Originally Posted by Belginique

Now that I have added a bigger tail wheel, my CG is around 5" and I like it a lot. I can get it to do some crazy spins now.

Bye the way, AKNick, your tail bracket is brilliant (https://www.thingiverse.com/thing:4484038).
It is a perfect fit. I used a slightly smaller wheel because that is what I had lying around. The ground handling is better than with the tail wheel that came with the kit. I could even re-use the original springs. Thank you!

THANKS!!! Glad you like it! It's always heartwarming to see something I created being put to use! Excellent print quality by the way. One thing I'd add to your printed part is to sleeve the hole (ie: brass tubing) where the wire passes through, otherwise it'll cut into the plastic over time.

Originally Posted by Buck Tracker

Hi guys,
making progress on my Timber. I wanna replace the extremely stiff springs on the x-cub gear with something a little softer, any suggestions??
TIA

I've seen guys put softer springs on it and then regret it. Most guys need the prop clearance. One thing I've noticed with all the plopping... I mean STOL landings.. that they actually wear in a bit overtime and get softer. Also, most people (including myself at first) thought they were incredibly stiff.... BUT after you add the 20# airplane on them - they have more cushion then felt before (ie: set the plane on the ground with the wings on and rock it to watch them work).
On a different note rubber bands fail... ask anyone who owns the H9 PA18-150 and they'll tell you what a pain they are. You can go to the fabric store and buy elastic bungees that would probably hold up better.
Another thought is to take out the OEM spring, measure it, and use a fish scale to figure out the pulling force over a certain distance and go to the hardware store and find a suitable spring that is less stiff under the same resting and pulled condition. Otherwise Look up springs online and use their dimensional charts to fill in what you have and find one that's suitable.

Originally Posted by AKNick

I've seen guys put softer springs on it and then regret it. Most guys need the prop clearance. One thing I've noticed with all the plopping... I mean STOL landings.. that they actually wear in a bit overtime and get softer. Also, most people (including myself at first) thought they were incredibly stiff.... BUT after you add the 20# airplane on them - they have more cushion then felt before (ie: set the plane on the ground with the wings on and rock it to watch them work).
On a different note rubber bands fail... ask anyone who owns the H9 PA18-150 and they'll tell you what a pain they are. You can go to the fabric store and buy elastic bungees that would probably hold up better.
Another thought is to take out the OEM spring, measure it, and use a fish scale to figure out the pulling force over a certain distance and go to the hardware store and find a suitable spring that is less stiff under the same resting and pulled condition. Otherwise Look up springs online and use their dimensional charts to fill in what you have and find one that's suitable.

Thanks for the tips Nick
My hope is that I will be under the 20lb mark by a bit, PMT's and GP 38
Will see I guess, gonna find some slightly softer springs and start there, if they suck I'll put these back on. Also swinging a 21x8 so I'm starting out with a little more clearance than some.

Nick,
Are you selling your 3-d printed tail wheel bracket?
Thanks,
Gary

Originally Posted by Buck Tracker

Thanks for the tips Nick
My hope is that I will be under the 20lb mark by a bit, PMT's and GP 38
Will see I guess, gonna find some slightly softer springs and start there, if they suck I'll put these back on. Also swinging a 21x8 so I'm starting out with a little more clearance than some.

True, I have the DLE55RA, XCub PRs, and wieght in the tail... My plane is actually 21-22#

I stole this from myself from another site (G S N)

Okay I decided to re-weight my plane for ya'll.

DLE55RA, Falcon 23x8CF, 3" center bolt spinner, 2 pulse 2550's, XCub Gear, 8.75" PR Bushweels, 3.25" Dubro Tail Wheel... SIX ounces of sticky weights in the tail.

Per my fish scale.
20.7# empty w/out struts-batteries-fuel-slats
21.0# empty w/out struts-fuel-slats w/batteries
20.9# empty w/struts w/out batteries-fuel-slats
21.4# empty w/struts-batteries w/out fuel-slats
21.9# Loaded w/ 17oz fuel-batteries w/out struts/slats
22.0# Loaded w/17oz fuel-batteries-struts w/o slats (my bathroom scale says it's about 22.3#) FWIW the struts weigh 0.3#

CG 5.125"(5-1/8") w/batteries w/out struts or fuel (tail level flight)
CG remained very close to the same with fuel and struts to my surprise shifting slightly towards the nose coming in at 5"

Shoot for the aft window post for starting CG, mine is just at the aft part of the cabin window post (plastic painted yellow).

Originally Posted by Redjack

Nick,
Are you selling your 3-d printed tail wheel bracket?
Thanks,
Gary

I'm not selling it per say. Posted it on Thingiverse for others to download and source their own hardware.
https://www.thingiverse.com/thing:4484038

I can print one and sell it, but I'm afraid all the fine tuning involved would drive people crazy. You have to sand and trim a bit to get it to fit your OEM tailwheel leaf assy. My hardware stores are probably more expensive than most of you guys in the lower 48 as well. I think I've made an estimate to what it would cost and it would be about the cost of an XCub tailwheel assy... possibly more after materials, printer time, and shipping. So to be honest, It's not exactly worth my time. I would feel bad if someone had me print one and ship it without cleaning it up just to accidentally break it. If it's something you (or anybody else really wants from me, I'm sure we could make it happen). I think anyone who has printed one can attest that it's time consuming to print, clean up, and fit... but maybe they are better at 3D Printing than I am LOL...

I think I got lucky today, first hardware store I checked had a bunch of extension springs. The stock springs are .077 dia wire and these are .066
Just a little more give but not a lot.
Next up, sanding and repainting the gear...

Hey Nick,

Working on my rudder set up, used the 3.5" offset like you recommended, geometry is perfect but the cables really rub on the opening of the fuse. I enlongated the slots as far as I could right up to the former but they still rub. Any thoughts??

Originally Posted by Buck Tracker

Hey Nick,

Working on my rudder set up, used the 3.5" offset like you recommended, geometry is perfect but the cables really rub on the opening of the fuse. I enlongated the slots as far as I could right up to the former but they still rub. Any thoughts??

Hmmmm. You crossed the cables too yeah? Can you go inboard one hole on the Servo? I'm using the outboard control horn holes as well.

Originally Posted by AKNick

Hmmmm. You crossed the cables too yeah? Can you go inboard one hole on the Servo? I'm using the outboard control horn holes as well.

Yup crossed them, outboard holes at rudder. I'll try one hole in on the servo arm see if that helps

So played around a bunch just now and I couldn't have ended up with a completely different setup than were I started. Uncrossed the cables, stayed in the same outer hole on the offset arm at the servo but moved to the inner hole on the rudder. Zero cable slack thru entire range of travel and minimal contact on the fuse. Still a slight amount though but only at max throw. Only thing I do not like is instead of upping my travel end points I had to reduce them down to 80% for max throw before it contacts the elevator.

Originally Posted by Buck Tracker

So played around a bunch just now and I couldn't have ended up with a completely different setup than were I started. Uncrossed the cables, stayed in the same outer hole on the offset arm at the servo but moved to the inner hole on the rudder. Zero cable slack thru entire range of travel and minimal contact on the fuse. Still a slight amount though but only at max throw. Only thing I do not like is instead of upping my travel end points I had to reduce them down to 80% for max throw before it contacts the elevator.

Wildness.... Could your servo be in the opposite direction than mine? My output shaft is fwd. Dunno

Originally Posted by AKNick

Wildness.... Could your servo be in the opposite direction than mine? My output shaft is fwd. Dunno

Ya weird for sure and no, mine is forward as well. Check your cables where they exit the fuse and see if there are rubbing, I'm curious is all. I am relatively happy with the outcome, being that this is a docile slow moving bush plane.

Finally gonna mount the Xcub gear later today, sand blasted it and painted so it's looking sweet!

Got her up on the gear finally, really happy with how it's turned out so far!

Small progress, new strut attachment point complete