Shop our Airplanes Products Drone Products Sales
Thread Tools
Old Oct 20, 2009, 04:24 PM
schrederman is offline
Find More Posts by schrederman
Hot Dawg Glider Pilot
schrederman's Avatar
Owl,

I just go over the rib area from one side to the next and continue wrapping. I'll usually wrap a couple of bays and touch it with CA so it doesn't lose tension and has to be totally redone if I slip. I try to wrap in one piece from start to finish, but wrapping one bay at a time would work just as well. I just wick in some thin CA on the sides, and let the glue wick in the spar cap areas when I'm adding the sheeting. Remember that excess glue is just weight. As long as the bay is wrapped, and the tow is well bonded, I believe no weak spot would exist.

In this case, the spruce/balsa was used in the outboard panels just to help keep the cost down. The Journey will have full-span CF spars. Now if I can just get those ribs...

I didn't get to see Richard's model before it crashed. It sure was pretty in the pics.

Jack
Last edited by schrederman; Oct 21, 2009 at 11:05 AM.
Sign up now
to remove ads between posts
Old Oct 20, 2009, 05:44 PM
Oldokie is offline
Find More Posts by Oldokie
Registered User

Spruce vs. hard balsa


For what it's Worth,

On my Houston Hawk I weighed the tapered spruce outer panel spar caps intended for the upper spar caps.

I then cut the same spar caps for the lower surface from very very hard 1/8 balsa.

Using a balance beam gram scale the weights were within 2 grams. The hard balsa being lighter by 1 1/2-2 grams.

My conclusion use the spruce.
Old Oct 20, 2009, 06:07 PM
schrederman is offline
Find More Posts by schrederman
Hot Dawg Glider Pilot
schrederman's Avatar
Good point... I never did that... Yep, use the spruce.
Old Nov 01, 2009, 11:46 PM
rnshagam is offline
Find More Posts by rnshagam
Registered User
rnshagam's Avatar
Thought I'd report on my Yardbird rebuild. Finished doing the center panel spar fishbone and have just now glued on bottom sheeting/trailing edge to the spar and rib tails. I've extended the spar by one rib bay on each side, so Jack might object to me calling it a Yardbird. I'd post a picture, but then you all will see how messy my garage workroom is.

Hope to have the center panel all sheeted up this week, then onto the mid panels. (I get to reuse my outer panels). And those spars are going to be made of out of spruce capped w/ carbon fiber strips. Want this next bird to last a little longer this time!!!
Old Nov 02, 2009, 10:49 AM
schrederman is offline
Find More Posts by schrederman
Hot Dawg Glider Pilot
schrederman's Avatar
I guess you could call it the Yardbird +... I'm looking forward to seeing it. I'll be out for the next TD competition.

Jack
Old Nov 02, 2009, 02:07 PM
atjurhs is offline
Find More Posts by atjurhs
agony sweetns the victory
atjurhs's Avatar
Quote:
Originally Posted by schrederman View Post
He likes sailplanes, guitars, fishing, nice cars, and good-lookin' wimmen... what else is there?

Jack
Ya got the makin's of a good country western song there Jack
Old Nov 02, 2009, 03:47 PM
schrederman is offline
Find More Posts by schrederman
Hot Dawg Glider Pilot
schrederman's Avatar
I think there has to be something in there about trains... but hey, I work for a railroad, so...
Old Dec 01, 2009, 12:00 AM
jimmm3 is offline
Find More Posts by jimmm3
LSF IV
jimmm3's Avatar
Jack, my Yardbird and I completed our LSF level 3 slope flight of 2 hours this weekend. I busted a wing tip at the Houston LSS, but a little TLC and some carbon fiber got the bird flyin again.

Jimmymac
Old Dec 01, 2009, 08:57 AM
rnshagam is offline
Find More Posts by rnshagam
Registered User
rnshagam's Avatar
Yardbird rebuild progress report
All three panels are pretty much framed up. Almost ready to shape leading edges. Still have to attach the old tip panels.

Jack, is the Yardbird a 'RES Woody -legal' ship for the SWC? I use an Art Hobby fg fuse, but the tail feathers and wing are mostly wood. I'm hoping to get it done in time for that contest in February--haven't signed up, yet. If not, I'll have to fly my ancient Sapphire or Jade again.
Old Dec 01, 2009, 09:42 AM
schrederman is offline
Find More Posts by schrederman
Hot Dawg Glider Pilot
schrederman's Avatar
Yes, it's legal. I flew mine last year. I was hoping to have the Journey ready for this year but still no ribs...
Old Dec 26, 2009, 11:12 AM
dong727 is offline
Find More Posts by dong727
Registered User

Yardbird Broken Wings


RNSHAGAM: Did you have the double D boxes with the .007 carbon fiber top and bottom in your intermediate panels? Did you wrap the joiner in the intermediate panels? Just curious - I'm very near completion of mine and would rather rebuild the outer panels than crash the entire sailplane.
Old Dec 27, 2009, 04:29 PM
rnshagam is offline
Find More Posts by rnshagam
Registered User
rnshagam's Avatar
dong727,
I used spruce for spars top and bottom, laminated with .014 cf on top and .007 carbon on the bottom. I also used tapered plywood doublers for the joiner box extending walls back two more rib bays from where the plans call for the end of the doubler--this is to avoid any stress risers like the one that took out the old wing. And of course, I wrapped the whole business with kevlar tow. Guess I'm not taking any chances again!!! If it breaks, its my own fault now...

Oh, and I should explain what I mean by tapered doublers. Fortunately, you asked just as I was about to cover my wing, so I was able to snap a picture for you--hope it explains it. Hope its not too late to make similar mods, if you can.
Last edited by rnshagam; Dec 27, 2009 at 04:39 PM.
Old Dec 28, 2009, 12:15 PM
dong727 is offline
Find More Posts by dong727
Registered User

Broken Wing


Richard: Thanks very much for the prompt response and photo! Your new wing looks truly bullet-proof. What I meant to ask was about your broken wing. Did it have the double-D section with the .007 carbon top and bottom as suggested in the Build Log? My wings are completed, covered and ready to fly. Meaningful mods are not an option at this point. If I want to change, I'll have to build whole new outer panels.
Regards, Don Grisham
Old Dec 28, 2009, 05:10 PM
dong727 is offline
Find More Posts by dong727
Registered User

Hot Dog Jack - Your Thoughts


Jack: My Yardbird is completed and ready to fly. I'm a little concerned about the outer wing panels. They are constructed as per the plans with the additional double D shear webs and .007 carbon. I also wrapped the joiner boxes with Kevlar. Do you think my sailplane is safe to fly in its present condition if I do not do "gorilla" launches? Your thoughts? If anyone else reads this and is successfully flying without carbon in the main spar, please chime in and let me know.
Regards, Don Grisham
Old Dec 28, 2009, 05:50 PM
schrederman is offline
Find More Posts by schrederman
Hot Dawg Glider Pilot
schrederman's Avatar
Don,

If you used HARD balsa in the outer spars, and I mean, the hardest, meanest stuff you can find, you should be OK for mild winch launches. If you didn't, I'd be careful.

Jack


Thread Tools