Forward Fuselage (Continued 5th installment.)

December was a busy month.  No real time applied to building.

Started the new year test fitting the firewall to the front of the airplane.  Clamped the whole assembly together with "C" clamps and aligned it to the center line I struck on the floor a few months ago.

I  marked the center line and the Horizontal Reference Line (HRL) on the firewall and the forward bulk heads.

I found plumbing the center line to the mark on the floor was easy.  Trying to find the HRL was starting to be difficult.  How do you find a line that is out in the middle of no where?

I tried stretching a taught string,  but there is no place to tie it off.  So, I was in a dilemma on how to locate the HRL, consistently, during the assembly of the fuselage.

I have one of those lasers used to hang pictures and stuff on the walls of the house.  It shoots a line around the room.  It can hit 2 or 3 walls.

I set it up on a camera tripod to try out.  It proved to be too dim to see and was very inaccurate.  I could not get any repeatability from the laser.

I priced out getting a cheap tripod with spinning laser.  Nothing under a few hundred dollars.

I found that the digital level I bought has a laser.  I mounted it to the camera tripod and with several attempts at leveling the laser in two planes I found if I was careful I could find the HRL with some accuracy.

The attached picture shows the  red laser going through the hole for the HRL in Station 99.35 and shining on the HRL line I drew on Station 73.75.

Looking pretty good to me.  When I swivel the tripod, the laser follows the HRL around the structure.

I will try this for a while and try and build my trust with it.  Before I get to much further along I will check the CS for being level in the fixture again.  Just to make sure it hasn't moved prior to moving on in the assembly of the fuselage.

Later,
BWW