# Captive Skiff Build



## PropGunOne (May 27, 2018)

I’m going to start this thread off with a blank (for now) FAQ post. Anything that gets asked deep in the thread will end up edited back into this post, hopefully, so any questions will be right up front. FOr now what I post will be a duplicate of what’s on the blog at https://captive-skiffs.com. Eventually I’m sure it’ll diverge. Just getting something started for now.

The skiff, because of my foam-ordering skills, will be floorless, with gunnels instead of a tub. That means I’ll only be running fly rod tubes aft, but will still have room for four of them. Too much curve to the bow to run long tubes up the inside like that.

*THE FIRST THREE POSTS BELOW ARE COPY/PASTED FROM THE BLOG.*


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## PropGunOne (May 27, 2018)

*Materials….*


Get a bunch of questions about this. Materials, as always, depend on your skills, pre-planning, layout and choice of resins. I’m using a split resin setup, epoxy on the outer hull and top of the deck, polyester on all the inside surfaces. I originally did this for ease of tabbing in things like floors, bulkheads and stringers, the stringers which were also going to be molded from poly and 1.5oz CSM. Drying time, and the ability to adjust it based on MEKP ratios, was a huge plus. CSM is a resin hog, however, and between puttying the interior and matting it out I used in excess of two gallons, running out about the time I made it to the sponsons.

Based on where I’m at now, here’s what I’d recommend.

For an all-epoxy boat:

– 9 Gallons resin

– 6o yards 10 oz glass cloth (outer hull three layers below spray rail, two above. Inner hull two below and one above.

– Deck can be built in something lighter. I’ll be using 6oz because I have a bunch of it laying around, about 24 yards. 7oz would work as well. Use your discretion.

– Q-cells or glass bubbles. I’m using glass bubbles. Bought 5lbs, haven’t even gone through two yet

– For a non-bailing floor, seven sheets foam. Eight if you plan on adding it. This should give you enough to build your stringer out of foam core and simply glass it.



For a combo boat:

– 6 gal epoxy. Plan three to putty and glass outer hull. Rest is for fairing and glassing the upper side of the deck.

– 5 gal polyester. Like I said, CSM eats this shit. I’m losing weight savings here for sure but it makes the build easier and faster in my opinion. Not sure I’ll need all of this, but that’s what I’ve got on hand. Laminating resin is fine. I was worried about being left with a tacky surface due to the lack of wax but that doesn’t happen. I’m still not sure why that is.

– 36 yards 10oz glass, plus about 20yards of 6oz.

– 25 yards 1.5oz CSM

– Glass bubbles as above

– Foam as above



Paint: going with Pettit EZPoxy this time. I’ve used Jamestown’s WetEdge before and it did okay, but it isn’t bullet-proof. Two quarts hull, two quarts deck (different colors, could probably get away with 3 quarts total in all one color). One quart non-skid and a bottle of the performance enhancer. I’m not worried about not having enough.

I’ll be using West Systems ultralight fairing compound because… well… I have a bunch of it. Also got nervous/undecided and bought a half-sheet of 1/2” coosa board. I may use some in the aft-most bulkhead, level with the sponsons, to give me a surface to screw electrical parts to. I may not. Also useful for a trolling motor footing. $123 well spent.



My deck hardware is coming from AMarine. Used their Amazon-sold parts on my last build… three years with no issues on cleats, latches or hinges. 1/3 the price of anywhere else. All cast stainless.



I’ve got maybe $2000 in materials total, with a good amount of product probably not getting used. I’d guess you could get in one for 1600-1800 depending on your foam choice, possibly well under that in an all-poly, CarbonCore-based build. I’ll run those numbers later.

Layout is finalized. This skiff will be floorless, with an open rear bulkhead for wet storage. The bow deck will have a single large hatch with a small forward bulkhead filled with flotation foam. Aft sponsons will be foam filled. There will be under-gunnel storage for four fly rods, all of which I will have facing aft (I’ll explain the reason for this later). There will still be an elevated seat, but it will be sealed off from the rear bulkhead, essentially sitting atop the rear deck, and will be dry storage specifically sized for Plano size 3700 tackle boxes.


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## PropGunOne (May 27, 2018)

*HULL IN A WEEK*

Well… almost.

Credit unusually cold Georgia temps with jacking up my game plan. A skim coat slathered on last night wasn’t hard enoughto sand until 3 p.m. this afternoon. Even if it had been I’m not sure I would’ve gotten all the layers of glass on. More about that in a minute….

Oh, where have I been? Fixing houses, writing novels, carving fish, catching fish, killing deer, making beef jerky, building instruments, buying guitars… the usual. Oh, and also getting pissed off at the fact that the 200lb sculpture occupying space in my shed continued to go untouched. For 14 months.

Here’s what happened: the heinous GA climate wreaked havoc on our foam plug. I’ve seen the method used, had faith in it, but didn’t account for 40-50 degree weekly temperature swings. The MDF remained straight and aligned, but that was about it.

Fast forward to a few weeks ago. My real job, air traffic control, has been somewhat slow lately. In response to the whole Coronavirus thing we’ve gone to reduced staffing and a reduced schedule, trying to keep people away from people. The result is that I was looking at a lot of extra days off. I stained a deck, went to the lake, built a ukulele… all the while contemplating the foam-and-mud hulk out back. FIne, what the hell? $1500 later I had foam core and epoxy on the way.










Dented and rippled



I went with Carbon Core PVC foam. They offer several options, but the tech specs on this looked better than their PE or PU versions, despite being lower density (4lbs). I purchased eight sheets at $71.xx/sheet, plus about $145 shipping. CC charges an additional $45 non-commercial delivery fee. In retrospect I should’ve ordered an entire box of 24 sheets, paid the same shipping and had foam for three boats. I was getting concerned as I received no shipping confirmation from CC, but was pleasantly surprised to have the foam arrive three days after I ordered it. Faster than the sticky stuff.

Epoxy and glass came from RAKA, who I’ve used on all three of my builds. The prices are good, but they hide the shipping cost and charge you a ton later. While I like their products, this is probably the last time I’ll use them unless they update this policy and their website. Most likely I’ll go to US Composites.

Total materials so far:

Eight sheets H60 Carbon Core PVC

Six Gallons Raka Epoxy

36 yards 10oz glass cloth

12 yards 6ox glass cltoh

5 lbs 3M glass bubbles (thickener).



Got to work on Wednesday, 4/15/20. Returned from a short lake trip and took a hammer and angle grinder to the plug, knocking flat all the highs, vacuuming the detritus and creating one hell of a dust storm. Took 20 minutes. From there it was on to scribing chines, spray rails and the shear line. Started with the horizontal surfaces. If you’re good at scribing, this might be the way to go. I’m not. Doing it again I’d start with the shear line, oversize the spray rails and sand them to fit. My shear pieces ended up short and didn’t butt up to the spray rail edges, which is fine, but it meant more putty work later. While the 1/4” MDF was too thin to screw into, the sheetrock provided and excellent base for the… Sheetrock screws.














Onto day two: started cutting flat sections… keel where there was no V-entry, sponson bottoms and sides and the flat surfaces above (or below as pictured) the hard chine. Got that done, started cutting strips. I went with 2” increments and worked from the spray rail towards the keel, getting three rows done before calling it quits for the day.














Day three was all finishing of the forward strips and a flush sanding. Uneventful and went quickly. The bow, being plumb, either doesn’t come together great or I’m just bad at it. Who knows. That’s why Jesus invented glass bubbles.

Onto day four… how the hell to deal with this compound curve we created. Built to the plans, this part is relatively simple, the curve compresses, but only slightly. We shaped the inside curve on the CNC most like a section of nose cone off a rocket. We had reasons for this, mostly shiggles, but there should be some hydrodynamic benefits as well. We’ll see. Either way I struggled deciding how I wanted to proceed. I gave consideration to thermomolding, even building a wooden jig to test bends with, but ultimately went with good old strips – 3/4” or so.










Finished the sponsons, did some sanding. Puttied EVERYTHING. Nothing fancy here, just gooped thickened epoxy into the joints and used the curve on a spreader to smooth the fillets. Filled all the gaps between the planks, which were minimal, and started shaping the bow.



Day five began with putty sanding, about three hours worth. Maybe more, lost track of time. Got done, filled the remaining low spots, called it quits.

Day six… started contemplating hull/deck flanges. Again, this thing sits on a table top, not a strong back with minimal spots to accidentally glue things to. Permanent hull-to-table adhesion has been a concern, which is why you see the plug covered with parchment paper. Because of this, I was less than confident in my ability to get a traditional, PVC-molded flange in place without partially destroying it getting it off. Contemplated options over coffee, over a beer, over the NYT crossword puzzle… and decided on this:












1.5” foam strips. Generally flexible enough to conform to curves without help. Gorilla glued into place. For the sponson curves I took a heat gun to them, bending slowly as they warmed. Broke one, and two 8’ sections ended up being about 3” short, so I spliced in some pieces and boom… done. The strip will be glassed along its horizontal axis, trimmed flush with the vertical. The edge will later be filled with thickened epoxy. The deck will have a similarly dimensioned vertical overhang which will… uh… overhang the strip on the deck. Load the thing with bonding putty, slap the two together, round the edge and glass it shut.

At this point I realize I’m close to glass if I can just get a skim coat of epoxy on the foam and fillet the hull/flange groove. Accomplish all this at 10pm. Somewhere along the way I pattern fiberglass for the first laminate layer.



Day seven… overnight temps in the 40s, skim coat and fillet tacky. Turn on propane heater, take shed to 90 degrees. Pattern rest of fiberglass. The hull is getting three layers of 10oz glass below the spray rail, two above. Two layers are going to be segmented, in 3-4th lengths, overlapping. The below-the-rail layer is one long piece, plus some strips to cover what the 50” cloth won’t. 60” would’ve worked.

Check epoxy, still tacky. Try to sand, get worms. Drink a beer and wait.

Check epoxy. Repeat of above. Repeat previous actions.

Check epoxy… close enough. Sand for and hour. RO sander worn out, throwing discs like they owe it money. Revert to block sander and get the job did.










Glassed layer number one, working bow to stern. Took way longer than I thought it would, but went great. Couple loose threads, but no pooled epoxy, no bumps… nice, clean lamination. Chine radius a little tight, but it wrapped okay. Got done, totally sick of glassing. No way am I doing all three layers tonight. Drink a beer. Still light out. Aw, fuck it.

Glassed the long sheet next, wanting to trap it between segmented layers, figuring it would cut down on fairing. I’d read warnings from others about this being difficult over a tacky layer, but that was fine. I’d use it to pin the fabric in place and any folds I got would be easier to deal with than having to sand everything and wipe it down. Roll out went well, cloth looked flat, but the excess friction when I went to wet out prevented the cloth from TRULY flattening. Ended up with folds. Layer two is on though… just gonna require some sanding. Shouldn’t need any additional glass put in, just some high boogers and clipped-off folds. Lamination roller took care of the bubbles. I probably wouldn’t do this again. Finish at 9:30pm, one week and six hours after I began. One layer of glass shy of a floatable hull.

One week… after 14 months of waiting. Maybe more than that


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## PropGunOne (May 27, 2018)

*Off the Jig*


And glassed internally!

Two very part-time days of work and I had the outside cleaned up and glassed a third time. Some of it even looked good. That’s three layers of 10-oz glass cloth.












Some not so much. Things were hiding in the shadows.












Popped her off the jig by myself. Got the sponsons lifted up with the help of some composite shims-turned-wedges, worked my way under them and when she came loose, slid the hull forward. Out it came. Maybe sixty very awkward pounds, probably slightly less. 3.5 sheets of foam, 3.001 gallons of epoxy and about 20-25 yards of glass, much of it in the trash can as scrap.






































Those lines tho.














And light.



For the inside I swapped over to polyester-based resin. Partly for cost, partly for construction ease and partly because I’ve never really used it and want the experience. The first and last part of that are pretty straightforward. The middle part not so much.

Here’s why I liked the idea of poly. First, I can tab in everything with chopped strand mat, or CSM. CSM is just randomly arranged glass fibers all stuck together with some type of binder, usually styrene-based. Unlike cloth, where it’s woven nice and pretty, CSM is a mess of fibers pointing every direction. When wet out with polyester resin and rolled flat, however, they break apart from their bonds and lay nice and flat and conform to weird shapes much better than cloth does. Additionally, CSM isn’t cut, you tear it like paper, so the edge you are left with isn’t a clean line you have to fair out later, it’s a gradually thinning strand that just sort of disappears into the rest of the surface if you use it right.

But it’s also a resin hog, and that resin likes to kick off fast when it’s above about 80-degrees. Two things happened to me: first I ran out of resin. Two gallons to putty and get CSM into the interior, and that was only making it to the transom. Finishing the sponsons required a third gallon. That’s for one layer of fabric after making it through three cloth layers and putty on the outside with almost the same amount of resin. The second thing that happened it I tried to do it all at once, slightly overlapping my “joints.” Where I screwed up was that some joints were on top, but because of how I staggered pieces when I laid them out, some were underneath other layers that were already wetted out. Basically the cloth had nowhere to roll flat to because earlier portions had already kicked, even at 1% MEKP, and I ended up with what you would call a Soup Sandwich. Total mess. I quit, let the stuff I already laid down fully cure (about two hours, thank you polyester) and ground out the folds I’d created. Once I learned from my mistakes I had no further issues going forward.

A wet-out layer of CSM is heavy, and I had a few spots pull away from the most vertical sections, again requiring grinding. This to me was the greatest benefit of poly – no overnight cure times like epoxy. You can screw up, work on something else, go back and grind and fix your errors, and re-do it in an afternoon. CSM is also VERY easy to patch, as was the cloth, disappearing to the point where I couldn’t find my repairs once they’d cured. A downside is that the vigorous rolling required during wet-out slings the ultra-thin resin everywhere and I ended up with droplets all over me, the hull and the garage floor. Oh well. When the CSM cured I added a layer of 6-oz cloth on top. Wetting that stuff out bordered on orgasmic after fighting with CSM for two days.








































Started working on the layout. Confirmed that I probably didn’t have enough foam to build a self-bailing floor. Instead what I’ll do is have an open, “wet” rear bulkhead for gas tank and anchor storage and a dry, forward bow hatch. The raised sit will now sit on top of the aft deck, sealing it from below and keeping it and the interior will be sized to maximize size 3700 tackle boxes. Great, got it figured out. Maybe I’ll try to create some kind of sump in there. Onto gunnel supports.

In the molded design, the cockpit lacked an under-gunnel space. For ease of construction off a mold, the cockpit was a giant tub, molded onto the gunnels. The whole assembly would drop into the hull and rest atop a large central stringer. Where the stringer terminated there would have been a sump with a standard 1” plug in it. Drawing less than 4” you could leave the plug out and the boat would be self-bailing. More than that and you plug your hole and carry a Clorox bottle for bailing should you need it.

But because there’s no floor, and because this isn’t a molded boat, I got gunnel space back. Patterned the inside hull with cardboard and a holt-melt glue gun and went to work. Transferred my pattern onto doubled-up pieces of 1/2” foam and created gunnel supports/rod holders. Above you can see one finished and rounded off, ready for glass, and the other in it’s rough, one-hole-only form. Because of the curve of the bow, I will likely only run fly rods with the tips facing aft. That allows me to use an unbent tube to insert the tips into. Going forward I would have to bend the tubes significantly. This would not be the case with the plans as drawn as the rods would be another 4” or more away from the hull’s sides. Hard to explain, it’s all just angles


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## Pro wader (Mar 26, 2018)

AWESOME!!


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## DuckNut (Apr 3, 2009)

I am glad you came back to your project and plowed forward.

You did come up with a great little design and it looks really cool. Looking forward to seeing the completed project.

Way to go PropGun.


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## PropGunOne (May 27, 2018)

Gunnel supports/rod holders all glassed. Doing the inside edges of the guides wasn’t fun. Ended up laying a whole piece of glass along either side, cutting off the excess from around the rod guides and then running a second layer of glass in about 1” wide strips through the openings. Tried to do it in one long strip along the edge and failed miserably. There will be some sanding involved but nothing too drastic. 

As the rear deck area will be wet storage I didn’t want water to be able to get all the way to the back of the sponsons. Patterned a couple bulkheads to seal them off and will glass them up tomorrow. Most likely will fill the cavity with flotation foam, though in order to get a level float if swamped I’ll also have to foam an area in the nose. Patterned supports for the bow area as well.

Transom built up to an 18.5” height and 1.5” thickness and be glassed in 10oz with epoxy resin. Deck will slide flush underneath the little forward piece and everything will be tabbed together.

For the conchfish guys... how are you doing flotation foam, if you are? I don’t have a final weight on the boat yet so calculating my requirements is only a guess at this point.


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## PropGunOne (May 27, 2018)

Rod holders/gunnel supports glassed in place. Patterning the deck. Remaining bulkheads filleted and everything tabbed in with 1.5oz CSM. Going to handle the deck the way some others have by pre-building hatch channels and install them into the deck rather than build a mold. Should only be once hatch, have a different idea for the elevated seat. 




































































Undecided on buoyancy foam. As of right now it’s light enough for me to easily get it on and off the saw horses by picking up one end at a time. Make a drain tube from a 3/4” PVC mandrel, rolling 10oz glass onto it until it looked thick enough. Super scientific engineering. Inside diameter was close enough that I could crank a t-post plug into it snug, but it required a lot of cranking. Didn’t like it so I dipped the tip in a straight resin mix to build it up. Good and snug now.


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## PropGunOne (May 27, 2018)

Hung the motor today and confirmed a fear I’ve had since I foamed it... the notch is a bit too narrow. More specifically, it flares upward too much, so that the plastic shaft housing contacts the sponsons before reaching full turn. Also getting some minor contact with the cav plate, which I’d sort of anticipated. Have the motor set pretty high up, about 1.5”. Leveling with the keel would eliminate this, as would taking a grinder to the edge of the plate. Surgery time.

























Had three options with how to fix it. I only needed a couple inches, so I went to the rear bulkheads, which were originally only there to keep water out of the sponsons and provide a mounting location for any future electrical goodies. Took a grinder to my freshly installed tabs and fillets. Then a took a fine-toothed saw and, using the back of the bulkhead as a guide cut all the way down the sponson to where the hull started curving. Left enough kerf to get a good bead of epoxy in there. Mixed up some thickened epoxy and, after squeezing the inside walls vertical, ran some pretty heavy fillets into it. I’ll glass the crap out of this after rounding and cleaning up the edges, using overlapping sheets of 10oz. Hopefully it holds. I gained 2.5” of width.

The other two options were to grind the interior of the sponson back to bare glass, lay a couple sheets of foam in there and reshape with a grinder from the outside in. It would work, but it’d be a lot of work and not real easy to keep everything identical. Another in-depth option would be to push the entire transom aft, adding about a foot of interior space, but that doesn’t sound fun either. 

This was probably a combination of switching to a foam sandwich build, losing 1” of clearance plus glass thickness, and the draft angle we built into it.


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## K3anderson (Jan 23, 2013)

[QUOTE="This was probably a combination of switching to a foam sandwich build, losing 1” of clearance plus glass thickness, and the draft angle we built into it.[/QUOTE]

Can you go even narrower than this so you can lift the motor even higher? The problem is that you will need 14' of water to run like this or tip of skeg to bottom of hull + draft. That is the same problem the solo has. It needs way to much water to run in, but, float ridiculous shallow. If you can narrow the sponsons more, you would be able to make full turns on the motor without hitting. You also don't want the prop blades to hit the sponsons if the motor is tilted (When going over a bar etc.) \. I don't know what that would do to your flotation though. Now is the time to do all that though.


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## Moonpie (May 12, 2020)

Thank you for taking the time and effort to document and post your build.


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## Sublime (Oct 9, 2015)

What did you decide to do about the hook in the bottom at the stern?


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## PropGunOne (May 27, 2018)

Sublime said:


> What did you decide to do about the hook in the bottom at the stern?


Nothing yet. We were going to test it without the deck in place, but a big part of the transom strength comes from tying in to the deck. Decided instead to go ahead and bond the deck to the hull. After staring at it for an hour over a few beers, we cant decide whether it will be detrimental or the best part of the boat. The hook is more towards the outside/chine edge, almost like a blended version of the chine on some of the conchfish builds. Worst case I can flip the hull after testing, get a layer level on it and grind it down. The rear sponsons are foam filled now, so it’ll give me something to work in to.



K3anderson said:


> Can you go even narrower than this so you can lift the motor even higher?  The problem is that you will need 14' of water to run like this or tip of skeg to bottom of hull + draft. That is the same problem the solo has. It needs way to much water to run in, but, float ridiculous shallow. If you can narrow the sponsons more, you would be able to make full turns on the motor without hitting. You also don't want the prop blades to hit the sponsons if the motor is tilted (When going over a bar etc.) \. I don't know what that would do to your flotation though. Now is the time to do all that though.


Do you mean wider? We made some... interesting modifications yesterday. We get full turn on the motor now. The motor sits relatively high now, about 1” above the keel. I think it may float shallow enough that running at tilt wont provide much water over the prop, but I’m not sure yet. With the sponsons I’m hoping to get a bit of a tunnel effect. Think it would be a neat boat with a tunnel and a jack plate. Were drawing up ideas for a manual plate... based more or less on the same principle a car jack uses. In theory it would just be two machined aluminum plates and a re-geared hydraulic pump. Thats for the next iteration though. The idea with this in really shallow water was to paddle it like a SUP.


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## PropGunOne (May 27, 2018)

With only one hatch to mold out, it didn’t seem worth the effort to build an entire deck mold. Instead I cut all the deck pieces to a roughly 1” over hang, except for the area from the cockpit forward. The bow section was sanded to an exact fit the the pieces gorilla glued together. I marked the location of the forward hatch and then took the whole assembly and moved it to the garage floor, cutting out the hatch opening and glassing the topside with two layers of 10oz in epoxy. Flipped and hit the bottom side with 1.5oz of CSM. Plenty stiff. I inserted 1x3s along the outer perimeter and hit them with the nail gun. Cedar 1x2s went in to form the hatch lips, also nailed. I was then able to remove the whole assembly, clay and wax it and set it up on a sheet of melamine with wax paper under it. It got three layers of 1.5oz CSM, which means about 5 layers in the corners with the overlap and the fact that I’m still not great with CSM. The stuff really becomes invisible as you lay it.

I’d sanded a very small draft angle into the 1x3s and used a 3M marine high performance wax I found at Academy. Worked great, mold didn’t even put up a fight. Almost disappointingly easy.

With the deck fully cured, I placed it back on the hull, ground the overhang to within 1/4” and started marking hardware locations. While I was at it I trimmed the flange on the hatch gutter and marked its outline on the deck. Set a straight bit to the gutter thickness and ground out the glass, working the hatch hole open until it accepted the gutter.

Deck came back off and all hardware had backing plates built up from layers of cloth and CSM. Foamed the back sponsons after installing the transom tie-down eyes. Waxed a small grout bucket I had and hung that into the sponsons between to melamine boards with weight on top. As the foam expanded it worked around the bucket, leaving a decent in the foam. If I ever feel the need I can go back and put some inspection plates in the sponson deck and I have another two gallons of dry storage. This also means that without grinding out flotation foam those transom eyes are there until the end of time. They received a healthy dose of thread locker and their holes were over-drilled, epoxy filled and 3M gooped during install. Gotta paint around them though. Probably not ideal, but I wanted foam in the sponsons. Took about 1 gallon of foam to filled both sponsons. Didn’t get pictures unfortunately. 

Before all this we hung the motor and started trying to figure out what we needed for clearance. Moving the sponsons apart wasn’t enough. Maybe a 20” shaft and elevated transom would’ve done it, but with a 15” the shaft shroud wasn’t close to clearing. With the motor at full (blocked) turn, we took a measurement about 2.5” behind the point of contact and made a mark. Then we put the straight edge on the motors pivot point, measuring the distance from the pivot to the mark we made, and drew an arc. This was to be the cutout. Eyeballing the motor gave us a rough depth of 5”. The arc wouldn’t be easy to form with foam, so it was translated to a straight line. In went the jigsaw and out came a strange looking notch. Used the cutouts to pattern the foam, built the inserts on the bench and glassed the inaccessible bottom side. Installed the inserts using screws and thickened epoxy. When it hardened we pulled the screws and glassed. Done. Little oversized... a near-zero clearance version would’ve needed a v-shaped vertical notch, but this was easy.

With everything done, and confident the inside could still be faired with the deck bonded, we glued the deck down. Chase tubes make it nearly impossible to get good fillets and glass on the inside after it cured. I kind of regret this now as my original plan was to use sections of tube and couplings for the chase tubes, which would’ve opened up access to the inside edge. Glue joint looked good though, so I used a harbor freight trim router with a roundover bit to curve the deck edges and put tied any remaining gaps closed. This will get a couple layers of glass. I suspect it wont be going anywhere.


Still to do: glass deck into place, install bilge pump and through-hull fitting, figure out how and where to get a fuel hose through the deck, secure all deck hardware, make clamping plates for motor and get it wet. Oh, and a tone of fairing and forming of poling/spray strokes. Long week.


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## trekker (Sep 19, 2015)

Have you noticed any discrepancy in your Carbon Core thickness, sheet to sheet?

I'm about halfway done stripping a build I'm doing and started noticing some differences. Ive used 3 sheets out of the box (full case) and one of them is a full eighth thinner than the rest. So, now I've got several areas that are gonna require fixing before I can glass. Super pissed.

Hull looks good, btw. Super slick design.


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## PropGunOne (May 27, 2018)

trekker said:


> Have you noticed any discrepancy in your Carbon Core thickness, sheet to sheet?
> 
> I'm about halfway done stripping a build I'm doing and started noticing some differences. Ive used 3 sheets out of the box (full case) and one of them is a full eighth thinner than the rest. So, now I've got several areas that are gonna require fixing before I can glass. Super pissed.



Funny you should ask. 










One was definitely 3/8”. Was a little irritated but I used it strategically. One small strip made its way into the deck though. Couldn’t figure out why it wouldn’t sit flat.


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## makin moves (Mar 20, 2010)

With the motor sitting higher when turning are you worried about the thrust coming off the prop going right into the side of the sponsons? Would it making turning more difficult? Will the angle of motor allow the water to be pushed down instead of straight?


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## Sublime (Oct 9, 2015)

All my carbon core sheets were uniform. Thank goodness.


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## K3anderson (Jan 23, 2013)

Sublime said:


> All my carbon core sheets were uniform. Thank goodness.


Same here, I would lose my mind. Too expensive for that BS>


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## K3anderson (Jan 23, 2013)

PropGunOne said:


> Do you mean wider? We made some... interesting modifications yesterday. We get full turn on the motor now. The motor sits relatively high now, about 1” above the keel. I think it may float shallow enough that running at tilt wont provide much water over the prop, but I’m not sure yet. With the sponsons I’m hoping to get a bit of a tunnel effect. Think it would be a neat boat with a tunnel and a jack plate. Were drawing up ideas for a manual plate... based more or less on the same principle a car jack uses. In theory it would just be two machined aluminum plates and a re-geared hydraulic pump. Thats for the next iteration though. The idea with this in really shallow water was to paddle it like a SUP.


Meaning more space between them so the engine can come up vertically and not have the cav plate hit the sponsons on a full turn. I think it's too late now. You can now clear the sponsons when the cav plate is below the hull, but if you raise the engine (jack plate), will they hit again? That's what I was saying. 

You might also check out that on the fly jackplate that has the handcrank if it won't hit on the sides of the sponsons. That seems like it would be a perfect option for this skiff.


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## StAugStumpy (May 11, 2020)

Really enjoying watching this build. I am a beginner and learning a lot of these techniques from you all. The deck and gunnels are just glassed in? Thats all the securing needed? I want to add a raised deck to my stumpknocker and am trying to figure out how to go about it.


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## texasag07 (Nov 11, 2014)

So what is the main reason for the transom inset to be so far forward?

Low HP planing and trim by having the weight further forward?

Nice work btw!


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## PropGunOne (May 27, 2018)

makin moves said:


> With the motor sitting higher when turning are you worried about the thrust coming off the prop going right into the side of the sponsons? Would it making turning more difficult? Will the angle of motor allow the water to be pushed down instead of straight?


With the curve of the sponsons all the prop thrust should be below them. I could angle the motor closer to the angle of the transom (12 degrees) but as it sits now its positioned vertically. I could go up a trim pin spot and angle it upwards more, but I suspect water rising from the keel into the void between the sponsons will have a bit of a tunnel effect, so for now I’m leaving the cav plate level with the keel. It could angle up a couple trim pin spots and still clear for rougher conditions... at two spots the plate might hit but the prop should still be clear.



StAugStumpy said:


> The deck and gunnels are just glassed in? Thats all the securing needed? I want to add a raised deck to my stumpknocker and am trying to figure out how to go about it.


There’s a 2” flange at the top of the hull, basically a seat for the deck to rest atop. That entire flange is coated with a glass bubble and cabosil thickened epoxy. There’s about 1000 ways to glue this joint. There are specialized bonding putties that cost a fortune but for the loads involved here probably just aren’t necessary. Ive heard of many people just using 3Ms 5200 product as well. Ive only ever used it for through-hull and deck fittings, but my understanding is that it remains slightly flexible, so I didn’t use it. Probably nothing wrong with it though.

After laying down a ton of the thickened epoxy glue (think tiling a floor, but about double) I let it cure. Flipped it the next day to try and lay fillets on all the reachable inner joints. Because of my chase tube placement this was just about impossible. Not enough room to maneuver. All the joints I could see had good overflow though, so I feel okay about it. Yesterday I took a trim router with a 1/4” roundover bit, rounded the edges of the deck and flange into a soft curve, and glassed it today. Ran out of 10oz (have some left but saving it) so I glassed the joint with 2 layers of 6ox glass in epoxy. Not going anywhere.



texasag07 said:


> So what is the main reason for the transom inset to be so far forward?
> 
> Low HP planing and trim by having the weight further forward?
> 
> Nice work btw!


Biggest reason is modern engine weight on a small boat. My SK14 claims 3”, but its scupper hole is at 5.5” above the keel and still takes water in with me in the back. Four strokes are heavy, and people don’t like them for that, but I like the clean burning, quiet, oil-free nature of four strokes. To offset both the engine weight and the lack of buoyancy in a small skiff Chris came up with the notch. It may be a little huge... could probably lose a foot of it and be fine, but it’ll definitely get the job done. The reasons you listed are all benefits.


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## PropGunOne (May 27, 2018)

Boats done... kinda.
































Ran her for about 20 minutes yesterday morning. First laid foam on 4/15. Hull, minus finishing and full rigging, was complete on 5/26. About 23 days of full work and the remainder as half/quarter days. Lots of time in there standing around and staring at it trying to figure things out. 

Can’t figure out how to put video up on here yet (haven’t tried that hard to be honest), but here are the initial impressions:

- 18.4mph with a 8HP, 87lb Tohatsu.
- Quiet
- Excellent turning at speed. Video up on IG, but half-throttle with a phone in my hand it was making me dizzy without turning the motor all the way to the stops
- Little slippery as it first gets onto plane, which happens in about 3 seconds. To be expected with soft chines and no strakes yet
- Low speed maneuverability SUCKS at the moment. Took two shots to get on the trailer with a moderate crosswind/current. Think the biggest reason for this is the weight distribution. Too light in the front. I had a battery and 3gal tank under the rear deck. Might be a good candidate for a trolling motor up front. With some added weight up there it should balance out and pivot on its axis a little better.
- Definitely no tiller extension here. Rear deck could actually be longer but I wouldn’t do this unless I had access from above. Elevated seat not yet built and I kind of like the wet storage option.
- My bilge pump setup sucks and needs work. As I originally thought I would have a floor in here, I didn’t bother forming a sump. The auto pump doesn’t kick on until water fills the bilge almost to the rear bulkhead. It works for how it needs to, but it isnt optimal. Going to have to get creative... or build a floor. 
- No official weight, but I’d guess everything minus the engine is about 180lbs. Would’ve been way less with epoxy. Can’t even feel it on the trailer.
- Stable through the middle 2-3 feet, tips beyond that. Gunnels are walkable but better suited for sitting. No issue standing on the nose, very flat with the plumb bow and no slapping inside the sponsons. Sponson draft was about 4.5”, but again, due largely to weight distribution and that hook I managed to build into it. No ill effects from the hook that I can tell, though it probably doesn’t help the low-speed handling. 

Skiff is in Daytona now and will be on Captiva sometime tomorrow. Going to beat the hell out of it for 8 days, figure out her quirks and proceed from there with tweaking and finishing. Overall very happy. Faster than my SK14, though not significantly so, but with about 800x the storage, no hull noise and lighter weight. Prop job may help with the speed.


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## K3anderson (Jan 23, 2013)

Did you add the strakes on the bottom? Would this help at all? What do you think the optimal motor is on this?


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## PropGunOne (May 27, 2018)

No strakes yet. I don’t know that they’d help with being able to spin it around it’s axis, that’s more a matter of getting weight forward to lift the back. It’ll get those prior to finishing. I think a 9.9 might be about perfect, 15 would be fun. Long shaft might help some of the sponson clearance issues by getting the bell housing portion above the notch. To be honest though it feels fast enough with an 8.


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## K3anderson (Jan 23, 2013)

PropGunOne said:


> No strakes yet. I don’t know that they’d help with being able to spin it around it’s axis, that’s more a matter of getting weight forward to lift the back. It’ll get those prior to finishing. I think a 9.9 might be about perfect, 15 would be fun. Long shaft might help some of the sponson clearance issues by getting the bell housing portion above the notch. To be honest though it feels fast enough with an 8.



The 15 and 20 both weigh the same. All things being equal (cost) seems like the 20 would also be fun w/o adding any weight.


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## Randy Kaneer (Jun 5, 2020)

After the test run are you satisfied with the length? Is there a 16 foot option?
Randy Kaneer


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## PropGunOne (May 27, 2018)

Sorry, been busy.

No 16’ option per say, but I think you could reasonably stretch dimensions by 10% and be fine. At that length such a significant notch is probably not needed. A big reason we did that was (1) eliminate a tiller extension, and (2) balance the weight distribution of what is a pretty tiny boat. More length and more beam means more buoyancy, so my 175lbs is a less significant moment in a 16’ boat than it is on a 14. I might still notch it some, but it would be more “traditional” in shape and scope.


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## PropGunOne (May 27, 2018)

Out of paint. Chines sharpened, EZPoxy topsides in semi-gloss white and ice blue. Tinted EZDeck paint with a 6:1 ratio of ice blue for some contrast. Currently rigging, which for now is line spikes, deck hardware, a battery, bilge pump and probably gps/fishfinder. Lights will come later. Boat should be “done” in a day or two. Videos to follow.

I was very pleased with the on-water performance, though it had a habit of ventilating when running fast over shallow water. Couple possible reasons why. Going to see what she does with a cleaned-up bottom and go from there.


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## PropGunOne (May 27, 2018)

And done. Just gotta throw in the battery and gas tank.


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## bryson (Jun 22, 2015)

Looks good! I'd throw a step in the round transom corners if it's not too late, just something to help the flow separate cleanly at speed instead of trying to peel around the transom.


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## PropGunOne (May 27, 2018)

bryson said:


> Looks good! I'd throw a step in the round transom corners if it's not too late, just something to help the flow separate cleanly at speed instead of trying to peel around the transom.


I considered that, but the inside sponson curve begins about 4” from the outside of the chine. Hard to see in the picture, but there really isn’t much to work with for shaping that edge.

Took it out today for its first finished run. Expected a little more than the 18mph I was originally getting, but instead am only getting 15 now. I think what’s happened is that my spray/poling strakes have also become lifting strakes... excessively. Boat is super-dry now but the bow rides high. Won’t quite settle into plane. I’ve got one notch left for down-trim on the pin. Going to angle it down and see what she does. Short of that the strakes are getting trimmed.


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## Pole Position (Apr 3, 2016)

Did the "dirty water" @ the prop clean up w/ the finished bottom?


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## PropGunOne (May 27, 2018)

Pole Position said:


> Did the "dirty water" @ the prop clean up w/ the finished bottom?


No longer seems to be an issue. Been in FL for four days so haven’t had a chance to play with trim settings yet.


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## Open Fly -The Later Years (Feb 1, 2020)

Jon,
Have to tried to find video on instagram, unable to find your instagram site
Please give me the address. I am much heavier than you ,250, interested in stability 
on the side decks and bow and stern decks. Good looking build ! I am interested.
Please let me know


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## Pole Position (Apr 3, 2016)

Open Fly -The Later Years said:


> Jon,
> Have to tried to find video on instagram, unable to find your instagram site
> Please give me the address. I am much heavier than you ,250, interested in stability
> on the side decks and bow and stern decks. Good looking build ! I am interested.
> Please let me know


Try .... propgun_studios,,,for IG

His website, www.captive-skiffs is no longer active


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## Open Fly -The Later Years (Feb 1, 2020)

Pole Position said:


> Try .... propgun_studios,,,for IG
> 
> His website, www.captive-skiffs is no longer active
> 
> Still not able to find on Instagram propgun_studios


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