PSA: Mount your own fucking skis.

[nb1234]

Great thread.

Another way to use a combination square to get the exact center line:

Put a strip of masking tape down middle of the ski - just eyeball it. It's gotta be long enough to span the whole length of the binding mount area - longer is fine, too. Put another strip or two down on top of that one - you'll see why later.

Take your combo square put against the ski edge with the "ruler" part going across the ski top. Yes - the ski edge is not parallel to the center line, but as you'll see in a bit, it doesn't matter.

Take an x-acto knife - place its edge against the ruled egde of the square, somewhat near the center of the ski. Use one of the ruled measurement marks as a reference. Many combo squares have those rule markings stamped into the edge, which helps you hold the blade there. Holding the tip of the blade agains the ruled edge of the combo square, and ever so slightly biting into the masking tape, pull the two together down the length of the masking tape. You're scoring a very shallow line into the tape down the length of tape - and it's only somewhat close to the actual center line. This will be a line that effectively parallel to the ski edge (an arc that matches that of the edge). This is why you use a double thickness of tape - to allow you to comfortably score the tape without marking the actual topskin.

Now flip the square over and do it from the other side - putting the xacto blade on the precisely corresponding measurement mark on the opposite side.

Unless you happen to eyeball the exact center when scoring the lines (unlikely) you'll have two lines scored into the tape. Those two scored lines exactly span actual centerline of the ski. If they're close enough, you can then split the distance to get the true center line. If they're somewhat far apart, repeat the process moving the xacto blade a bit closer to the center line. If you repeat it once or twice, you'll get two lines that pretty much tell you where the exact center line of the ski is.

With this method, you're not actually measuring anything - you're accurately bisecting ski to get the exact center line.

An even better tool than the combo-square/xact knife setup is adjustible wood scribe - but I'd suspect most of us don't have such a thing - but they're not hard to make, either.

Finally, if you don't mind somewhat sacrificing a combo square (they're cheap) - you can file a little notch into the ruler edge to exactly hold the exacto blade in the same spot when you flip it over. This works better if you want to use a pencil instead of an xacto knife.

[XXX-er]

so what you are saying is draw 45degree angles across your top sheet and where they intersect is ski middle, use the ski edge not the top sheet edge ?

[nb1234]

so what you are saying is draw 45degree angles across your top sheet and where they intersect is ski middle, use the ski edge not the top sheet edge ?

If you're replying to my post (#153) then no. The problem with drawing 45's and connecting the intersections is that when you flip the combo square to the other edge, you're not sure you're getting it exactly in the same position on the new edge as you had it on the original edge. The "crossing points" in this method could be off of the actual center line.

The method I describe (not mine but is a common technique to find the center line on a surface from two symmetrical edges) has you scribe two lines (at a minimum) down the ski onto the tape - each parallel to the one of the ski edges. The actual ski center line is the middle of the gap between those two lines. You make those two lines close enough together, you get a very precise "boundary" of where the actual center line is - more than close enough to then align your template.

[XXX-er]

If you're replying to my post (#153) then no. The problem with drawing 45's and connecting the intersections is that when you flip the combo square to the other edge, you're not sure you're getting it exactly in the same position on the new edge as you had it on the original edge. The "crossing points" in this method could be off of the actual center line.

.

I would draw a 90 degree line from both edges on masking tape & take the middle of those 2 lines if they are off by much and draw each 45 diagonal from that line

[nb1234]

Here's a sketch of what I'm talking about. Obviously, the arcs I drew for the edge radius is very exaggerated, but you should be able to get the point.

In this case the scribe lines actually intersect - so you can connect the intersection points and get the actual center line (shown in red.)

Depending how you set up your scribe, it's also possible that the two scribe lines don't intersect. If they're close enough you can simply find the middle of the "gap" between the two for the center line, or readjust the scribe and do it again so they do intersect.

[COBuckeye]

Since this thread has some good mounting info and is the most recent mounting thread that is not "where should I mount my _____", I figured it would be a good place to ask this question:

If you clamp your ski to the drill press/workbench/table this will decamber the ski. If you drill the ski in the decambered state will this cause problems? If yes, what is the best way to drill so as to not decamber the ski?

Apologies for the nerdy jong question, but I couldn't find this in any of the other mounting threads.

[wooley12]

Not enough to make a difference. I've mounted plenty.

[Jethro]

Since this thread has some good mounting info and is the most recent mounting thread that is not "where should I mount my _____", I figured it would be a good place to ask this question:

If you clamp your ski to the drill press/workbench/table this will decamber the ski. If you drill the ski in the decambered state will this cause problems? If yes, what is the best way to drill so as to not decamber the ski?

Apologies for the nerdy jong question, but I couldn't find this in any of the other mounting threads.

You will not decamber a ski clamping it flat to a table. A drill press is only about 6" wide, and you will not even notice any camber compression. You can repeatedly reverse flex skis between moguls and terrain undulations, with full body weight and skier velocity. There is no way you will decamber a ski on a workbench. Maybe you could if you left it that way all summer in a hot shed.

[jondrums]

If you clamp your ski to the drill press/workbench/table this will decamber the ski. If you drill the ski in the decambered state will this cause problems? If yes, what is the best way to drill so as to not decamber the ski?

great observation, but the answer is an unequivocal "no". If you consider the total possible error that this could introduce it is way way way less than a typical drilling location tolerance. It'll never matter. This can be proved using geometry, but that is an exercise I will leave to the reader.

[COBuckeye]

Great, thanks all for reassurance.

[Drewbrese]

Here's a sketch of what I'm talking about. Obviously, the arcs I drew for the edge radius is very exaggerated, but you should be able to get the point.

In this case the scribe lines actually intersect - so you can connect the intersection points and get the actual center line (shown in red.)

Depending how you set up your scribe, it's also possible that the two scribe lines don't intersect. If they're close enough you can simply find the middle of the "gap" between the two for the center line, or readjust the scribe and do it again so they do intersect.

Interesting method, might try that this season.

[toast2266]

Since this thread has some good mounting info and is the most recent mounting thread that is not "where should I mount my _____", I figured it would be a good place to ask this question:

If you clamp your ski to the drill press/workbench/table this will decamber the ski. If you drill the ski in the decambered state will this cause problems? If yes, what is the best way to drill so as to not decamber the ski?

Apologies for the nerdy jong question, but I couldn't find this in any of the other mounting threads.

In addition to what others have said, it's not really necessary to clamp the ski at all when using a drill press. Just make sure everything is lined up right and hold onto the ski - the little drill bit you're using won't cause it to go anywhere.

[JayPowHound]

If you're replying to my post (#153) then no. The problem with drawing 45's and connecting the intersections is that when you flip the combo square to the other edge, you're not sure you're getting it exactly in the same position on the new edge as you had it on the original edge. The "crossing points" in this method could be off of the actual center line.

The method I describe (not mine but is a common technique to find the center line on a surface from two symmetrical edges) has you scribe two lines (at a minimum) down the ski onto the tape - each parallel to the one of the ski edges. The actual ski center line is the middle of the gap between those two lines. You make those two lines close enough together, you get a very precise "boundary" of where the actual center line is - more than close enough to then align your template.

With this method you still have to start the scribe lines from the same point along the length of each edge, and use the same measurement in on the square right? Just trying to wrap my head around it.. sounds like it's worth a shot this season.

[Alpinord]

If you're replying to my post (#153) then no. The problem with drawing 45's and connecting the intersections is that when you flip the combo square to the other edge, you're not sure you're getting it exactly in the same position on the new edge as you had it on the original edge. The "crossing points" in this method could be off of the actual center line.

Just thought I'd add a slam-dunked sketch to show this potential train wreck scenario:

[alkos]

Here's a sketch of what I'm talking about. Obviously, the arcs I drew for the edge radius is very exaggerated, but you should be able to get the point.

In this case the scribe lines actually intersect - so you can connect the intersection points and get the actual center line (shown in red.)

Depending how you set up your scribe, it's also possible that the two scribe lines don't intersect. If they're close enough you can simply find the middle of the "gap" between the two for the center line, or readjust the scribe and do it again so they do intersect.

I really like this method - it's quick, accurate, and no measuring required.

The only think I'd add is that I use a pencil compass/scriber to lay down the marks on my ski. Not sure how you'd use a combo square, but this seems simpler to me.

Something like this: http://www.homedepot.ca/product/penc...scriber/922660

[wooley12]

I use folded paper at two points, tape and a long flexible ruler. But this is a drifting thread.

[bern43]

Just thought I'd add a slam-dunked sketch to show this potential train wreck scenario:

Yeah, that does look like a disaster waiting to happen. I used the .pdf centering template on a true bar with a micrometer. Then, once the template was on, I double checked it with the micrometer from the edges. Seemed to work fairly well.

[nb1234]

I really like this method - it's quick, accurate, and no measuring required.

The only think I'd add is that I use a pencil compass/scriber to lay down the marks on my ski. Not sure how you'd use a combo square, but this seems simpler to me.

Something like this: http://www.homedepot.ca/product/penc...scriber/922660

The important part of this method is that the scribing tool you use ensures a fixed distance between the guide that rides along the ski edge and the scribing point. The compass scriber in your link can change angle and that means the scribed line won't be parallel. If you want an "official" tool to do this, a traditional woodworker's marking gauge would be ideal: http://thebestthings.com/newtools/gr...king_gauge.jpg

However, it's easy to make such a thing or to file a little notch along the edge of your combo square in which the xacto/pencil can ride so it doesn't drift side to side. Very important that it doesn't drift. I just happened to suggest a combo square because many folks have such a thing around. It can also be easily made out of a couple of scraps of wood glued/screwed together - one to track to the ski edge and the other with a notch to hold the scribing tool/pencil in a fixed spot. Very low tech, but super accurate.

Also, to avoid marking up your ski tops, just lay down a strip of masking tape - it makes the scribe line easier to see anyway.

[Drewbrese]

Could you mount up a fine tip sharpie instead of the knife?

[nb1234]

Could you mount up a fine tip sharpie instead of the knife?

Sure, but the lines will intersect at very fine angles, so the finer the marker the better. A fine 0.3mm roller-tip pen or fine point mechanical pencil also works great.

[alkos]

The important part of this method is that the scribing tool you use ensures a fixed distance between the guide that rides along the ski edge and the scribing point. The compass scriber in your link can change angle and that means the scribed line won't be parallel. If you want an "official" tool to do this, a traditional woodworker's marking gauge would be ideal: http://thebestthings.com/newtools/gr...king_gauge.jpg

That's a good point - I usually eyeball that the compass is coming off the edge at 90degrees relative to the centreline of the ski. I lay down masking tape and scribe a pencil mark that is roughly half the length of the ski - this way any small inaccuracies from twisting of the compass are offset by the general contour of the line. IMO, the tolerances aren't that tight for mounting a ski binding, and this method tends to find the centreline of the ski within 1mm or so.

[Shorty_J]

Sure, but the lines will intersect at very fine angles, so the finer the marker the better. A fine 0.3mm roller-tip pen or fine point mechanical pencil also works great.

You're not wrong... but if you're worried about misplacing your mount by 1/2 the width of a fine sharpie and you think you're good enough with a drill to honour that, then good on you.

[Kim Jong-un]

I used to have a small cheap square that I drilled holes in for pen...worked ok for a while. Then I finally broke down and got one of these for $13...works great--you just need a fine point pen that fits in the holes.

http://www.amazon.com/INCRA-TINYT03-...ref=pd_cp_hi_2

[Alpinord]

I used to have a small cheap square that I drilled holes in for pen...worked ok for a while. Then I finally broke down and got one of these for $13...works great--you just need a fine point pen that fits in the holes.

http://www.amazon.com/INCRA-TINYT03-...ref=pd_cp_hi_2

Those are nice to have for a lot of things. A mechanical pencil works with them and sanding the point of any pencil also works fine.

Similar to scribing to an intersection, it's quick and accurate to use the end of combination square to simply scribe a series of near-center dashes from both edges beyond both ends of the mounting area, split the difference and use a long straight edge to draw the center line:

Then double check that you get the same measurement from each edge along the center line.

[~mikey b]

that's how I've been doing it