Ski Builders Forum

Hello!

I have just finished the first ski of my second pair!
Thanx to all the tips I ve read on this forum, it looks far far better than the first ones!

But there are (at least :-) ) two remaining problems

1) I 've made the same kind of mold as in the "how to" section. To cover the gaps between the ribs, I used two layers of 3mm mdf boards. However, the base of the ski still looks wavy... Any idea?

2) When trimming, at the end, the excess of material, I have to use an incredible amount of jig saw blades because they get spoiled by the edges. Yet, the main, pb is, that the topsheet has a tendency to get un stuck by the movements of the jig saw blade. Any idea?

cheers!

1) eew, no good idea at all. fill up the gaps? add more mdf? but i`m really not that convinced of any of those ideas. but probabely the best would be to fill up the gaps

2) there was a discussion on jigsaw blades somewhere in this forum. but i couldn`t find it myself either. anyway, the conclusion was: use some lubricant and saw blades for metal. there are two kind of sawblades for methal: there are some with a wavy blade and very small teeth and there are some with a straight blade and big teeth. take the ones with big teeth!

1) Are you using a vacuumed press? If so, is it possible to take out too much air pressure out of your bag? Making the 3mm MDF bend in-between the ribs? Would this also suck out too much epoxy from your top later?
OK so those are just more questions for you but that is were I would start looking. Wish I could give you some real answers.

I use a jigsaw blade for cutting tiles. Its a straight blade with small bits af abrasive on the side. It works well.
similar to this one

i agree with yoki, this blades can cut very well titanium i saw it in a skifactory i visited

All of my molds have MDF ribs, but I've gone from covering the gaps with thin masonite to using one piece of MDF. The MDF essentially covers the bottom part of the mold (part that is the running length of the ski). The tip/tail sections of the mold are separate and do not have gaps. Here are some photos to illustrate:

1. The mold showing the piece of MDF covering on the bottom and then butting up against the tip mold.


2. A close up of the tip mold, which is made from sandwiching lots of MDF pieces together to form a sold tip mold. Notice how the MDF that covers the gaps of the ribs (on the bottom) meet the tip mold.


3. Shaping a 1/16" sheet of aluminum over the mold. Underneath the aluminum will be a thin silicon heater.


4. I painted the mold black, then fitted the heater (red-orange color).


5. Finished mold.


As for jig saw blades, I usually spend a few extra dollars to buy blades that are designed to last longer. I avoid low-cost blades because in the long run it's more expensive. The blades I use are designed to cut thick hardwoods. I don't have the exact make or model of the blades on hand, but I'll try to dig it up. I can't remember if they were made by Bosch. Anyway, I've been able to use about 1.5 blade per pair of skis. Before that I was going through about 3-4 blades per ski. Cooling the blades is very important. I've even tried periodically dipping the hot blades into ice water to cool them down. It helps, but some form of continuous flowing lubricant will work better. A nice band saw helps too, but again you need to get a good blade for it. The metal and heat can be a problem.

ive heard the word "bi-metal blade" thrown around alot.

I THINK that's what I got last time, after wasting 2 blades and not finishing one rail. It worked well for about 2/3 of the board, and is still in good condition.

The drywall/tile blade works good, but requires more precision, it will eat into the edges easier, and will also make a more wavy cut.

You want a blade that cuts awesome, lasts long, AND does not tear apart your edge. With a good blade you can cut right onto the edge without causing much edge deterioration, that means you'll have less work on the grinder later = much cleaner sidewall/edge.

Also if your blade wears out, the heat will burn your materials.

I say your best bet is the same way burton does it, use the bandsaw to cut the straight parts, and cut the curves of the tips with a good jigsaw.

do they make carbide tipped sawblades?

I use the bosch T118b blades. They work good and one blade cuts a ski and a half. Or more iif you are patient.
ra

usualy try to not touch the edges, so so you waist alot of blades, give a nice acurate cut near the edges and then finish triming the rest with a 40-60 gr tape

taking down ptex sidewalls truly sucks with a grinder/sander, that's why i run the saw right along the edge.


what you CAN do is cut as close to edge as possible without hitting it.

then clean it up QUICKLY on a grinder, like 2 passes. then flatten the base, then router your sidewall.

the routering of the sidewall will come out wavy and shit but then you'll only have a thin amount of sldewall to clean up on the grinder.

so you can go to the grinder, or even an edger, and clean the sidewall up and get it flush with the edge, without killing the edge. and then back to the router, should end up perfect. i would do it this way at the factory when given time.

A quick and easey way to clean up the excess along the edge is to use a rasp (spell). After the initial trim of the flash, take a rasp to the edge and it will clean up any high spots.
rockaukum

how bout a hand planer? that could probably shave any high spots without cutting edge stuff.