Shaping and glassing a stringerless blank

[HungryPete]

it will definitely look weird and will certainly not be the next big thing but if I glass it heavy it should hold up and could be fun to ride. I don’t see any reason why the foam should keep expanding after a few days have passed like someone said. I’ve seen sculptures molded from that very same batch that were cured under pressure and they still look just like they are supposed to.

 

the stuff I used was out of date, measured measured poorly and mixed in containers containing traces of other chemicals by the way. could have been done better for sure. probably should have worn a mask but don’t feel funny… yet.

 

pete

 

[kensurf]

My appologies Hungrypete

I didnt know you were in a far away place and had limited supplies

I now say,,, have at it and make it happen .. show us plenty of pics please

[BgSurfer]

I was being serious.  If this is what you really want to do, don’t give up!  The other blank manufacturers didn’t get where they are by giving up.

[chippy61]

this could be an interesting thread ,

 

 I can't remember a 'blow my own foam' thread here before !

 

  you are from norway ??

 

  maybe you could visit 'havaard' , he's from there too , and a moderator here ...he might enjoy meeting another norwegian swaylockian , and maybe he could tell you where HIS blanks come from ?

 

  how is the water temperature there at the moment [your summer] , 'hungry pete' ??

 

    cheers

 

  ben

[resinhead]

So your telling me you have no EPS foam...you don't have boat docks in Norway, or no construction EPS foam?  You white guys are strange.

 

You are a freak...and you have too much time on your hand.  Get a job.

 

No that's out of the way.....wear a mask, gloves etc.  Take lot's of pictures so we can make fun of you.  we will laughing with you not at you..I promise.

 

 

[the_rising_tide]

After watching that hilarious part from Barefoot Adventure, I definitely want to see this thread continue.

PLEASE post pictures. Thank you.

[PSH]

Jeg har trua. Få til dette, gjør det billig og selg blanks til oss andre nordmenn!

[Bud]

@$1

Jeg har trua. Få til dette, gjør det billig og selg blanks til oss andre nordmenn!

“I have faith do this makes it cheap and sell blanks for us Norwegians”

[astevens]

Yeah you might have to do a video…looks like that foam starts going FAST!

good luck…I think you’ll need alot of it!

[chippy61]

classic  !

 

  is that good ol' 'babelfish's translation , Bud ?

[AaronFromArizona]

This is my first post with much respect to the people who post here the wisdom and experience is priceless.

 

So just like HungryPete I am totally new to surfboard shaping and have only made one HomeDepot styrofoam with homedepot garage floor epoxy board(against much advise on Swaylocks). The board was only to be used in our river tied to a rope trying to surf a rapid. The river board was mainly to keep my real longboard from getting dinged up. It works just fine as a total beater in a rocky river and it was good experience with fiberglass and epoxy.

 

I totally understand I can buy a blank for less cost and hastle and have
a good start on a real board, but its more about the challange of
trying something new(a $70 blank costs $165 to ship to AZ, I can get the pour foam for about $50 and the
material to make the mold is $20 or less)

Anyway, I am a sprayfoam insulation contractor and have had the thought of building a molded foam blank. Our high heat sprayfoam expands way to fast for this application(see any youtube vid on sprayfoam insulation).

 

Like Hungry Pete I was thinking of using pourable foam in a mold. The plan is much like HungryPete’s, make a plaster mold of an old board and use pour foam(2 pound) the only difference is that I plan to make the mold in 2 halfs.

The mold will be built as if you took a real blank and cut right down the stringer and you had two vertical halfs, then you would pour the foam down into the mold from where the stringer was individually for each side.

My theory is this method does a couple things:

-It allows a you to mix up a smaller more manageable batch for each side.(downside is each side may be different?)

-It allows you to mold each side of the old board seperately so you dont have to worry about prying the mold off and damaging the old board.

-It allows room for the foam to expand up as it fills the cavity so there is a place for the extra expansion to excape

You could then trim the excess foam along the stringer line and have two halfs of a board.

You could then use epoxy to laminate the two halfs back together. (ie epoxy stringer)

Perhaps this experiment will be a total flop? It does seem like everyone thinks its a bad idea and wont work but everyone wants pics and vids.

If it works it could be a decent alternative for remote surf spots (like norway).

 

Its like my 2 1/2 yr old boy who thinks he can do something out of the norm and I always know it wont work but half the fun is the time spent trying.

HungryPete any more progress or Pics?

If I do my experiment I’ll post some pics or a video.

 

[jimthegenius]

Walker Foam had a 12’ billet blank they made, it was poured in halves, jointed on one side each and then glued together, Velzy was using this method for the 12 footers I was shaping.

What was the problem ? the 2 halves not being from the “exact” batch, cured at different rates, a lot to factor, humidity, heat, mixture, but after shaping, one side of the blank would draw the otherside to it, with the centerline becoming as much as 1-1/4" out of alignment and it just kept going like the Eveready Bunny. A very expensive experiment for Velzy and Walker to toss in the trash can.

 

[AaronFromArizona]

Jim,

Thanks for the info/experience about this method. That would make a crazy board. 2part 2pound foam is a closed cell foam that continues to off gas over time so this could be a problem, perhaps having a vent plug on each side of the stringer may help. Or perhaps a better method for making the mold. 

I’ll let you know if I give it a shot.

Thanks

[pirate_agenda]

@$1

This is my first post with much respect to the people who post here the wisdom and experience is priceless.

 

So just like HungryPete I am totally new to surfboard shaping and have only made one HomeDepot styrofoam with homedepot garage floor epoxy board(against much advise on Swaylocks). The board was only to be used in our river tied to a rope trying to surf a rapid. The river board was mainly to keep my real longboard from getting dinged up. It works just fine as a total beater in a rocky river and it was good experience with fiberglass and epoxy.

 

I totally understand I can buy a blank for less cost and hastle and have
a good start on a real board, but its more about the challange of
trying something new(a $70 blank costs $165 to ship to AZ, I can get the pour foam for about $50 and the
material to make the mold is $20 or less)

Anyway, I am a sprayfoam insulation contractor and have had the thought of building a molded foam blank. Our high heat sprayfoam expands way to fast for this application(see any youtube vid on sprayfoam insulation).

 

Like Hungry Pete I was thinking of using pourable foam in a mold. The plan is much like HungryPete’s, make a plaster mold of an old board and use pour foam(2 pound) the only difference is that I plan to make the mold in 2 halfs.

The mold will be built as if you took a real blank and cut right down the stringer and you had two vertical halfs, then you would pour the foam down into the mold from where the stringer was individually for each side.

My theory is this method does a couple things:

-It allows a you to mix up a smaller more manageable batch for each side.(downside is each side may be different?)

-It allows you to mold each side of the old board seperately so you dont have to worry about prying the mold off and damaging the old board.

-It allows room for the foam to expand up as it fills the cavity so there is a place for the extra expansion to excape

You could then trim the excess foam along the stringer line and have two halfs of a board.

You could then use epoxy to laminate the two halfs back together. (ie epoxy stringer)

Perhaps this experiment will be a total flop? It does seem like everyone thinks its a bad idea and wont work but everyone wants pics and vids.

If it works it could be a decent alternative for remote surf spots (like norway).

 

Its like my 2 1/2 yr old boy who thinks he can do something out of the norm and I always know it wont work but half the fun is the time spent trying.

HungryPete any more progress or Pics?

If I do my experiment I’ll post some pics or a video.

 

 

I have watched my local blank manufacturer (who has been doing it for close to 50 years) pour a few. He still gets a couple wrong every now and then. It is a very sensitive process:

• You’re going to need more than a “plaster mould” the guy i have watched has 2 types of moulds - 1 type is made of about 6 inch thick reinforced concrete the top piece is hinged with levers etc to pull it shut. The other type of mold is thick fibreglass reinforced with heavy steel, with about 6-8 clamping bolts for a 6 foot board

• You need to get the mix of the pour foam exactly correct or the blank will either be too heavy, too soft, or have a very hard crust on the outside and be like butter on the inside

• after he pulls the blanks out of the mold - they go into an incubator style oven room with the temp and humidity set at an exact setting. Not sure how long they stay in there, but if they cure in incosistent temps and humidity they will shrink or expand.

 

My guess is that your $20 mold will explode into a thousand pieces. My second guess is that you could probably by a container full of real surfboard blanks for what it will cost you to se up the whole process safely and properly. 

If you’r too tight to pay for a real blank go the eps slab route.