50 years 70kg, basic freeride level, small lake light gusty wind, 10 to 15 medium wind knots but 5 in lulls and 25 gusts. Actually i ride an home made hybrid race board, 290x72x180l daggerboard step tail, and try some freeride to slalom boards. For my level longer not to wide with volume work best, best one i find was an old ahd diamond race 72. Main sail simmer 2xc 7'8.
As a hobby builder i want to build a new one, i modify my template up to something that look right to my eyes, 270?72. Volume would be around 150l.

I build blank with leftovers from another projects. Center part is 3 layers of 18kg/m3 eps glueded with pu glue and epoxy mastic, side are .

I shape by hand, V bottom, mid rails. I seal foam with a lightweight epoxy spackle, add chinook power box and 10cm wide 250gr ud glass strip on bottom

Looking good . I use expanda foam to fill the top of the box. What is with the cork inlays?
Love a board build. What glass, carbon, sandwich are you going to do? vacc bagging?
But most important...., .... is that you're neglecting your lawn. Could do with a quick mow.

what is stopping the box from rolling? I'd install after all the sandwich... or is there a lot of glass around it and a lot going over top? Curious if you have done that install method previously...

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Imax1 said..
Looking good . I use expanda foam to fill the top of the box. What is with the cork inlays?
Love a board build. What glass, carbon, sandwich are you going to do? vacc bagging?
But most important...., .... is that you're neglecting your lawn. Could do with a quick mow.

Don't forget the edges.

I hand lam bottom with 100gr/m2 ud glass - 217gr/m2 biax carbon - 100gr/m2 ud glass finish with lightweight epoxy spackle, resin tinted.

No sandwich on bottom, only on deck.
For the box i do some sandwich each side of box to stiffen this place. I use 2mm cork fill with epoxy spackle with carbon under, i will add couple layers of carbon on top. I do the same on my windsup i use with 52cm fin and I do many foil rails installation like this with no problems, hope it will go well this time too...
I sharp edge at end of build, rounded it a bit first because i hand lam. I don't vacuum bag lam, i keep it low tech, cheap and simple for me. This way i know what i do and where i go. For sure not the best weight/strengh/stiffness ratio but for me en acceptable compromise of durability/performance/price. Hope to finish around at 10 kg.

Awesome, great job and inspiration for us home builders. Please more pics and info.

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Not so much time to work on the board, i just lam layers of 125g/m2 glass on nose and tail with epoxy tinted black. I do a sandwich with cork and biax carbon for mast track and cut carbon biax 217g/m2 renforcement that will go under cork.

Today, i prep glass, 1 layer of 125g, with 15cm cover at center, then lam with carbon and cork over then go in the bag under vacuum.

That is one sexy shaping / glassing room.
I hope you're not neglecting your lawn.

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Imax1 said..
That is one sexy shaping / glassing room.
I hope you're not neglecting your lawn.

No don't worry. I take care and cut it again, some years ago you never havd to cut lawn in october, but it was before....

Nice room!

It's time to continue:
Flush sanding edge of cork. It's fast and easy if you take care to let cork go up to rail line when bagging. I also like to final sanding upper rail foam a bit more when shape so it look with fiber laps and cork flush.
Set inserts with carbon and epoxy mastic. First at each plug i remove some cork to let thickness of 2 layers biax carbon 217g/m2 fiber laps. Finaly sand flush.

Cork seal with epoxy micro slurry then sand, ready to lam:

Looking splendid

Very neat work

Hand lam deck with one layer of biax carbon 217g/m2 finish with tinted epoxy spackle.

Sand bottom and polyester gloss

Looks great. Do you use polyester gloss because it flows better ?

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Imax1 said..
Looks great. Do you use polyester gloss because it flows better ?

Yes for me polyester (isophtalic) top coat is easier to use than epoxy for a "no problems" finish. Flow better, no fish eyes, no blemish, you can clean brush well and use it again and again, higher barcol hardness that is easier to sand with right process, cheaper. I use it as really thin finish coat, like a varnish, not hot coat, on a fully cured, well sanded, 80 grit, phenol free waterproof epoxy filler coat. I do many boards like this with no problems, only spider web when board ding. If i have right equipement i would spray a thick pu 2k finish instead.
I am a garage builder, i keep a simple predictable process with easy to find localy reliable materials.
This way i know where i go and i don't have my friends knock the door for repair everydays like when i start build board with polyester. I hate repair boards.

Today i finish the board. I calculate volume more accuratly with many measure, 155l. Weight 9.7kg not so bad for this kind of board and tech. Probably can be build less strong with no problems. With some optimization in process and lay up can be a good 1kg less without to much strength lost.

A thing of beauty

Love the finish. Did you use a squeegee to apply spackle. Have been contemplating trying a sponge to see if any difference to finish.

Yes i use a squegge. I mix 1 volume epoxy and tint then add about 1,5 volume glass microsphere and 0.5 volume colloidal silical. Whipped cream concistancy. Sand then top coat clear.
I try more or less runny consistancy with brush, roller, sponge with no success, perhaps with lot of mix it could work.

Looks great, hope it doesn't feel too heavy on the water. What's the approximate costs in materials for the full build?

For weight feeling i ll see but i am use to an home made hybrid race around 15kg. For this size of boards 150/160l freeride 9.7kg is light, all i see are around 11kg. For cost blank is 20e (euro)for center part and glue, sides blank for free. Carbon was 50%discount with glass 140e, resin 60e, insert 60e other consumables 20e. Total around 300e.
If i have to do it again i would start with a 20kg/m3 blank far better quality/consistancy from my supplier with a light stringer. Cover bottom with multilayers standard glass with epoxy/micro slurry, for top keep carbon cork glass sandwich.

9.7 kg for a solidly built 270 cm board is not heavy. I bet it will work good. Well done.

Agree imax.

Takes experience to finish a board off like that. looks great, fun times ahead!

Beautiful!

Can you tell me a bit more about the setting of the mast track? The steps and materials?

Back of mast track is 1280mm from back of board.
Look from my first post it's step by step with material description.

First use yesterday, wind was 5 to 12 kn never grow like forecast. Bigger sail, 7'8 simmer 2xc. Board feel really light and easy to move out and on water. I am used to a 3m 15kg hybrid race.
Plenty float for my 70kg, go upwind really well sub planing, i was worried of that in light wind with no daggerboard, but i seems i have near same angle but slower. I use here a 46cm slalom fins. In every gusts i take planning easily then board fly over water freely. I think i'll progress with this board. Need a bigger sail for that wind...

Awesome board! Glad to hear it work well!

When you glass over the fin box and mast track do you fill them with anything to prevent resin/glass getting down into them in the vacuum bag laminating?