glass bottom boat

DT · Post by DT » Wed Jan 29, 2003 10:03 am

I am thinking about doing a bit of glass work (maybe a 1 square foot piece of glass on the bottom of the boat) the boat is a D12. Since it is flat bottomed it doesn´t seem like it would be too hard. I was wondering how well epoxy bonds with glassplexiglass and has anyone ever done something like this? Thanks DT <IMG SRC="images/forum/icons/icon_biggrin.gif"> DT [ This message was edited by: DT on 29-01-2003 10:04 ]

Evan_Gatehouse · Post by **Evan_Gatehouse** » Wed Jan 29, 2003 11:00 am

You don´t want to use glass unless it´s tempered. It´s not strong enough otherwise. Use 3/8" thick plexiglass. Use a flexible adhesive/sealant, like 3m 5200 or Sikaflex 292. You need to coat all cutouts in the hull w. 2 coats of epoxy (of course). You should build a frame on the inside of the boat that will support the edge of the window and give the sealant a place to adhere. Something llike the picture attached. Evan Gatehouse

DT · Post by DT » Wed Jan 29, 2003 1:03 pm

Thank you for the quick reply <IMG SRC="images/forum/icons/icon_biggrin.gif">. I do not know where to get this sealer from, and I was wondering if this arrangement would work. I would probably put the glass under the seat.

DaveD · Post by **DaveD** » Wed Jan 29, 2003 1:53 pm

DT, As Evan shows the glass should be flush with bottom and push up against the frame which would be epoxied on the floor. Seal glass with "caulk" not epoxy. Wondering why you show two pieces of glass? Is the top piece "sacrificial" to take scratches and be replaced? I like the whole idea! Dave

DT · Post by DT » Thu Jan 30, 2003 7:44 am

DaveD I was originally think that the 2nd piece of glass would do what the frame did. Do you think that I should put the frame on the floor of the boat and on the bottom, or just the floor? BTW here are some links that I found in a search. www.kayakforum.com/cgi-bin/Building/ind ... BR> DT [ This message was edited by: DT on 30-01-2003 08:23 ]

Evan_Gatehouse · Post by **Evan_Gatehouse** » Thu Jan 30, 2003 11:30 am

NO! The glass sealant won´t be strong enough to keep the pane in place. The water pressure will be pushing up on the glass. A plywood frame, epoxied to the hull, will be strong enough. The sealant just keeps out the water, it isn´t providing a glue bond. You can get any of the caulkings I listed at a marine store - see www.westmarine.com for example. You can use 1/4" plexiglass, but it may bulge a bit - don´t go bigger than 12" square (and in fact, an oval or circular window would be better). Evan Gatehouse

Wayne · Post by **Wayne** » Tue Feb 04, 2003 11:44 pm

you can get the 3m 5200 at Walmart in the boating supplies section in sporting goods.

DT · Post by DT » Wed Feb 05, 2003 11:55 am

Thanks for all of the replies, I found the 14 inch plexi at Home Depot, I also found the marine caulkadhesive there. David Tucker

VD · Post by VD » Fri Feb 07, 2003 1:06 am

Cell-cast acrylic would be better. It doesn´t bend as much as regular plexiglass does. This cell-cast material is the same type they use to make aquariums in stead of glass. -vd-

Wayne · Post by **Wayne** » Fri Feb 07, 2003 3:07 pm

www.duckworksmagazine.com will be running an article on building glass bottom windows in boats in the next couple of days.

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