Hot Box Prep Question

[Sinecure]

OK. So I'm going to take some boards to spend a night in a hot box. My question is what prep should I do beforehand.

- Do I need to hot scrape them a few times?

- What wax should I use for hot scraping? Just a basic storage wax, or my normal riding wax (Holmenkol Alpha Mix)?

- Do I want any wax on the base when I drop the boards off or should I ride the boards a few runs to get the wax off (or brush them with a brass brush).

- Do I need to specify what wax the shop should use when the hot box it?

- My boards' bases vary in terms of condition/structure. Do I need to / want to get base grinds on all the so-so ones before hand, or can I just wait and do it when they really need it?

TIA for the help.

[Guest vlad westervaeld]

First: be CAREFUL about heating your base.

Your polyethylene base is sintered, that is, it's comprised of tiny, dust-like particles of polyethylene which are

c o m p r e s s e d

to form a semi-solid p-tex base....overheating this base will melt the sintered particles together, and create a homespun version of the cheaper , solid "extruded" base, which is far, far slower than your factory sintered base.

further, 'hot boxes' heat more than simply the base- they heat the laminates of the board and promote torque displacement, whereby your sled will take on a slight twist over it's length, which will make it run for sh*t.

You now have something useless for 'boarding, and even the neighborhood groms will turn up their noses in disdain when you offer this bowtie-pasta abomination to them for their backhill sledding.

always treat your p-tex as you would human skin.

now, then:

p-tex is always faster than wax.

over-waxing is far and away worse/slower than underwaxing.

scrape like a mofo, scotch-brite, BRUSH (to open up the base structure) and then brush some more.

PRINCIPLE MOST OVERLOOKED by the recreational racer/carver:

base structure/rilling.

a flat, very smooth base, running down the course, creates friction via suction, much the same as a wet hand, when pressed along a window, 'grabs'.

to break up this 'grab', you need base 'structure'. this is the pattern of tiny grooves and lines along the base which the grinder leaves... it breaks the suction up.

very

very

very

important concept.

the corrollary to structure?

"Rilling", the practice by which one creates a pattern of tiny grooves along the base to effect 'shedding' of water form beneath the sled.

no matter how cold the course, your base is running on a surface of water.

in order to reduce 'suction drag', you gotta provide channels for the water to follow to exit the base X surface vector.

now, then- the shorter the distance, the faster the water exits, and the greater the volume of water is shed from beneath the running surface, and the faster the board (and clock-stomping rider) move ahead.

so, it follows that straight-line rilling along the base, from shovel to heel, makes the water travel a longer, more self-accumulating distance, so....

you wnat to rill in either an S pattern along the entire length of the base, fore/aft, or cross-hatch your rilling.

I typically opt for a cross-hatch on my single-event sleds (SG, DH) and s-pattern on my dual-event sleds (SL, GS).... that's just my own bizarre li'l mojo preference.

once you've achived sufficient rilling (with a brass rilling tool, etc.) go ahead and wax the warm (90-110 o f) base lightly, scrapoe well, and then brush like a lunatic until your rilling and/or structure is all clear.

you will kick ass.

[Sinecure]

Thanks for that re-post Vlad. I read the same post in another thread (I did use the search feature before posting).

Assuming I'm going to go ahead and hot-box my boards, anyone have suggestions or ideas on my original questions?

[Guest vlad westervaeld]

just lookin to help out. being you have all those questions going into it, i thought that reconsideration of even submitting to the process might be in order.

every answer, in this life, brings even more questions.

[D-Sub]

OK. So I'm going to take some boards to spend a night in a hot box. My question is what prep should I do beforehand.

- Do I need to hot scrape them a few times?

- What wax should I use for hot scraping? Just a basic storage wax, or my normal riding wax (Holmenkol Alpha Mix)?

- Do I want any wax on the base when I drop the boards off or should I ride the boards a few runs to get the wax off (or brush them with a brass brush).

- Do I need to specify what wax the shop should use when the hot box it?

- My boards' bases vary in terms of condition/structure. Do I need to / want to get base grinds on all the so-so ones before hand, or can I just wait and do it when they really need it?

TIA for the help.

my only point on this would be:

if youre trusting the shop to do this, you should ask them these questions, and they should have solid answers

if not, I wouldnt trust them with the boards

personally think hotboxing is just overkill.

[philfell]

Hotboxing if done correctly wont twist your board. But like D-sub said it is overkill. Most elite racers will hotbox their board or skies after they prep them after a grind. Unless you really care about a tenth or so per run you should just hot scrape with a base prep wax then wax as normal. You'll get way more out of your board by getting the wax temp right than you will by hotboxing.

[Guest vlad westervaeld]

actually, the worldcup athletes whom use hotboxing are still in the minority. it can (again, as pointed out by previous posters, when done incorrectly) twist boards whose laminates are constructed of meterails with unlike thermal loss coefficients, such as, say, kevlar and titanium, in sandwich. it also plays havoc on the adhesives and topsheets and will kill the temper of the edges and create w more lifeless board.

that extra tenth which phil mentions might be won elsewhere, through other tuning practices.

[D-Sub]

if its potentially risky like that, why is it even done at all?

[Guest vlad westervaeld]

everything revolutionary and good started out risky.

i am confident that a really slow, lower temp, more consistent form of hotboxing

will develop from the tech we have now. i don't use 'em, i don't recommend them, so i'm probably not the guy to ask why people use them.

luckily, i had a copy of my original post to this thread saved, as i reposted it elsewhere.

my original got deleted, but i had backup:biggthump

[Sinecure]

actually, the worldcup athletes whom use hotboxing are still in the minority. it can (again, as pointed out by previous posters, when done incorrectly) twist boards whose laminates are constructed of meterails with unlike thermal loss coefficients, such as, say, kevlar and titanium, in sandwich. it also plays havoc on the adhesives and topsheets and will kill the temper of the edges and create w more lifeless board.

that extra tenth which phil mentions might be won elsewhere, through other tuning practices.

Kill the temper of the steel edges? Hot boxes run at like 60C. You iron at like 120-130C? Are you telling me that you can change the temper of steel at a temperature that is half what I iron at?

As for your other points, even Toko does concede some of that:

Rarely, older skis can be damaged by the Thermo Bag at temperatures, especially when treated for too long or at too high temperatures. This is often because the resin and glues in the skis are no longer consistent and the ski reacts differently to the heat in one part of the ski compared to another. This can result in warping or collapsing of the base. However rare, this needs to be considered before treatment in a Thermo Bag.

.

Oh, and that site basically answered my questions. Here's the info:

The Toko Thermo Bag is a hot box that works like none other. It is portable (after 3 minutes of packing up, fully digital, and very effective. The ventilator ensures consistent temperatures throughout (as compared to homemade hot boxes) greatly reducing the chance of damaging skis. The temperature controls are digital - simply dial in the desired temperature. The Toko Thermo Bag also offers digital temperature readouts - desired temperature and actual temperature (which become the same after a short while). Many World Cup teams own a Thermo Bag as well as many of the world's best ski racers have their own. The Thermo Bag fits 12 pair of Nordic or 4 pair of Alpine skis (depends some on design of ski).

The Thermo Bag is used for two purposes. First, to get wax into new or freshly stone ground bases. A soft wax such as System 3 or World Loppet Yellow should be ironed on the ski prior to treatment. Putting the skis in the bag for 6-8 hours at 62C is appropriate for such a task. After treatment, it is important to iron in a wax such as System 3 or World Loppet Blue to harden the base up. Otherwise the base will be so soft, it will oxidize and scratch easily. It is also a good idea to check the skis after 4 hours of treatment to make sure that there is enough wax left. If not, they should be taken out, more wax should be dripped on, and they should go back in the bag for more treatment. An important point regarding wax penetration is that generally a soft wax will go deeper into the base and at a higher percentage. Once that soft wax makes it in, it is easier for a harder wax to get there too. Without the soft wax treatment, the bases would never reach such a high degree of wax penetration/saturation.

The second purpose is for race preparation of skis, especially in colder temperatures. Dibloc HF Blue can be ironed into the ski in the morning, the skis can sit in the Thermo Bag for 4 hours, then the Thermo Bag can be unplugged so the bag (and skis) cool very slowly overnight. In the morning, the skis need to be scraped and brushed out. This treatment will yield a superb race day finish. The most superficial layers of base will have a very high percentage of wax in them as the heat treatment coupled with the extremely slow cooling process will yield this. This slow cooling is the opposite of waxing the skis and throwing them outside in the cold weather which pushes the wax out of the base.