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  #11  
Old 01-18-2021, 05:44 PM
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Quote:
Originally Posted by dlazarus6660
Thanks for the post.

I am a long time R/C modeler with years of hanging hinges on model airplanes.

What I was thinking is replacing the ball with the hinge by cutting the tube in half, inserting the hinge in one side of the tube and inserting the hinge in the other tube, then attach the tube to it's proper dowel(s).

My question is, how does the hinge stay in the same plane without it twisting or torqueing out of shape? Does that make sense?


Like so (pic 1)? I wonder if the side plates would provide guidance to make the hinge stay in-plane rather than torquing? Plus the tubing provides some alignment flexibility, right?

Not sure of dimension the hinge...I was using Mk1.0 eyeball from the web picture and scaling against the thumb But it looks like you'd have to trim the length the hinge "legs" to fit in the given space.
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  #12  
Old 01-19-2021, 06:47 AM
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Quote:
Originally Posted by georgegassaway
I'd be concerned about the Robart hinges breaking in a really hard landing. Repairing anything inside the ML's leg system is a huge PITA (From what others have mentioned in the past).


When I tried the Robart hinges in my Outlander, one broke on the first flight, so avoiding them is the right approach, IMHO.
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  #13  
Old 01-19-2021, 07:14 AM
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I know my photos are gone thanks to the new owners of Photobucket, but I think the best way to build the ML is to use the included ball and tube hinges and make the rear bulkhead removable. I did mine that way so that I would have access to replace rubber bands. Sometimes springs end up stretching too, so I'd still make the bulkhead removable. Mars Landers should have four balls.
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  #14  
Old 01-19-2021, 08:47 AM
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I have built at least 5 Mars Landers and I second what tbzep said just above.
Robart hinge points are great at their intended usage, but lousy for this application.
Not designed to handle the direction of stress from Mars Lander legs.
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  #15  
Old 01-27-2021, 02:48 PM
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All you guys are great!

Thanks for all the advice.
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  #16  
Old 01-27-2021, 07:34 PM
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Quote:
Originally Posted by GuyNoir
When I tried the Robart hinges in my Outlander, one broke on the first flight, so avoiding them is the right approach, IMHO.


I was wondering which size hinge you used?
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  #17  
Old 01-27-2021, 09:49 PM
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Quote:
Originally Posted by tbzep
I know my photos are gone thanks to the new owners of Photobucket, but I think the best way to build the ML is to use the included ball and tube hinges and make the rear bulkhead removable. I did mine that way so that I would have access to replace rubber bands. Sometimes springs end up stretching too, so I'd still make the bulkhead removable. Mars Landers should have four balls.


After seeing Tim’s photos “way back when”, I did the same mods to my Semroc Mars Lander. And I did mine after it was built. I waited until it crashed, and one leg had broken. I did not have any damage to the flex tube or dowel, the break was below that. I did use a new rubber band since it was opened up. I have another kit, and will build it with the standard hinge system like the first. I’ll also leave it 18mm, since I fly my currect lander on the D13 reload in the 18/20 RMS.

I converted my Outlander to 24mm,and the hack is not too bad, but not worth the effort in my opinion, since the D13 reload works so well. And the Q-Jet Ds should work well, though they only have about 2/3 the N-s of a D13 reload.
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  #18  
Old 01-28-2021, 07:10 AM
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Quote:
Originally Posted by LeeR
I converted my Outlander to 24mm,and the hack is not too bad, but not worth the effort in my opinion, since the D13 reload works so well. And the Q-Jet Ds should work well, though they only have about 2/3 the N-s of a D13 reload.

And we now have the C5-3 which should be good for smaller fields.
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  #19  
Old 01-28-2021, 09:19 AM
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I ordered 20 paks of C5-3s not long ago.
I'm NOT going to run low on those again. EVER.
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  #20  
Old 01-28-2021, 09:50 AM
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Quote:
Originally Posted by ghrocketman
I ordered 20 paks of C5-3s not long ago.
I'm NOT going to run low on those again. EVER.

Me neither.
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