Bachmann Tornado wheel chuff syncro

[creilly81]

Hi all,

I've recently had my Bachmann Tornado DCC sound converted by a certain retailer. I was tweaking the CV settings for a good 2 hours yesterday for the correct wheel to chuff revolution, but cannot get it accurate

I checked all relevant CV settings before i made any changes as i wanted to know the defaults if any problem occurred. 
My understanding is, with the Loksound V4 CV57 and CV58 control the wheel revolution / chuff syncro, however also amending CV2 which is the start voltage can throw all previous settings out if this is changed afterwards.
As standard CV2 was set to 6 which is far too high meaning the loco wouldn't move off as slow as i'd like.

I changed this down to 1 initially, but had no luck in the fine tuning CV57 and CV58 into something i deem acceptable. I chnaged CV2 to 2 and looked again at CV57 and CV58, and although better, i just cannot get an accurate represntation of the correct chuff to wheel syncro from a standing start to mid speed. Sometimes it appears in time, but then loses it when either speeded up or slowed down. Currently with CV2 set to 2 i have CV57 set to 35 and CV58 set to 18. However the jump in 1 value either way with CV57 and CV58 are too big alteration and it throws the timing completely out.
Amending CV2 to a higher value does appear to reduce the change in sound chuffs much less, meaning a more refined adjustment can be made, however setting the value of CV2 too high and the loco doesn't start as slow as is required.

Is there anything i've missed in these tweaks?

I've also amended CV54 and 55 slightly, to get the running of the loco smooth, but i sorted all the running issues out before making what i thought were the final changes to synchronise the chuff and wheel revs.

Can anyone help?

[creilly81]

 

On our A4 model which seems to be similar to Tornado (5 pole motor, not the railroad range) we set

 

Default values: CV2 = 1  -> CV 57 = 244, CV 58 = 126, CV 249 = 9

Basic values if CV 2 = 2  -> CV 57 = 122, CV 58 = 36, CV 249 = 18

Basic values If CV 2 = 3  -> CV 57 = 76, CV 58 = 20, CV 249 = 18

 

Maybe this is helpful for your tests.

 

Saluti

Locoman

 

Hi Locoman,

 

That's perfect thank you so much for your help. I'll try those later and see how i get on.

 

Can i ask, does it differ from sound file to sound file in terms of how they are programmed into the decoder by the retailer, as to how the decoder reacts to the adjustments?

 

It's a shame you don't do a sound file for A1 in question - because you were the first place i checked!!   

[wiggy1]

There are other factors involved with the chuff rate.

If the above from Locoman does not work or you are still having problems send me a PM and I'll go through a few things with you.

Have you contacted the supplier that converted it for you as they should have set it more or less correctly.

I know every loco can be different weather new and run in or old and loose but it should be some where close if they have do the job right.

 

Wiggy.

[creilly81]

Thank you!

 

Chuff rate also depends on the speed curve which can be different by retailer so tweaking might be necessary.

Also CV2 and CV5 are important, the latter is set to 240 in our project.

 

Tornado project planned for July/August but need some recordings. Hope Tornado will go back into service soon.

 

Ci sentiamo

 

Locoman

 

Hi,

 

I did try your settings that you illustrated when CV2 is set to 2 - and it did form a good basis for which to start, but there is only a brief point in motion when the chuff matches correctly with wheel revolution, even when i've tried tweaking them further.

 

I hoping it will back soon too - as it's due to come down this way in May to Canterbury.... I'll keep a check on your website.

[34theletterbetweenB&D]

...Chuff rate also depends on the speed curve which can be different by retailer so tweaking might be necessary. Also CV2 and CV5 are important, the latter is set to 240 in our project...

 If the chuff rate depends on the decoder speed curve, then the motor must be a significant factor, as these can vary significantly in response to decoder output. By speed matching my locos across the whole speed curve, I see the range of variation between nominally identical motors.  My aim is a consistent linear response per speed step, and while most set ups are similar, the 'outlier' motors can have very different speed curve values: to compensate for the 'slow' motors that need plenty of current to start, and the 'fast' motors that start and spin up quickly on a breath of current.

 

If the motor in your Tornado has a response that is somewhat different from the usual run of motors, you might first want to adjust speed curve values to get a response similar to other locos.