Ski Builders Forum

Hey guys, I had to jump off the wagon last season. I took a job and relocated from New Mexico to Oregon last year and the my shop time took a hit...

Back at it finally
This season I decided to see what all the heated press rage was all about.
I built some heat mats using some 22oz 90x+/-45 fiberglass that was shipped to me in error. I reallllllly cheaped out and used hardware store silicon (as in the stuff that comes in a tube). The end result vastly exceeded my expectations and my shop only smelled like vinegar for like 2 months afterwards. The mats are ~800 watts rms a piece.

I used these screw terminals that I think chrismp used? I know I got the idea from someone here.


I used drywall tape to secure the wires which worked out really well.


Maybe not the prettiest things, but they are burly and effective


The temp controller is constructed out of things I had pack-ratted away over the years... There are two temp sensors and a single SSR being read/controlled by an arduino. One of the two outlets is connected directly to the SSR. The other outlet has the dimmer switch connected in line with the output of the SSR. This enables me to "dim" the blanket that gets hotter. The setup worked great.









I tried poured polyurethane sidewalls on this set. I used the sharkthane 70-2 that fiberlay carries. This was... interesting. It's hard to imagine two liquids being mixed together and turning into a raging hot blob of solid plastic in 90 seconds. I tried to pour too much on my first shot and wasted a lot. I need to look over my notes, but I think 200cc's of total liquid ended up being a manageable amount. I wish I had take some pictures pre-pour. The channel was routed at 4 different depths to try and conserve plastic.





I had to chop my press beams down a bit to get them in my shipping container, but they still worked fine. My arduino code is super crude so I need the laptop to monitor temp.
My cassette/blanket protection was:
22 gauge galvanized -> blanket -> 0.0508 Al -> ski -> 0.0508 Al -> blanket -> 22 gauge galvanized


Skis are 183cm ~140/100/130. This set is going to by my everyday PNW conditions ride. cell phone pics... lame






I also updated my deathtrap don't try this at home might loose fingers "base grinder". The drill press head worked great.


The binding inserts were a little stressful, but ended up working out great. Can't wait to get these up on the mountain, it just needs to get colder and stop raining....


Hope you guys are doing good!

Looks good mate!
That urethane seems to be working well for you, no bubbles that I can see.

The urethane worked out great. I probably should have done some research; didn't know bubbles were an issue. The liquid had a pretty low viscosity.



Sidewall close-up. There are some realllly small pores here and there, but nothing of concern.

I like the simplicity of your base grinder!

Nice stuff there

Thanks guys!
The "grinder" does work but it's pretty slow going.
I'm using 120 grit for the most part. I have some 80 grit, but it's just too aggressive. Maybe I'll track down some 100 grit for the next set.

I have some plans to build a bigger version out of a six inch pvc pipe that will involve some jet sprayers, but my shop space is a little too constrained at the moment for another floor standing machine. One day though!

I've got two more sets planned for this season, a dedicated light weight touring ski and a park oriented ski. I'm only good for laughs in the park, but I've got some buddy requests that I'm going to try and fulfill...

Well I took these out for a abusive trip to Utah and the topsheets started to peel off...
I think I may have put the wrong side down.

Does anyone know how to determine the bonding side of the skilab nylon topsheet?. It's really not obvious, both sides are textured.

Besides the topsheet issues the skis are wonderful!

So I'm thinking of either flipping the topsheet around and trying to repress it on, or just cleaning the skis up and varnishing them. There's a sticky film left after peeling the topsheet back. No idea whats going on there. I can scrape it off.

Any thoughts?

The sticky layer might be the protective layer that should be on the outside of your top sheet?. (gets peeled off once the ski is all finished)
Just a thought...
How glossy is the inside of the topsheet once it's peeled?


sam

Great work man - I missed all the entries you made in Nov.
You might want to replace the topsheet with a clear urethane. Something relatively thick and self leveling.
You mentioned that t-nuts were a bit of a stress. If you want sight of a simple set up for ideas, then shoot me an e-mail and I will send you a few photo's.

If all other layers bonded well, it sounds like you laid it up on the wrong side and pressed the protective foil. These foils are usually slightly textured as well. I always peel a small corner of the foil just to be sure which one is the right side.

Oh dear... Don't I feel a little stupid

I went and checked the roll of material and sure enough there is a film on one side... Sammer, yes the inside is nice and smooth. Haha.
I know almost nothing about sublimating graphics and just assumed that both sides are textured because they are both meant to bonded.

Hmmmm... well I guess I have a super light-weight topsheet. The protective film bonded exceptionally well. I think I might just get all the adhesive off and then varnish the tops.
At least now I know why my topsheets are pulling up... They actually held up amazingly well considering that they're not bonded at all.

I may actually reuse the material for another set. Are there any secrets to working with nylon that's been well exposed to the elements? Do I need to flame treat it or such?

ha good one. At least it is an obvious error and an easy fix.

You're definitely not the first person to do this. Think of it this way, you will NEVER make that mistake again.

Whenever I've used clear topsheets that have a protective layer, I first determine which side is the top, and then I write the word "top" on it with a sharpie. That way you'll never put the wrong side down.

!
nice one. such a shame, but sounds like they ride well anyway.