Jig and Tools Construction

Last updated on 04/22/06

After making the big decision to build an airplane the next step waiting, is hard. While waiting for the delivery of the kit I occupied my time with reading the manuals and building the jigs, setting up the work area as I thought would be necessary. The start of the wing jig frame is shown here. wing frame.jpg (46209 bytes)
I put a lag screw into the bottom of each leg of the wing frame legs to allow the jig to be leveled. After leveling each of  the legs of the wing jig are bonded to the floor using body putty. Wing Jig Leg.jpg (34053 bytes)
Using patterns from the manual, frames were cut to contour the lower surface of the wing. Some of these are placed in position but can slide up and down when the wing is placed in the jig. This allow for the wing to be leveled. form e.jpg (37782 bytes)
When the wing is place into the jig, each of the forms is adjusted up and down as well as level until the wing is fully supported level and free from twist. form_adjuster.jpg (36176 bytes)
Multiple points on the wing were used to ensure that the wing was level as well as untwisted. water_level.jpg (29977 bytes)
A flat table was made for the construction of the stabilizer and elevators. Flat table.jpg (42977 bytes)
A large cutting table was made. As most of the cutting of the Fiberglas is on a 45 degree angle or bias I made a section that was replaceable. So after years of cutting in the same spot a new piece can be put in. Cutting table.jpg (43867 bytes)
After the jigs were made, the thought crossed my mind that I still don't have the kit and the work area is full, is this going to be possible?  full work area.jpg (49691 bytes)
OK, what in the would is this? Well after cutting out the nose landing gear opening in the fuselage I tested the removed piece to see just how strong it was. Here it is with 60 pounds applied at a 10 inch moment. The test sample is 6.5 inches wide. Nosegear_cutout_setup.jpg (32474 bytes)
This is just before failure. Applied is 210 pounds, for a bending load of 2100 in/lbs. This is about 320 in/lbs. per inch of seam. Nosegear_full_load.jpg (37624 bytes)
Here it is after the failure. Look mom no toes, just a mess. Nosegear_failure.jpg (34735 bytes)
This little fixture made setting the stabilizer into position easier than the technique recommend by the manual . By threading the bolt in or out of a nut within the wood block the stab can be correctly positioned. This is still a time consuming task, but this fixture made it much easier. StabTool.jpg (64100 bytes)
I tried all kinds of cutting table surfaces. Particle board, linoleum, Formica but the best by far is polyethylene or HDPE. About $30 at the local plastic dealer for a 1/8 thick 4' by 8' sheet. Don't mess around, this is the stuff to get! And it lasts, cut after cut. CuttingMat.jpg (70845 bytes)
I made two wing jacks from old pipe stands. I add a trust bearing to allow the airplane to be lifted with very little effort.  Jack.jpg (138074 bytes)
Why are most Glasairs painted white? What if I don’t what a white airplane, what is going to happen?  Ok, there are some Glasair that are not painted white. But there is a very good reason that most are painted white, heat is the enemy of vinyl ester resin. High temperatures will soften and damage the airframe. I set out to find what the temperature difference of varies colors would be. I located a piece of old wing skin, no I didn’t screw up that bad that I had a spare wing lying around. The cutouts of the seat pan area seamed like an excellent source of simulated wing skin. I cut 6 pieces 4.5 inches square from the old seat pan cutouts and painted them different colors. I choose a range of colors to include standard white as well as yellow, red, blue, green, and black.  ColorPanel.jpg (144502 bytes)
After painting and preparing each of the sample wing skins a thermocouple was attached to the center on the back on each of the test coupons. This would measure the temperature of the shin as seen inside the structure. All six coupons where then mounted on a piece of cardboard this would act as an insulator from the ground. As all the sample where mounted to the cardboard all would be  exposed to the sunlight at the same time and in the same manor during the test. The complete test setup was then exposed to direct sunlight. The shadow shown next to the sample panels in the photo, moves away from the panel as the day passes.  Data was collected at 15-minute intervals using a Fluke data logger with an accuracy of +/1 degree. In addition to the six-temperature measurement the ambient temperature was also record. TempMeter.jpg (97468 bytes)

Observations:

bulletAs quickly as I was able to set the panel on the ground and start the data acquisition system there was a notable change in the temperature.
bulletWhite is the coolest color and Black is the hottest
bulletThe surface temperature can be much hottest than the ambient air temperature. It is more a function of infrared radiation than air temperature.
bulletYellow would be a great color for the airplane.
I build a jig to hold the fuselage during painting out of square steel tube. Its not pretty, but it works. The fuselage can rotate about it's centerline about +/- 20 degrees.
These photos are not very good at showing how this is put together. I will try and take some better ones when the fuselage is not attached.
 
   
 
 
 
 

If you have entered this page from outside the main home page please go here