I don't have an example for the DX8 but have used the Sullivan and it should work fine. If I can I will try to set it up and post screen shots.
I think the simplest thing to do is plug the pump into the gear channel. Create a mix on Mix1 for throttle to gear. Set the SW to Gear. Change the numbers to that the pump is always off with the Gear switch in position 0, no mater where the throttle is. That way you can turn it on and off with the Gear switch. You can see on the monitor on the mix screen where the output of the Gear channel is going.

Gear switch position 0 value -100
Gear switch position 1 values +41 to +100 with the throttle 50% to 100% (for example)

The mixes are not all that easy on the DX8 but you should be able to get it to work. Once working you could change the switch and use another channel.

You want to make sure you are not delivering too much smoke. Too much will not burn and will leave your plane a slimy mess with the covering pealing off.

Here is the setup values from the Sullivan instructions.
ATV output from Receiver:
-140% to -15%: this is the desired signal when the switch is in the "off" position. The Skywriter must see a signal in this range for at least 5 seconds before it will activate.
0% to +40%: the Skywriter will not come on but this will not over-ride the fail-safe, a negative signal is required for this (see above).
+41% to +100%: This is the proportional band of the control. The motor will turn it's slowest at +41% and will be turning full speed based on the battery it has at 100%.
+101% to +140%: This range is interpreted the same as +100%. The skywriter will still run at full speed

You guys forced me to take drastic measures and I got out the manual. Don't worry, I'll be OK.
I have it working, by sound right now anyway. I ran it with the pump yesterday but I think the pump was wide open. Around 4 a this morning (I got u thinking about this) I redid the mix and now the pump goes off at near idle and comes on when the throttle is advanced. I can't actually hear a gradual change in pump speed but I can raise the top number in the mix and make it speed up. I am pressed for time as I have fun fly on Saturday morning and have two other planes to get ready so I am going to fly the Extra with the pump as is. Now that I know the top number in the mix more or less controls the pump I can speed it up if the smoke is not "big" enough, something I kind of doubt considering yesterday, see the photo below. Warning the photo is way bigger than I thought my phone took....


Once I get the plane in the air and try the smoke at speed I will report back with my "setup" to see if it works for others or if we can tweak it further depending on performance.

I still can't get the mix (DX8) to do anything but make tons of smoke or nothing. I've never done mixes because I like to do all that with my thumbs. I really am dense or something with mixes, which one comes first on the screen? So far I haven't come across one that has a curve on the smoke channel. I know this is going to be simple when I figure it out but the world is lacking some decent explanations of mixing!

If all you want to do is turn down the smoke rate with switch on, go to menu by clicking the roller, go to servo setup and click the roller, then you are going to adjust the travel of the gear switch so leave travel alone and go down and it says throttle, click on that and rotate the roller until you get to gear, then flip the switch to the desired position that turns on the smoke and scroll the box down to where both say 100% and the box will be circling the one you want to adjust, click on that and the box starts flashing, scroll the thumb wheel and you can adjust the percentage down to where you desire. Test it and if it is still too much, repeat until you get the correct amount of smoke. If you wish to tie it to the throttle then you will have to mix the gear channel to the throttle channel and give it the correct curve. I can walk you through that if you wish.
Dennis

Thanks, Dennis, I'll give that a shot in a bit. I should be able to fly it later today. If I can just get the pump turned down, that might be enough. Stay tuned!

OK, -played with this in the garage and I can make the pump slow down, but by changing the right number though the left number has the flashing square around it. The pump turns on and off with the gear switch fine and in the right position (switch towards me for on). I am going to leave it like that for now as I hope to fly today and can see how it works in flight not just listening to the motor in the garage.


Thanks again! We are making progress.

Sounds like you got it. Good luck and happy flying!
Dennis

its not mixed but I think we got the pump running slower. It looks like the same amount of smoke but the plane was cleaner at the end of the day. I did manage to pull of a two-rotation torque roll hanging on the prop and the plane disappeared so I gassed it and hoped it came out the top of the cloud, which it did.
Now I have to alcohol the hell out of the fuse and try to get the covering nailed back down.
My biggest problem now is getting the smoke oil into the plane. I have been using like the DuBro hand crank gas pump and it works some then just makes lots of bubbles. Is there a secret pump hat works good with smoke oil?

I purchased an electric pump that pums gas and smoke oil from hobbyking for 27.00 a couple years back, makes life much easier.

Dennis

Sub-ed

Originally Posted by stevehookem

So I go into the gear menu and lower the travel's high value end point to lessen the flow?

This is what I would do.

Step 1: Disable the gear switch so that it doesn't control the gear channel.
Step 2: Create a mix of Gear to Gear, Values -100,-100, enabled by the gear switch being set to the inactive position. This will disable the smoke pump when the switch is off.
Step 3: Create a second mix of Throttle to Gear. A point mix if possible (I haven't had a DX8 for a few years now). Enabled by the gear switch being set to the active position.

Adjust the values for the Throttle to Gear mix to give you the flow rate desired.

Hope this helps.

Wayne

I found the best way to test it is use a can on the bench, full flow at full throttle and just dripping at half throttle, or you can drown out the plug and have a dead stick. I use DX8 the gear switch to turn on and off and another mix to regulate flow mixed with throttle. works perfect

And the good part about bench testing you don"t waste smoke oil, and you can see you changes in the mix