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Building Tips and technical articles. => ARF'S => Topic started by: bob branch on November 02, 2018, 07:48:15 AM

Title: .60 size brodak leadout question
Post by: bob branch on November 02, 2018, 07:48:15 AM
I am for info based on EXPERIENCE, not theory, of the leadouts on the 2 piece winged Brodak .60 planes. I built a number of them when they first came out with one piece wings (except T Rex which always had 2 piece wing). I am doing another Strega  and noted the leadout securing method has changed back to moe traditional Brodak method. Does anyone know of a leadout failure on one of the 2 piece winged planes, arf, or arc. Since I am ready to start on the wings its important I get an answer asap. I know by theory, and by my own practice I would normally redo these attachments to wrapped security. But I don't want to do work for no purupose.

Also, can someone tell me when the 2 piece wing started to be produced on these planes. btw, this airframe appears to have better workmanship than the earlier ones.

Thanks, returning to cl I hope,  bob branch
Title: Re: .60 size brodak leadout question
Post by: Carl Cisneros on November 02, 2018, 10:25:40 PM
Bob
i used the strega wing for my 60 sized Sakitumi 60+ I built this year.
I re-did the lead outs from what was in teh 2-piece wing to the copper tubing method
thru the bellcrank with the wire going thru the tubing.

I did not like the wire that was originally in the wing and the crimping method that was used.

Carl

hope that made sense
Title: Re: .60 size brodak leadout question
Post by: John Paris on November 03, 2018, 03:48:26 AM
Bob,
Good to hear that you are working with some airplanes again.  I have not heard of a failure with the 2 piece wing version of the Brodak ARFs and the construction looks robust enougb.  I did redo the two I have built just because I did not like the almost 90 degree bends at the bellcrank.  I think the 2 piece wings have been around for at least 8 years.

Hope to see you in the circles next year.

Regards,
John
Title: Re: .60 size brodak leadout question
Post by: Shug Emery on November 03, 2018, 09:34:14 AM
I have been flying my Brodak Strega ARF quite a lot and did not alter my leadouts. Still going strong. Got the Strega in 2015.
Shug

https://youtu.be/v3pfZOI7X8Q (https://youtu.be/v3pfZOI7X8Q)

https://youtu.be/JRhqEdsb9Rw (https://youtu.be/JRhqEdsb9Rw)
Title: Re: .60 size brodak leadout question
Post by: Air Ministry . on November 05, 2018, 05:28:44 PM
With the TWO PIECE WING type ,

making a STRONG wire U or V , with Us orVs on the ends , :P

You can suport the belcrank pivot , or maybe better just the LEADOUT ( One at a time )
and pull the living snot out of Just Them . To see if theyre seaworthy & shipshape BEFORE
you do anything silly . Like joining the wing halves .

Id put new ones in the AFC Strega , mainly as they wernt as weighty or draggy , and ended up doing all the controls .

But the 3 mm plated wire horns supplied were accetable & being short , light & ridgid .
As I was typing the above , i went . . . oops . You wouldnt want to suspend your weight on the widdle paxilon bellcrank .
Hence the comment .
Tho if I recall , Ive suspended my 10 or 11 stone , on I think ONE 18 thou Laystrate lead out . The planes unlikely to pull that much .

Just Testing . Might try it on the strega Ones , back home .  VD~ from the rafters .
Title: Re: .60 size brodak leadout question
Post by: Air Ministry . on November 08, 2018, 07:50:14 PM
RIGHt , well then .

Chucked one ofthe 4 mm undercarage legs thru the loop , as shown , No 1 .

Wrapped four times round the lintel , played tarzan .
Estimate 100 Lbs ish ' fail ' of mid grade ? wire .WhyIsaythatis sounded progressive - 1 or 2 first ping zang , not all nicen even .

Anyway , Awkward grip between 2nd & 3rd fingers ( and the 1st & 4th ) about the 4th attempt attepted full weight with practised grip .

LAST shot is POST EVENT , appears no deformation or dislocation from Original , in the ' End Detail .

So appears the assembly is adequate , though ya needta clamp up the nuts adjacent the bellcrank to loose the rock , as supplied /

Asivesaid , I replaced it all with ' in shop ' custom self made tripe , with Ditto spar joiners & Ply Bolt posn. reinforcers .

So this was all in the left overs box , unused .
I did so bellcrank was uninvolved in the destructive tendancies, so unstrained .

Cant really see the plane pulling 200Lb in mid air ,  and if ONE line breaks
they generally loose centrifugal force going round in tight loops , so under 100Lb their . Likely 50Lbs as high as itd go ,
Yet to fly mine , will letya know if I end up in the next field downwind .

 H^^