Side rail clamp for a utility boat - canopy attachment?

[KC8QVO]

I am looking for a clamping device I can use as an attachment for a canopy upright on the side rails of a utility boat - an 80's equivalent to a lund wc-16.

The closest I can find to describe what Im looking for is a similar style clamp as what is used to attach a tonneau cover to a truck bed rail. The clamps are extruded aluminum, one end is rigid as a fulcrum, before that is a bolt for the clamping pressure, and the feet/pads are opposite of the fulcrum on the other side of the bolt.

Though, I would guess there is a purpose-specific clamp/attaching device for these style rails - such as attaching rod holders or down riggers.

Any ideas?

 

[Yacht Dr.]

Umm..vise grips? .. .. Ok Im kidding. But really..I have no clue what your talking about. Less laser pencil and more crayon please

 

[KC8QVO]

No Title

Here are some examples of tonneau cover clamps, there are a bunch of styles.

 

[Yacht Dr.]

Oh I knew what tonneau clamps looked like..I just cant really visualize what your trying to do. Are you trying to attach poles for a canopy/bimini to a vertical wall? If thats the case then they have side mounted stud type bimini mounts that would probably work..

 

[KC8QVO]

That is pretty much it. I want a clamp that I can use to attach the structure of the canopy to. The catch to it is I want to attach it with a clamp to the rail (top edging) on the top of the gunwales, I do not want to drill any holes to mount a bracket on the gunwales.

 

[Yacht Dr.]

Gotcha. Well..do you have any pics of where you want to mount to that you could post up? It would help a lot to see what your talking about. It would have to be a fairly beefy clamping system so it doesnt fly off lol..

 

[KC8QVO]

No Title

This is cropped from a larger image, sorry for the quality. I don't have a close-up of the side rail unfortunately.

 

[Yacht Dr.]

Cool..I see what your working with now.

I think the easiest way to do it would be to convert one of the side brace holes into a 'stud mount' for your main support pole. Basically put a through bolt in there with a little extra for an 'eye' end on your pole. The pole would have a 'Y' on it for a forward leaning bow about 2' up from the base. Then put straps going forward and aft on both sides. You could even put an eye on your transom corner guards and another set on your forward braces ( top holes ). So your not actually drilling any more holes per say.

If this does not appeal to you..then your right..you need some kind of C clamp type to hold on your bases. Other than small C clamps or welders vise grips nothing really comes to mind without making it yourself. If your gonna do that then you have your basic template from the teneau clamps..just modify the design a little out of whatever stock you plan on using.

Sorry I cant help more. But if something else comes to mind I'll let you know.

 

[KC8QVO]

In doing some research here a "gunnel clamp" is what Im after. There is a nice downrigger mount made by Walker called the Uni-Clamp. It has two screw bolts, though it is $70. Something similar, like the same style rod holder mount, I think is what Im after.

 

[Yacht Dr.]

Just wondering..why not convert your brackets to support a stud mounted pole? I mean..it would be less intrusive to do it that way instead of big ol' C-clamp rigs..

 

[KC8QVO]

If you are referring to "brackets" as the oar mounts then there are a couple reasons. The primary is I need flexibility with where the mounts go. The boat is a long way away from me. I took some rough dimensions as I went last time so I have something to work with, but I don't have the boat here to dial in the contraption precisely. I want to use the same mounting theory for a cross bar in front of the transom for mounting my downriggers too.