Billiken Fox Sti

[Billiken]

Hello everyone, I?m Jay and starting a Kitfox. In case anyone wants to know what a Billiken is, The Billiken is a mythical good-*luck figure who represents "things as they ought to be." It?s also the mascot for the school I attended. I am 2 months into the ?assembly? of my Kitfox. My background is almost exclusively that of a commercial pilot. 2 years ago I ordered this kit and began attending workshops and taking classes. My apparent greatest weakness is electrical systems. I plan to take the avionics class in Kansas City at some point. I am now at the building stage where small details are bugging me and I would enjoy clarification on some items. I flip flop between OCD and Looks About Right which leaves room for error. I just want to learn new skills that I can use in retirement.

[Billiken]

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My current dilemma has to do with the actual spacing between the rudder and the vertical stabilizer once adjusted by the rod ends. I initially set the rod ends for the dimensions called for in the manual. Once I hysoled the fairings in place, I had to extend the bottom rod end about a half inch to gain clearance between the fairings. The top seems ok. My question is, will this create a problem since it doesn?t match the specs in the manual? I?m guessing it doesn?t but I am trying to avoid getting too far off course.

[rv9ralph]

Because of the tail wheel springs being attached to the bottom of the rudder, there is a load on the bottom rod end. You need to get as close as possible. Is the fairing bonded touching the rudder post on the vertical?.

I had a gap under my fairing on the first bonding, I removed it and made the holes around the rod end attachments to clear the weld so I could get the fairing all the way against the rudder post.

[Billiken]

Because of the tail wheel springs being attached to the bottom of the rudder, there is a load on the bottom rod end. You need to get as close as possible. Is the fairing bonded touching the rudder post on the vertical?.

I had a gap under my fairing on the first bonding, I removed it and made the holes around the rod end attachments to clear the weld so I could get the fairing all the way against the rudder post.

Thank you Ralph. That is the potential problem I couldn?t see. I trimmed quite a bit of material for clearance at the bottom of the vertical fairing. The two weldments at the bottom that are close together did require a lot of attention. If there was a gap at the bottom, it was likely only 1 mm. I believe my clearance problem may be on the rudder fairing side. The process of removing the fairing is daunting, but not as much as not having it correct.

[Billiken]

This is the current setting of my bottom rod end. It was screwed in a bit more for proper gap per the manual.

[jiott]

When I built mine, I used the gap spacings specified in the build manual; but found later I had to increase them similar to what you did. After you get both surfaces covered and taped and painted it is surprising how much of the original gap is used up. Bottom line-don't worry about exceeding the manual specs, just get it as close as possible and be aware during the covering process to avoid any excessive build-up of layers and glue.

[Billiken]

When I built mine, I used the gap spacings specified in the build manual; but found later I had to increase them similar to what you did. After you get both surfaces covered and taped and painted it is surprising how much of the original gap is used up. Bottom line-don't worry about exceeding the manual specs, just get it as close as possible and be aware during the covering process to avoid any excessive build-up of layers and glue.

Thanks Jim, I completely agree with you. I admittedly was a little too hasty on the rudder fairing and created this problem. I have since removed the fairing and am preparing for pre-op surgery to carefully remove the Hysol from the wooden ribs. My greatest fear is damaging a wooden rib. I?ll report back hopefully in a few days on whether I was able to achieve factory specs again.

[rv9ralph]

One more quick thing. Don't file the rudder stop until you in final assembly. As Jim said, the gap changes with covering and finish.

[Billiken]

One more quick thing. Don't file the rudder stop until you in final assembly. As Jim said, the gap changes with covering and finish.

Thanks Ralph. I haven?t touched the rudder stop. I?ve seen a few videos where that was mentioned. I took your advice and removed the fairing with a low temperature heat gun and razor. It has since been refitted and Hysoled in place. I now have the gaps in spec with a beautiful swing. Thank you! I?m currently installing the tips. Foam block at the top and balsa for the horizontal. I wanted to try both techniques just to get the perspective. I personally favor the Balsa method. It reminds me of building airplanes as a kid and is more forgiving. I broke out the Superfil last night and tried it for the first time. It should be ready to shape today. I?m working exclusively on the tail because I still want to paint some of the cockpit cross members flat black. That project is becoming complicated for the fact that I would like the finish to be maintenance free. I think it?s going to require primer and a really tough enamel. My next big hurdle is coating the foam block with hysol. It seems like it would be relatively easy but the foam is so delicate that I?ve already broke a piece that was shaped.

[jiott]

Try to get the Hysol on the foam as smooth as possible (within reason) and without much extra, because Hysol is very tough and is hard to file and sand, compared to SuperFill which is a dream to sand and shape. Use the SuperFill for final finish on the Hysol imperfections.
You could use only SuperFill, but it has little strength to protect the foam from bumps and bruises.