Adding a Bow Deck

[minuteman62-64]

Re: Adding a Bow Deck

There will be framing for the hatch. Only it will be attached to the underside of the deck, not the aluminum framing. I'll be using 3" strips of 5/8 plywood all around the hatch opening - 3/4" of these strips will extend into the opening and act as the lip for the hatch cover. You can see my thought process and the input I received here: http://forums.iboats.com/boat-resto...-hatch-cover-options-construction-635105.html

 

[minuteman62-64]

Re: Adding a Bow Deck

Did some fine tuning on the fit of the deck piece to the hull - a little work with belt sander, finishing up with planning down a few "high" spots and it set in nicely. Then did some measuring, to locate the positions of the framing members on the underside of the deck, figured where I'd want my hatch cutout, and drew it on the top surface.

I wanted to use the hatch cutout piece as the hatch cover, so I wanted as narrow a kerf as possible. Started looking for "thin-kerf" circular saw blades (about $30-$40) and then remembered my battery powered circular saw has a little less than 1/16" kerf. Worked great for the straight cuts. Used my jig saw with a smooth cut blade to cut the curves and there was my opening (attached photo). Cutout came out with just a couple of gouges (my stupidity) that will easily fill with some epoxy paste.

Good to see that the cutout portion of the MDO ply showed no voids. Appears to be good strong stuff.

Next step, frame up the opening - going to use some 5/8" ABX plywood left over from doing stern deck work. Attach to underside of deck piece with screws and epoxy.

 

[minuteman62-64]

Re: Adding a Bow Deck

Slowed down by pesky cold/sinus infection, now back to work. Framed hatch opening with 5/8" plywood. Because of size constraints (self imposed) couldn't make the framing cleats as wide as I was planning - but attached them with epoxy and a bunch of SS #12 screws to (hopefully) compensate.

Photos show framing on bottom, then set in place with and without cover. Screw heads will be covered with epoxy paste and sanded smooth. Cover is plenty stiff as is. However, I'm going to add some 1/2" plywood cleats on the bottom just for a little extra weight to help hold it in place.

Rather than attaching handles to the cover I'm going to go with finger holes (water tight is not an issue). One hole on the bow end of the cover will double as an opening for the anchor line - allowing the hatch to be in place while the anchor is displaced.

 

[kfa4303]

Re: Adding a Bow Deck

Lookin' good! I hope the hatch works out. I need to add one to my deck too, but I'm not quite sure of the layout. I've thought about a round, plastic porthole style hatch, but they seem to only come in fairly small diameters. Are you going to paint the decks, or cover them with vinyl/carpet, or something else?

 

[jbcurt00]

Re: Adding a Bow Deck

If you have some more 5/8" ply rips, I'd but a vertical rib on the underside of the deck, attached to your opening cleats & the deck. It is plenty rigid now, but after a season or 2 of use, and w/ the opening cut thru the deck, it could probably use some more support. Much easier now rather then later.

Nice job cutting the hatch & the deck ply looks like really good wood. I really like working w/ MDO.

 

[jigngrub]

Re: Adding a Bow Deck

Work looks good, but I'd avoid stepping on that hatch as much as possible.

 

[minuteman62-64]

Re: Adding a Bow Deck

Lookin' good! I hope the hatch works out. I need to add one to my deck too, but I'm not quite sure of the layout. I've thought about a round, plastic porthole style hatch, but they seem to only come in fairly small diameters. Are you going to paint the decks, or cover them with vinyl/carpet, or something else?

I was looking at the plastic hatches also, but the affordable ones were too small. Plus, by doing the trapezoidal shape I optimized the opening between the framing members.

This is not a casting deck. I'm not going to do anything that encourages people to stand on it other than when entering/exiting the boat. So, it will be painted to match the other seats, with a splatter finish.

 

[minuteman62-64]

Re: Adding a Bow Deck

If you have some more 5/8" ply rips, I'd but a vertical rib on the underside of the deck, attached to your opening cleats & the deck. It is plenty rigid now, but after a season or 2 of use, and w/ the opening cut thru the deck, it could probably use some more support. Much easier now rather then later.

Nice job cutting the hatch & the deck ply looks like really good wood. I really like working w/ MDO.

If you look at the photo of the framing in my Post #13, above you can see the framing members that border the hatch opening. The 5/8" cleats are 1/8" inboard of those framing members. So, I'm thinking that will give the deck proper enough support. I am a little concerned about the hatch cover - that's why I'm going to add some 1/2" reinforcing strips that will lie inboard of the support cleats.

I really like the MDO also. First time working with it. Half inch material with five plys, I've made about 20 ft. of cuts and have yet to find a void.

 

[minuteman62-64]

Re: Adding a Bow Deck

Work looks good, but I'd avoid stepping on that hatch as much as possible.

Concur. I do not plan to carpet or provide any type of covering that will encourage standing on it. The plan is that it will be used to mount/dismount from the trailer when launching/retrieving and partly as a seat, with the bow portion for stowing tackle boxes/lunches/etc.

 

[minuteman62-64]

Re: Adding a Bow Deck

Well, a step forward and a step and a half back. Decided to follow a suggestion from Woodonglass and use rare earth magnets for the hatch cover hold-down. Went to HF for their 10-pack and they were out. Not wanting to take another round trip to HF later in the week I stopped at Rockler on the way back and bought theirs. Big price difference - $2.99 at HF vs. 11.50 at Rockler. However, the Rockler ones were 3/8" in diameter compared to the 5/16" diameter ones at HF. Should be a little better gripping power per pair.

Not sure how many magnet pairs to use. The kayak guys say they should be 1/2" diameter, spaced every 3" around the hatch. Since I'm not planning on any Eskimo rolls, I'm thinking I can get by with fewer.

Started out with 2 pairs - one on each side. Carefully drilled 3/8" holes just a little deeper than the magnet disks. Wasn't confident of my ability to measure for alignment of the magnets on the cover and the frame, so I drilled 1/16" holes through the frame, taped the cover to the frame and drilled back through the holes into the cover. Then used a Forstner bit for the holes - drilling a little at a time. One over-drill I put some glass in the bottom to bring the magnet up to the level I was looking for. Encapsulated the magnets in epoxy and waited for it to dry.

Later that afternoon the epoxy was dry enough for a trial fit. Nothing! No grab felt at all. Seemed inconsistent with the grabbing power the magnets had when I was playing with them.

Oh well, try some more magnet pairs. This time added 3 more pairs - used up the last of my original purchase of 10. As I was mounting the new magnets I realized the dumb mistake I had made with the first pair.

I had carefully put pairs of magnets together and marked the surfaces (outside) that would be embedded in the hatch frame and cover. However, I removed the cover from the frame like you'd open a book. So, looking at the bottom of the cover, as it was positioned, the left side would mate with the right side of the frame. I had very carefully put one of the magnet pairs on the right side of the frame and the other on the right side of the cover. Net result: both magnets mounted with like poles facing.

Got the three new magnet pairs mounted (correctly this time), epoxy dried and gave it a test. Nice grab this time, even though the original two magnet pairs were pushing instead of pulling.

Photos below show my solution. Drilled around the two original magnets in the frame, using a hole saw and a little jig to stabilize it, made a plug with some well dried fir, split the plug in half and epoxied a piece over each of holes where the magnets had been removed.

Tried the hatch cover again with the two mis-aligned magnets removed. Even a stronger grab. I'm thinking that re-mounting the original two magnets in the frame and adding four additional magnet pairs will do it. I'll know tomorrow.

 

[64osby]

Re: Adding a Bow Deck

Reminds me of working with LED lights. Didn't mark the wires, a 50/50 chance. I seem to lose 75% of the time.

 

[minuteman62-64]

Re: Adding a Bow Deck

Magnet installation complete. I ended up using the remainder of the Rockler 3/8" magnets as well as some of the 5/16" ones I got at my local hardware store - worked out to almost one every three inches.

I don't know what the goal is, but I can almost lift the entire deck piece with the pull on the installed magnets. Good enough for now - If there's a problem when I get it on the water, with vibration/etc., I'll fill in the gaps with more magnets.

When I removed the two mis-aligned magnets I realized that their was very little adhesion of the epoxy to the magnet surfaces. The magnets are held in place by the epoxy "capsule" that surrounds them and bonds with the wood. So, the later magnet installations were modified. Instead of using a fairing thickener (West 406), as I did at first, I switched to a bonding thickener (West 410). I also over-drilled the holes (1/2" for the 3/8" magnets and 3/8" for the 5/16" magnets) to provide a little more epoxy "capsule."

Almost done. Just need to epoxy some braces to the bottom of the hatch cover, do some sanding, drill the mounting holes and start the finishing process.

 

[Woodonglass]

Re: Adding a Bow Deck

IMHO you've got way to many magnets and using to much epoxy. The REM's that I've used have a minimu of 10# pull and 4 of them will be more than powerful enuf to hold a hatch down. Coat the bottom of the magnet with some 5 minute epoxy and put it in place. For a Hatch Lid of approx. 12" x 18" in size, I'd use a 3/8" magnet in each corner of the lid and epoxy a 3/8" washer in the lip for the magnet to pull on. It would take quite a bit of force to get the lid to come off.

 

[minuteman62-64]

Re: Adding a Bow Deck

IMHO you've got way to many magnets and using to much epoxy. The REM's that I've used have a minimu of 10# pull and 4 of them will be more than powerful enuf to hold a hatch down. Coat the bottom of the magnet with some 5 minute epoxy and put it in place. For a Hatch Lid of approx. 12" x 18" in size, I'd use a 3/8" magnet in each corner of the lid and epoxy a 3/8" washer in the lip for the magnet to pull on. It would take quite a bit of force to get the lid to come off.

I was using info on one of the kayak sites as a guide - indicated that the magnet pairs shouldn't come into contact (apparently they are brittle and the nickel plating is kind of fragile) so advocated setting them slightly below the mating surfaces. My boat use will be strictly salt water so I wanted to protect the magnets as much as possible by epoxy encapsulation - so, lots of epoxy

The pull seems to drop off rapidly with a little separation. I've got each magnet buried about 1/32", so about 1/16" separation between the magnet pairs. I don't think I had 10 lbs. of total grab when I had just the four pairs in place. Now, with the 13 pairs, I've got about 25# pull (based on the estimated weight of the deck piece).

Oh well, wasn't all that expensive and my 70+ yo fingers can still pull the hatch cover off. Each surface will get a coat of epoxy resin and a couple of coats of paint in the finishing process - probably reduce the grab slightly more.

Regardless of my potential over-kill, use of the magnets was a great idea. Cheap, no projecting hardware, and effective. Appreciate the suggestion.

 

[Woodonglass]

Re: Adding a Bow Deck

Like they say..."What ever Float Yer Boat!!!!"

 

[minuteman62-64]

Re: Adding a Bow Deck

Moving on. Flooded deck and hatch pieces with CPES, then coated all plywood edges and all plywood surfaces surrounding the magnets with 105 resin.

Filled the 3" rise with pool noodles from Walmart for a little extra floatation (hey, can't hurt).

Next step - more sanding, then painting.

 

[minuteman62-64]

Re: Adding a Bow Deck

And, it's done. Actually finished painting 10 days ago - but, I know from experience with this paint that dry to the touch does not mean hard enough to withstand knocks/dings involved with installation. So, I let it cook for the ten days. Even then I put some past wax on the frame to avoid any paint "gluing".

Wasn't sure if I still needed the angle braces at the chines, with the raised seat. Just to be sure I cut the old ones down and installed them.

Photos show Before, Installed and Installed w/Anchor Deployed.

Soon as the ice flows in San Diego Bay melt off I'll take it out for a test run

 

[Woodonglass]

Re: Adding a Bow Deck

Ok, you get one of these...

 

[minuteman62-64]

Re: Adding a Bow Deck

Ok, you get one of these...

Thank you! I realize it's not much compared to the full bore resto jobs a lot of you guys do. But, it's all mine from cradle to grave

Just a brief testimonial to the 1/2" mdo plywood (that's mdo plywood, not mdf) used for the decking. Over 10 feet of cuts on a 4x8 sheet and not a void to be found.

Finally, for the non-believers/skeptics regarding standing on the deck. See below - that's 200 lbs. of speed, power and deception standing squarely on the hatch

 

[bear_69cuda]

Re: Adding a Bow Deck

Great job!

I went with 1/2" on my casting deck as well....