Another alternative would be to use compression tubes between the two glass panels. Drill 1/4" holes thru the panels, cut some 3/8 or 1/2"OD/ 1/4" ID alum tubes of a length to fit between the glass panels, and bolt everything tightly to the tubes. Be sure that the tubes fit BETWEEN the two panels so everything will tighten up together. You'll still need access but not as much as it would take to put in backups, and no possibility of dry rot. Bridging the two panels solidly, as with compression tubes, would be plenty strong. -----Original Message----- From: John Schinnerer Sent: Tuesday, August 07, 2018 11:50 AM To: montgomery_boats@mailman.xmission.com Subject: Re: M_Boats: attaching transom ladder Just to add...because I re-did my motor mount backing plate recently... 3M 5200 is an adhesive as well as a sealer, so it may adhere the backing plate well enough to the transom. But you want to adhere the entire backing plate to the transom, so that it functionally becomes part of the transom in that area. If the edges and corners are not adhered then the part that is adhered will not flex, but the rest will. In other words, the transom will still flex wherever the backing plate is not fully secured to it. So you only get 'reinforcing' in the little square defined by the bolts and maybe some outside that where the adhesive is. The previous backing plate in my boat was just stuck in place with some sealant around the holes and bolted. The transom still flexed everywhere but in the small square formed by the bolts - the plywood was not attached anywhere else (also they used too thin of plywood) So whatever you use (I used thickened epoxy) I recommend coating the entire backing plate so that it adheres completely and becomes part of the transom. Mine is super solid now done that way. I can hang my weight on it (way more than any outboard I'd ever use!) with no apparent flexing (I used ~3/4" ply, epoxy coated). Also, round the corners of the plate so that whatever pressure on the transom is happening at the edges/corners does not get concentrated at one sharp point. FWIW the ladder that came on my boat has only large fender washers for backing on the inside. It is a 4-point mount however. I need to put a proper backing plate in for it, and I will do it the same way I re-did the motor mount. cheers, John On 08/07/2018 11:27 AM, Douglas Kelch wrote:
There is a technique for putting the interior backing plate in place without cutting large access ports.
I used 3/4 inch marine ply cut to the approximate shape based on the desired location on the outside of the transom. Drill the bolt holes aligned with the transom ladder, backing plate (while outside the hull) and the transom. Then enlarge the holes in the backing plate slightly to accommodate T nuts ( blind nuts) of the appropriate size. Install the T nuts on the backing plate.
Find two 8 ft lengths of reasonably stiff wire. I used house wiring, not striped. Run the wire from the outside of the hull through two of the opposite corner holes. You might hook a washer on the outside end so you don't pull the wire all the way into the inside. Go inside the cabin an capture the wire, then pull them through the corresponding holes in the backing plate with the T nuts on the bow side of the backing plate. Firmly attach a washer and a retrieval string to each wire. A diagram would show the sequence - string, washer, wire, T nut, backing plate, transom, washer. You can then trial fit the backing plate by pulling the backing plate to the interior of the transom using the wire. Check alignment of the holes by putting bolts through the transom into the T nuts on the two holes without the wire. If the holes don't align or the backing plate does not appear flush from what you can see through the holes, extract the backing plate using the string, (without tension on the wire the backing plate will fall down allowing the string sufficient friction to pull the plate back). Trim the backing plate for a better fit. Excess fiberglass near the top of the transom can cause a poor fit so do not try to get the backing plate all the way to the top of the inside transom.
If all fits well, lather the backing plate from the center to just past the T nuts with a thick sealant ( I used 3M 5200). Pull the backing plate into place using the wire and install two of the bolts for a snug fit, remove one wire using the string, install the bolt for a snug fit, remove the second wire using the string and install the 4 th bolt.
Tighten all up and let dry.
Thanks
Doug Kelch
Doug
On Tue, Aug 7, 2018 at 9:48 AM, Doug <doug9326@gmail.com> wrote:
I was thinking of running some bolts through the transom to the'interior'/ cockpit side of transom for more support. That way the is backing on the back side of transom as well as other side of transom, both with backing plates. The players could be made to look nice with team. What do you think of double backing plates built like you said.
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On Aug 7, 2018, 9:53 AM, at 9:53 AM, Dave Scobie <scoobscobie@gmail.com> wrote:
Doug:
For backing blates -
1/4" to 1/2" thick by 2"×3" for each of the mount's feet (those at the edge of the transom needing to be curved to follow the curve there). You want pad to be an one inch, at least, greater in size than the mount.
Coat pads with a couple coats epoxy.
Drill holes into tranom for mount.
Make a thickened batch of epoxy (moyo consistency) and butter transom side of pads. Press into place and creatively hold in place till the epoxy kicks (don't over-press and squeeze out all the epoxy).
Drill holes through backing plates using prior holes. Now is when you consider overrdrilling and filling and re-drilling to better protection of the ply if the bedding compound fails. Bevel the holes slightly on the exterior side.
Mount ladder with fender washers and lots if bedding compound (good amount of squeeze out) and don't over-tighten and squeeze out all the bedding compound.
Cleanup!
:: Dave Scobie :: M17 #375 SWEET PEA - m17-375.com :: SV SWALLOW - sv-swallow.com
On Tue, Aug 7, 2018, 8:22 AM Doug <doug9326@gmail.com> wrote:
My lockers are enclosed so a good size hole would have to be cut. If you have pics of your ladder attachment, I would love to see the backing plates.
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On Aug 6, 2018, 10:26 PM, at 10:26 PM, Lawrence Winiarski via montgomery_boats <montgomery_boats@mailman.xmission.com> wrote:
I had a couple of pieces of stainless bent for this purpose for the outside and inside of the transom. It's a job to get in there, but I could (barely) get the nuts on by reaching through the lockers...
From: doug <doug9326@gmail.com> To: For and about Montgomery Sailboats <montgomery_boats@mailman.xmission.com> Sent: Monday, August 6, 2018 9:05 PM Subject: M_Boats: attaching transom ladder
Just got a transom ladder for my M-15. Obviously the transom needs some help to support the weight on the ladder without it ripping the transom off the boat. So how is this done. It seems impossible to get inside the transom from inside the boat to add some sort of weight distribution plate on the inside. And what about the outside. Does anyone add a weight distributing piece of wood, brass, bronze, metal, carbon fiber on the outside to support the ladder weight when used? Just wondering how to proceed.
-- John Schinnerer - M.A., Whole Systems Design -------------------------------------------- - Eco-Living - Whole Systems Design Services People - Place - Learning - Integration john@eco-living.net - 510.982.1334 http://eco-living.net http://sociocracyconsulting.com