[Flying Scotsman]

Anybody use one of those LASER line generator things for aligning the gear leg fairings? I have one that came in really handy for the wheel pants, and here's my thinking:

Drop a plumb bob from somewhere around the mid-point of the gear leg, measure X from airplane centerline to plumb bob, and measure height Y at that point;
Go waaaaay back by the tail and measure out from centerline X, put LASER device on a tripod, set LASER beam at height Y;
Rotate LASER beam with nifty built-in line generator rotator thingie so that line is "scribed" by LASER onto the rear of the gear leg from top to bottom (this should be the exact trailing edge of the gear leg);
Slip gear leg fairing over gear leg, align trailing edge with LASER (fairing has already been trimmed to length and hinges installed); clamp in place; install intersection fairings to hold in that position, etc.

Will that work? Anybody done this?

TIA!

Steve

 

[krwalsh]

Like this?

This is on our Cozy MK-IV, but the idea is the same. Drop two plumb bobs from the centerline of the plane so that you can align the laser. Then align the wheel pant to the laser. Once you have it right, put the laser perpendicular to level the wheel pant at cruise attitude. It takes a couple rounds to get it right, and probably would be best done with two lasers.

Our laser level is mounted to a micro-fine tripod adapter that allows you to adjust it without having to move the actual tripod. It makes getting it just right pretty easy.

Oh, and close the hangar door, you can;t see the line with it open!

 

[Flying Scotsman]

That's what we did for the wheel *pant*, I'm asking about the gear *leg* fairing (which Van's insists has to be dead-nuts on alignment-wise).

 

[[email protected]]

Mason line...

Mason line wrapped around the leading edge pulled to the tail with a parallel offset from centerline... center the trailing edge gear leg fairing between the lines. Very easy and accurate; you will probably spend lots more time setting up something with a lasar and figuring out how to center get the trailing edge in good trail.

 

[mannanj]

Laser

Make sure the laser is dead on, not only for level, but for horizontal too. I had a cheap one that I used until I found that the dot was about 1/2 in. left of centerline at about 10 ft.

 

[Flying Scotsman]

Mason line wrapped around the leading edge pulled to the tail with a parallel offset from centerline... center the trailing edge gear leg fairing between the lines. Very easy and accurate; you will probably spend lots more time setting up something with a lasar and figuring out how to center get the trailing edge in good trail.

This is Van's method, right?

Seems like more work to make some sort of device to hold the lines at the rear of the plane (the empennage is not on at this time) steady, perpendicular to the floor, perfectly straight up and down with no twists, etc.

 

[[email protected]]

Use a helper or tape them to a chair

This is Van's method, right?

Seems like more work to make some sort of device to hold the lines at the rear of the plane (the empennage is not on at this time) steady, perpendicular to the floor, perfectly straight up and down with no twists, etc.

Use a helper or a piece of tape and a chair, table, blocks, whatever.

 

[Flying Scotsman]

Make sure the laser is dead on, not only for level, but for horizontal too. I had a cheap one that I used until I found that the dot was about 1/2 in. left of centerline at about 10 ft.

Yeah...I figured that if I set it up with the line vertical, tripod centered over the mark, height of laser correct, and the line intersected the gear leg at the correct point, the laser line would have to be parallel to the fuselage. Then rotate the line until it matches the gear leg.

 

[Flying Scotsman]

Use a helper or a piece of tape and a chair, table, blocks, whatever.

And that's easier than a Bogen tripod how?

 

[vlittle]

Here's what I did (Van's reprinted this in the RVator). The door is mounted to a 2x4 attached to the tail deck. The line drawn on the door is exactly in line with the gear leg.

 

[Flying Scotsman]

Sigh......

 

[Ron Lee]

Isn't this fun?

Vern's method appears to meet accepted construction protocol since he used duct tape or equivalent.

 

[krwalsh]

Oops

That's what we did for the wheel *pant*, I'm asking about the gear *leg* fairing (which Van's insists has to be dead-nuts on alignment-wise).

Sorry, I misunderstood. What you need is one of these:
http://www.robart.com/products/model-incidence-meter

Which we replicated with a few wood v-blocks and a SmartLevel to do exactly the same task when we put our gear leg fairings on.

 

[Flying Scotsman]

Maybe I'll just take it to one of our wind tunnels.