Ski Builders Forum

I guarantee that a 2-12-2 poplar maple core at those widths and 22oz triax will be comparable to some of the stiffest skis on the market. I did exactly that with digital calipers and I used a liner taper with no flat spot and Supersap resin. 2 pair.
YMMV.
MM

I'm not shooting for super stiff, just stiff. I think I'll got will 2-11-2 with a flat mount of 350mm and see what happens.

I'm using the excel work sheet for ski dimensions to pick specific points along the length of the core to measure width and transfer that yo my profiler spacer blocks.

Now that I've nailed down the core simms some I can cut my mdf this weekend.

I picked up a digital caliper from the local NAPA store today and some grip tape. I've got enough t nuts to make 20 points on my profiler to hold spacers.

Now if I can just get my heaters figured out I will be set. The heaters get warm but not hot. Not sure they are any good. I will have to get my electrician to look at them.

Thanks so much for the help. This is all very useful info

I've been shooting for 2-11.75-2 with no flat spot.
The last cores I made were 2.2- 12- 2.2 (That last 1/4mm is hard with the router, but all three cores came out the same! 2.21-12-2.22mm to be closer to exact)
I put a couple cardboard spacers near the ends of my profile rails to make the taper more gradual.
They are 19oz triax and 3) 24k carbon tow below the core.
They are quite stiff but not as still as XXLs. (waiting patiently for base and snow)
Although the walnut pair hasn't delam-ed yet despite lots of flexing.
I might try to ski on them (with a backup pair in the car to be safe)

The pair last year 2.1-12.2-2.1 turned out to be the stiffest skis I've skied since the 80s (Stiffer than XXLs) but they ended up curing without a press and were 6+lbs each. 22oz triax ,a thick (.0125") 24"long aluminum binding plate and a triangle of 22oz triax in front and behind the binding to the tip and tail. solid, damp, heavy!
Still... a super fun, full speed ahead, ski you have to drive or it'll drive you!

I like stiffer skis but sometimes a softer ski that you don't have to drive all the time would be nice!

Have yet to do the flat spot in the binding area.
Not too sure why I'd want to?
So far the rounded taper from center to end has a great round flex I like.

sam

I guess I'm going with a flat spot just because I thought it would make mounting the binding easier.

if 11mm ish is close to a legend PRO or XXL then I think I'd be happy with something just lightly less stiff. So again I think I'n now in the ball park. Thanks

The flat spot is neither here nor there for binding mounting. And unless you have zero camber then the flat spot doesn't actually end up "flat" once the camber is pressed in. Usually with a round taper (no flat spot) the radius of the core shape is so big that it's not that far off flat anyway
The main thing a flat spot does is affect the flex. The wood wants the bend at the junction of taper and flat so a flat area creates a very stiff flex under foot with flex moved out into tip and tail rather than the rounded flex you get from a non flat spotted core.

Falls beat me to it...
If you machine your core 11mm with a flat spot then taper to 2mm your skis will be stiffer than if your taper starts in the middle of your ski.
How much stiffer will depend on the length of your flat.

sam

right on. That is the kind of stuff I needed to know. After hearing that I changed and went with a 2-11-2 profile without the flat spot. I like a round flexing ski and fro the sounds of it the flat spot I designed would just make a super still ski that would be tough to decamber in a turn.

I'm hopefully going to start work on the core profiler today. I used the skidimms excel chart to create my profile and then divided the running length of the ski by 16. This gave me 16 a 96.5mm interval between points that I need to measure. I matches those points with the skidimms excel chart to figure out the desired core width at each point. then I added 2 cm on to everything and this will be my spacer height.

I'll cut my spacers on my band saw. I'll drill and counter sink the t-nuts and hex cap screws 5/16. The spaces also get drilled out. And there will be grip tape on the tops surface.

right on. That is the kind of stuff I needed to know. After hearing that I changed and went with a 2-11-2 profile without the flat spot. I like a round flexing ski and fro the sounds of it the flat spot I designed would just make a super still ski that would be tough to decamber in a turn.

I'm hopefully going to start work on the core profiler today. I used the skidimms excel chart to create my profile and then divided the running length of the ski by 16. This gave me 16 a 96.5mm interval between points that I need to measure. I matches those points with the skidimms excel chart to figure out the desired core width at each point. then I added 2 cm on to everything and this will be my spacer height.

I'll cut my spacers on my band saw. I'll drill and counter sink the t-nuts and hex cap screws 5/16. The spaces also get drilled out. And there will be grip tape on the tops surface.

well strangely enough the skis we made at 2-11-2 were to soft but that was beech/poplar. Thats why I am switching to a flat spot. I want the flex point closer to the tip but still need it stiff underfoot.
1 mil will kill ya.

I got about 1/2 way though cutting my spacers today and realized I was cutting them wrong. Instead to taking a base height of say 3 cm and subtracting the core width from each spacer to get a negative profile. I added the width on to each spacer giving me a great profile of the core but not a negative profile. duh.

So anyway I now have it straightened out and I'll cut them correctly tomorrow. Luckily I did not waste too much material and I might actually be able to use a few of them.

I'm measuring with my sweet digital calipers. I tried cutting on my table saw and I was able to come pretty close but not accurate enough. If the fricken laser beam on my new table saw would work it would be better. I have to call sears for a replacement part as it is still under warranty. I'll try cutting with the band saw tomorrow instead.

Why not use your planer to make your spacers?
I use left over strips of maple. (from sidewalls etc.)
Run them thru the planer, until they're the thickness I'm after, then cut them to length.
Then I mark the thickness on them with a sharpie so the next time I need a 10.2mm shim (for example) I just grab it out of my box of shims.

sam

That is a good idea. Right now I'm using MDF for my spacers just because that is what I have. I got a sheet of MDF free from a guy on craigslist.

I guess I could cut a 3 cm strip and then plane that down in the appropriate intervals for each spacer. It will be dusty but it will be more accurate.

Thanks for the tip.

Left over base material is another option.

sammer the planer method is the way to go for sure. Thanks for reminding me of that. I now have the spacers done and the MDF planed flat. I had to plane the MDF because it had gotten some water spots on it and was a little bumpy. I was able to sue all of my spacers from yesterday's screw up with the exception of the biggest ones.

Unfortunately I did not get as far on my profiler as I would have liked. my firewood was delivered today and my wife needed me to do some stuff for her. And we all know the honeydo list trumps ski building most or all of the time.

The core profiler is almost done now. I just ran out of battery in the drill or I would have it finished. To make straight drill holes without a press I used a drill guide. Basically a jig that your regular drill attaches to, sweet little tool. Without that I would have never gotten all the holes to line up right.

To get the top countersink holes right I had to improvise. Since I'm using a 5/16 inch hex head cap screw and 5/16 inch washer I had to use a 3/4 inch hole for the countersink. The only 3/4 inch bit I had was a speed bore. So inserted a screw with washer into the pilot hole and traced the washer footprint. Then I used the mark 1 eyeball and my drill guide to put the 3/4 speed bore bit on target. I have about 1/2 the countersunk holes done and they all look like the line up nicely with he T-nuts.

I'm just 4 t-nuts, screws and washers short though since I added 2 more spacers on the ends..

All in all pretty successful today. Hopefully I'll be able to put a mock core together this week and give her a try.