Bertram 25 Top Cap modification

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ktm_2000
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Bertram 25 Top Cap modification

Post by ktm_2000 »

In my renovation I want to get more deck space. We've only stayed over on the boat 6 times in the 10+ years I've had the boat so the v-birth only needs to be there to house the porta-pottie. So I'm cutting down the area where the windshield used to be to make more deck space.

My plan is to put a large hatch and put in 2 large fish boxes under the deck where the drop-down used to be
https://photos.app.goo.gl/DxfoN7rmq9cawYgo6

My thought has been to keep the hard to fabricate parts of the bulkhead area (hatch frame, curved corners) and cut out the middle area and re-attach it. Last Friday I started cutting and here's a pic of what I chopped out. https://photos.app.goo.gl/2MVMfRK58fiD4W41A

I was planing on putting the piece back in and joining it
https://photos.app.goo.gl/EFXMJfuX63KvEWtu6

The gap in top cap material will come from a chunk of the drop-down which was cut out, I would glass all the pieces from the front side, then put several layers of glass in on the back side

Is there anything I am not thinking about?
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CamB25
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Re: Bertram 25 Top Cap modification

Post by CamB25 »

Are you relocating all of the electrical systems to the center console?
1963 Bertram 25
1973 Boston Whaler 13 - sold!
1998 Scout 172 SF - beach taxi
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ktm_2000
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Re: Bertram 25 Top Cap modification

Post by ktm_2000 »

Yes, main electrical panel would go in console.

I am curious where I am going to put my batteries. In the dual I/O days, I had 2 group 24 starting and 2 group 31 house batteries. I had a battery switch and multi-engine battery isolator setup to keep it all charged. The starting batteries were in the battery boxes just in front of the motors and the house batteries were in the base of the drop-down under the center console.

I removed the battery boxes under the deck to put in a larger fuel tank, I saved the piece that I cut out and was planning on glassing it back in, not sure if I want it in the transom area where the engines were or in front of the fuel tank.
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CamB25
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Re: Bertram 25 Top Cap modification

Post by CamB25 »

I went back and forth on battery placement and settled on putting the batteries under the helm seat, on deck. I didn't like the idea of batteries in the low point of the boat, or having to remove a deck hatch to access the switch. My third battery is up forward. It is used for the bow thruster only.

2 batteries will fit in the center section of the helm seat box with the long dimension fore and aft.

https://www.amazon.com/photos/share/ogZ ... oLy30pT2aq
1963 Bertram 25
1973 Boston Whaler 13 - sold!
1998 Scout 172 SF - beach taxi
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ktm_2000
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Re: Bertram 25 Top Cap modification

Post by ktm_2000 »

Cam,

All the pics I've seen of your boat, you've done an amazing amount of high quality work. My renovation definitely won't be done to your level of quality. I can wait to see the final outcome. I don't have your patience, If I were you I'd be driving myself crazy not being able to run the boat and probably cut too many corners and end up doing a poor job.

In the past I've made the mistakes (multiple times) of focusing on cosmetics and or electronics and hoped that the existing motor or motors would do ok for a while, each time I was pretty disappointed as I missed too much fishing time with engine problems. This time around, I am going to make sure all the non-pretty stuff such as stringers and under deck is done to a high level, buy a brand new motor and then run the boat. If it is everything I hope it is going to be, then I will work on making it look pretty. I'll probably be renovating the boat for many years but hopefully the renovations after this year are going to run april through mid june and I will get to use the boat for the summer.

On other boats I've always had 2 battery switches, one for the motor(s) and one for the house load.

I'm not opposed to having a battery under the deck, I just want to have easy access to it. I'm thinking of re-using the hatch which is in the base of the cabin. I am going to cut out 1/2 of it to make more deck space and it seems like it would be a decent size to be able to pull a battery through. I was thinking that the hatch could be right in front of the dog-house. From there, I could have a short run of cables to the house
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CamB25
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Re: Bertram 25 Top Cap modification

Post by CamB25 »

I was thinking about year 2...when you build the dog house/leaning post. You have a big project this year with the stringer/deck/cap/tank/engine plans. Might want to hold off on hatch work. Make a couple of plywood boxes for the batteries and strap them down somewhere aft.
1963 Bertram 25
1973 Boston Whaler 13 - sold!
1998 Scout 172 SF - beach taxi
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ktm_2000
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Re: Bertram 25 Top Cap modification

Post by ktm_2000 »

I am going to try and push off as much as possible to later years. My thoughts while the deck was opened up was to make the best use of the available space under the deck. If I were to reinforce stringer bonds first then put a flat panel across the lower center stringer and cross brace and box it in with bulkheads front and back it would make a good space for batteries

https://photos.app.goo.gl/5qQj5DSU7WePiBXS9

In the back of the boat, there's quite a bit of space where the motors used to be, I saved the battery boxes which I cut out and was thinking of glassing them in back of the cross brace. What I haven't looked at yet is if the battery box would interfere with the existing thru-hull location.

cut out piece
https://photos.app.goo.gl/xRokvmPdZsoog9W7A
old motor well
https://photos.app.goo.gl/Up5tdA1D8uCFJeUq5
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ktm_2000
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Re: Bertram 25 Top Cap modification

Post by ktm_2000 »

and the idea is pretty un-original, I got it from you....

Here's a pic I've saved in my archive, I think you might recognize it
https://photos.app.goo.gl/XPAqAFMBFw97Z2fz6

let me know if you don't want it posted online and I will take it down.
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CamB25
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Re: Bertram 25 Top Cap modification

Post by CamB25 »

I think I understand. On my boat, the OEM battery area is designated as "future fish box area". We installed the two bulkheads, but nothing else. No plans to use it right now, but I know where to cut.

On your boat, you extended the tank aft into the old battery area, so you are left with only the old bilge area to work with. It might get really tight in there if you try to install batteries, switch(es), 2 bilge pumps, thru hull, live well pump(s), wash down pump, transducer, etc.
1963 Bertram 25
1973 Boston Whaler 13 - sold!
1998 Scout 172 SF - beach taxi
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ktm_2000
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Re: Bertram 25 Top Cap modification

Post by ktm_2000 »

my kids went crazy last night so I didn't anything done after dinner....

but before that, I cut the rear-facing pieces of the cabin top down and started beveling the cabin top to be able to glass it all back together. I decided to concentrate on this area as the crack in my stringer extends under the cabin and I'd like to figure out the cabin top so I can cut away part of the v-birth area and fix the stringers. I haven't decided yet but think I am going shorten the piece 2" more thus I haven't beveled the edges yet. Hopefully I'll have time tonight to cut out a piece of 3/4 meranti to fit under whats left and extend out to support the piece while glassing the top.

top cap cut out
https://photos.app.goo.gl/xt1cuJvPcSz6ndvQ6

Piece temp held back in place (5" thick now, thinking of cutting to 3")
https://photos.app.goo.gl/2pbFdu3V3Xh5cLJWA

going to be interesting dealing with the sides to make it look good, might only end up with 1-2 layers of glass on front side and many more on back to make strong
https://photos.app.goo.gl/SxZz8LNEGDqYM3Dp7

My idea now is to use a piece of 2x4 and bolt it to the existing coaming and then bolt the piece I am adding back in to keep everything in alignment
https://photos.app.goo.gl/YFbL8v8Tt6ifF7Dn8
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ktm_2000
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Re: Bertram 25 Top Cap modification

Post by ktm_2000 »

worked on reattaching the cabin top today, I cut out pieces of 3/4" meranti to tie the 2 pieces together under the cabin top and test fit everything.
https://photos.app.goo.gl/GhH1VZyAK94pJqbD9

Piece of meranti tying the glass togther
https://photos.app.goo.gl/Uy4QJ73jCCp7UCnQ6

I'm trying to figure out what to do with the front of the hatch area, maybe put a board flat across the front and triangle pieces to tie it to the sloped front
https://photos.app.goo.gl/ZqKp6H94TnwbR3vN9

I'm kind of at a loss anyone have a good idea for this?

I probably should have planned this out more before I started cutting
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ktm_2000
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Re: Bertram 25 Top Cap modification

Post by ktm_2000 »

epoxy sealed the upper side of the plywood panel yesterday, glued it up today. While test fitting the pieces I couldn't get it to stay together with drywall screws because there is a fair curve in the cabin top. I ended up drilling some holes and using 1/4-20 bolts to hold it together.

https://photos.app.goo.gl/x66qvz3Tp4ct9ebH7

I'll probably use the same technique to hold the part tight when I attach it to the cabin.
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ktm_2000
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Re: Bertram 25 Top Cap modification

Post by ktm_2000 »

no pics tonight but I glued the pieces back on the cabin top. Needed 6 bolts per side to hold it all together tightly, even still the aft area hangs down if not supported. I clamped it up using a set of calls to align the pieces.
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ktm_2000
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Re: Bertram 25 Top Cap modification

Post by ktm_2000 »

After a week's vacation and multiple days of doing nothing due to rain I got working on the boat again last night. I unbolted the front pieces and stripped a couple of the bolts due to being over aggressive with the impact gun and epoxy on the threads which I ended up having to grind off the head of the bolt. The parts seem to be holding on their own and look decent. One thing with the 22" of shortening, the hatch is almost 2" less wide, it shouldn't be an issue but my nice doors which I built out of mahogany years ago might not be able to be cut down that much and still not expose the mortice and tennons, I didn't think of this in advance and will be an over the winter project to build some new doors if the old ones don't work.

I also started to get ready to fill the area left open by moving the bulkhead forward. I drilled holes in the top cap and used a chunk of left over 2x4 and used drywall screws to align things
https://photos.app.goo.gl/VLfneLsdvxarJ7G29

I also roughed out pieces which I cut from the drop-down section and test fit them. there's a bunch of prep work left before I can glass the pieces in, hopefully I can get that done tonight and glass.
https://photos.app.goo.gl/oggKYRdTL555HZYS8

I still need to figure out what to do with the front of the hatch, thinking of using the old front piece and figuring out some way to integrate it, here's a pic holding it up, notice the new opening fit inside the original rounded over corners of the hatch opening, any suggestions of what could be done?
https://photos.app.goo.gl/XEJvNiWE4G4ppoY88
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ktm_2000
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Re: Bertram 25 Top Cap modification

Post by ktm_2000 »

I've been slacking on the top cap for a while, there's been a lot of rain lately as well as getting dark early so I didn't do much. Last weekend the shrink-wrapper finally showed up and covered the boat so I have a pretty good workshop now. It rained pretty heavily late last night and I peaked in this morning and there was no trace of water.

Last night I glassed the cabin top, I put 2 layers of 1708 on the outside seams on the coaming and then covered the whole top of the cabin with 2 more layers of 1708. I'm going to let it cure for a couple of days, take the screws out which are holding the coaming pieces in alignment then put 4 layers of 1708 on the back side of the area which I filled in.

I also figured out how to deal with the front of the cabin hatch, I am going to use the original piece which was in front of the hatch, the issue being that it is now too wide since I moved everything forward I had to cut it down. I cut it in 1/2 at a random point then put the 2 pieces in the opening and put a mark where the 2 pieces overlapped, I then got out of the boat and put the 2 pieces on the chop saw and cut them at the same time so the cut would align. Well I screwed up and must have had another mark on the piece and the 2 pieces are too short. I have the scrap which I cut out and will put in a piece to fill the gap and put one layer of glass on the front and back side to hold it together then glass it into the boat.

port side coaming extension
https://photos.app.goo.gl/VB5ZgNez7CCH9oWC7

starboard side coaming extension
https://photos.app.goo.gl/Hj7bVZyWyLs3R9St6

Port cabin top
https://photos.app.goo.gl/acGStZJxubmdNEoB9

Starboard cabin top
https://photos.app.goo.gl/BFP1TptD4VT1fqw2A

Hatch opening
https://photos.app.goo.gl/2GLQq6A3xzxBxeK47
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CamB25
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Re: Bertram 25 Top Cap modification

Post by CamB25 »

Looks pretty reasonable! One trick I use is to fill the weave of the glass with thickened epoxy or epoxy fairing compound while it is still green (chemical bond). This saves lots of grinding time when you start to fair out the surfaces for finishes.

I never thought about using a shrink wrap tent. I was the king of tarp contraptions! Do you have an access door?

Cam
1963 Bertram 25
1973 Boston Whaler 13 - sold!
1998 Scout 172 SF - beach taxi
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ktm_2000
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Re: Bertram 25 Top Cap modification

Post by ktm_2000 »

yes, I have a door on the port side right after the back brace of the radar arch. I let the guy know that I needed to be able to slide in 4x8 sheet goods so he made it easy to work around, he did not shrink the transom plastic, the plastic was left long and folded over and extra straps were put in which I added clips to so they can easily be removed.

As is I can easily undo the transom area and slide it off to gain access to the full transom. I will have to mess with the 2x4 braces which are keeping the backbone supported but the screws were put in from the bottom so the pieces can be taken out fairly easily.

outside view
https://photos.app.goo.gl/3kLZEuCF7bg8igAv6
inside looking towards transom
https://photos.app.goo.gl/wDusx5xwzLiZgRZT8

I think the $330 for the shrink wrap is going to make a big difference for my project. I wouldn't have done the work last night without it as well as I expect 1.5-2 months more working time 1/2 fall- 1/2 spring because the wrap is like a greenhouse and a smaller area that I could potentially heat and do work later into the fall and earlier in the spring
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ktm_2000
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Re: Bertram 25 Top Cap modification

Post by ktm_2000 »

I will have to try your technique with the filler. I originally intended of putting a layer of 1.5oz mat on top but I did not think that I filled the trough I put in to join the 2 pieces well enough and thought that I'd need a blast of filler or more layers of glass to make flat so I didn't add the mat last night.

Also the coaming top was not quite flat and I wont mess with that until I get glass on the back side in case I have to grind through the 2 top layers that I put on last night to make it look right.
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CamB25
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Re: Bertram 25 Top Cap modification

Post by CamB25 »

I used 2oz cloth (not mat) when I finished the inner hull sides in an attempt bridge all of the heavy weave. Worked fairly well, but I still busted my backside fairing out all of the exposed areas. Many rounds of fill/sand before primers. It's work...no way around it.
1963 Bertram 25
1973 Boston Whaler 13 - sold!
1998 Scout 172 SF - beach taxi
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ktm_2000
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Re: Bertram 25 Top Cap modification

Post by ktm_2000 »

no pics on this one but I ground down the excess glass and used the left over filler from my transom work to put a first pass on the joints.
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ktm_2000
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Re: Bertram 25 Top Cap modification

Post by ktm_2000 »

I started working on the cabin bulkheads and ran into a self created problem. Since I shortened the cabin, the opening for the cabin is smaller and the door opening does not match the floor space opening.

I scribed the nida core panels to the hull sides and left myself @ 1/2" gap around the perimeter in order to not create a hard spot an made them fit the opening. As shown in the pic the opening to the cabin would be 20" wide which seems a bit too small for me so I am contemplating making the door opening the width of the cabin floor which is 24". I haven't figured out what I am going to do with the door frame, but I plan on tabbing the panels in with 1708 then putting a second layer of 1708 over everything then a layer of 1.5oz mat to fill in the weave and give me a good base to sand /fill. I got a 5 gallon kit of vinelyster resin for this as well as filling the weave of the inside of the hull sides. I plan on doing the deck the same way.

btw - the panels look like they don't match, this was the 1st panel I layed up in many years and I did in 1st side at 9am in the early morning sung and the resin kicked to fast. You can see the crappy side (port) and the 2nd side after I figured it out, to do the work in the shade. I wasn't thinking too well and forgot to flip over my 1/4" luan template so the sides don't look the same. The extra glass used to install will make up for my bad layup on 1/2 of the panel.

https://photos.app.goo.gl/Zs8seu7Z2zaPf4g89
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CamB25
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Re: Bertram 25 Top Cap modification

Post by CamB25 »

Self-Created Problem...another good boat name.

Hard Spots. I was very careful about how I installed bulkheads and other support structure to the hull sides. Guess what? They all print through to one extent or another. I think the only way to avoid (or minimize) is to tab in only, no glue in the gap.

What are your plans for using the cuddy? Storage only? camp outs?

Filling weave on inner hull sides. I sanded the woven roving as well as I could then filled the weave with thickened epoxy. When that started to kick, I laid 2 oz cloth over the panels. This gave me a reasonable starting point for filling and fairing. I would not use mat. Your not trying to build thickness. It sucks up too much resin. Can't fair it.
1963 Bertram 25
1973 Boston Whaler 13 - sold!
1998 Scout 172 SF - beach taxi
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ktm_2000
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Joined: Jul 17th, '18, 14:46
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Re: Bertram 25 Top Cap modification

Post by ktm_2000 »

Cam,

When putting the panels in, I was not going to do a fillet then glass over, I was just going to do 2 layers of 1708.

On the hull sides, what did you use to sand? I don't want to break up the existing woven roving but would like a good surface to bond to. I was thinking of hitting the outside surface with a DA and 40 grit pad then some type of rotating wire brush to start to get the depressions in the roving.

as for the cuddy cabin, I have twin girls + the wife so it really has to cover of 4 purposes. It is now too small for me to sleep in unless I slept sideways but would still work for my girls.
1. porta pottie
2. changing room
3. Rod Storage
4. Dry Storage
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CamB25
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Re: Bertram 25 Top Cap modification

Post by CamB25 »

It's just about impossible to sand all the nooks and crannies. I used every tool in the box and finally said it's close enough. The thickened resin and glass will bridge the depressions.

You could try applying a smooth fiberglass sheet https://cranecomposites.com/bp/sequentia.html I used this product to line my boxes, line the interior of the center console, and it forms the exterior of the molded fuel fill covers. Thought about it for the inner hull sides, but I didn't have any left in my shop and it would need to be vacuum bagged to conform to the hull sides.
1963 Bertram 25
1973 Boston Whaler 13 - sold!
1998 Scout 172 SF - beach taxi
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