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Hi guys! Im posting some pictures of our progress with the mold.

We have almost finished it. It consist on a mix between clamp and neumatic press. We dont have air compressor so we decided to blow air into de hose, close the air valves and then apply pressure by clamping the two molds with the bladder inside to do a uniform pressure.

Here are the pictures until today 24/04/2006

1. Drawing the line to saw the wood

2. Sawing it

3. Sanding the mold

4. Cutting the tubes to clamp the mold

5. Painting them

6. Drawing the holes

7. Drilling the holes

8. Glueing the mold

9. Because of the bad quality of the saw the different strips didnt make a flat surface so we dediced to put a slim metal sheet (1mm thick) but we had a lot of problems to bend it (even with the torch) but finally we got it

10. Cutting the sheet

And this is all at this moment, Ill post you some more pictures when we continue with the process!

Great pictures, I can't wait to see some more. You might want to sand down your mold so the pieces fit together as close as possible be for you attach the metal to the top of the mold. My first mold had some small imperfections that I thought would be covered up with sheet metal like the method you guys are using and the imperfections could be seen as high and low spots in the base. I also used vaccuum pressing so there was not a lot of preassure on the skis in the mold. The high spots can be removed with a base grind, but the low spots are there for good. Even with a few low spots (1-2mm) in each ski they still worked pretty well. I am looking forward to the pictures of your hybrid pneumatic/clamp press, it sounds like a good idea.

nice idea with that combination pneumatic/clamp.

Sounds easy to build. I only built a clamp press. But yours seams to be better!

I am looking forward how it works!

I thought it might be nice to share my build with you all.....

I am just finishing the aquisition phase of the project, just begun the fabrication phase & looking forward with anticipation to the lay-up phase.

Aquisition: I have found that the reasonable and sometimes minimum purchase quantities available from most suppliers will provide for about 5 pairs of skis. The 10M minimum Durasurf from Crown Plastics pretty much set the trend. I sourced the rest of my materials with the 5 pair quantity in mind.

Ski Press:

Steel - $117.00 from a local recycler - 16 in I-beam, 4x5 angle

Castors - $12.00 $3.00 each from Harbor Freight

Fire Hose - Free scrap from work

Air couplings & bladder ends- $? Not purchased yet from Home Depot

Heater coils - $Free salvaged from home converted to gas heat

Thermostat for heater coils - $? intend to aquire one from a discarded kitchen oven.

See this thread for my press design. It is all welded together. Ready for paint. Pictures will be posted in a few days.

Core profiler & ski mold:

I have not purchased anything for the profiler or mold yet. I expect to purchase all the materials for them at the Home Depot. I will be making a big, fairly expensive trip there very soon for lots of dimensional MDF, sheet MDF, and assorted hardware items. I already own the planer & router I will use in these processes. I will need to purchase a couple of specific router bits though. One for the profiling & one for sidewall finishing. The planer is relativly new & shouldn't need new knives for a while.

Ski Materials:

P-tex - $70 (shipped) for 10M of orange durasurf p-tex from Crown Plastics.

Edge Steel - 20 lengths - Snowboard materials supplied the edges, rubber & a 140cm snowboard core i will use for son's skis for $161.30 shipped

VDS Rubber - 70M roll

T-nut inserts - $49.03 - 150 inserts from Camax including 1 lb of the detection powder used to locate the magnetic caps on the inserts for drilling.

Cosmetic Fabric - $6 - local fabric store. Some blank white fabric for my 8 yr old son to draw his own graphics (JEDI light sabers was his latest idea) Orange plaid for one pair. Pink camo for my wife's & oldest daughters.

Core - $??? will purchase from local hardwoods retailer. Maple for sure & possibly some fir or even bamboo if I can get a hold of some.

ABS - $??? Sidewall & tip spacer materials will be purchased from local plastics supplier.

Topsheet $??? 0.010 UHMWPE possibly, wood veneer probably for one pair, and one plastic retailer mentioned something he called flexible PVC. I think that the isosport topsheets are this a flexible PVC. There is a more accurate trade name for the flexible PVC but it seems that I didn't make very good notes on that conversation, so I don't know the proper name. I still have some R&D to do on the topsheet before I decide what to buy. Suggestions anyone?

Epoxy - $75 approx for 5 quarts shipped After much research and discussion with a couple different chemists in the industry I decided on the QCM Epoxies. Resin EHV-0050 with hardener ECA-408 4-1 mix ratio. 40 min pot life but fast cure in heated press.

Fiberglass - $inside deal Vectorply 22 oz and 19oz triaxial E-TLX-2200 and E-TLX-1900

Ski Design: There are some skis which have dimension I am interested in copying. I want to make some PM Gear BroModel shaped skis & some Salomon Pocket Rocket shaped skis. I have some PRs already but am curious how the garage build ski of the same dimensions would ski.

Currently I am compiling some data on existing ski dimensions in order to try to establish some baseline information. Things like taper & turning radius are variables that seem to vary quite alot even within the same ski catagory. I hope to be able to share the data soon.

There are some things like wood species and core thickness that are going to have a significant impact on the character of the ski which I cant gather data on. I am sorting through the ski build on this site as well and trying to draw some conclusions about core geometry that will help me settle on a usable core profile.

I would be interested to hear what conclusions the Kams & Kelvin have reached through their trials.

hose-man. very nice. thanks for posting your thoughts. i'd like to see photos of your press. i'm excited to see your press in action, too, as i'm curious about the strength of the I-beams as you have them configured. keep us posted with your progress...

btw, Little Kam, Kelvin and i have been thinking more about how to make this site more user friendly, as well as figure out a good way to display the work of others. at some point it would be nice to have a gallery that shows off skis made by others. anyway, we'd like to ask about ideas for improving this site and how best to handle showcasing the artwork of others... to keep from running off on a tangent, please provide your comments in the following thread.

Photos are in the Digi camera, just the camera is still at the shop. I probably won't be able to get them up 'till next week, but I'll try for sooner.

Thoughts on the suppliers I've used so far.....

Camax was great except they don't process credit cards, so check must be sent then product will ship.

Snowboard materials was always available on the phone & eager to share information which was very helpfull, but when the order was placed, it didn't ship for a week or so, & even then, I only received half the edges I ordered. Lindsey @ snowboardmaterials.com is a great resource & I understand that there is a source delay on the 84" edges he sells, so don't think that I'm not recomending him, just sharing experience. I will order from him again.

Durasurf aka crown plastics was a really easy transaction. I wanted orange base material & they sold me the color I wanted off of a remnant roll for the same price as black.

QCM was very accessible. I had some specific questions about which epoxy/hardener combo to use & was able to speak to the chemist (Roy) who formulates this stuff and he really educated me about their products. The order was placed two days ago. Shipping was slightly inflated because the hardener carries a Haz-mat label.

gret work hoseman, I'll be following it closely.

I myself am just in the process of pricing out the whole project.

If you would like more info on the Bro Models, I can get it for you. a new, softer Bro in the 177 length is in the works as we speak.

just let me know what you'd like to know

I can also post some information on different wood species and their properties. It's an area of my studies so I have a few pertinent texts.

Howz about core info? wood species & dimensions on both the soft, stiff & super stiff. I'm struggling to get a handle on those factors vs. skiability. Thanks!! -J

Thanks for putting up your build log. Our cores are 12 mm in the middle and have a straight taper towards the tips and tails, which are about 2.5-3mm. There are flat spots in the middle about 20cm and at the tips and tails about 12cms. We basically just guessed on a bunch of these dimensions and it worked out pretty well. It gives a nice round even flex, and is on the soft side, compared to something like the teledaddies. I would like to try different core profiles, but haven't had the time.

-kelvin

so there's the ski press frame. All the welding is not yet complete, but all the parts are attached. The salvage I-beam are of unequal length, and the castors are recycled from another project so it is a good thing that looks don't matter when it comes to ski press frames.

man, all of these new frames kick my frame's ass. is it for a pair of skis or just one? i like the idea of having a press raised higher off the ground. i didn't realize until now that I have to walk around like a gorilla to use my press.

The I-beam is 16" wide, so the usable width inside the frame is about 15". I anticipate pressing a pair at a time. I have two short pieces of fire hose, but one of them may be a little too short. If it is, then I may only press one at a time until my Fire Dept has more to "dispose of".

very nice hoseman! thanks for sharing...

I've been charting ski dimensions in excel in an effort to help me decide what dimensions to shape my skis. I've compiled as many skis as I feel necessary for the data I'm after. Since I don't have anywhere to post excel file for you all to use, I will email it to K, K, or K in hopes that they can host it somewhere & post a link for you all to use. Having the data in excel is nice because you can sort by any column & compair the changes.

Here is a chart that I created from the data which shows how as the waist width gets wider the tip/waist difference diminishes a little, and the waist/tail difference decreases significantly. I conclude (like you all already knew) that as a ski gets wider, it needs less sidecut & more taper.

In order to have the tail represented acurately below the waist on the chart I took the waist width & subtracted the (tail-waist) value.

Unfortunately there is some data which would be tremendously helpfull, but is largely unavailable. Sidecut radius is only occasionally available and only applys to one length of the same model of ski. The running length and widest tip point to widest tail point measurement would be nice to know too. But tip/waist/tail is really all we get.

My epoxy arrived so the onlythings I still need are all the wood products & the ABS & topsheet plastics.

Linsey at Snowboard materials told me that the isosport topsheet materials is called PBT & is .024" (0.6mm) thick. I have not called any local suppliers to see if they can get it yet. I know I can get UHMWPE in .020" thickness up to 6" wide on a roll. That would be mostly clear & reasonably durable. The UHMWPE is my back-up if I can't locally source the PBT.

hose-man. write up a brief article about your thoughts and send it our way along with the Excel file. (see the format under "articles" section ). we'll be glad to post it. it's interesting information..

send to leangkk "at" yahoo dut com if you like.

Hi!

After my successful ski building process I made a small website about building skis in German, because there were a lot of people who asked me to do this.

http://www.stud.uni-karlsruhe.de/~uryo/karsten3000%20skibau%20GmbH.html

Nice.

I was wondering if you are going to make also the second ski of the pair...

its already done, but at the moment i dont have the time to integrate it into the page. maybe in two weeks, when I'm back from fuerte ventura...