24' DYI alloy remodel

Mods and custom builds
kmorin
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Re: 24' DYI alloy remodel

Post by kmorin » Tue Dec 08, 2015 11:55 am

Tfitz, I understand the helm construction much better now, and the insert carrying all the gauges and instruments looks like a nice way to solve the instrument mount issue, we used to mount them in metal, individually and it became somewhat of a headache to find spacing, get a balance to the layout and still have some structure left to the dash. Is that the cluster that came with the engine/boat or is this a new item?

The cable steering box (gear box so to speak) will mount under the circular base or on it? I've used cable steering before for outdrives when they had a power steering pump on the engine a cylinder on the outdrive and the cable mainly moved the valve position remotely; is the arrangement? or is the cable connected to the tiller arm of the outdrive directly? in the push/pull style cable?

Diamond tread is supposed to increase traction over a flat metal walking surface but in my experience it reduces traction in most cases. Sharp, new diamond embossed patterns (diamonds of metal) have an edge that will, for a while, grip rubber boots but that edge rounds off very fast as the tread plate is walked on. With a little sand and grit on the boots that becomes an hour or two! When the metal gets wet next, the traction is not high- it's lowered and the reason is that there's less edge to grip!... Now, the edges that gripped are rounded and they're just a reduction in grip of a boot on flat metal. And, if the boots get cold, the rubber gets harder, and the grip become more like walking on marbles compared to 'diamond tread grip plate'!

I've done some entire decks in this stuff, at the Skippers' insistence, and (heard) it was replaced because there were trips and falls on that deck, but the replacement deck with regular traction tape or paint, no slips, trips, and falls. The alloy I've seen is 6061 (not the 3000 series stuff for looks and tool boxes) and that is brittle by comparison to 5086 and cracks when bent incorrectly, which is far too often, so; hatch covers of tread plate will often work out to be a waste of time and have to be redone when the breakout at the corners or edges of 6061 leave the original hatch less than full strength.

Generally, I've found its worthless stuff in my work. If someone insists I use it: I'd insist they find another builder. I see a three slash pattern of diamonds on some material, not the single row by row version more common in most vendors in our area. I've not worked with this different pattern material and don't know how it lasts(?) but in general my experience is that aluminum as a whole material is not well treated to be rolled in raised embossed patterns with the idea those raised points will enhance traction.

Cheers,
Kevin Morin
Kenai, AK
kmorin

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Re: 24' DYI alloy remodel

Post by Tfitz » Tue Dec 08, 2015 3:27 pm

I don't have power steering it's just a cable that moves the outdrive. The instrument cluster is original

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Re: 24' DYI alloy remodel

Post by Tfitz » Wed Dec 09, 2015 2:08 am

I was a little worried that the steering wheel was going to be to close to the shift control arm but it turned out OK. I like it.
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Tfitz
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Re: 24' DYI alloy remodel

Post by Tfitz » Mon Dec 21, 2015 12:21 am

Well....what do you think? It sure opened things up. I'm still trying to get use to it. It's going to function well for making knee room when sitting in the seats and leg room when sleeping in the trunk cabin. I incorporated the defroster air duct into that 3" thick vertical colum supporting the port dash. It took me awhile to build that "artwork". I made it large to move lots of àir to possibly eliminate the need for a dash fan. Port side done and I just started on the starboard side. Cut the holes out is all. No fancy duct work starboard. It should go quicker.
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kmorin
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Re: 24' DYI alloy remodel

Post by kmorin » Tue Dec 22, 2015 9:46 pm

Tfitz, looks like the bunks will be less claustrophobic? Sure can see well into the fo'c'sle and that can make the space less confining. I'd have to see the seats with the knees to confirm your geometry but I can see where the room made by the cutouts will leave the helm area more comfortable. The milk crate seat on cutout look like your knees will fit into the bunk area and allow you to 'belly up' to the bulkhead?

The 3" duct for the defrost is not clear to me? Where is the heater element? In the bilge (under deck area) with engine coolant hoses running forward and aft? Then, is a fan pushing air behind a bilge mounted heater element- upward to the dash? May be too long a duct for air to push, typically pushing air is a pain in the stern except for reasonably short distances?

I recommend the DC muffin fans for cabin air movement (not talking about windscreen defrost/defog). If you have a diesel stove/cabin heater, those little DC surplus computer cooling fans in a small mounting frame are great to move the air, that will allow a radiating stove/heater to circulate heat around from the fo'c'sle to the bulkhead. They have so little current draw the batteries don't know they're there but they keep the entire cabin 'dew free' in our day boat down to winter temps. (not Fairbanks winter temps- PWS winter temps)

I'd like to whine a bit, (Harp ON): you need to practice welding more, the welds are
#1 too large, not proportional,
#2 too irregular, not uniform enough,
#3 not appropriate for their locations in the joints in the pictures.
(Harp OFF)

Lots of work in the cabin, as others here can attest, looking good, it will be interesting to see the cabin with the seats and replaced finish- not sure the level of finish you're planning? But, re-painting that nice blue dash will be a real challenge!!! (just kidding)

Merry Christmas to you and the crew, and all there in your neighborhood.

Cheers,
Kevin Morin
Kenai, AK
kmorin

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Re: 24' DYI alloy remodel

Post by Tfitz » Wed Dec 23, 2015 1:10 am

I'll say it slowl-e-y so you can read my lips. NO MORE PAINT! No blue paint..none...just when I thought my welds were looking pretty good I thought...I get slammed! Isn't wide welds stronger than narrow welds? I know they are far from perfect but they are strong and in my view not ugly. I'm just a guy who wants to go fishing in an alloy boat in the near future and I'm just trying to get R floating. At my pace (very little free time) the jobs ahead of me will take all winter and spring to do. I need to keep moving forward not practice welding.
This is kinda hard to explain but the last two photos shows the area below the port knee cut out area and at the base of the defroster duct. The square cut out hole you see below the floor is where the engine heated heater core mounts. It will have a two speed fan that will blow warm air into the "box" at the base of the defroster duct. Also I will have a separate diesel cabin heater that will be 4' away and have a 4" duct that will also blow hot air into this insulated box at the base of the defroster duct. So the box will be "pressurized" by these two fans and hot air will be forced up the 3"x 6" defroster duct onto the windshields. That "hot box" will also serve as a glove/sock / hat / food warming or whatever drying box. The guy who sold me the heater says they work great and other people who have them love it. So I'm in for one.
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Re: 24' DYI alloy remodel

Post by Tfitz » Wed Dec 30, 2015 1:54 am

I finally finished the dash and I'm pretty happy with the way it turned out, wide welds and all. At the cost of blocking a sliver of my forward view I installed two wireway/hand bars in the forward dash corners to give me a cable chase up to the future radar arch. Nothing installs easy with this project. Even the port lite instal turned into a time hog. The windows require a flat mounting surface and mine had a slight curve. I did a few minuets of dead blow hammer work and made it better but I still had to make a weld on, contoured spacer plate to give the port lite a flat surface to bolt and seal too. But I think the window spacers will add to the "lines" of the boat in a positive way. Guess I'll find out tomorrow after weld out.
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kmorin
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Re: 24' DYI alloy remodel

Post by kmorin » Wed Dec 30, 2015 12:18 pm

Tftiz, the hours are in the smaller details; we can hang a topsides sheet (half of the sides) in an hour or two with two or three guys and it takes days to fit the small details like port lights, dash panels, wiring races, and other small stuff. Rule of Thumb seems to be that a seam, almost any seam will take similar time. A chine is a huge seam and takes a day, maybe, but the seam in the shift throttle bracket takes a day too.

I've included a sketch of another way to do port lights, using a recess that converts the curved (hull) or truck cabin sides to flat, this set of sketches was from a discussion with a sail boat builder but it goes to show the level of effort in some of these seemingly small projects.

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Above, a concentric reducer is shown quartered into 4 corner pieces for the recess's edge flange.

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And here the quarters would be trimmed, depending on the radius of the reducer's two ends and body to give 4 conic sections.

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Here above, is the rough assembly of a recessed port light frame that will allow the wider/outer/flared out end to be trimmed to fit a curved trunk cabin or hull. All welds filled full and sanded flat and faired.

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Last sketch shows the green inner hull finish or liner (ceiling) where the flat inner surface meets the finish (likely place for finished bezel ring) and the outer hull is shown green and flat! I know this was supposed to be adapted to a curved surface but the drawing time was more so I got lazy and just put the flat outer hull panel to show what the resulting recess looked like.

Anyway, this method of recessing is used where the port light frame or 'window' may be recessed from both shape AND for weather. It does show the amount of work that can be involved in a single assembly as simple as adapting to a curved surface to seal a flat flanged port.

Sealing the new handrail/wire races at the top of the cabin is always a bit of a work out too. How do you plan to seal the wire coming down- regardless of size or number of conductors (radios, lights, radar, GPS....)?

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This water tight bulkhead fitting for cables ( to the right in the photo above, partly covered by the fuel and hydraulic steering lines) is one I make for this application but I don't seem to have any sketches handy. I'll dig them up and post so you'll have an idea of one method to seal individual cables/wires at the cabin top. This is a pipe thread stub welded to the deck. Inside is a narrow donut of aluminum about 2" down that holds a foam rubber 2" cylinder. That cylinder of foam rubber is drilled for each cable and slit from the outside of the cylinder so each cable can be slid into its own drilled/sized hole. Then the foam rubber cylinder is slid into the 2" pipe and a 2" plastic (ABS) thread cap with the end cut out is used as a compression gland so that when the cap is tightened down, the foam is compressed against the inside donut or retaining ring and the foam is squeezed onto the cables enough to seal tight. Just a shaft stuffing box concept adapted to a group of cables.

Takes a little more time but the joint is sealed by compression not glue or sealant and is easily removable to change cables; the biggest cable end fitting slides right through with not problem when adding or changing cables.

Cheers,
Kevin Morin
Kenai
kmorin

kmorin
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Re: 24' DYI alloy remodel

Post by kmorin » Wed Dec 30, 2015 12:54 pm

Tfitz, I did manage to find a set of images in my poorly organized archives of the compression seal cable bulkhead fitting.

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If you read my description in the previous post and look at this sketch shown, just above, I think the idea will be pretty clear?

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This cross sectional view was included in my past explanation as a way to make clear the inner ring of metal as the stop for the foam plug that seals to the wiring/cabling passing through the gland. (I realize I could have improved the drawing quite a bit by putting surfaces on the sectional view of all the components, but I was in a hurry, again, to get the drawing done and posted so it was left with this 'hollow' parts view.)

Hope these help your plans to provide cable seals at intersections of the races/hand rails and the cabin top? One boat had to go out before we could find any 2" deep foam so we took a floor mat of 5/8" foam the anti-fatigue mat that you'd use in the shop and cut a stack of 'foam washers' and drilled them all, slit them all and that gland sealed just fine. Sharpened EMT in 2' works perfect to punch out the rings, then other tube or a drill will cut the cables' openings pretty easily. Don't need to depend on single core of foam for this to seal. One of the guys who used this method also used a 1/4" layer of boiler gasket on top, (used gasket punches to cut openings) that rubber provided a tougher material than the foam on the top layer- but the older ones seem to be holding up just fine with various types of foam?

cheers,
Kevin Morin
Kenai
kmorin

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Re: 24' DYI alloy remodel

Post by kmorin » Wed Dec 30, 2015 1:17 pm

Tfitz,
I feel foolish for taking up all that space when all I had to say to you was- "use a CGB" to seal the cables! All that I've shown is a multi-path CGB. You can buy a half coupler- weld it to the deck and use plastic CGB's on both hand rails- depends on how many conductors as to size.

(forgot who I was talking with) :doh:

Cheers,
Kevin Morin
Kenai
kmorin

Tfitz
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Re: 24' DYI alloy remodel

Post by Tfitz » Thu Dec 31, 2015 1:45 am

Yea I have a 3/4 and 2ea 1" aluminum CGB's I got off some old equipment at work I was going to use but Ive got a different plan now. I was thinking of welding a short 180 deg 1" pipe stub penetrating the roof so the moisture would stay out by gravity. The wire way would act as a "hood" and wires would have a drip loop low point before going up into the 180 pipe going down penetrating the cabin. What I do kinda depends on what my radar arch looks like when I'm done too. I think a CGB stub would look crappy stubbed up on my roof. But I may do it that way. I'll just see how it goes. Radar power and signal, nav light, radio antenna cable, maybe switched power for a spot light, not much space really needed for the cabling going up top?
I only got one window welded in tonight. I took the time to weld the inside edge of the window opening then grind it smooth again. That should keep any moisture out from getting between the old cabin skin and the window patch covering the ugly seam. I know my welds are too wide and irregular in places but to me that's small stuff and I'm not sweating it. The only person I have to please is me. I'm all ears if you want to make any welding technique suggestions but practice isn't on my get it done list.
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Welded window opening edge
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Re: 24' DYI alloy remodel

Post by Tfitz » Thu Dec 31, 2015 2:11 am

Forgot to thank you for those beautiful cad drawings! Those are some very fine illustrations

kmorin
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Re: 24' DYI alloy remodel

Post by kmorin » Thu Dec 31, 2015 6:45 pm

Tfitz,

you're welcome for the sketches, I'd made them for other (years ago) discussions of a similar content.... had a couple of online back and forth(s) with others who were building in metal (some steel guys but I don't talk too much about the 'dark side' these days!) and once you get to talking metal work almost all boats have some similar issues to solve- not just port lights or cable seals- so I've got a bit of a library of my illustrations so when I have conversations about similar topics I try to reuse them - if the images address the current topic.

I've done both pipe and plate 'radar arches' sometimes called (Mediterranean Masts- shortened for a while to) 'med mast' where a frame that spans the cabin hold most or all of the electronics antennas. I could look them up if they're in your design future? Probably plenty examples on line?

cheers and Happy New Year

Kevin Morin
Kenai
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Re: 24' DYI alloy remodel

Post by Tfitz » Thu Dec 31, 2015 8:11 pm

I have plenty of used 1 1/2" pipe to work with (electrical buss) so that's what I plan to build my arch out of. I plan to keep it simple. Probably just two back to back bent pipes leaning into each other. I want to build it so quickly comes apart and swings down so at the end of season I can stick it under my shop overhang roof. I would like to see any ideas you have to build an arch. But I am 4 or 5 jobs away from doing the arch so that is at least a month or two away. The next job after the port light is a hand bar in the trunk cabin, then it's the seat pedestals, then the sink / stove fixture.

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Re: 24' DYI alloy remodel

Post by Tfitz » Sun Jan 10, 2016 12:40 am

The next job is my one and only cabinet fixture that will hold my two burner stove, sink, and two 6 gal water jugs. Also installing the cabin heater inside just off the floor. I'm thinking about building a drawer, maybe a cutting board and doors to access the bottom of the cabinet. I'm never real sure what I'm going to do until I start building it:) Kevin did you say you had some ideas / photos of some pipe radar arches?
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I got the starboard port lite installed. I think the welds came out a little better
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Installed hand rails inside the trunk cabin to make it easier moving on and off the bunks
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Built two seat pedestals. I decided to stick with the round smooth look that is similar to other areas of the boat
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I wanted the pedestals narrow at the top because both chairs swivel and will also be used facing towards the stern often. I wanted them wide at the bottom to match the opening in the under dash cutout.
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This is how I plan to sleep. Feet in the pedestal box. Doing this put my shoulders at a wide point in the bow area and lots of room for my head and gear toward the bow. When I sit up I'm looking out the port lite. The new trunk cabin hand rails make it easy to scoot over into this position
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Overall I'm pretty happy how it's turning out. I know this set up wouldn't be for everyone. But my priorities are using this boat as a "tool" to help me keep my freezer full of fish and game. More so than building a cushy, comfy set up

kmorin
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Re: 24' DYI alloy remodel

Post by kmorin » Sun Jan 10, 2016 1:18 am

Tfitz, wow!!! those seat pedestals are cool! I've never even thought of that shape, they work and look good, smooth and leave room for sleeping, as you show. The boat is on the small end of full cabin, I might have put four or five on the hull just to get some 'leg room' but you're compensating - nicely.

The port light cabin side doubler shows you're listening to my weld cautions even if you don't like it... and the weld uniformity is showing. Of course the welds on the trunk are 'gravy' and not the stand-on-your-head weld with the left hand welds that take so much effort inside the cabin. So you're not getting free of the 'weld harping'.

will you be planning to cover the insulation with some paneling/sheathing/covering? Or will you leave the foam bare? Not sure, you haven't said?

I'll find Med. Mast drawings if I have them? I may have some photos too? I'll dig and see, then post what I have, if not? I'll draw some that I've used in the past and post those.

Cheers,
Kevin Morin
Kenai, AK
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Re: 24' DYI alloy remodel

Post by Tfitz » Sun Jan 10, 2016 1:50 am

LOL :rotfl: I never would have guessed my pedestals were...in your view. "cool!" I thought my muscle car air scoop was "cool". But hey ...that makes me happy you like them :thumbsup: I want to keep this radar arch easy and ight weight. Think simple and 1 1/2" pipe. My neighbor and I were drinking a beer discussing the arch and I told him I was thinking a slightly leaning forward arch would kinda give it a "brow" look. He thought that was CRAZYness! He said the the pipe arch needs to lean back at the same angle as the windshield. He's probably right but I don't want it back too far towards the stern. I need to be able to tuck a dingy under it from the back side. In other words the raft will be at an angle, half resting on the offset up cab extension and it's bow tucked in under the arch

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Re: 24' DYI alloy remodel

Post by Tfitz » Sun Jan 10, 2016 2:12 am

Yes I plan to cover the foam / sides for sure but it will be the last thing on the list of jobs. I can always finish that next winter. I happen to already have 3 or 4 sheets of thin aluminum (not sure the gauge) it was free. I'm thinking I may make custom panels to fit the different areas of the walls. And on all sides of the thinned gauge AL panel cut outs I will fold the edge over facing in. That will be my edge or trim. Screw it down or pop rivet. And to keep it from tin canning I thought I would take some expanding foam and squirt some foam dots behind the panel just before I secure them in place. The foam would expand behind the panel and "firm up" the thin aluminum sheeting. I need to watch the pounds I'm adding to this boat though. Just those pedestals alone were 20lbs apiece. The boat was 4000lbs when I started and I'm really not sure how much more weight I've added

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Re: 24' DYI alloy remodel

Post by Tfitz » Tue Jan 19, 2016 1:33 am

My cabinet fixture has taken shape and now rigid enough for me to move it to my welding table to put the sides on it. At first I made it square but didn't like what it did to my isle way access. Chopping the corner completely changed the look and feel of the cabin. Way more user friendly and open now vs that square corner. I know it dosent sound like much of a change but it made a huge difference in the way I feel about it. I also made a box that recesses into the floor 7" deep that will hold the base of a 6 gal plastic water jug and keep the top of it under the first level of the cabinet. I thought it was such a efficient use of normally wasted space I made a second one for across the isle 7"x 22"x 10" wide. I need to find the smallest 2 burner compact propane camp stove to make this work. My sink space will be very limited. In fact I can't find a sink that will fit my space. But I think I have a solution. A steamer pan is about perfect fit for my limited space. I should have about a 9"x15" area for the sink, those steamer pans are about that size and 6" deep too. And about 1/10th the cost as a real sink but I would have to cut the drain hole. First ill get the stove then see what room is left for the sink
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Re: 24' DYI alloy remodel

Post by Tfitz » Sun Jan 31, 2016 6:11 pm

I finished the cabinet last night. With the help of my neighbor, it barely fit into the cabin through the back window. A 1/8" wider and It would have been a no go. The cardboard sitting on top of the cabinet will be the size of my sink. I'm getting the sink as big and deep as possible 17 x 15.5 x 7.5" deep. I like how the cabinet turned out. Continued the round smooth look. Honestly I would probably build things different if my welds looked perfect. But I don't have a TIG, and my MIG welds are far from perfect to look at so I will keep grinding away at the rounded, smooth look. Originally I planned to recess a two burner propane cook top into this cabinet but there just isn't enough room for that and a good sized sink. So I opted for the good sink and a two burner stove fold dôwn, portable stove. Ive been using a two burner Colman white gas stove for 15 years and it works fine so I will just keep using that system and set it up straddling the sink edge. Kevin, hope you havnt forgot about giving me a good direction to build the radar arch. I know as soon as I start it with out your input your harp will start playing the shouldaCouldaToldya blues
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Mounted a Planar 44D diesel cabin heater inside at the bottom of the cabinet

kmorin
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Re: 24' DYI alloy remodel

Post by kmorin » Sun Jan 31, 2016 7:39 pm

Tfitz, the cabinet looks pretty smooth, I can see the conflict in space stove vs stink, nice fiddle bar (combo fiddle railing and hand rail - grab bar) on the door side as you approach the cabinet. The reason most people TIG weld this sort of thing is just what you probably know- now. Finish takes time so if the welds are TIGged where finish is more often available in the first pass (?) then the next steps are reduced.

The cabin sure is tightly laid out, I notice the seat on the pedestal is right up close to the cabinet and the walkway is close by.... all volume is used.

I think the simplest way to discuss radar arches/antenna mounts is to show a few ideas I've used, not that they'd apply to your roof/cabin lines but there are couple that are easy to build, and maybe they'll inspire more design ideas on your part.

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This sketch is back a few pages on this thread somewhere, when you were discussing the raft/inflatable loading and all. I proposed using a pair of pipe bents that were trussed together as shown on the left here, above. I've done this on half a dozen boats over the years, using an angle fro the lower edge of both pipe ends to provide a long 'spreader' to weld to the cabin top. Because most of my cabins aren't for much load carrying- the angles are 18" or so long and one is welded to the top while the one welded to the pipe ends bolts to it... then by pulling all but the last bolt forward or aft, the entire frame will lay down. I don't show any webbing between two bents here, but I'm sure that's obvious to you.

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Above is another sketch that we discussed, at my suggestion of loading the raft over the a hard topped stern canopy, only shown here because of the idea of the raft fitting under the arch. I don't have the cabin roof line jog correctly in proportion here and I realize with the taller after portion in the way of my drawing this approach may not be the most effective raft stowage due partly to that taller after cabin top.

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I'm switching types of radar mounts now, above is a photo of single mast type with wings and a platform on top. This hollow mast is mounted almost to the cabin top brow (visor) and folds down for winter parking. Each pad holds some item of top rigging, antennas, radar dome, lights, GPS.... on an on.

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Above is a photo of the hinge line swing mock up to be sure the geometry of my shop designed quickie build would work?

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Photo of the boat ready to travel, antenna mast in service. It is possible to put two kayaks along side the cabin top , fit under the two arms and OR still snub the of the raft up to the base of the mast because its located so far forward. I'm not as happy with this look, the profile of an upright that far forward isn't in my style book, but the owner says it does what he had in mind when he decided that was where the mast should go.

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Box type or Mediterranean Masts are sometimes called radar arches, but this one is very low (skippers design choices) but is hollow so there are no lines/wires/cables/rigging visible except just under the given antenna, light or other hardwired equipment. But it shows the design elements of the box type arch. The swept sides, raked aft, curved inner and outer corners and the arcing (cambered) box beam cross element with (in this case) a aft raking forward face. The geometry is representative of countless hundreds of these most tall enough to work under, some with three or four radar domes and a forest of whip antennas.

There are the three more common types- but only representatives of their groups. Actually the first and third are the same in essence but the first does in pipe what the third does by way of plate and pipe segments to get a different look. Any of them will do the basic job of getting the electronics' radiators up to 'see' farther horizons and built of welded aluminum they'd lift and stow a raft too.

cheers,
Kevin Morin
Kenai, AK
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Re: 24' DYI alloy remodel

Post by Tfitz » Mon Feb 01, 2016 1:54 am

I see your view of a simple radar arch is way more complex that what I had in mind so I guess I'm on my own. I think I will use 1 1/2" pipe and go straight up and across from the most forward part of the cabin roof rail. Not leaning forward or aft and about 14" high. ( dingy tube diameter). Simple, light weight and functional. Two pipes, forward one straight up, aft one angled forward to stabilize. Guess I need to just build it and see how it turns out.

kmorin
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Re: 24' DYI alloy remodel

Post by kmorin » Mon Feb 01, 2016 11:30 am

Tfitz, couple notes on that idea of simple for the electronics mast and raft stowage.

First, there is almost always some harmonic vibration in the boat from the engine, (inboards much more so than outboards) for the life of me I can't predict what rpm range(s) but I've seen hand rails at the bow crack out at the base, good welds too. I've seen single stub up pipes on cabins break off, all good welds, and one or two other single legged verticals or near verticals crack at or neat their base from not having a two legged or braced (inverted Y) bottom. Can't say I'm all that engineering informed on this but I've seen it with single point pipes so I've gotten in the habit of adding the other 'leg'. With all that... short pipe stubs like 1" pipe that is 4-6" long with the GPS antenna on them don't seem to be a problem, I think the length of the pipe above is the key to the lever that makes problems for the welds and HAZ.

Just another point regarding 'simple'; if as design is so simple the base cracks out around the weld perimeter on you cabin roof, that's really complicated. Doublers are good practice with thinner material that will sustain a point load and vibrations with a vertical moment arm. So are padeye bases, where two padeyes are doing the 'lifting' or holding work, not sure why pipe seems to be more subject to vibration than flat bars or angles? but they do seem to be more subject to base line cracks than bars or angles and bars combined?

Will two vertical 14-18" verticals be subject to vibration cracking? I wish it was something I could predict? but I can't. However, since most of your brow, windscreen, roof transition and most other Profile View lines rake, the mast will not look very well unless you rake it as well.

Cheers,
Kevin Morin
Kenai, AK
kmorin

Tfitz
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Re: 24' DYI alloy remodel

Post by Tfitz » Mon Feb 01, 2016 3:55 pm

Ok Thank You for the comments. Your aft raking comment helps me figure out the design. I think I'm going to build arch pipes that are pinned and supported off the top rail. By pinned I mean a single bolt attachment that will allow the U shaped across the roof pipe arch to swing down to make the boat height less for winter storage. So imagine two U shaped pipes across the cabin top facing down, the forward pipe slightly raking aft and the second pipe leaning forward to support the first pipe. Both pipes tied together with a flat plate in the center that holds the radar and antenna ect. Both pipes pivot, so for winter storage, just pull the bolts on one side of the flat plate and both pipes can gently roll down. Leaving all wires and radar intact. Did you follow that?

kmorin
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Re: 24' DYI alloy remodel

Post by kmorin » Tue Feb 02, 2016 2:27 pm

Tfitz, yes that method of support is what I'd tried to describe a few posts up. The only issue we found was the two pipe bents being webbed together meant there was still some spread in the legs when the mast was tipped down. We ended up trying hinges, bolt on pads to attach webbing and various other schemes... still stuck up when the two pipes were welded to one another even when hinged down.

Looking forward to plans drawings, and sketches.. just kidding; pics of the final are what I'm really expecting.

Cheers,
Kevin Morin
Kenai, AK
kmorin

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