Bidule 170 Len's Thread

[lenb]

This servo saver system has been flawless in my Bidule. Once it was installed we have never had to do anything else to it. Total about 60 hrs of use.

[Mac Powell]

Thank you for all the wonderful pictures.
I purchased all the Losi parts and plan to follow your example.
How tight did you make the spring? Looks like it is down quite a ways.
Thanks again,
Mac

[lenb]

Hi Mac,
Honestly, make the spring as tight as you can, it will STUN you how easy it will still be to move even cranked down tight. You see about three to four full threads on the shaft.

[Helijet]

awesome thread!!! thanks for the info.

​Dean

[lenb]

CHECK OUT THESE BRAKES FOR THE BIDULE (and others)

http://forum.scalesoaring.com/forum/tugs-and-stuff/tow-planes/8175-bidule-170-hydraulic-brakes-can-fit-other-big-tugs-too

[lenb]

The initial setup was pretty much stock, and it sucked. The aluminum steering push rod provided has a rubber lord mount located in the middle to act as a shock absorber and give the rod a break point. Since 100% of our flying is done off of fields that are not always the smoothest, we're tough on the nose wheel.
Pretty much every weekend out we were working on the steering or at least replacing a servo. The metal arm is cheap China-metal, so its a matter of time until it failed. Bob M made up some 1/8 thick steel replacements which have been trouble free since installation.
The problem with the steering system needed to be addressed if long term viability was to be realized. Scot stepped up and designed and built a prototype of a servo saver system using 1/5 scale truck parts which has been flawless since the day we installed it in the plane. PROBLEM SOLVED.

Here are some photos of the parts

[lenb]

Photos of the actual parts

[Stew2]

What are your thoughts on what control lever on the transmitter to actuate them from? Is the axle diameter increased at all? The breaks do move the wheels out a bit, increasing bending loads on the axle. The good news is that the Bidule and typically your landings are very gentle, so there should not be excessive force, but if I were flying...... Axle strength could also be combated with an up-tick in material choice also. I think the break design is fantastic and really look forward to seeing how they perform, but my money is on the design and designer with this one!! Also interested in seeing what the holding power is with engine run up, but promise me, no stupid choices like thinking that at any time it would be smart to let the brakes hold the plane for engine start.

[lenb]

Hi Scot,
The design is solid for sure. Axle size is larger than the original supplied axle, ( which bent ) however the attach hole in the gear is a bit smaller but Gunny provided a bushing which gets epoxied in. This is a great idea because it provided a metal sleeve for the threaded parts vs a carbon hole which would where if the gear axle ever became loose. Good idea there.

The holding power of the brakes should be excellent. We fly mostly from grass, so I imagine even with the wheels locked up I can power up and slide the wheels on the grass. We'll test that this week and see.
These are not toy motors we're playing with, so like you say no using the brakes to hold the plane while starting. Huge motors + Carbon blades= no more flying for you.

As for the control choice, I've opted for a proportional control and have it set up on the right side slider. My thought is because its a nose wheel aircraft, the right hand is doing nothing once on the ground and can easily operate the lever without taking away from other controls. Throttle and steering are busy on the roll out and while taxiing into position.
With the slider, if the landing is long ( HARDLY EVER WITH A BIDULE ) I could apply a little brake pressure if needed to shorten the landing. Once in position and waiting for the sailplane hookup we'll simply slide it all the way on to the "parking brake" position.

[lenb]

Some photo's provided by Scot S and posted in elsewhere regarding the nose wheel steering servo saver.

[lenb]

Some more ...

[gunny11]

Len, Did you or are you going to put the lock nut on the axle? Just noticed it's not on there.

[lenb]

Thats what they were for !!!!!

[gunny11]

Lol your toying with me again.

[eajbrian]

I got the parts from Dollar Hobbyz as a whole front steering unit, you get a lot of parts, more than you needed! http://www.dollarhobbyz.com/products...nt=10907321857