Make Willys head turn when steering

[Yoshisaur 282]

Many users have made the head of Willy move in their Wild Willy. I wanted to do the same in my build but was surprised I couldn't find a topic* describing the steps so I decided to document how I did it, and post it here.

What's needed:

- Willy (obviously )
- Mini servo
- 6mm wall plug
- Small screw
- Servo Y-connector (Not on picture, still awaiting delivery)

 

Take some narrow tape (or cut a narrow strip from wider tape) and use it to mark the middle of the bucket seat

Now get a wider piece of tape and make it 32mm wide. Next mark the middle of it, I used dots so I could easily align it.
Mark the area to cut away from the bucket seat as seen below.
7mm from the bottom, 10mm from the sides, the top is 22mm from the bottom.

Cut out the square, make sure to not make it wider than 12mm as you need the mini servo to fit tightly

Remove the mounting extensions from the servo. Take the plug and remove the protrusions, fit it on the mini servo and position the servo in the seat as shown below

Now drill the hole in Willys body to 7mm (I did this in several steps just to be cautious to not damage the body) and place it in the seat.
If needed wiggle the plug a bit to reposition the servo. Attach the servo to the receiver, test the servo and see if it moves without obstruction.

When the servo is in the right place, make a mark on the plug where Willy's 'neck' ends.
Carefully remove the body so the servo doesn't move and glue the servo to the seat.
Now drill a 6mm hole in Willy's head, again do this in small steps and be careful not to split the head in two.
If you had previously inserted the nut before glueing the two parts you can use Tamiya glue to soften the plastic and pull the nut out.

Now take the plug from the servo and put it in the hole you just drilled in Willy's head, use the mark to get the height right.
Important! Observe the direction the plug will extend in when inserting the plug, make sure you don't split the two parts of the head!
Now use the small screw to fasten the plug inside Willy's head.

Now you can place Willy's body back in his bucket seat and fit Willy's head by pushing the plug on the output shaft of the servo.
Last thing to do would be to add the Y-Connector to the steering servo and attach the 'moving head' servo to it.

That's basically it, I hope this is useful for anyone wanting to make Willy's head turn when steering!

* It could be a guide was posted earlier, but I was not able to find it. If so, sorry for the double post

[Gebbly 760]

Thats a great guide, thanks @Yoshisaur so clearly explained I think even I could attempt it.

Is the Y connector used to split the signal going from ESC to servo so that the same signal is instead going to the 2 servos? any chance of a picture showing how the wires all end up getting connected together?

I have seen some other people achieve a rotating head and its interesting to see the different approaches people take. I think I remember seeing one youtuber who created a mechanical linkage between his steering and the head. It meant it didnt need the 2nd servo but instead there was some tricky wiring. I think that was in a King Cab which had plenty of space under the body.

[Willy iine 18823]

Very cool mod @Yoshisaur.   

@nicherotors did something like that in the past and I kept notes somewhere on how to do it using his 3D printed parts.     

I'm more a M38 guy restoring to original specs so did not do this, but M151 is a good candidate for sure since anything goes!  

[Busdriver 6270]

You connect the single end to the steering channel of your receiver and then the two you connect to the steering servo and the head servo. That means when you turn the steering the signal goes to both the steering and the head movement. You  may have to play around with the positioning of the servo as the head may turn left and the steering right!!!

[WillyChang 1816]

3 hours ago, Busdriver said:

That means when you turn the steering the signal goes to both the steering and the head movement. You  may have to play around with the positioning of the servo as the head may turn left and the steering right!!!

You’ll usually have to change either servo to a different brand... certain brands run one way vs signal others opposite. 
 

Or if you use a >2CH fancy computer radio, you can ditch the Y-lead and setup “mixing” to an available aux channel eg CH3. At really basic setting it can be straight mirroring or you can set %:% and reversing if needed. 

[nicherotors 321]

Thanks for sharing @Yoshisaur - I’ve found it a lot of fun for folks young and old to see Willys head animated. 

Looks like I used the same servo as you - only difference was that I decided to mount the servo inside the chest cavity using a 3d printed bracket (@Willy iine has a great memory) - as illustrated here: 

I liked the concept so much that on subsequent projects, namely the Wheeler and the Bullhead, we designed a cutout to accommodate the space for the servo to avoid and cutting.

After fitting bearings and dampers it’s always the next thing I upgrade on a Willy based project. 

[Yoshisaur 282]

Thanks for posting that link @nicherotors 

Effectively it’s the same method, but with the 3D printed part it’s easier to position the servo and you don’t have to worry about the exact size and position of the cutout in the bucket seat.

I love those wheels in that topic! I haven’t read all details in that topic yet, but I’m curious to find out if it’s in some way possible to mount these on a Wild Willy 2. I’ll probably post a follow up question to that in your topic.

 

Edit: Funny thing, I've just read the entire topic, I've also painted the rolbar using the black rubber, same as the front windshield rubber.

[Dan1891 210]

Is it possible to use a very small servo instead, so you can put the servo entirely in Willys body?

I found this one, it says its 16*13.5*6 mm.

Micro-Servo Sol Expert S18JST | Conrad Electronic

[Yoshisaur 282]

I'd say that would definitely be possible, only thing to figure out, is how to mount it and how to attach Willy's head, but that's the fun part right  

FYI, the servo I use is ~32*23*12 mm.

[Mokei Kagaku 2909]

I don't know how it's with digital servos, but if the servo is normal, changing the direction is possible by swapping the motor wires and the left and right wires(the one in the middle stays unchanged) on the potentiometer. Used to do it quite frequently when running two servos on MT's with 4WS.

[nicherotors 321]

I use the HiTec HS-55 and just checked the dimensions:  23 x 12 x 24mm

They work really well. To mount the head I use two 3x6x2.5 flanged bearings.

The silicon fuel tube acts like a universal joint which is forgiving if alignment is a bit out.

Hopefully this pic of the Wheeler driver also helps. 

Obviously a number of different ways of doing it - all a lot of fun given the driver is so prominent on this model. 

[Dan1891 210]

14 minutes ago, nicherotors said:

I use the HiTec HS-55 and just checked the dimensions:  23 x 12 x 24mm

They work really well. To mount the head I use two 3x6x2.5 flanged bearings.

The silicon fuel tube acts like a universal joint which is forgiving if alignment is a bit out.

Hopefully this pic of the Wheeler driver also helps. 

Obviously a number of different ways of doing it - all a lot of fun given the driver is so prominent on this model. 

Nice!

But thats only the torso Willy, not the full body, or?

[nicherotors 321]

Hi @Dan1891, same concept for both - but because the shape of the Willy chest cavities is slightly different we designed a different servo mount for each so that the bearings sit flush and are in line for the serrated cap head to pass through.