Ski Builders Forum

whether the warrior Khans ever skied is beyond me, but nevertheless, meet Kublai, a new addition to our collection:



of course it was inspired by the works of Head Monkey, hydrant71, and others within this community...

cattrack and heat come standard.
and what color you ask? well, that's a surprise....

wow, what a monster!!!!

...nice, indeed... I like the name of this beast...

What are the material sizes on this beast, I-Beams/Channel/etc? Is it also strictly bolted together, or is there some welding done also? Great job, and I look forward to seeing the progression. --Geoff

Your mold doesn't appear to be stiff enough, but it has nice camber - when its not screaming 'let me out!!'

wow, what a beast. have you done load calcs to determine the need for
a center member for beam flex!!!!!! hee hee . massive. big pieces
of steel kick ass. i agree that the mold may need a little work, may need
provisions for RL adjustments unless you plan on only one running length.
nice work.

jason

You guys need a welder! the bolts are the weak points now, looks good tho

before i started the design i did some basic calculations assuming simply supported boundary conditions. i don't recall any red flags, but i'll double check with Solidworks/Cosmos or ANSYS FEA before i push on the gas...

there are two bottom beams (12x26 I-beams) and two top beams (10x26). the bottom beams are 95" long and the top are 105" long. vertical supports and cross members are cut from 2x6, 0.25" to 0.5" thick channel, with the exception of the two lower inside cross members which are made from 2x4, 0.375" thick channel. i purchased the steel from a metal yard and there's a nice thin layer of rust from being exposed to the elements. i cleaned the rust off one beam (top beam shown in the photo), but it cost me a brand new harbor freight hand-grinder ($17.99 + tax) -- the bearings disintegrated with no warning. now i own a dewalt grinder valued over four times the HF, which should last to clean the remaining three beams and the channels. the frame is temporarily bolted together. i don't know how to weld, but i plan to have it welded before it's painted. i'm taking advantage of the fact that it's assembled to build the bottom and top mold, cattrack, test the bladder, etc., before i dissemble it to paint. oh, i have the parts for the base and casters -- inching it around the garage gets old as i'm not much of a leaf cutter...

overall dimensions: width: 22"; height: 51.12"; max length: 105"
cavity dimensions: width: 18"; height: 13"; length: 95" (lower beams)

current weight (just beams and channel): ~1000 lbs.
with the molds, bladder, etc., it'll probably be around 1200 lbs.

i went with the open-throat design because i wanted room for the bladder to freely extend.

if Kublai fails as a press, one friend suggested: bunk bed

With the amount of $ you must have spent on building that you prolly could buy this. but dont get any ideas, i want to buy it... just have to sell the asphalt business first. lol

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... &rd=1&rd=1

big kam,

obviously your beams are plenty strong. extra insurance could come from
welding but if grade 8 bolts were used i believe it will be plenty strong. shear strength of a 5/8" to 3/4" grade 8 bolt is pretty high. just look at the
high capacity 50 ton shop presses available
http://www.grizzly.com/products/H6233 . these are bolted
with only eight fasteners for a much higher capacity that we will never need. weld some beads if you are in doubt but i think it will hold together just fine how it is. looking forward to seeing the finished product.

jason

This is my first post after browsing this site for awhile. First up Well
done Kam, Kam and Kelvin for creating such a brilliant informative website. Because of this site i have gone from knowing nothing about
ski construction to an understanding of the process.

Anyway great press, i dont think you are going to have problems with that thing falling apart, its a beast. If you dont mind me asking how much was the cost of all that I-Beam? I only ask because eventually i hope to build a press similar to yours (not as big though!!) and was wondering on cost. Thanks for your help.

I'm a little bit surprised by the weight. Not so long ago I designed a press like that but I came up to something like 6-700 kg without mold and so on.

Would it be possible to make some little drawings from the press because I don't completely understand the way you've built the vertical parts.

Geoff

Jason: i think you're right, but i'll consider the insurance. boy, i like some of Grizzly's stuff. i have one their cabinet-style table saws -- green beast.

heliski989: that press is nice...better get it. i'm feelin' a tingle in my fingers as they type this...

Tassie Boy: all the steel cost a little over $350US. i purhased enough 0.75" square aluminum tubing (0.122" thick) to make a small suspension bridge across the street to my neighbor's house; there will be some left over to make the cattrack ($200 for aluminum). bolts and nuts are expensive so i won't admit that part. not sure if the steel was a good price, but it's water under the bridge at this point b/c Kublai makes me sleep good at night. but when it's all said and done, i'll have invested $1500 - 2000 US (including heated blanket).

Geoff: i might have underestimated the weight. maybe another 100 lbs for the steel? the cattrack will weigh about 50 lbs. funny thing: i originally chose 0.75" square steel tubing (0.122" wall thickness) and placed an order with a local metal supplier, including cuts. then i thought: gee, how much will that cattrack weigh? using my 4-function calculator, i punched a few numbers and wow -- 170 lbs! i reconsidered, punched some more numbers and went with AL. i dialed the supplier an hour later before the cuts were made...phew!

i plan to write an article about the press design, including CAD drawings, etc. it'll take some time, but i'll try to keep everyone up to date via this thread...

Thanks Kam for telling me that.
I'm not sure if that is a good price or not either.
Again nice press and i cant wait to see it progress!

How is the press coming along, Kam?

here's an update:

one mold is done -- roughly 10 - 16 mm of camber, depending on length of ski.

finished the cattrack; wow, it took a long time to drill and clean the holes.


fire hoses are done (two of them, each 9 ft. long); used Head Monkey's parts list for air valves. tested the hoses at 30 psi. oh, the hose came from rockaukum (thanks!, and this is one of the reasons why we created this forum!!!)

i'll perform a dry-run test in the next few days.

profiled cores today for a new ski. bases are cut and edges attached. i plan to test Kublai by pressing a pair of skis in the next few days -- no heat cure; i'm in the process of gathering parts for the heater...