Run back

Dr Doof · 19 March 2011, 11:20

Took this yesterday on the way back from the Farnes.

The A frame looks like its going to fall off! I'm sure it didn't move as much as that before I added the dome.

http://www.youtube.com/watch?v=

[YOUTUBE]VCzhxUDjwSs[/YOUTUBE]

Dr Doof · 19 March 2011, 11:23

Think this was taken on the way up to Farnes not the way back.

chewy · 19 March 2011, 12:09

It is wobbly alot that!

Dr Doof · 19 March 2011, 12:17

I know, hadn't noticed it moving like that before. Could be too much weight at the top?

chewy · 19 March 2011, 12:20

Weight up top won't help the tube itself doesn't look that big?

martini · 19 March 2011, 12:20

Quote:

Originally Posted by chewy

It is wobbly alot that!

That is quite scary, can't see the s/s putting up with that for long before it work hardens and breaks

I know of another rib with a similar design, frame curves round the tube and then up, he has problems with welds breaking etc. What diameter is that tube? No doubt the wall thickness is measured in thou

kerny · 19 March 2011, 13:05

Perhaps some extra brackets fitting the A frame to to the transome might help.

chewy · 19 March 2011, 13:10

Haven't a few Humbers suffered this problem?

Dr Doof · 19 March 2011, 14:56

The tube is around 2". I'm going to have to do something with it.

Yesterday's trip out was just over 70nm. I'm a bit nervous of doing that kind of distance with the A frame moving around so much.

martini · 19 March 2011, 16:29

2" is good if the wall thickness is reasonable, I think it's more the design. A more direct transfer of the load from the weight bolted to the top(radar etc) down to the deck/transom fixing points is preferred.

chewy · 19 March 2011, 17:07

Are the two lower bits that curve not braced between each other, its designed like a giant spring!

Dr Doof · 19 March 2011, 17:42

No brace at the bottom. The only brace is half way up the frame.

I think I must have over loaded it with radar.

chewy · 19 March 2011, 18:01

Quote:

Originally Posted by Dr Doof

No brace at the bottom. The only brace is half way up the frame.

I think I must have over loaded it with radar.

I think its reasonable to expect the A frame to be able to take the load of a radar though. It isn't helping matters having more weight up there but its bad design that is the route of the problem.

Dr Doof · 20 March 2011, 00:44

This one was taken a couple of weeks ago before I fitted the radar. It has some movement but not as much as yesterday. Makes me think too much weight at the top.

I thought it would be fine. I think you could be right about the design. Disappointing to say the least.

http://www.youtube.com/watch?v=

[YOUTUBE]EcKntrgEhhI[/YOUTUBE]

BruceB · 20 March 2011, 13:48

Is that the Humber double wide 1.5 inch frame and what sort of weight is the radar?
I was considering one of these with a radar reflector mounted on top but not if its going to do that!

Dr Doof · 20 March 2011, 15:02

Its a Humber A frame, I think the tube is around 2".

Weight of radar is 7.4kg. I'm not sure what to do with it now. The radar works really well and is very easy to install, set up and understand.

After watching the video I don't really feel comfortable with the A frame flexing like that. Sea state on Friday was slight. Wouldn't like to think what it would be like in moderate or rough.

I'm going to phone Humber tomorrow and see if they can suggest something.

chewy · 20 March 2011, 15:05

How old is the A frame, its not fit for purpose really so if you can I would get Humber to sort it.....

BruceB · 20 March 2011, 15:14

Humber make two versions of this frame, I saw the commercial 2" version on friday when at the factory. The one shown is not the 2" commercial one so must be the leisure 1.5" version.
Since the 1.5" version costs nearly 1k I wouldn't be happy at the way it is moving around in that video

Dr Doof · 20 March 2011, 15:16

I think it was fitted at the factory when new in 2003.

I have been thinking about replacing the RIB but not sure what I would go for. I like the way the humber feels sort of planted and never felt uncomfortable with its handling.

I'll see what Humber say tomorrow but just asking there advice as the frame is getting on a bit.

chewy · 20 March 2011, 15:17

I'd take it off stick it on flea bay and get a proper one knocked up.