Josh's ski building.

[a.badner]

right inbetween acutally. its 9.
roughly calculating ( didnt want to pull out my calculator)

perimeter= pi(diamter)
=3(6'')
=18

layflat of a circle = diameter/2
= 18/2
= 9

[Josh]

I think i'm best to use a cat track, otherwise the hose may push on the sides as well as the top, this could cause the base to become concave, (if you understand what i'm trying to say.) The cat tack would mean the base would be perfectly flat which is what i'm aiming for I think an al. cat track will probably be the best, so assuming it isn't ridiculously expensive i reckon i'll go with that.

Also, the firehose is just over 9" when flat.

Press looks pretty sweet by the way.

cheers! hopefully it will perform as well as it looks

[a.badner]

you will be disapointed with al. its pretty expensive.
imo you dont need that track
but its your press. not mine.

[EricW]

I think you're right by using a track. nice even pressure. I could see the top corners buckling with sidewalls.

[krp8128]

you will be disapointed with al. its pretty expensive.
imo you dont need that track
but its your press. not mine.

Keep in mind this post is from a 15-year old who hasn't built a ski yet. Read his journal, it is very "interesting".





Badner, stop dumping on others. You refuse to take advice in your thread, and it is clear that you lack the experience to give it to others.

[skidesmond]

I think i'm best to use a cat track, otherwise the hose may push on the sides as well as the top, this could cause the base to become concave, (if you understand what i'm trying to say.) The cat tack would mean the base would be perfectly flat which is what i'm aiming for I think an al. cat track will probably be the best, so assuming it isn't ridiculously expensive i reckon i'll go with that.

Also, the firehose is just over 9" when flat.

Press looks pretty sweet by the way.

cheers! hopefully it will perform as well as it looks

Use a cat track for the reasons you stated. Lots of people are using aluminum, but a wood cat track will work also.

[Josh]

Got some more stuff done today, mainly the top mold. Also I've ordered the materials for the first pair of skis

Unfortunately boardbuildingsupplies had no VDS so i have a few questions, firstly how important is the vds? (actually i think i know the answer to this, very important )
Secondly does anyone have any ideas on where to source the VDS from (anyone got a few spare meters kicking around i could buy?)

Hopefully i'll get a lot done this weekend. Like the template for the ski, and, if i get the metal, the cat track

[Richuk]

Davide doesn't use it, or at least, he hasn't used it and not had too many issues. You'll appreciate that VDS is generally considered to be a gasket around the edge set, a shear layer between composites and a subtle vibration dampening layer (I may be on my own on the last point).

If you need a few metres PM me. I think the manufacturers address is kicking around the website.

[Josh]

Back again A few updates, firstly i've put the clamps on the firehose and added the valves, as well as a pressure gauge so i know what i'm pressing at (you can't always trust those compressors ) I looped the ends over a metal bar and clamped together with a silicon gel used on the inside. It's been inflated to 60psi with no problems, and no obvious leaks


Bladder by josh's ski building, on Flickr[/img]

The pressure gauge is just out of this picture.
I have also bolted together and sanded the top and bottom molds. I used 1/2" bolts, and it seems to be held together nicely.


Bolted mold by josh's ski building, on Flickr[/img]

So i then decided to see how it all looked in the press


Top + bottom molds by josh's ski building, on Flickr[/img]

I've also decided, unless someone disagrees, to not use vds for the first pair. I reason that they seem to a cause of delaminations, and are just an extra factor for lay-up. But please let me know if you think differently.

Meanwhile i have used Dan Graf's excellent software (sno-cad) to design the first pair of skis. I intend to go for a 124-78-110 shape. Pretty narrow for most of you but i don't seem to get to ski the bottomless powder very often besides, i can always make another pair!!

Next up, it's the cat track, having seen the price of al. i'm going to try one out of wood first, but if it doesn't work i'll have to fork out for some Al once that is done i think i'm ready to press providing the materials arrive.

[skidesmond]

Good progress! If you have the VDS use it. It's not that expensive. It provides that shear layer between the metal edges and FG. If anything it should help in preventing delamination.

[G-man]

Hey Josh,

Your bolt set-up at the ends of your bladder scares the crap out of me. Over time, the fire hose could work it's way free of the angle iron pieces, and it could release with a lot of force. Could be ugly, even deadly. I suggest that you bolt through the steel and the hose in at least 3 places on each end. Sorry, I don't mean to pop up just to be critical, but I have just a few minutes to post. If enough new ski builders got the idea that your method was an okay way to seal the end of the hose, sooner or later, someone would get hurt.

Best regards,

G-man

[Josh]

Hey Josh,

Your bolt set-up at the ends of your bladder scares the crap out of me. Over time, the fire hose could work it's way free of the angle iron pieces, and it could release with a lot of force. Could be ugly, even deadly. I suggest that you bolt through the steel and the hose in at least 3 places on each end. Sorry, I don't mean to pop up just to be critical, but I have just a few minutes to post. If enough new ski builders got the idea that your method was an okay way to seal the end of the hose, sooner or later, someone would get hurt.

Best regards,

G-man

Thanks for the advice, this is exactly why I've posted this topic, so that i've got an extra few sets of eyes checking everything will be ok From what i understand you're suggesting that i bolt through the hose as well as at the end of the angle iron, and this is to prevent the angle iron from slipping off of the hose. However i believe my pictures are not clear.

I did consider this problem when designing the clamps for the hose, and in order to prevent the metal from slipping of the end i added a steel rod in the fold of the hose so that the angle iron can not slip over the end of the hose. This picture shows what i mean.


Hose design by josh's ski building, on Flickr[/img]

Hopefully this is clear enough, as you can see there is a steel rod in the fold, i realize this is not visible in the pictures i provided but think it makes a big difference as it should stop the clamp from being able to slide off the end of the hose. With this considered do you believe the hose is safe or should the extra bolts through the hose be added as well?

Thank you very much for the advice, if i can work out how i will replace the current pictures to avoid misleading new ski builders.
Thanks again.

[G-man]

Thanks for that clarification Josh. As you know, we're working with some huge pressures with our pneumatic presses, and we've seen some pretty frightening set-ups in the past. We never know who's watching and 'learning' from the stuff we post. Myself, I'd probably still throw a couple of bolts through the iron and the hose... but, that's just me. They don't call me scar-face for nothin'.

G-man

edit: just re-read and saw where you plan to add the bolts.