Carlson Skunk Works

April 16th, 2010

AMF-14H Maranda SN:1026 Construction Log April 16, 2010

Posted by Roger in AMF 14H Maranda SN1026, news

WOW! This is the first I have posted since November?! Well, all I have to say in my defense is that I have been busy and I am making progress. As of this posting, the vertical fin and rudder are DONE! Unfortunately, I don’t have any pictures of them. In fact, this is just going to be a short text entry.

Like I said, the fin and rudder are done. I may do a bit of sanding on them before I cover them, but that will probably wait for awhile.

The leading edge of the rudder and the tops of the rudder and fin have balsa blocks glued to them which were then shaped with a block plane and sandpaper to make them look good. Then everything was sealed with a fairly heavy coat of sanding sealer.

I used the Stewart Systems sanding sealer and sealer applied with foam brushes. This worked pretty well, but next time I am going to try some bristle brushes instead. The foam brushes didn’t hold up very well and when they started breaking down they left little chunks of black foam sticking to the finish. That is one of the reasons that I expect to sand the surfaces before I cover them.

The Stewart Systems sealers are really nice to work with! They are water born, so they are very eco-friendly, they have no smell and they clean up with water. These are not inexpensive, but I think I will continue to use them because of the lack of odor and the easy clean up. I bought two versions of the sealer. The sanding sealer is used first to seal the wood and fill the grain, then the sealer is used as a second coat to make things look good. It does a very nice job.

Since summer is coming, I thought it would be a good idea to move my work area to the garage and work on something a bit larger, like the wings. I grabbed a bunch of the ribs that I had assembled and went to work sanding them. When I started counting them I found out that I didn’t have as many as I thought I did, so I have gone back to building ribs for the past couple of weeks. At this point I have to build two more short ribs, but I have all the parts cut and it is just to do the gluing.

When the ribs are assembled, I will take them to the garage and go about sanding them. I have decided that I will put some small boards through some of the openings and clamp them together as a single group, then use my belt sander to smooth them down and to the proper shape. Once that is done I will need to cut a notch in the nose of each rib for the leading edge cap strip to go into. I will also need to cut the trailing edges all the same and cut a notch to accept the gussets that will hold the trailing edge strip to the ribs.

I made a mistake when I built the spars! Somehow I got a bit mixed up and used 1.5mm plywood instead of the 2mm plywood called for in the plans. The width is not so much of an issue as is the number of plies in each. The 1.5mm plywood has 3 plies while the 2mm plywood has 5 plies. This will mean that I will have to split the front spars and remove the old plywood, then replace it with thicker plywood. The easiest way to do this is to use the planer to remove the plywood down to the fir. Because this may result in removing a bit of the fir, I am planning to use 3mm plywood for the webs.

Well, it looks like I have my summer work cut out for me. Hopefully, I will still be able to update this blog periodically and include some pictures.

Until next time…