Page 1 of 1

bow light mounting bracket

PostPosted: Sat Sep 18, 2010 2:34 pm
by skier
Constructed a two-piece stainless bracket to hold a bow light.
Pics here:
http://picasaweb.google.com/xcskier.borg/BoatBowLight?authkey=Gv1sRgCJrfg_22pIHf8QE&feat=directlink

PostPosted: Mon Sep 20, 2010 7:10 pm
by talbot
Nice. I was just contemplating going in from underneath and inserting the metric light attachment bolt from inside. This looks easier. and quite professional.

PostPosted: Tue Nov 08, 2011 11:36 pm
by superfly
I am interested in mounting portable led running lights on my boat, and would like to know where you purchased the materials to make the two-piece stainless bracket?

PostPosted: Wed Nov 09, 2011 1:41 am
by GreenLake
Looks like a nice and sturdy design, especially for those who are handy working with metal.

When I built a support bracket for the bow lights for my boats, I wanted to not have to drill into the boat at all. I designed a bracket that just slips on and is secured with a short strap of bungee cord. Despite the fact that it isn't screwed on, it's been quite secure (well, I haven't really tested it in winds higher than 15 kts, or waves higher than 1-2ft).

Just for comparison, the description is here.

The materials I used were oak scraps and epoxy (and one machine bolt - which I left out of the drawings unaccountably). However, it should be possible to realize a similar design in metal.

PostPosted: Wed Nov 09, 2011 12:56 pm
by Alan
Jeff,

Last time I tried to drill stainless, it didn't work at all, so I raced out and bought some cobalt bits, which I haven't had the chance to try yet. Got a recommendation for bit type and drilling method?

Superfly,

You can order stainless flat bar stock from www.onlinemetals.com or www.metalbytheinch.com

PostPosted: Wed Nov 09, 2011 1:54 pm
by GreenLake
Low speed. High pressure. Lubrication. Sharp bits.

Those are the four mantras that crop up in every discussion of stainless steel drilling. SS hardens as you try to cut it. If you attempt to drill but fail, the claim is you could locally harden your piece to where you can't drill it even with proper technique.

The same reason is given for why drills break when exiting on the other side of the SS piece. Going slow is supposed to help.

It seems a solid clamp and drill press would be essential for good results. When I've tried to drill out SS screws in place, for example, I've failed spectacularly, because getting the conditions right with a battery powered drill operated freehand isn't easy.

PostPosted: Wed Nov 09, 2011 2:02 pm
by GreenLake
Oh, and you need lots of moral support. This guy shows how to do it, and he has the right help.

http://youtu.be/De3dL321XEE

PostPosted: Wed Nov 09, 2011 2:23 pm
by talbot
The type of drill bit makes a difference, too. You need one designed for stainless. Can't recall the alloy, but the price tag will give it away. Spendy, and they end up pretty dull after working through 1/8" of hard metal.

BTW, last season I followed the earlier suggestion of going up through the deck from below (via the forward bulkhead access port originally put in to replace the bow eye). I tried a vertical mount using the end of the light. Attaches OK, but the viewing angles aren't even close to legal. (A vessel approaching from astern might be able to see the bow lights, and would not be able to tell whether you're coming or going.)

Last night I hacked off one leg of the aluminum clamp-on bracket that came with the light, screwed the light to the bracket fragment, and attached the bracket to the deck screw with a wing nut. I was trying for the same effect as the stainless bracket, and it seems to work. Plus the metals AquaSignal uses are butter-soft. Definitely no need for hardened bits.

PostPosted: Thu Nov 10, 2011 3:55 am
by djd
Could try type 303 stainless steel. Corrosion resistance similar to the more common 304 or 316 stainless, but easier to machine.

Here is a link to McMaster Carr's web site:
http://www.mcmaster.com/#standard-stain ... ts/=evb5ab

I'd also consider Delrin plastic. Good strength, water resistant, machines like aluminum.

Dennis