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Doran Jaffas

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Jun 25, 2019
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Installed new tires and tubes yesterday. Found an item that needs to be checked during every preflight. The gear leg, I will call them pin bolts on the gear, of the Tailwind need to be checked. After raising up the gear legs individually to replace the tires I found that there was some wobble in the gear legs. Tightened up the bolts and no issues. May have been there for 20 years as I'm not the builder but I'm going to order some close tolerance bolts and if necessary ream out the holes to fit. Again I don't think this is a big issue because they snugged up easily but something to be aware of for any body that has Tailwinds.
 

Pops

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Installed new tires and tubes yesterday. Found an item that needs to be checked during every preflight. The gear leg, I will call them pin bolts on the gear, of the Tailwind need to be checked. After raising up the gear legs individually to replace the tires I found that there was some wobble in the gear legs. Tightened up the bolts and no issues. May have been there for 20 years as I'm not the builder but I'm going to order some close tolerance bolts and if necessary ream out the holes to fit. Again I don't think this is a big issue because they snugged up easily but something to be aware of for any body that has Tailwinds.
Had the same problem with the round gear legs into brackets on the wing spar in my Falconar F-12. Welded 3/8" thick bushing on the outside of the bolt hole on the bracket to solved the problem of wear.
 

Dana

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Took the tailwheel assembly off the plane, I've been getting some bad shimmy. I rebent the springs by clamping them in a bench vise using a big monkey wrench with all my weight hanging from it and bouncing. Scary. Got about 4° more angle. Then I disassembled, cleaned, and greased the swivel assembly, and machined a 5° angled spacer to replace the original 1½ to 1¾ spacer (the one in the back in the pictures). That may be too much, I'll see after I get it back on the plane tomorrow, I can always machine the spacer back to less angle.

1615165795511.png

1615165815987.png
 

Chris Matheny

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Nov 26, 2019
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St. Paris OH
Started learning how to tig weld this weekend. I always wanted to. Have to build a sheet metal intake and turbo piping for my engine anyways so figured I would learn rather than pay someone to do it for me. I have a long way to go but I actually kind of enjoy it.
 

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Doran Jaffas

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Jun 25, 2019
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474
Took the tailwheel assembly off the plane, I've been getting some bad shimmy. I rebent the springs by clamping them in a bench vise using a big monkey wrench with all my weight hanging from it and bouncing. Scary. Got about 4° more angle. Then I disassembled, cleaned, and greased the swivel assembly, and machined a 5° angled spacer to replace the original 1½ to 1¾ spacer (the one in the back in the pictures). That may be too much, I'll see after I get it back on the plane tomorrow, I can always machine the spacer back to less angle.

View attachment 108296

View attachment 108297
This might be a stupid question but is that teal wheel assembly off of W10? Looks pretty heavy duty.
 

Mark Z

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Aug 29, 2012
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747
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Granbury, Texas USA 0TX0
I’ve got a box full of older Craftsman stuff that is perfect!
My present project is filling a toolbox for a school kid going to TSTC as a maintenance tech. The CPS forum folks have more than stepped up to the plate.
 

Toobuilder

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Got the Rocket buttoned up enough to go flying. Still have some non structural fairings to install around the augmentor tubes so the performance measurements are not there yet, but I beat on it pretty hard and nothing fell off! I did take temperature measurements on the floor and those seem to have come WAY down, so that box is checked.
 

gtae07

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Dec 13, 2012
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Savannah, Georgia
Finished tailcone avionics bay wiring/conduit
Final installed elevator bellcrank and AP servo arm
Riveted on the other aft upper skin, with wife's help

Next is cleaning up the shop (it needs it bad) and then maybe landing gear installation
 

Pops

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W10??? It's on my Hatz.


Yup, just not as pretty... it's an old one, 1980s vintage, when Craftsman still meant quality.
1980 is old ? I have socks that old. :) Let me see ? Yes, that was 7 years ago. Love your Hatz.
 

Dana

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Flew last night. The re-bent spring plus the angled shim was clearly too much once I got it mounted, I figured I'd at least taxi it too see how it behaved... definitely too much. Put the straight shim back in, much better, not a trace of shimmy.

Right now there's about 9° of negative caster, as near as I can measure it, with half fuel and nobody in the seats. It might still be a wee bit too much but I'll wait a bit to see if the spring relaxes during the next few flights, if not I can machine the shim back to a lesser angle and install it the opposite way. Alaskan Bushwheels recommends 5-7° but I think it was about 5° before when it was shimmying badly. Of course cleaning and regreasing the swivel assembly no doubt helped also. I guess I'll just have to go flying again to see... oh, the burden!
 

N804RV

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Jun 9, 2013
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Mount Vernon, WA
Legs are mated to fuselage. Now, I can fit the forward bottom skins and finish riveting the forward skins before "flipping the canoe" for the final time.

I'm really impressed with Van's engineering and production. And, with the quality of the Ken Krueger's SkyDesigns aluminum airfoil landing gear. I squared the legs up using 4 foot levels clamped to the outboard faces of the lower legs. The measurements fore and aft were exactly the same, meaning there is no toe-in/toe-out. And, by dropping plumbs down from the outboard bottom leading edges of each leg and one from the center tooling hole of the aft bulkhead, I was able to measure the distances on each side. They were also exactly the same. I could not measure even 1/32" difference over more than a 10' span. That is impressive accuracy! The legs are on very precisely square to the fuselage center line.

 

Pops

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Flew last night. The re-bent spring plus the angled shim was clearly too much once I got it mounted, I figured I'd at least taxi it too see how it behaved... definitely too much. Put the straight shim back in, much better, not a trace of shimmy.

Right now there's about 9° of negative caster, as near as I can measure it, with half fuel and nobody in the seats. It might still be a wee bit too much but I'll wait a bit to see if the spring relaxes during the next few flights, if not I can machine the shim back to a lesser angle and install it the opposite way. Alaskan Bushwheels recommends 5-7° but I think it was about 5° before when it was shimmying badly. Of course cleaning and regreasing the swivel assembly no doubt helped also. I guess I'll just have to go flying again to see... oh, the burden!
Someone has to do it.
 

Toobuilder

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OK, so I have some time flying the new augmentor tubes and have been able to determine that I have not lost any speed even with an unfinished lower cowl. I've been flying with the augmentor bay "open", which provides a very messy aerodynamic scenario as illustrated below:

Cowl OML rear.jpg

Note the huge pocket that the antenna lives in... That step from the lower cowl OML to the bottom of the fusealge is 5 inches deep. The intent is to add a lower failing which will continue the cowl OML in a nice spline line to terminate at the transponder antenna.

Yesterday I did an oil change and of course despite my best intentions, oil went everywhere. Post oil change flight showed the oil migrate out and provide me with a great visualization of the flow pattern under there. (should have taken a picture, but was too embarrassed to show the amount of oil). Anyway, as expected, the pocket around the antenna was a turbulent mess and showed a chaotic pattern of airflow. But surprisingly, the airflow straitened out quickly, and was showing signs of organization even in front of that angle bracket running perpendicular to the flow direction. Behind the bracket and between the pipe exits, the airflow was showing a nice high velocity pattern that was somewhat pinched between the tubes but otherwise doing what "seems" like the right thing.

I have some cross country work in the near future so it will be interesting to see the results of this aero mess is on real world performance, but it seems like there should be a little speed hiding in there somewhere. I'll let you know what happens when the fairing goes on.
 
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