't be much of an issue above the waterline anyway if there is small points of contact between dissimilar metals if they're maintained properly, Tefgel is good stuff especially on threads.

[allena]

Thanks mainly to the helpful people on ribnet that gave me the right questions to ask and a quick discussion with the man from Ribeye. The shiny "A" frame is back on the shopping list with the nylon plugs to isolate from the aluminium hull