LM32 Cleat Backing Plate Installation
Dec 20, 2018 15:19:56 GMT
Post by chrismunson on Dec 20, 2018 15:19:56 GMT
Toe Rail Failure and Backing Plate Installation
The mounting of the 6 deck cleats on the top of the toe rail on the LM32 is a very poor design, and several boats have experienced the cleats being ripped out, with significant damage to the toe rail. The toe rail is filled with foam except for a small wood block at the cleat bolt location, this has very little strength. There is no backing plate on the cleat bolts, just washers. The wood is rotting as water has penetrated via the bolt holes due to the original sealant calcified into something resembling tooth tartar, and failing.
Under stress the cleat and mounting section of toe rail will be torn out. Stress cracks in the gelcoat at the cleat base indicate initial movement and weakness.
At the bow cleats, the underdeck access space is very constricted, making provision of a wide backing plate impossible. A 1 ½ x ¼ x 12-inch plate was installed.
The stern cleat bolts are very accessible and a large backing plate, consisting of a 1 ½ x 1 x 12-inch channel, ¼ inch think, is easily fitted that will provide the needed lateral resistance to the dock line pull. I did not address the midships cleats.
The repair Phase 1:
Materials:
www.Onlinemetals.com will cut to order:
2 Bow backing plates, 1 ½ x 8 x ¼ inch 6061 aluminum bar
2 Stern backing plates, 2 x 1 x 12 x ¼ inch 6061 aluminum channel
8 150mm x 12 stainless machine bolts
4 heavy stainless fender washers for bow cleats
1/8-inch rubber gasket material for underdeck bedding
Reuse the original 12mm nuts and washers
3M 4200 adhesive sealant (only 4200, not 5200 and not silicone.)
Procedure:
If the boat is on land, remove all 4 cleats, clean the mounting areas. You'll have to pound the bolts out from under the deck. At the bow, use a 12mm bolt as an extension to the bolts in place, using the nuts as a coupler, so you have something to smack. If the boat is in water, first remove, clean and use the stern cleats and bolts for the bow cleats, then do the stern. The sheet winches make fine temporary mooring bitts.
The old bolts will be fused in the cleats, use a heavy vise and mallet to pound them out, or a hydraulic press. Getting the bolts out is very hard.
Clean all calcified adhesive off the cleats, especially where the bolt head seats, or it won’t fit snug. An exacto chisel blade works well.
Use the cleats with bolts as drilling templates for the 4 backing plates. Check and measure in place before drilling oversize ½ inch holes in the plates. Cut rubber sheet pads the size of the plates to help seat them against the uneven deck underside.
Note: If the wood plug inside the toe rail is completely rotten, drill oversize holes and fill the entire void with fiberglass and resin, then drill for bolts. Otherwise, the hollow toe rail will be crushed when the bolts are tightened.
Bed the bolts in the cleats with 4200 under the head, create a ‘washer’ of sealant on the underside, and bed the cleat onto the toe rail, tapping the assembly into the toe rail slowly and carefully. On the LM32 bow, I had to saw away an 8-inch section of headliner that formed a flange that blocked access to fit the plate and nuts on the longer bolts. Don’t coat the entire bolt with 4200 you’ll make a horrible mess. Install the rubber pads and plates, and snug up the nuts, do not over-tighten, for at least 24 hours. The 4200 must set, so when pressure is applied it doesn’t all squeeze out and ruin the seal. Once set, install the pads, plates, washers and nuts, and crank tight.
Go to the pub.
Phase 2 – Additional Bow Cleat
The problem is bow backing plates can’t be made and fitted wide enough to provide resistance to the lateral pull or twist resulting from the dock line pull. And the toe rail has no structural value. I think the Phase 1 repair will suffice for the stern cleats, as the plate is large. For the bow, install a new large cleat on the foredeck behind the windlass to take the mooring strain. I used a Schaefer 10-inch aluminum cleat with a 4-bolt mount. hardware.schaefermarine.com/index.php?main_page=index&cPath=106_108
Make a large teak backing beam, sanded and sealed, to go under the deck, and butt against either side cabinet surface. Set the cleat on deck, thru-bolt to the beam, bonding all with epoxy paste. See the West System Fiberglass Repair Manual www.westsystem.com/instruction-manuals/ for working with a cored surface mount. Don’t just drill and mount, you must undercut the deck foam and fill the deck void with epoxy, then drill for the mounting bolts. Then just use the bow toe rail cleats as fair leads to the center cleat.
A couple of notes.
Don’t start this work in freezing weather.
If uncertain, have the yard do the work. Accessing and removing the bow cleat bolts is very difficult, and getting the old bolts out of the cleats is a job for a machine shop.
Don't put 4200 on the underside of the bolts. You want water to drip out of the connection so you know if there is still penetration, and can deal with it.
There is risk of major damage when the original toe rail connection fails, and it will. If you see gelcoat stress cracks at any cleat, its time to make the repair and protect your boat.
Overall the 4 cleat repair is 2 days work, another day for the new deck cleat.
The mounting of the 6 deck cleats on the top of the toe rail on the LM32 is a very poor design, and several boats have experienced the cleats being ripped out, with significant damage to the toe rail. The toe rail is filled with foam except for a small wood block at the cleat bolt location, this has very little strength. There is no backing plate on the cleat bolts, just washers. The wood is rotting as water has penetrated via the bolt holes due to the original sealant calcified into something resembling tooth tartar, and failing.
Under stress the cleat and mounting section of toe rail will be torn out. Stress cracks in the gelcoat at the cleat base indicate initial movement and weakness.
At the bow cleats, the underdeck access space is very constricted, making provision of a wide backing plate impossible. A 1 ½ x ¼ x 12-inch plate was installed.
The stern cleat bolts are very accessible and a large backing plate, consisting of a 1 ½ x 1 x 12-inch channel, ¼ inch think, is easily fitted that will provide the needed lateral resistance to the dock line pull. I did not address the midships cleats.
The repair Phase 1:
Materials:
www.Onlinemetals.com will cut to order:
2 Bow backing plates, 1 ½ x 8 x ¼ inch 6061 aluminum bar
2 Stern backing plates, 2 x 1 x 12 x ¼ inch 6061 aluminum channel
8 150mm x 12 stainless machine bolts
4 heavy stainless fender washers for bow cleats
1/8-inch rubber gasket material for underdeck bedding
Reuse the original 12mm nuts and washers
3M 4200 adhesive sealant (only 4200, not 5200 and not silicone.)
Procedure:
If the boat is on land, remove all 4 cleats, clean the mounting areas. You'll have to pound the bolts out from under the deck. At the bow, use a 12mm bolt as an extension to the bolts in place, using the nuts as a coupler, so you have something to smack. If the boat is in water, first remove, clean and use the stern cleats and bolts for the bow cleats, then do the stern. The sheet winches make fine temporary mooring bitts.
The old bolts will be fused in the cleats, use a heavy vise and mallet to pound them out, or a hydraulic press. Getting the bolts out is very hard.
Clean all calcified adhesive off the cleats, especially where the bolt head seats, or it won’t fit snug. An exacto chisel blade works well.
Use the cleats with bolts as drilling templates for the 4 backing plates. Check and measure in place before drilling oversize ½ inch holes in the plates. Cut rubber sheet pads the size of the plates to help seat them against the uneven deck underside.
Note: If the wood plug inside the toe rail is completely rotten, drill oversize holes and fill the entire void with fiberglass and resin, then drill for bolts. Otherwise, the hollow toe rail will be crushed when the bolts are tightened.
Bed the bolts in the cleats with 4200 under the head, create a ‘washer’ of sealant on the underside, and bed the cleat onto the toe rail, tapping the assembly into the toe rail slowly and carefully. On the LM32 bow, I had to saw away an 8-inch section of headliner that formed a flange that blocked access to fit the plate and nuts on the longer bolts. Don’t coat the entire bolt with 4200 you’ll make a horrible mess. Install the rubber pads and plates, and snug up the nuts, do not over-tighten, for at least 24 hours. The 4200 must set, so when pressure is applied it doesn’t all squeeze out and ruin the seal. Once set, install the pads, plates, washers and nuts, and crank tight.
Go to the pub.
Phase 2 – Additional Bow Cleat
The problem is bow backing plates can’t be made and fitted wide enough to provide resistance to the lateral pull or twist resulting from the dock line pull. And the toe rail has no structural value. I think the Phase 1 repair will suffice for the stern cleats, as the plate is large. For the bow, install a new large cleat on the foredeck behind the windlass to take the mooring strain. I used a Schaefer 10-inch aluminum cleat with a 4-bolt mount. hardware.schaefermarine.com/index.php?main_page=index&cPath=106_108
Make a large teak backing beam, sanded and sealed, to go under the deck, and butt against either side cabinet surface. Set the cleat on deck, thru-bolt to the beam, bonding all with epoxy paste. See the West System Fiberglass Repair Manual www.westsystem.com/instruction-manuals/ for working with a cored surface mount. Don’t just drill and mount, you must undercut the deck foam and fill the deck void with epoxy, then drill for the mounting bolts. Then just use the bow toe rail cleats as fair leads to the center cleat.
A couple of notes.
Don’t start this work in freezing weather.
If uncertain, have the yard do the work. Accessing and removing the bow cleat bolts is very difficult, and getting the old bolts out of the cleats is a job for a machine shop.
Don't put 4200 on the underside of the bolts. You want water to drip out of the connection so you know if there is still penetration, and can deal with it.
There is risk of major damage when the original toe rail connection fails, and it will. If you see gelcoat stress cracks at any cleat, its time to make the repair and protect your boat.
Overall the 4 cleat repair is 2 days work, another day for the new deck cleat.
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