Thread Tools
Feb 04, 2019, 08:06 PM
Registered User
Thread OP
Build Log

Durex V by YellowBlueBird

This will probably be more of a request for help than a "how to do it". Some images to start with.
The first question that I have is, Does anyone sell a bell crank that will work with the stabilizer.
If things go as scheduled the lumber list will be ready tomorrow.
The images are not in the right order and they don't want to move as directed.

Sign up now
to remove ads between posts
Feb 05, 2019, 03:16 AM
Balsa breaks better
Thermaler's Avatar
If you can't find a Craft Air bell crank you can make one from 1/16" or 3/32" plywood.
You could get fancy and used fiberglass or carbon plate also.


Balsa breaks better - Woodies Forever.
Feb 05, 2019, 04:00 AM
Registered User
Good to have a bit of extra thickness at the pivot to prevent the wobblies.

You might find something suitable at one of the control line supply places. OTOH, if you can find some sort of screw together bushing to keep things square, a piece of plywood or fiberglass might be fine.

Might be good to put some kind of reinforcing scab let into the balsa the pivot pin comes out through. The pins on many models have a tendency to chew up the wood until the stab wobbles a bit. Not fatal, but annoying.
Feb 05, 2019, 05:36 AM
Registered User
whacker's Avatar

Nice Version, of a Toggle clamp

Belcrank of "good"ply, with a collar will work.

2 layers of 1/16 ply, perhaps with a CF filler in a samwich, also a Good Option

Nice toggle clamps, gonna keep an eye on this Build

The Short Kit looks to be well done.

Feb 05, 2019, 08:59 AM
Kurt Zimmerman ≡LSF 4461≡
kzimmerm's Avatar
Bellcranks can be easily fabricated from scrap pieces of Formica which I have done on quite a number of occasions.

If you go that way you can also make spacers that are placed on either side of the bellcrank and the fin sides to keep it centered. I found small pieces of red Nyrod material works best. This keeps the bellcrank from walking its way to one side of the fun with the risk of binding
Feb 07, 2019, 09:29 PM
Registered User
Thread OP

Durex V

Not much work on Durex V this week due to 80 degree February weather. One of my sailplane buddies called and asked me to come out to the city park. He gave me a sailplane kit and refused pay for it. Just asked that I build it and come fly with the group.
Feb 07, 2019, 09:44 PM
Registered User
Thread OP
A good bit of time yesterday gathering parts. This is what nineteen dollars worth of brass tubing and music wire looks like.
Feb 07, 2019, 09:54 PM
Registered User
Thread OP

what happened to the comments to the above images?

The first image is what 19 dollars of tubing and music wire looks like.

Second image shows the lamination used for the leading edge of the rudder.

Next one shows adding lamination to the other side. Note the spacer under the trailing edge to keep the parts lined up.

The last image is an oops by the laser cutter. The I/32 plywood side for the bell crank box was cut even with the top of the fuselage. It must go through the 1/4 inch top sheeting . Easy enough to cut another one. The top of the pencil shows where it should come to.
Feb 08, 2019, 04:35 AM
Balsa breaks better
Thermaler's Avatar
If it were me and I was not going electric I would consider doubling the the size of the front wing joiner and moving it from the sub-spar into the spar with a box.
I would also consider moving the rear joiner into the spar and a box also.

But I have a heavy foot on a winch too . . . I bent a 7/32" joiner on my Wanderer 99 several times before I drilled it out and went to 3/8" . . . YMMV ;>)

Feb 11, 2019, 10:47 AM
Registered User
Thread OP

the lumber list

bit the bullet and sent it in. No more looking at the plans to see what I missed.
Feb 11, 2019, 11:11 AM
Registered User
Thread OP
Whacker; Does the plywood wear where the clevis attaches.
What did you use for the reinforcement. looks like a rivet. there is a piece of 5/32 in my box of leftovers that is about the right size. It is a bit scary that this thing gets sealed in. I wonder if a bell crank could be cut out of a piece of stainless steel?
Feb 27, 2019, 11:41 AM
Registered User
Thread OP

Tail feathers assembled

This turned out sturdier than expected. Almost ready to sand.
Mar 04, 2019, 11:34 AM
Registered User
Thread OP

Time to select a power plant

What size motor and speed controls are you guys using on this size sailplane?

Quick Reply

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Durex V yellowbluebird Thermal 4 Feb 05, 2019 03:42 AM
Discussion Durex V yellowbluebird Sailplane Talk 4 Jan 30, 2019 01:35 PM
Discussion Durex V - First Stratch-Build / First Glider pappy35 Thermal 33 May 15, 2017 08:16 AM
Build Log Durex V trident58 Thermal 126 Dec 08, 2013 09:31 AM
Discussion Durex V Mirage1 Thermal 8 Mar 09, 2007 10:22 PM