RC Tanks Discuss all aspects of rc tank building and driving here!

tamiya cannon elevation .....

Reply

Old 03-19-2018, 05:38 PM
  #1  
da Rock
Senior Member
Thread Starter
 
Join Date: Oct 2005
Location: Near Pfafftown NC
Posts: 11,491
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default tamiya cannon elevation .....

First tank is Tamiya PzIV. Most fun I've had in the last few years assembling it.
I wanted to have the cannon's elevation control on the TX's throttle and use the ratchet to help me control elevation with the clicks. Setup for all the controls worked out great. I think.

What I'm opening this thread about is how the gun works. I adjusted the gun to be parallel to the ground when the TX throttle stick is centered. Giving it more throttle (pushing the stick UP) aims down. Moving the throttle stick down (less throttle for a/c) increases the guns elevation or aims higher.

The way it presently works is like an on/off switch that simply runs the barrel up or down as long as the stick is displaced from center enough to start it moving.
In practice....... until the stick is given more than 3 clicks up or 3 clicks down, nothing happens. As soon as the stick is 4 clicks either up or down, the barrel starts moving. It moves until the stick is brought back to that neutral zone. It's pretty much impossible for my old eyes to tell the barrel is moving or not unless the tank is fairly close. When it's more than halfway across the width of the battlefield at the tank museum, that barrel's elevation is a mystery.

Is it working the way Tamiya wants it to work?
Is there a way to setup my Spektrum TX to match the barrel displacement to the stick displacement (and have it indexed to the TX stick)? in other words, the way I want it to work?

tia
da Rock is offline  
Reply With Quote
Old 03-19-2018, 10:55 PM
  #2  
Rad_Schuhart
 
Join Date: Jul 2015
Location: Graz, Austria.
Posts: 317
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Im a bit lost and I dont really understand what are you doing and what you want to do...

You are having the barrel elevation and depression in the same stick as the throttle? If so, why? You have two sticks, why not to use one stick for turret functions and the other one for driving?
Rad_Schuhart is offline  
Reply With Quote
Old 03-20-2018, 05:11 AM
  #3  
Shorty54
 
Join Date: Feb 2015
Location: Alexandria, Minnesota, USA
Posts: 397
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

It sounds like he doesn't have dual centering sticks. He is using the throttle stick (left stick) which is not self centering but on a ratchet.
He wants the barrel to match his stick position. So if the stick is in the center of the gimble, his barrel is level, with the ground.
If he moves the stick up 3 clicks the barrel moves down a small amount and stops and stays. He wants to use is radio as a guide to his
barrel position according to his left stick. if he cant make out his barrel because his tank is too far away, he can look at his elevation (throttle)
stick and judge roughly off of that. Stick full up, barrel full down, center stick barrel level, stick full down barrel full up.

I think its a neat idea, and makes sense. I just have no clue how you make it work.

Shad
Shorty54 is offline  
Reply With Quote
Old 03-20-2018, 06:09 AM
  #4  
Jeff489
Senior Member
My Feedback: (12)
 
Join Date: Jul 2005
Posts: 1,246
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Is it working the way Tamiya wants it to work?
Yes, that's the way it's supposed to work.

I understand you want incremental control of the cannon, but the problem you run into is that Tamiya electronics use that channel of their electronics to fire the main cannon and MG using an exponential signal (triggered by a rapid full deflection of the stick on that channel).

The only way I know it could work like you want, would be to put the cannon elevation/depression on an extra channel that has a knob control on the transmitter(giving incremental control), but then you'd have a new problem of how to fire the cannon/mg, since you won't be getting any exponential signal easily.

You could remedy that by mixing another channel (i.e. program another channel on a switch to use the cannon channel as a slave, and get the instant full deflection to fire the MG or cannon) with the channel used with the know. Use the new channel as master, and slave the knob channel to it. A switched channel gives 100% (or more if you adjust your travel stops) deflection instantly. An open channel with a 3 position switch would be ideal.

Not sure what radio equipment you are using, but I use a Spektrum DX9 on some of my tanks, and I know it would do this. I use a switch to run my cannon and MG on it, and use a stick to elevate or depress. Whatever you do, don't try shunting the the pot on the elevation stick, as it will fry a newer Spektrum.

As to the self centering stick issue, it would be a good idea to make both sticks self centering. Older Spektrums require a new cam and spring (you'll need to send it in to Horizon for that, as they don't sell parts), or on Gen 2 Spektrum radios (Gen 2 radios have that sexy English accented female voice that tells you "bind complete", etc), simply adjust using the screws under the stick on grip pads.

Last edited by Jeff489; 03-20-2018 at 06:17 AM.
Jeff489 is offline  
Reply With Quote
Old 03-20-2018, 06:57 AM
  #5  
da Rock
Senior Member
Thread Starter
 
Join Date: Oct 2005
Location: Near Pfafftown NC
Posts: 11,491
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Originally Posted by Jeff489 View Post
Yes, that's the way it's supposed to work.

I understand you want incremental control of the cannon, but the problem you run into is that Tamiya electronics use that channel of their electronics to fire the main cannon and MG using an exponential signal (triggered by a rapid full deflection of the stick on that channel).

The only way I know it could work like you want, would be to put the cannon elevation/depression on an extra channel that has a knob control on the transmitter(giving incremental control), but then you'd have a new problem of how to fire the cannon/mg, since you won't be getting any exponential signal easily.

You could remedy that by mixing another channel (i.e. program another channel on a switch to use the cannon channel as a slave, and get the instant full deflection to fire the MG or cannon) with the channel used with the know. Use the new channel as master, and slave the knob channel to it. A switched channel gives 100% (or more if you adjust your travel stops) deflection instantly. An open channel with a 3 position switch would be ideal.

Not sure what radio equipment you are using, but I use a Spektrum DX9 on some of my tanks, and I know it would do this. I use a switch to run my cannon and MG on it, and use a stick to elevate or depress. Whatever you do, don't try shunting the the pot on the elevation stick, as it will fry a newer Spektrum.

As to the self centering stick issue, it would be a good idea to make both sticks self centering. Older Spektrums require a new cam and spring (you'll need to send it in to Horizon for that, as they don't sell parts), or on Gen 2 Spektrum radios (Gen 2 radios have that sexy English accented female voice that tells you "bind complete", etc), simply adjust using the screws under the stick on grip pads.
Thanks for the help. I figured it was working the way Tamiya designed it but wasn't sure.
I owe you so...... I'm using a DX8 and use the 'kill switch' solution to fire the cannon. That solution meshes with Spektrum's use of the Bind (switch "I") button to pulse the throttle signal. Takes a minute to setup and works like a trigger.

The radio is a G2, but was one of the first and requires a new cam/spring and I was figuring to work around that. Hoping the elevation design would cooperate, but it doesn't. I've got a couple of parts Spektrums to pull a cam from. Self-centering works great, it was just the TX I wanted to use not having the cam that bumped me toward my first setup. Thanks again.
da Rock is offline  
Reply With Quote
Old 03-20-2018, 07:01 AM
  #6  
da Rock
Senior Member
Thread Starter
 
Join Date: Oct 2005
Location: Near Pfafftown NC
Posts: 11,491
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Originally Posted by Rad_Schuhart View Post
Im a bit lost and I dont really understand what are you doing and what you want to do...

You are having the barrel elevation and depression in the same stick as the throttle? If so, why? You have two sticks, why not to use one stick for turret functions and the other one for driving?
Thanks for helping. I do have the turret and gun elevation on the left stick. L-R moves the turret, U-D controls the gun elevation. I fire the gun with the Bind button. Spektrums are very flexible.

The answers I got have given me the info I needed. thanks again
da Rock is offline  
Reply With Quote
Old 03-20-2018, 07:03 AM
  #7  
da Rock
Senior Member
Thread Starter
 
Join Date: Oct 2005
Location: Near Pfafftown NC
Posts: 11,491
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Originally Posted by Shorty54 View Post
It sounds like he doesn't have dual centering sticks. He is using the throttle stick (left stick) which is not self centering but on a ratchet.
He wants the barrel to match his stick position. So if the stick is in the center of the gimble, his barrel is level, with the ground.
If he moves the stick up 3 clicks the barrel moves down a small amount and stops and stays. He wants to use is radio as a guide to his
barrel position according to his left stick. if he cant make out his barrel because his tank is too far away, he can look at his elevation (throttle)
stick and judge roughly off of that. Stick full up, barrel full down, center stick barrel level, stick full down barrel full up.

I think its a neat idea, and makes sense. I just have no clue how you make it work.

Shad
Thanks Shad......
You spot on.
I think I got a couple of ways to get'er done. Thanks to all 3 of you guys. I owe y'all a drink. I'll email it, OK
da Rock is offline  
Reply With Quote

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy