Saturday, July 11, 2015

Prepping Parts For Primer

In addition to needing to prime the spacers used for mounting the trim servo assembly and the two replacement F-1256 links for the right rudder, decided it would be wise to just take the time now and prime the parts for the wheel pants as well. The prep and cleanup takes a considerable amount time so want to make it worth while. Also picked up a different style air brush which looks promising for spraying the primer. It appears as though it is capable of spraying more paint which will be good for the larger pieces needing primed. With the exception of the newly received powerplant kit, this should complete all the priming of parts firewall aft.

In the wheel pants kit there is one piece that needs to be separated into a left and right U-00006A brackets and a few other parts that require a light edge deburring.  And then there are the four U-00002 wheel faring brackets which require some serious attention. These are very thick brackets that were sheared during the manufacturing process and have large burrs and sharp edges from the shearing process. In addition, the brackets have taken on a curve from the shearing and hole punching process … this curve needs to be taken out by the builder so the brackets lie flat on a flat surface between the offsets on either end of the brackets. I found supporting the ends of the brackets between two blocks of wood and whacking the high point with a soft faced mallet eventually beat the metal into submission and relaxed the bow.

After the U-00002 wheel faring brackets were deburred and straightened, there are nutplate rivet holes on both ends of the brackets that require machine countersinking with a #40-100 degree countersink bit. Machine countersinking these holes can be tricky because the countersink cage hangs over the edges of the metal … suggest doing this in small increments and sneaking up on the proper depth.

Using the air drill outfitted with the countersink cage and a #40-100 bit to machine countersink rivet holes in the U-00002 wheel faring brackets that will be used to mount nutplates.

The last items in the wheel pants kit requiring attention are the two U-00006B splice strips. Both strips come with a note affixed to enlarge the 13/16" cutout to 1".  The two strips were Clecoed together and punched down onto some Styrofoam a socket with a diameter of 13/16" was placed into the existing cutout so the center point could be located and marked. Next a socket that measured 1” diameter (turned out to be a 3/4" socket) was placed over the center point and the outside of the socket was used to mark the cutout for metal removal.
Both U-00006B splice strips Clecoed together and the after the center point for the existing 13/16" cutout was determined, a socket with a 1" diameter was positioned over the center point and the outer edge of the socket was traced onto the splice strips to make the cutout larger.

Now that the new 1" cutout is marked, while the two spice strips are still Clecoed together, a Dremel tool with a sanding drum will be used to grind down the excess material and then the splice strips will be ready for primer.
Box of goodies ready for cleaning, a good scuffing with Scotch-Brite pad, more cleaning then primer … have to remember to also add the two new F-1258 links in the primer tray as well.