Thickness of balsa core in Mark 1 coachroof?

luigisante · Post by **luigisante** » Tue May 31, 2011 12:41 pm

Anybody know how thick the balsa core is in the coachroof? I need to route out enough space to put 2 mounting points on the port side to service the folding bunks I'm building. Also, while I have your attention, anybody know of a small drill depth limiter that you can put on a hand drill to keep it from drilling anything deeper than a set depth? I'm using tape at the moment to let me know the depth but it's not great.

Lou

Fatboyfinn · Post by **Fatboyfinn** » Tue May 31, 2011 1:49 pm

At the moment I'm the payed grunt building a 32 foot balsa cored cat and we cut an oversized holes in one side
of the sandwich ( I did from the inside ) with a hole saw - say 20mm - and fill with epoxy bog and then put a patch of glass over the hole
then redrill thereby sealing in the balsa - does that make sense? I have recently refitted the internal hand rails and did this in my Telstar mk2.
I also drilled the handrail holes oversized and filled them with epoxy and tapped them M6. If you have a mo check out the Gougeon book on
wood epoxy techniques - brilliant.

And I think the balsa was about 1/2

Andy

JoeWalling · Post by **JoeWalling** » Tue May 31, 2011 2:14 pm

Hi Lou

Don't know aout the bals core thickness but I'm really looking forward to seeing what you do with the bunks.

Over here we have drill spacers designed exactly for the purpose you seek. They look a bit like the rubber washers you can buy to fix a leaky bathroom tap ( faucets I believe you call them), so you could try one of those.

Joe

Dan · Post by **Dan** » Wed Jun 01, 2011 2:16 am

Likely the core is 1/2". As for a drill depth limiter, you can try this. Google "drill stop" if you want more choices.

luigisante wrote:Anybody know how thick the balsa core is in the coachroof? I need to route out enough space to put 2 mounting points on the port side to service the folding bunks I'm building. Also, while I have your attention, anybody know of a small drill depth limiter that you can put on a hand drill to keep it from drilling anything deeper than a set depth? I'm using tape at the moment to let me know the depth but it's not great.

Lou

luigisante · Post by **luigisante** » Wed Jun 01, 2011 9:36 am

Thanks Dan. That was exactly what i was looking for. I have a basic design for the port bunkbeds. As soon as I can finish up the port electrical panel, I will carpet the space under the cockpit and then, I am ready to make the setee and bunks. I had originally planned on making a frame and skinning it with 1/4" veneer plywood and foam core. But, I think a 1/2" piece of plywood would suffice with a ladder frame built on the underside. I would think that the weight would be the same as or lighter than an epoxy/foam core setee. So, I'm just going to make the bottom and back out of 1/2" birch plywood with a ladder frame underneath. I am going to hinge the top bunk all along the rail on that is mounted on the port window shelf edge and add a backer on the inside to strengthen the assembly. The setee back will fold up and cantelever on the shelf edge.

Here is my rough sketch of the top bunk.

bedplan.jpg (16.08 KiB) Viewed 23 times

Lou

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