Building a ply dinghy.
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Category: General Forums
Forum Name: The Boat Shed
Forum Description: Discuss all things boating.
URL: https://www.fishing.net.nz/forum/forum_posts.asp?TID=124791
Printed Date: 18 Apr 2024 at 12:15pm
Topic: Building a ply dinghy.
Posted By: OneWayTraffic
Subject: Building a ply dinghy.
Date Posted: 12 Jul 2017 at 10:41pm
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Currently being without a boat I am building a little dinghy. The build thread will be on Bateau.com. If I enjoy the whole process and at the end of it I get something I don't mind to admitting that I built I may try something bigger... Use will be for trout fishing canterbury lakes, crossing the Hurunui river lagoon going after salmon, and mucking around Nelson. https://forums.bateau2.com/viewtopic.php?f=14&t=62403" rel="nofollow - https://forums.bateau2.com/viewtopic.php?f=14&t=62403 |
Replies:
Posted By: smudge
Date Posted: 12 Jul 2017 at 10:58pm
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I hope the build goes well, will be watching it develop ------------- Best gurnard fisherman in my street |
Posted By: yknot
Date Posted: 13 Jul 2017 at 5:51am
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Great project, please post updates on your progress. ------------- Those that say it can't be done are being overtaken by those doing it. |
Posted By: Don18025
Date Posted: 13 Jul 2017 at 9:06am
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Good on you. Used to be common here in NZ to build your own dinghy. We had some great designers supporting home builders plus many keen builders designed their own. In this weather building in shed is better than being on the water. Look forward to your project. I have another in the planning stage - an old style clinker built in glued lapstrake. |
Posted By: MarkE
Date Posted: 13 Jul 2017 at 9:57am
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Good on you mate, Ive been thinking along the same lines for a similar project now that im landlocked :P ------------- Sea Strike 18' Centre Console - Under Construction.... http://www.fishing.net.nz/asp_forums/sea-strike-18-build-thread_topic87723_page1.html" rel="nofollow - Build Thread here |
Posted By: MikeAqua
Date Posted: 13 Jul 2017 at 11:30am
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Nice one. How does the saw-max tool go on curved cuts? |
Posted By: OneWayTraffic
Date Posted: 13 Jul 2017 at 1:20pm
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The saw-max cuts about 2mm wide. Curves are no problem as long as they are smooth fair curves. No problem with the curves for those panels. Router or jigsaw for finer work. One thing though. I was cutting flat on the floor with cardboard under to keep the concrete from the blade. I did get build up of dust in the cut every meter or so. Easy to clear once I figured it out. |
Posted By: Steps
Date Posted: 13 Jul 2017 at 3:13pm
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In the 50s and 60s damn near ever garage had a dinghy built in them.. Think it was the old hartley design or out of Popular Mechanics mags These days things like fixtures/ glues are far superior. We made kayak cannoes.. ply off cuts, ripped a few stringers, brass scews canvas and old house paint...Did from Amuri damn to port waikato, Clevedon to Waiheke and back and a few other trips Those plans where out of a popular mechanic mag... we where about 14/ 15yrs at the time. |
Posted By: OneWayTraffic
Date Posted: 13 Jul 2017 at 4:03pm
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This boat is stitch and glue. Supposed to be fast and easy construction. I'm drawing and cutting the rest of the panels at the moment. Gluing will have to wait until the weather warms up a bit. Too cold for even fast hardener. Most photos and info will be on the linked bateau thread though I'll keep this updated from time to time. I can understand why building is going out of fashion. I will have a bit over $1000 in materials in this by the time I'm done. |
Posted By: MikeAqua
Date Posted: 13 Jul 2017 at 4:43pm
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I've been looking into stitch and glue. Planning a kayak build later this year. With the S&G build system specified, the ply ends up completely encapsulated in and joined together by epoxy, so its more or less functioning as a very strong core material. A bit different to the old glass over ply with metal fastenings. |
Posted By: OneWayTraffic
Date Posted: 13 Jul 2017 at 5:05pm
| I had a bit of a play with the epoxy before buying Ply. Incredible stuff. Unlike polyester it is tenacious at gripping to the wood. This will have 400g biaxial on seams inside and out. Paint everything except the bottom which will have an aluminum powder coating. |
Posted By: OneWayTraffic
Date Posted: 13 Jul 2017 at 7:08pm
I was impressed by the look of your SS18 when I saw it. Always thought that that would be too much project for me. If this goes well I'll probably either go for a FS17 with high sides, or decide that one will do me and buy a 5m frewza, Smartwave or something.
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MarkE wrote:Posted By: filthyoar
Date Posted: 13 Jul 2017 at 7:12pm
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Mate I've not long finished a 12ft tango skiff best fun ever looking forward to your build |
Posted By: OneWayTraffic
Date Posted: 13 Jul 2017 at 11:34pm
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I was wondering if it was possible to see the pictures on the bateau thread without a login? I can post some here as well. |
Posted By: JustAnotherSpearo
Date Posted: 14 Jul 2017 at 7:24am
Would love to see the photos here as well if you don't mind. Interesting to keep tabs on this and see how you go 
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Posted By: Don18025
Date Posted: 14 Jul 2017 at 9:23am
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Here is a couple of Kiwi stories well worth following. Both building one of the best 12 footers ever designed.....put 20 hp on it and you have a great fishing and dive boat. http://forum.woodenboat.com/showthread.php?171585-Frank-Pelin-12-quot-Nomad-build http://scottjcarpenter.blogspot.co.nz/ Enjoy and may it encourage your work.
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Posted By: OneWayTraffic
Date Posted: 14 Jul 2017 at 10:28am
   Photos of marking and cutting hull panels.  Excerpts from plans. I paid about $50 for the plans. High school maths and knowledge of coordinates is useful. It would be easier if I had a bigger set square but I am managing with multiple measurements and double checks. Accuracy within 5mm is accepted as gaps can be filled with epoxy putty. Gaps make a stronger final product. |
Posted By: OneWayTraffic
Date Posted: 14 Jul 2017 at 12:31pm
| That's a nice 12 footer. I considered building a stitch and glue 12 foot but wanted to keep the size to where it would fit on a garden trailer. With the method I'm using a 14 foot can be made for almost the same cost anyway. |
Posted By: makka
Date Posted: 14 Jul 2017 at 12:40pm
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Looking good mate, I'm still toying with building a bateau FS14-LS or FS14. Where did you source the ply from? |
Posted By: OneWayTraffic
Date Posted: 14 Jul 2017 at 7:12pm
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BBS timbers. Roughly $75-$100 a sheet. Seems to be decent stuff. No voids or defects noticed yet. There were a couple of fs14s on trade me a while back. Make sure that you build the boat you want as homebuilt boats don't sell well. Personally the fs17 seems like much more boat. |
Posted By: smudge
Date Posted: 14 Jul 2017 at 8:30pm
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Talk about getting stuck in One Way! Good work. Second that on home made boats not selling well. When I bought my current boat there was a stunning looking CC for sale. It didn't suit what I wanted but it was so tempting. It just didn't look right for bar crossings but was a beautifully crafted 6m with a Yamaha 150 on the back all only a couple of years old. It sold for 18k. ------------- Best gurnard fisherman in my street |
Posted By: Schampy
Date Posted: 14 Jul 2017 at 9:12pm
| Yep agreed. You build home builds for the love of doing it yourself. At best you get back the cost of your materials. There is a tremendous amount of satisfaction crafting a boat in your back yard/garage...And is also very addictive . Funnily enough when it comes to building a mid sized boat the cheapest part of the entire build is the hull itself. Still though, its a great kiwi tradition to have a go yourself. Its never failed to amaze me at what ordinary people with little or no wood working experience can knock up in there sheds! |
Posted By: OneWayTraffic
Date Posted: 14 Jul 2017 at 10:26pm
| Count me as a one of those woodworking novices. I can read and follow instructions though. Ironically once I started reading about building I became aware of all sorts of cost cutting measures used by the pros where an amateur would do a better job. Take the sea nymph rebuild thread. Those stringers should have been epoxy encapsulated. Most fiberglass boat makers drill holes in their transom and use sealant. I'd drill over diameter, fill with thickened epoxy and then drill the bolts. No possibility of water getting to the wood. I would pay a fair price for a homebuild but I would need to know it was built right. |
Posted By: OneWayTraffic
Date Posted: 15 Jul 2017 at 10:36pm
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http://www.bateau2.com/free/D5_free_m.PDF Found a link to free plans here. I paid for more detail but the basic boat is the same. |
Posted By: Don18025
Date Posted: 16 Jul 2017 at 5:18pm
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That is a great start One Way. You are learning from small beginnings. But be careful it is life consuming - creating boats out of wood (a marvellous material). I started with an 8 foot Plylite pram dinghy kitset.....caught more trout in that boat than any since. It was painted green for duck shooting season. And my largest creation - to build this;  Yes they just get bigger.....do not tell the wife. But everyday I worked on it I enjoyed. 3.5years from plans being drawn until launching. I did have a professional boatbuilder help me with the challenging parts and he taught me lots about dealing with wood.  |
Posted By: MikeAqua
Date Posted: 17 Jul 2017 at 1:26pm
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As the plans have loftings I'd be tempted to digitise them and have it CNC cut ... |
Posted By: OneWayTraffic
Date Posted: 17 Jul 2017 at 8:39pm
| If I had my own CNC router I would be tempted as well. As it is drawing and cutting isn't a major hassle, just part of the project. I am part way through cutting out the frames. My dremel blade is getting old and starting to burn the wood. Hopefully it will last long enough. |
Posted By: OneWayTraffic
Date Posted: 19 Jul 2017 at 7:50pm
Frames and 2 out of three seat tops cut. The last seat top will have a big hole in it for the anchor etc. slight cutting mistake in a couple of frames but hopefully that will disappear once it's covered in epoxy fillets.   That's a 600mm ruler for scale. It would have helped to buy a large set square. |
Posted By: OneWayTraffic
Date Posted: 19 Jul 2017 at 11:57pm
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I spent about three hours stitching and wrestling with hull panels. Bigger boats are built on a jig and now I can see why. Most of the panels seem to be falling into place though it took a while to get everything lined up. I bought a packet of 300 cable ties and a good thing too! I am trying to have everything less than 1cm from where it should be. It takes a lot of tying, cutting and retying. I will probably need to screw a corner down. If I can get it mostly symmetrical then that will do. |
Posted By: OneWayTraffic
Date Posted: 20 Jul 2017 at 12:00am
      
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Posted By: MikeAqua
Date Posted: 20 Jul 2017 at 8:16am
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Wow. I'm impressed you can build that without a jig. Can you tell us a bit more about the aluminium powder coating that will go on the hull. |
Posted By: OneWayTraffic
Date Posted: 20 Jul 2017 at 9:51am
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I was impressed too. Because it's not a planing hull it won't matter much if it's not completely symmetrical. I am not done with the stitching yet as I want to get it as close as I can. I figure that will mean less grinding and fairing later. The aluminum powder is a west system additive. Apparently it adds UV resistance and makes the surface harder. You can add as much as you want as long as you can spread it. I've never used it; this is my first build and first time using epoxy or fiberglass. When I get to it I'll try on a scrap and try scratching it with a rock or knife. |
Posted By: OneWayTraffic
Date Posted: 20 Jul 2017 at 4:23pm
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Today I finished stitching. Used a carbide head on a multi tool to sand down one of the assymetrical frames as it was applying uneven pressure to the bottom. Frames held in place with cable ties and the odd temporary nail. No metal fasteners remain in the boat. All holes will be drilled to 4mm and filled with epoxy. Duck tape arround all external seams to help hold but mainly to stop epoxy leaking through when I glue and fillet the inside.   I'm done with assembly. Diagonal measurements are 2420mm and 2440mm. A difference of 0.8%. I can get them identical by applying a bit of pressure and may do that when I glue if I can figure out an easy way. Need to wait for a 24hr period with temperatures above 5 degrees to build the inside seams. |
Posted By: OneWayTraffic
Date Posted: 21 Jul 2017 at 11:56am
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Learned a neat trick too late to use it. When drawing out the panels, I at times struggled with getting perpendicular lines more than a short distance from the edge of the wood. Line up two panels of ply, and slide one across the other so the sides are aligned. Then draw perpendicular lines using the edge of a sheet of ply as a guide. The hull markings on my plans were at a typical distance of 305mm, so that's how far apart the lines should be. Then mark the offsets directly on the typical lines. |
Posted By: CrayZfish
Date Posted: 21 Jul 2017 at 12:26pm
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Looking good. Enjoy the rest of the build. For some motivation I finished this little 2 sheet dinghy recently for my boys initially as a sand pit but I glued and fibre glassed all the joints with the future in mind for them to take on the briny. Not sure exactly how it will go, but as soon as they are over the sand pit it will be getting a new coat of paint and will be tried and tested initially in the pond then hopefully on the harbour afterwards. Great little project that cost about $200.  ------------- Why choose either diving or fishing when you can do both. Besides crayfish tail is very good bait!! |
Posted By: OneWayTraffic
Date Posted: 21 Jul 2017 at 5:43pm
   Glued the inside. Wetted out most seams with epoxy. I then used epoxy thickened with fumed silica (west system filler) and a ziplock bag as a dispenser. Took about 3 hours. I tried to use a mixing stick and the rounded corner of the fiberglass spreader to give a neat finish and a radius but I will probably need to redo them when I glass the seams anyway. Used a heat gun and soaked the epoxy bottles in warm water to try and get things flowing nicely. |
Posted By: OneWayTraffic
Date Posted: 21 Jul 2017 at 6:21pm
| For those wondering. The cable ties will be removed or at least ground flush once the glue cures. Then I will be back to fill the gaps, build correct sized fillets and fiberglass. |
Posted By: kitno
Date Posted: 21 Jul 2017 at 6:45pm
Good thread OneWayTraffic, enjoying your updates  ------------- Top 10 finish 2024 Grunter Hunter. |
Posted By: OneWayTraffic
Date Posted: 21 Jul 2017 at 7:34pm
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It's been a real learning experience. I must admit to thinking about building bigger. I have plans for both the Bateau FS17 and OB17 and have been pondering other, bigger designs. In NZ most trailer boats follow a particular layout, and the bigger the boat the bigger the motor. There's a lovely Mac600 on trademe. I would love to own one, the price is fair, but a 115 Tohatsu twostroke that uses 50l an hour at full throttle, and a 1000kg tow weight puts me off. Building, I have seen semi planing, lower speed hulls that get 40km per hour on 50hp, weighs under 500kg fully rigged out, and is over 6m long! |
Posted By: Schampy
Date Posted: 21 Jul 2017 at 8:19pm
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Looking great one way. Try grinding a nice circular arc on a cheap metal putty knife to help get nice big fillets. Its worth getting all your joint tape ready to go so once all your zip ties are snipped and coving done you can apply your biaxel (?) tape to achieve a nice chemical bond between fillet and fiberglass. Have a look at the Bowdidge website if you want ideas for another project. Mark designs fantastic boats.
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Posted By: otdrmn
Date Posted: 21 Jul 2017 at 9:00pm
I was the first to build the OB17 and got a second set of plans for free as a result of this. Great boat and fun to build. ------------- The 4 R's ~ Rods, Reels, Rifles, Rooting |
Posted By: OneWayTraffic
Date Posted: 21 Jul 2017 at 9:31pm
Will be 400g biaxial. Should be enough to hold together. 400 is overkill, twice what the plans specify, but it was either that or 200g woven. I'd rather overbuild than underbuild. |
Posted By: OneWayTraffic
Date Posted: 22 Jul 2017 at 7:02pm
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There were a few seams that came out perfect, and more than a few that look like the epoxy monster vomited all over them. I have no plans to glass until I can get the inside of the boat sanded and the lumps and bumps knocked down. Then some consistent fillets and glass tape wet on wet.
On the bright side I spent an hour of quality time with my oscillating multi tool and its silicon carbide head... Many more hours to come I am sure. I am aiming for a workboat by use, and somewhat better by appearance. I want the appearance to be good enough so I can practice the skills and not be ashamed to admit that I made it. |
Posted By: OneWayTraffic
Date Posted: 23 Jul 2017 at 12:33am
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Sanding, sanding, sanding. I won't post here again unless there are any questions or until I have actual progress to report. Takeaways: Epoxy holds very strong, don't overdo the tack welding and get a decent fillet tool! I used a lot lot more than I needed. Spending more time stitching evenly pays in spades when it comes time to glue and fair. |
Posted By: MikeAqua
Date Posted: 24 Jul 2017 at 10:22am
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[/QUOTE]
I was the first to build the OB17 and got a second set of plans for free as a result of this. Great boat and fun to build. How does the OB17 handles a short sharp chop? |
Posted By: OneWayTraffic
Date Posted: 24 Jul 2017 at 10:45pm
| There is plenty of info on Bateau about them. The FS17 is the better boat in a chop as it can run at any speed with no planing hump. The ob17 has a bit more deadrise but isn't as smooth in a chop. Higher top speed and takes a load better apparently. |
Posted By: OneWayTraffic
Date Posted: 24 Jul 2017 at 10:46pm
| I have the plans for the ob17 but won't build it. I can sell them for half what I paid. |
Posted By: Govtgirl
Date Posted: 25 Jul 2017 at 3:24am
| Have any of you tried Flexseal on the joints? Advertised heavily in US as monster holding tape even in water, but don't know how it would do over time |
Posted By: MikeAqua
Date Posted: 25 Jul 2017 at 8:14am
I'm surprised to read that, I thought a flat bottomed skiff would be awful in chop? |
Posted By: OneWayTraffic
Date Posted: 25 Jul 2017 at 11:18pm
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The FS17 has a flat deadrise at the transom. At the cutwater where it matters it is 25 degrees. If you slow down in a chop it should give a smooth ride for a boat of its size and type. Since the boat can be driven at any speed it should possible to find a speed that fits the conditions. That information is straight from the designer, looking at the plans and reports of the many people who have built the boat, not from my own experience. Seaworthy is a subjective term. Each boat is seaworthy but they behave in a different way. The FS17 will run smoother in a formed sea but as you guessed, be less stable at rest or slow speed. The C17 will have a more snappy roll. The FS17 will handle semi-planing speeds better than the C17 but the C17 can take more HP and will have a higher top speed. -Jacques Mertens. (comparing to the C17, a much bigger boat.) By the by most NZ boats have a definite transition to plane. The choice is often either planing at 35-40km/h or wallowing at 10km/h. It is not easy to find a boat that will efficiently travel at semidisplacement. Pangas are the only ones I can think of offhand, also flat bottom over the back half of the boat and also known to eat up rough water at appropriate speeds. |
Posted By: OneWayTraffic
Date Posted: 25 Jul 2017 at 11:28pm
If you mean using it to stitch the joints together, then I would try it. I am not aware of anything better than epoxy and fibreglass for a permanent joint. It penetrates the ply, is stronger than the wood as a glue, wets out glass fibres to form a composite, is waterproof, inert when cured, can have fillers added for different applications, acts as a primer for paint, will not rust rot or corrode. Whats not to like? The only thing to watch is UV. Just looked at the ad. I wouldn't use that on the wood. It might interfere with the epoxy. Possibly as an outer spray, but there are many tested paint options. |
Posted By: OneWayTraffic
Date Posted: 25 Jul 2017 at 11:35pm
| Update on the dinghy. Spent an hour tonight sanding, and about 5hours over the weekend. I am almost ready to put glass on, but I really want to do the best work I can, even for a first attempt. |
Posted By: MikeAqua
Date Posted: 26 Jul 2017 at 10:52am
That's one thing I do like about my boat. It will stay on the plane in the chop at 15 knots and in flat water at 13 knots. |
Posted By: OneWayTraffic
Date Posted: 30 Jul 2017 at 4:18pm
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Fibreglassed the back compartment today. As this will be covered, out of sight and filled with polystyrene beads (I will bag them and have a hole for ventilation I think) I did this as my first attempt at glassing. I took the boat outside to warm up in the sun, and put the epoxy in a warm place for a couple of hours. I first went over my sanded, resanded and wetsanded first filleting job with neat resin. I brushed the remainder over where the fibreglass tape will go and over the bottom. Then I went over the fillets with about 125ml of resin thickened with silica (westsystem 406). I used a plastic spoon to make the fillets and found this much better than the last week. I applied the goop with a spoon where needed and used the spoon several times to form the fillet, then the plastic fibreglass spreader to remove excess off the sides and then spoon again. I went over each fillet several times before I was happy. I then painted over the fillet with neat epoxy with a chip brush brushing away from the fillet to smooth things out. Went inside to take a break, have something to eat and let the fillets firm up. I had already cut the tape to size but had not cut slits in the end to help it go around the corners. So I got some epoxy over our good kitchen scissors. (Now cleaned off I hope!) I wet out the fibreglass tape (I didn't count carefully but I think I got about a 40% glass content after using excess resin to wet the wood sides.) I applied one layer of tape, wet it out then applied the second layer on top. I did have issues with the odd bit of stitching getting caught in my brush and getting pulled out and the little bits of glass near the edges of the cut tape pulling out and making all kinds of mess. Photos of the worst spots. After all was done and all the glass was transparent I ran the brush and spreader over the fillets applying a fair bit of pressure to ensure the glass was firmly down, and to try and remove any air bubbles. There were a few places where the tape lifted up here thanks to the friction of the spreader and needed to be pushed back using the brush and my gloved fingers. Later I used a clean brush to go over the whole surface, pushing down errant threads, popping air bubbles, and smoothing over drips and runs. Took about 3 hours start to finish. According to the plans I should have been able to fillet, tape and epoxy coat the entire inside in that time. I can see an expert doing it that fast, but I am happy to keep plodding along. For a first attempt, I am content. 
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Posted By: OneWayTraffic
Date Posted: 30 Jul 2017 at 4:22pm
  
First photo is a close up on the roughest spot. The glass fibres got loose and made a heck of a mess. This will be covered by either the seat top or the outboard clamping pad so no biggy. The next two photos taken by my daughter as I was glassing.
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Posted By: Steps
Date Posted: 31 Jul 2017 at 8:11am
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The glass fibres got loose and made a heck of a mess. Must be knocked back, someone reach upder the seat, they will slice their hand open or snap a dag off in a finger knock them back with some 40 or 80 grit sand paper. inside curves to make lay down better, little more filler in inside joint for bigger radius, and/ or lay some rovings in the cnr, wet out then glass over. For going over outside edges, round them off with a router or disk sander.... Lot of hints on current parallel thread on rebuilding sea nyph |
Posted By: OneWayTraffic
Date Posted: 31 Jul 2017 at 3:59pm
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Yeah I'll go over the whole thing with a sander and put on another coat of epoxy. This whole area will likely be sealed away though and not reachable unless someone cuts into it to put a hatch in. I will still do the neatest work I know how at the time. For the next inside corners I may cut the two horizontal cloths a bit shorter so they don't quite reach each other. Then go over with a third bit of tape. I will also try using a foam roller for wetting out. (Hoping it won't drag the tape around.) I love this project. |
Posted By: MikeAqua
Date Posted: 01 Aug 2017 at 7:25am
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Nice work My first ever attempt at filleting and taping looked a lot worse than that and I wasn't working in tight confines When it's partially cured the little stray fibres can be cut off easily with heavy duty scissors. Needs to be past the sticky stage but not so far gone it's hard to cut. |
Posted By: Steps
Date Posted: 01 Aug 2017 at 11:57am
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I will also try using a foam roller for wetting out. Dont bother get a couple ribbed roller .. they are designed for rolling out.. difference in speed and quality is huge. Couple.. well will lay odds that you will push curing / cleaning down a roller and end up it glued up permanently.. saves having to stop and get another later... For the next inside corners I may cut the two horizontal cloths a bit shorter so they don't quite reach each other. Then go over with a third bit of tape instead of experimenting. messing around.. either pre radius with filler... and if raduis little small, layer wetted out rovings then glass directly over them. |
Posted By: OneWayTraffic
Date Posted: 01 Aug 2017 at 5:34pm
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I already have the roller heads. Short mohair so I will try them. I am planning to get a laminating roller as well. I was hesitating over one for a while when ordering supplies and kind of regretting not getting it now. I understand that a heat gun will get epoxy off almost any metal tool? The tape went around my fillets well. The issue was just getting all the overlaps to lay down flat. Really appreciate the advice Steps. |
Posted By: MikeAqua
Date Posted: 02 Aug 2017 at 7:55am
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Some epoxy comes off (before curing) with white vinegar. When I have watched professional guys using those ribbed rollers they regularly clean the roller in a little tub of solvent. |
Posted By: Steps
Date Posted: 02 Aug 2017 at 9:57am
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I understand that a heat gun will get epoxy off almost any metal tool? Bottom line ALWAYS clean you tools etc BEFORE it goes off.. once it goes off, its time rip into the staff that ignores the most basic of instructions. Be it isophalics, araldite glues, 2 pot paints glues or the most tuff of them all Epoxy.... Once its gone off throw it away. |
Posted By: OneWayTraffic
Date Posted: 04 Aug 2017 at 9:11pm
Just as well I am working for myself then.  You've saved me either a bit of money or a bit of time. Cheers. I have cut out the rest of the glass tape for the inside and set it out so I can get the right pieces in the right places. I have also got some 200g woven for the inside soles cut out. The woven cut very easily with scissors. With the biaxial I measured it out on the cardboard, then held it tight with a metal ruler and cut with a fresh, sharp box cutter. Worked a treat but hard on the blades.
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Posted By: OneWayTraffic
Date Posted: 04 Aug 2017 at 9:12pm
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Posted By: OneWayTraffic
Date Posted: 05 Aug 2017 at 6:34pm
Glassed most of the inside today. 400 biax on seams and 200 woven on the floor to protect against gumboots etc. went a bit small on a couple of fillets so might have an air bubble or two when it sets up.  Still a rough area or two on the seams but a bit better than before. I'll cut out the hanging threads etc tomorrow. |
Posted By: yknot
Date Posted: 05 Aug 2017 at 6:46pm
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Looking great ------------- Those that say it can't be done are being overtaken by those doing it. |
Posted By: smudge
Date Posted: 05 Aug 2017 at 7:21pm
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Crikey OWT, this things going to be finished before I get round to mowing my lawns! Looks good! ------------- Best gurnard fisherman in my street |
Posted By: OneWayTraffic
Date Posted: 05 Aug 2017 at 8:59pm
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Haven't mowed my own lawns for weeks. Being a school teacher is a great advantage. I was able to get the basic structure put together in a two week holiday. The rest of it has been after school sanding, and two weekend days of work. The cloth took much much less time and epoxy than the biaxial tape. I just poured it on and used a spreader. The tape was a lot more labour intensive to get it wet through. Still a couple of bits that I think might not be properly wetted out, but as this thing is completely overbuilt that shouldn't matter very much. At the moment my plan is to have the boat in the water by the end of the term three holidays. I may be doing bits and pieces of finish work in the New Year. My son used a paint roller to get the initial coat of epoxy on the wood. Worked better than a brush. The tape I wet out mainly with a chip brush. Best tool for the cloth was a plastic spreader.
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Posted By: OneWayTraffic
Date Posted: 06 Aug 2017 at 6:58pm
Glassed the front compartment today. Biax 400g over the whole bottom with overlaps it will be a lot more in places. Should be bulletproof. This will be anchor and chain storage along with other bits and pieces. 
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Posted By: Don18025
Date Posted: 07 Aug 2017 at 1:54pm
| Looks really great Oneway....thank you for sharing your journey with us. |
Posted By: OneWayTraffic
Date Posted: 09 Aug 2017 at 11:58pm
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Plan for this weekend is to sand/grind off one massive airbubble that I missed in the forward compartment around an inside corner. There's two layers of biax there so there should be good glass underneath. If I'd seen it I could have laid it flat easily before it cured. I'll also sand over the inside transitions and make a start rounding off the outside for glassing. |
Posted By: OneWayTraffic
Date Posted: 12 Aug 2017 at 7:14pm
Found a couple of other air bubbles in the inside glass. Ground them out and will go over with epoxy putty probably. Rounded the whole outside of the boat also. Used a multi tool to get the Rough shape and finished with paper. The renovator brand grout rasp made short work of the job and was less than half the cost of Bosch. No one will ever know I didn't stitch perfectly now!  
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Posted By: OneWayTraffic
Date Posted: 19 Aug 2017 at 7:39pm
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Glassed the whole outside today. Started to rain so had to carry it inside half done. A length of 400g biaxial on each seam then 200g over the bottom. Once wet out I mixed up some epoxy fumed silica thickener and 420 aluminum powder. Looks like a very thick paint. Used over a litre. It self levels well but I put some plastic over it afterwards. Not sure if that was a good idea. I'll find out in the morning. I was wondering if any experts knew if I can get a chemical bond with west system fast 24 hours later?  
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Posted By: OneWayTraffic
Date Posted: 19 Aug 2017 at 9:22pm
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Pretty sure the plastic was not a good idea. I'll pull it when still green and go over with another coat. Oh well, just a bit of time and money. |
Posted By: OneWayTraffic
Date Posted: 19 Aug 2017 at 11:00pm
Pulled off the plastic and went over with some more epoxy. The color is due to the 420 aluminum powder. Better now but not half as smooth as it was before I had my bright idea. I'll wait for a full cure and try to longboard it. Then another coat and done. 
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Posted By: OneWayTraffic
Date Posted: 20 Aug 2017 at 5:21pm
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Skeg on and another coat on the bottom filling in some of the places that didn't get much of a coating. There is now up to 2mm in places, over the 200g woven and 400g biaxial on the seams. The Westsystem 420 Aluminium powder mixes in quite well, and along with a bit of silica makes a paste with quite good self leveling properties. It also protects from UV and hardens the surface. How much so I will need to run into some shingle beaches before I know. Looking a bit wavy and rough though. It was ten times nicer before I tried that plastic. If anyone wants to try plastic or peel ply then make sure you have help getting it on really smooth and without wrinkles. I am not sure at this stage if I will do much to fix it, I will have a look once it is all cured hard if sanding it smooth with a longboard is something I want to do. As it is it will be out of sight most of the time and will protect the bottom very well I may just leave it. I will try to improve the look of the sides though. Need to put on a rubrail then mask off a line and fair/smooth and paint above it.  
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Posted By: Steps
Date Posted: 21 Aug 2017 at 8:49am
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A DA or belt sander. |
Posted By: OneWayTraffic
Date Posted: 21 Aug 2017 at 12:48pm
| The more I look at that photo the more it bothers me. I don't have a belt sander but may be able to borrow one. Otherwise I can do it by hand I think. I do have a Bosch multitool with sanding discs. |
Posted By: Steps
Date Posted: 21 Aug 2017 at 1:58pm
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Is the surface slightly tacky? no styrene in the mix? If so, the intial mission will be getting that tacky surface off.. it will fill sand papers etc bad. And if weigh down heavy, you can force the tacky surface stuff into the sanding groves making getting rid of the tacky stuff even bigger job Either way I would seriously consider lighty hit with disc sander, 40 grit, and only go as far to leave the lower 'grooves' Then hit with DA or belt..80 grit, again dont take out he very low groove, just have the sand paper scratch but not remove them. Then DA, or belt wet sand or even along board, 80 as above.. then 120.. just see the low pionts, then 180 and finish 220/ 240 The 180, low points just visible here and there, the 240 finishes off taking any partly remaining scratches from the 80 grit. |
Posted By: OneWayTraffic
Date Posted: 21 Aug 2017 at 4:20pm
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Shouldn't be anything like that. Might be an amine blush, if so I'll wash it off before sanding. The tech teacher at the school I work at will lend me a belt sander. I'll try to do as you suggest, but also adding another coat once the highs are off and the surface keyed up. |
Posted By: Steps
Date Posted: 21 Aug 2017 at 4:39pm
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I think your 1st coats was enough.. if didnt have wrinkles/ plastic on it. That would just needed a good block off , not going thru, a hi build epoxy undercoat , blocked off and finish coat. You now have 2x thickness , lot extra weight...think of the 2nd coat as a hi build under coat that needs blocking back. So another coat should not be required, and maybe a hi build should also not be required before final coat. What ever you do.. when you see the layer to the underneath get thin, do not sand further. You can not sand out a hollow, but you can build it up with a high build undercoat .. If have not gone thru... thin is ok. These basic methods/ principles apply to prepping a high end show car for the perfect mirror finish. And plastering a wall or ceiling perfectly flat so imperfection dont show up when light is cast down the surface Yes have done both more than once in my time using a disk sander(if required) then DA and/ or belt sander, then finish with a long board is the fastest , quickest, least effort, to creating the perfect finish.. and the difference between 'acceptable' and perfect is only a few minutes work. Yes a few minutes.... |
Posted By: Don18025
Date Posted: 21 Aug 2017 at 6:14pm
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Oneway, I m trying to work out why you applied that thick heavy home made coat on your hull. First rule of dinghy building, build it light. you added enough extra weight with the glass cloth. Then you put the thick stuff on. Your boat is not going to be a super yacht rocket ship so does not need extra protection or the finish that may have promised Second Rule; use a good oil based house paint over a useful undercoat - job done. I have applied Resene undercoat for fibreglass over ply and then an exterior top coat, has lasted 12 years and does not need a repaint. An observation; that skeg looks like a waste of time, first rock you hit will break it of. It will make the dinghy weather cock or end up being pushed by the current at the stern. A skeg tapering forward about 2/3rd length of the hull will strengthen the keel area and should give good direction control. 20mm high near the bow and 80 to 100mm high 300mm forward of the transom. You have done really well so far so get the finishing right and it is very simple.
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Posted By: viscount
Date Posted: 21 Aug 2017 at 7:23pm
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Use a DA with 80 on it and sand it back smooth, you needed a good squeegee to put plastic or peel ply ------------- Calling fishing a hobby is like calling brain surgery a job - Paul Schullery |
Posted By: OneWayTraffic
Date Posted: 21 Aug 2017 at 8:04pm
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Don I should probably explain a bit. The boat will be mainly used for crossing salmon fishing rivers and trout around lake edges. The bottom will be getting a bit of wear and tear, as the boat will get dragged up rocky or sandy beaches on a regular basis. If I was using it to go to a mooring I wouldn't bother.
The info sheet for Westsystem 420 aluminium powder says this: Aluminium powder is added to increase toughness and to shield the substrate from ultraviolet radiation. Adding between 5% to 10% of 420 Aluminium powder by volume will provide protection from ultraviolet light in areas which are not protected by other coatings. For this reason it is often used as a base for subsequent painting. The additive will also substantially increase the hardness of any coated surface. That sounded like goodness to me. American builders usually use Graphite powder instead for scuff resistance and UV protection. I did not really want to paint the bottom as I figured I would be scratching it too much. I do not mind if the coating is a little thick. Weight will not be a major concern for this dinghy. The total weight (30-40kg) will be well under the recommended load (100kg) of the beachmaster dinghy wheels I intend to fix to the back. The extra use of epoxy is another thing, but I bought 12litres when the BOM said 6 would be enough (for a careful builder keeping material use to a minimum.) No matter how much I waste, I expect to have some left over sitting unused until the next project. Possibly the coating is overkill, but I would rather overkill than underbuild. I never seriously considered a fairing cream for the bottom as some use as I wanted it to be as tough as I could make it. If I had access to and there was an easy way to coat it with UHMWPE I would have used that instead. I don't mind sacrificing looks for utility. I am aiming for a practical finish, but I don't want it to look like it was built like somebody who doesn't give a damn either. Does that make sense? When done I want someone to look and think that it fits perfectly the use to which I intend to put it. The skeg isn't finished yet. I stuck it on quickly in the morning before going out with my family. I was given 20minutes (timed) to work on the boat and wanted to get it on while the epoxy was still green so I could get a chemical bond. I used two layers of 20mm pine. The plans state a rounded triangle 450mm long and 80mm high near the keel. The designer definitely knows his stuff. I intend to cut it down at the front and possibly use the cutoff bit to build it up at the back. With my tools at home that was easier for me to do. I don't want to sound defensive here; your constructive criticisms are truly appreciated, and preferred to pats on the back!
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Posted By: OneWayTraffic
Date Posted: 23 Aug 2017 at 12:36am
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I had a wee play with the skeg today. I could lift the boat with it. Epoxy has a tensile strength of 50MPa. That's roughly 5kg per square mm. Multiplying by the surface area of the skeg and the surrounding glue fillet and that's several tonnes! Should stay put. I do need to pretty it up some and curve off the ends. I was also thinking about a bit of Aluminium strip on it, not sure if that's worth the time and bother? |
Posted By: OneWayTraffic
Date Posted: 24 Aug 2017 at 10:24pm
Today after work I cut out the rubrail from the original sheets of plywood. I used the hull panels as a template before stitching so the strip followed the hull perfectly. Not my idea but works a charm. Thin coat on the ply then thicker coat to bond. Used leftover glue mixed with west420 to feather in the sides a bit. 
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Posted By: Don18025
Date Posted: 25 Aug 2017 at 7:51am
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Oneway, that looks a really smart dinghy. Like the sheer line. Really good effort to date |
Posted By: OneWayTraffic
Date Posted: 25 Aug 2017 at 8:45am
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Plan for this weekend is to sand down the bottom and stick on the second layer of rubrail. Next weekend I am hoping to splash it in Pegasus lake to test stability etc. |
Posted By: OneWayTraffic
Date Posted: 26 Aug 2017 at 7:35pm
Used my sawmax and multitool to cut down the edges of the rubrail then over both sides with a round off router bit. Sanded the bottom for a couple of hours at least. Rounded off the skeg and coated with epoxy. The pieces of wood you can see I'm bonding to the back will be for the beachmaster wheels. I'll attach the wheels to a ply bracket glued to that wood. Should be better than drilling holes in my boat, letting water into a sealed compartment.  
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Posted By: OneWayTraffic
Date Posted: 27 Aug 2017 at 7:29pm
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After sanding the hull down both by hand and with the multi tool I put another coat on. Covered sides and bottom, special attention given to the bottom of the rubrail which got two coats of neat epoxy then brushed over with a thicker mix. The finished product is much better than last week. I may paint the bottom or I may not.   
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Posted By: OneWayTraffic
Date Posted: 27 Aug 2017 at 7:34pm
| Time to consider paint. A google tells me that many speak well of dulux weathershield. However that is an oil based paint overseas while in NZ it's a water based acrylic. Aside from a exterior house paint I was also looking at Toplac. Price is similar from marine deals. I won't need to prime; the epoxy does that but I am not sure if I need an undercoat or not. Toplac says nothing about undercoating that I can see. |
Posted By: OneWayTraffic
Date Posted: 29 Aug 2017 at 9:15pm
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Beachmaster dinghy wheels arrived today. Those things look solid. Nothing like the cheap plastic jobs. 5mm Aluminium frames, stainless connectors and plastic just to keep them seperate. I need to cut a ply bracket for them and glue it to the wooden supports bonded to the back. |
Posted By: MacSkipper
Date Posted: 30 Aug 2017 at 7:39am
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Looking good want to see pic of first fish caught! ------------- Good fishing trip nothing breaks, great trip catch fish. |
Posted By: OneWayTraffic
Date Posted: 30 Aug 2017 at 3:00pm
| I can tell you already that it won't be a tuna or a Marlin. Hopefully I'll get into the salmon as Christmas nears. |
Posted By: MacSkipper
Date Posted: 30 Aug 2017 at 4:10pm
------------- Good fishing trip nothing breaks, great trip catch fish. |
Posted By: OneWayTraffic
Date Posted: 02 Sep 2017 at 11:51pm
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Put on a couple of cleats for gluing the rear seat, cut out the mid seat frame side and glued that in as well. I may or may not do a bit more on it tomorrow and will post pictures then. Any thoughts about outboards? Better weight under 20kg, which leaves one of the 2hp outboards. 2 or 4 stroke makes little difference either way. Was favoring a Honda 2hp due to the lack of a waterpump but I have heard horror stories about corrosion in the salt for that one. Apparently it's a lawnmower engine with too many mild steel parts. That leaves the Suzuki 2.5, Tohatsu 2.5 or 3.5 2 or 4 stroke, or the little Yamaha 2stroke 2hp. Anyone got any experience with any of these engines? |
Posted By: Dagwood
Date Posted: 03 Sep 2017 at 7:54am
| Must be a serious number of those 2 stroke Yamahas out there being abused as tender outboards. We had one when I was a young fella some 30 years ago and they look unchanged. Cheap, simple and reliable. |
Posted By: Tagit
Date Posted: 03 Sep 2017 at 8:40am
| If you want toughness as well as an excellent finish I would suggest using Perfection rather than Toplac. Perfection is super hard and about as tough as a paint finish will get. Will take probably one more coat to finish than Toplac as it applies in thinner coats so a little more work up front. |
Posted By: OneWayTraffic
Date Posted: 03 Sep 2017 at 9:40am
| Already ordered Toplac. My main concerns with the two part paints came down to smell, cost and the fact that they would highlight every imperfection off the finish |
Posted By: Tagit
Date Posted: 03 Sep 2017 at 10:06am
| I have used Toplac and Perfection. I love Perfection because of it's toughness but Toplac is easier to use and like Perfection does a great roll & tip finish if that is the plan. |