Building a Foam Sandwich Sabre Sailing Dinghy at Home

Matt talks about the process of building a Sabre sailing dinghy at home using foam and glass.

[@johnravensbergen3324]

Thanks for sharing!! Great video

[@felixcat9318]

Thank you for compiling this very interesting and informative video. Your boat looks absolutely gorgeous, and I can only imagine how proud you must be. I'm thinking of a 9 foot folding boat so the longest length of foam will only be 4.5 foot. I originally thought of using marine plywood, but foam, fibreglass cloth and resin are increasingly attractive for the project. It won't be a sailer, just a kayak paddle or outboard motor for propulsion.

[@mattwestland8809]

Hi Felix Cat. When you say folding boat I assume you mean a boat that bolts together in the middle.... or you might be meaning something else.There is a dinghy made from plastic panels with flexible seams which folds up into a flat pack. I reckon 6mm foam would be enough for a 9 foot boat. Cheers matt.

[@llamabob2]

Thank you for sharing your build video!

[@JenkinsBoatWorks]

what a wonderful video. thank you!

[@Antipodean33]

I use an Aussie made epoxy called Bote Cote, water based so no rashes etc and also no amine blush. I built a 17 foot sea kayak 15 years ago that is still in excellent shape and I'm using it to build a fishing boat at the moment. It's a 2 to 1 as well, it's very good and not that expensive

[@antiussentiment]

This is a great product that I use to use. And Bruce McConkey (if I recall?), the owner. Is super helpful if you call with a question.

[@michaelkrochmann7239]

Thank you!!

[@antiussentiment]

Last year I built a 2.4 meter tender for our little yacht using 3mm MDF as a core material. The little boat is light and very strong (has survived a drop off the carry racks on my ute with no real damage). We have a very active Sabre fleet at our club and I've often wondered about building and MDF/epoxy Sabre. I've done a playlist of the building process on my channel.

[@mattwestland8809]

Hi Noisy Andrew , I'd be very sceptical of the longevity of a Sabre made with MDF core. It's great you have built a tender that works. At the risk of sounding critical the only advantage I see for MDF is it's cheap and smooth. Sooner or later when the boat gets a ding or scratch through the glass and you miss it, it will blow. Just leave some MDF in the rain to see what will happen. The stiffness of glass skins over core is a combination of glass weight and thickness of core. 8mm foam makes for a seriously stiff and light hull which is what you need for a fast boat. Yep the foam costs more but is insignificant in the overall cost of a racing dinghy. Ill have a look at your channel. Cheers matt.

[@antiussentiment]

@@mattwestland8809 oh.. and what I didn't mention was that the build up to priming and top coat was about $650. Using MDF means it's so strong that you need a lot less glass and resin than you otherwise would..

[@Antipodean33]

MDF??? I'd never build a boat using that, thats crazy

[@antiussentiment]

@@Antipodean33 go look at the videos. I actually got invited to speak/present at the Armature Boat Builders of Australia. They all seem pretty impressed, especially with the strength and the cost. The video series has a bunch of testing etc for strength and water absorption of laminated MDF if you're interested?

[@Peter_Herrman]

Great video, thanks! What was the first layer of fiberglass you put on the foam before you stitched it all together? Curious what weight and type? CSM? WR? Uni? 16oz? I'm assuming it was pretty thin so you could still bend the panels. And was that glassed side placed on the inside or outside of the boat when you put it together - I can't tell from the pics. I thought I'd heard it should go on the inside, but it kind of looks like maybe you did it on the outside. Really helpful video - thanks again!

[@mattwestland8809]

Hi Peter 200 gram or 6oz plain weave. Put glass on inside first unless the panels have to bend a lot ,like at the bow. Leave glass off in those areas until put together and outside is glassed. On outside I used a 295 gram twill which layer down well. cSM is no good with epoxy. I used Uni in areas inside that needed strength one way.

[@mattwestland8809]

Hi Peter one layer of 6oz on inside of panels. Very front panels should have no glass till they are pulled into shape.

[@neilboardman6640]

great vid. im very interested in the cost and availability of the foam. where in AU do you get gurit corecell m80 8mm and whats it cost ?

[@mattwestland8809]

Hi Neil should be available in all big cities. ……marine shops or fibreglass supplier. Or look on Google for Gurit and their distributor near you. Best luck.

[@PEOdysseus]

HOW DO i SEE YOUR DRAWING PLANS OF HOW YOU MADE IT?

[@mattwestland8809]

Hi PE there are no drawings as such. There are building notes on the Sabre website. The template shapes are available from your state association or a CAD file when you apply for a building number.

[@truongluu9437]

I wonder how heavy it is?

[@mattwestland8809]

It’s lighter and stiffer than a build in 4mm gaboon ply.

[@henrydelport6513]

Matt. Maybe I missed it but wat was the total man hours put in?

[@mattwestland8809]

Not sure. I fiddle a lot so even if I offered a number it would be different to what most people would take. Probably about 20 to 30% more than a ply build due to more glassing ,filling and sanding.

[@michaelkrochmann7239]

Brilliant instructions, thank you! Has anyone build one like that in Melbourne?

[@mattwestland8809]

Hi Michael as far as I know none as yet. Our Tas Association is making plans to build a male jig over which a hull can be built. We have 4 foam boats built by amateurs in Tassie. They have all turned out well. Cheers.

[@nexpro6985]

10:10 80 grams per cubic meter? That would be lighter than Aerogel. You probably meant Square Meter. Interesting vid, thanks.

[@eric99vigne]

At the bottom the hollow it is the Self bailer right?

[@mattwestland8809]

Yep at lowest point which is at aft end of centre case. I put in a second one aft but it’s not needed.

[@mattwestland8809]

Yep

[@nilosantos4862]

The totAl cost between play wood stick and glue and PVC foan cover with 400 grams Fiberglass the last case will be higher. But in terms of weight either?

[@mattwestland8809]

Hi Nilo, with 6 or 8 mm foam and 400gram glass either side it will be stiffer and lighter and stronger than 4mm ply.

[@robertcain3426]

​​​​​@@mattwestland8809I think the foam core laminate will be more rigid but doubt its stronger than ply. I've seen comparison figures which specify either 34oz/20mm foam core/34oz laminate or 9mm marine ply. The marine ply is not as stiff and needs more stringer support than foam. In that spec sheet, the weights of ply verses foam are equivalent. Also, in regard to weight, I was surprised how light your laminate was with only 200g cloth each side. I suspect it would be below recommended thickness. Having said that, the conclusion for me is that the core laminate is more rigid, though perhaps more expensive. Thanks for the video. Cheers

[@DangTue-bo4bw]

How heavy is it? if I can ask.

[@mattwestland8809]

Hull is 40 kg. Just 1kg under weight n

[@DangTue-bo4bw]

@@mattwestland8809 Thank you for your information.

[@dc-wp8oc]

Are we just creating more landfill material? How can fiberglass or any composite material construction ever be recycled? Isn't the world overflowing with products that do not lend themselves to the recycle stream?

[@murrayobrien9192]

FFS mate I don't think building a few Sabre racing dinghies is going to do a whole lot of damage. Maybe you ought to consider the waste from wind turbines. Unrecyclable and defunct after 15 years.

[@cryptoscalpers9603]

talks too much......won't be subscribing here

[@johntuttle9544]

Try turning down the volumne?