Bidule 111 v2.0

[stevekremer]

Jim,

Were you at the Salem Turkey Tow at 4:26 pm to post pictures?

Then back at your workshop at 5:25 pm to post pictures of your Bidule build?

What mode of transportation are you using? I am impressed!

Steve K

[JimD]

Hi Steve, I used the remote photography app on my iPhone.

[lenb]

He rode in on his Bidule 170

[stevekremer]

I have to download that App

Steve K

[JimD]

The Bidule 111 nose gear uses M5 socket head bolts for all the pivot points and for the wheel axle.

As experience has shown, when a threaded section of a bolt is used as a pivot point, the threads act like a file over time causing wear to the holes in the parts that pivot around these bolts. None of the M5 bolts in the nose gear had smooth shanks long enough to go fully through the parts of their respective pivot areas.

Using a bolt that is not fully threaded can offset this problem provided you can find ones that have a smooth shank the length needed.

After careful measurements were made and much time was spent looking at the specification diagrams on McMaster Carr's website, we ended up ordering every M5 alloy socket head bolt they have starting with M5x30mm and going up through M5x100, so here is what we discovered.

M5x30mm bolt has just enough smooth (unthreaded) section to extend through the hinge slot before needing to thread into the other side of this three part hinge at the top of the shock tube.

M5x70mm bolt has the perfect length of unthreaded section to go fully through the pivot and both of the bushings in the side plates of the wheel mounts.

M5x80mm bolts have same perfect length to go through both bushings in each of the side plates for the lower shock mount and the wheel axle.

BTW, 5mm is approximately 3/16" (just slightly oversize) and the 5" DuBro wheel we are using comes with a 3/16" hole in it, so this M5x80mm bolt makes a perfect smooth axle for the wheel to rotate on.

The stock bolts can be seen here beside their replacements. The excess length of each of these bolts will need to be cut off to make a neat installation.

[JimD]

From prior experience with my Bidule 170 nose gear, we took all of the bolts out of the tiller arm and re-assembled using Blue Zap Z-42 Thread Locker. Then we cut the new bolts pivot and axle bolts to length. The upper shock mount is screwed to the gear leg with a 3mm bolt, we added a lock washer and re-installed with thread locker, plus changed out the pivot bolt with the new bolt cut to length.



The bottom pivot mount is attached to the gear leg with a single M3x6mm bolt. We changed to a longer M3x9mm bolt and added a lock washer.



The wheel assembly pivot bolt was cut to length and re-assembled using a touch of anti-seize lubricant.



Then the axle and lower shock bolts were cut to length and the parts re-assembled.Now we have a full width smooth axle for the 5" DuBro front wheel.

[eajbrian]

Jim,
photos not visible?

Brian

[JimD]

Brian, check your security settings, the photos are in Photobucket with links to this forum. Possibly your security settings are blocking content linked from another source.

[eajbrian]

OK, I think I know why! firewall at work.

[eajbrian]

I can see some of the photos in the older post, like the ones that Asher posted.

[JimD]

Front line production tow planes do a LOT of takeoffs and landings, often in less than ideal wind conditions, so a sturdy landing gear is essential. The Bidule is a great airplane, but even a well designed plane can use a little extra help when it is going to be subjected to the abuse of life as a tow plane!

The composite main landing gear is fabulous, long, tall, and strong...the weakest point is the gear plate mount in the fuselage bottom. We decided to add some plywood cross pieces and flooring in to strengthen this gear mount just like we did in the Bidule 170. Our 170 logged 60 hours of towing this season with zero gear issues!

Here is the stock gear plate area in the fuselage.



Using some scrap thin cardboard to make patterns, we cut 1/8" aircraft plywood cross braces and then some flooring.



These were glued in with epoxy and #403 microfiber mixture and short pieces of stick were cut to hold the rear cross brace tightly against the gear plate. The floor plate in front of the front cross brace acts to hold that piece tightly in place.



Next step was to add plywood floor doubler to the bay in front of the wing tube. this is the area where the canister mounts will be attached, so the floor here needs to be strong.

​​​​​​​

[JimD]

We decided to open up this section to give access to the floor area by cutting out a piece of the tank mount (didn't intend to mount the tank here anyway).



This piece will be replaced with other structure,



Tower 6" x 12" plywood is the perfect width to fit the width of the floor. After cutting to length,we cut our piece in half to assist installation. Then we moved on to backing up the framework with balsa stick.



The 5" DuBro front wheel arrived in the mail today, so we mounted it on the nose gear. The 3/16" hole needed to be drilled out to 13/64" for a perfect fit on the 6 mm axle. 1/4" wide by 1/2" diameter Nylon spacers for #10 bolts were just the right size needed to finish the installation. I have used a similar method for mounting the nose wheel on my Bidule 170, just larger Nylon spacers.



It takes two spacers per side of the wheel and when the axle bolt is secured with a nylon insert lock nut, the front wheel runs very true with no wobble. Nice clean and neat wheel assembly.

[JimD]

Now for a test fit of the nose gear steering system. As stated earlier, we used a DuBro 6-32 Monster Ball Link with a 6-32 stud threaded into the supplied steering rod to make the attachment to the tiller arm.



Inside, the stock servo tray and servo saver device were used. We attached the mechanism to a large servo output arm disc so the bottom of the servo saver block would be supported on this disc. We also used a 4-40 bolt with a smooth shaft to attach the device to the arm so the pivot is not riding on the threads of a bolt. Seems to work well when we apply pressure left and right against the nose wheel.

[JimD]

Time to do a test fit of the engine...the shiny new DA-100 bolted right on just as planned!!

[French1]

Look good,

I am waiting patiently the next step, or one of, Header pipes...

I can use some extra motivation to get mine done!!!

Stéphane

[JimD]

And I am waiting on parts from Chief Aircraft to install them. I ordered the KS Comfort mounts for the canisters and I have the parts to build the headers, just need the final measurements to set the amount of drop needed before cutting and welding parts together.

[JimD]

Looking at the throttle and choke levers, it is apparent that the stock arms are not going to work well. P-S-P Manufacturing makes throttle and choke arms for the Walbro carburetor that will be perfect! Got them on order now.



Moving on to the exhaust system, We will be using MTW 75 rear dump canister mufflers and have KS Comfort mounts on order to mount them to the bottom of the fuselage. Once we have those and can determine the exact length needed for the header pipes, we can get those fabricated.

[AureleAlain]

Hi Jim,

I'm doing some final touchups to finish off my Minimoa, then on to build my Bidule 55 then the 111.

Can you tell me what is the source for the header parts shown above? I'm going to need a similar header.

With Thanks
Aurele Alain
Ottawa, Ontario

[JimD]

Parts came, so we finished out the horizontal stabilizer elevator control rods. In order to make assembly more efficient, Sullivan 4-40 Ball Connectors are being used.These enable a quick connect/disconnect between the control rods and the elevator servo arms..

Hangar 9 Titanium 4-40 Pro-Links were used for the flaps and ailerons, so we elected to use them on the elevators as well. The 4" rods were too short and the 4-1/2" were a slight bit too long. We used the Dremel tool cutoff disc to shorten the ball link end of the rod by 1/8". This allowed the rod to be fully threaded into the link housing. The Hitec HS-5645MG servos come with a metal output arm. We drilled out the outer most hole and then used a 4-40 tap to thread the hole. The threaded ball stub that comes with the Sullivan unit was screwed into this threaded hole and than a nylon lock nut was used to further secure it to the servo arm.



The opposite end of the Pro-Link was fully threaded into the nylon ball link for a control rod that is just exactly the right length.

[JimD]

The KS Comfort Mounts arrived and we discovered a problem, the MTW 75H canisters are too small in diameter for the KS Comfort Mounts to tighten down around for a snug fit.One way to fix this is to put pieces of silicon tubing over the straps of the KS Comfort Mounts, but this is not the best looking result.

See the post here for the specification comparison between KS and MTW canisters.

We decided to find a new home for the MTW 75H canisters and bought a set of the KS 86 canisters to use instead. The KS Comfort Mounts make a nice clear installation the allows good cooling and light weight.



The previously mentioned issue with the carburetor throttle and choke arms was the next thing we addressed by ordering the PSP Walbro Throttle and Choke arms. This will allow us to have the throttle and choke pushrods on the same side of the engine. If we could have place the choke arm on the opposite side, we would have been okay, but the steering tiller arm is in the way for that.

The clearance is close and a bit of finesse is needed to get them spaced so they don't hit each other.



Throttle is the top lever and choke is the bottom lever.

[JimD]

Another one of my favorite things is gluing on canopies (actually, I dread doing this). We have found that Zap Goo or hardware store Shoe Goo is the best for this task. Problem is that it will skin over quickly and ooze out in all the wrong places if you are too slow or too clumsy applying it. The Bidule canopy is very large and we found that gluing it on in two stages works best in order to avoid the aforementioned problems

First step was to remove the covering that will be under the canopy's painted frame.



Masking tape was applied to the fuselage so we would not end up with the canopy glued to something we didn't want.



Glue was applied to the front and rear of canopy and then it was taped in place while the glue dried.



Allowing overnight for the glue to set, the canopy and frame were removed from the fuselage and the sides were glued down and tape used to hold the sides tight to the frame.



The Bidule has a fiberglass fairing that gets glued to the horizontal stabilizer. Again, the covering was removed under this piece and the bottom of the fiberglass part was trimmed and sanded so that it would lie flat on the stabilizer with no gaps under it. Here we used epoxy mixed with the #403 microfiber filler material.