A fan powered smoke unit (modified Heng Long) tried in the HSL. Not particularly good but it's output is reasonably scale(ish). As the fan (12v comp snail fan) just blows into the back of the smoke box without any positive connection, a fair bit of smoke escapes into the engine bay. The fan is hooked up to run with the cooling pump and is left on while running after the smoke (on off remote from the rotary switch) is turned off, and blows the residual smoke from the engine bay out the exhausts.

There are also the 2 small air pumps plumbed into the exhaust outlets via venturi pipe inserts, to blow the water out of the exhausts, (just on the waterline) as any water stops the smoke coming out (surface tension holds it in the pipe). Once I find a decent high volume small quiet air pump, I can do away with these and the fan, which should make things a bit better.
I've ordered some small 12v 40W printer elements to try another smoker idea, but they will be a while coming. Smoke will only be on for startup so shouldn't be too much of a problem.

I've almost become water/vaporlogged/glycerogged with all these experiments, and the other night I actually set off the smoke detectors,- house smells like a glycerine factory for hours afterwards,- but my skin's getting really smooth😂😂😂😂
JB

This is the top of the line, premium, top grade, no expense spared, gold standard, fully reverse flowed liquid converter. Assembled by skilled Latvian craftsmen using quality hammers and pick axes, and working in the most modern up to date farm sheds. We at Smoke R&D, present the Smoker Model X - "A smoker for the discerning modeler" (said Botswana Model Monthly)
JB, Head Sherang, Smoke R&D.

Still waiting for a better air pump so thought I'd try whacking 2 pumps on and upping the voltage from 2 to 2.5V Works a lot better but smoke still a bit slow. If I blow gently into the air tube I get massive clouds of smoke (hence the need for a better pump) Sorry about the crappy vid,- camera lens has a cloudy spot and not so good inside.
JB

Managed to get a smoker fitted in the HSL and it works reasonably well. Would have used a small ESC to vary the smoke etc but have run out of channels on the 6ch TX (also room). Could use my 9X TX but would have to mod the elevator to a throttle (for twin set-up) I could use the TX to program smoke advance etc using the curve facility. Might do that later as I mainly use my Futaba 6ex and 9XR for my planes and hardly use the 9X, (even though it's a good radio).
JB

Trying air injection to break up the water flow. The air pumps I ordered finally arrived a week late but are too small to be of much use. I need a much bigger and faster volume of air to achieve what I want, which is for the water to almost be sprayed out in a mist. Might need to mod the water outlet by fitting fine tubes or stoppers around the inner smoke tube to build up a bit of back pressure, which might be another alternative
Unfortunately, as I've said before, you can't scale water, due partly to surface tension etc (why it either drips or runs out of a small pipe), so to make it fine you have to pressurize/vaporise it at the point of exit (ie garden sprayer) which is the hard part on a small scale. Lots of fun trying to perfect it though, and it keeps me out of trouble, and keeps the brain working - (although it's just asked for a pay rise due to all the work it's been doing lately!😂)

Tip,- if you run both videos at once you can see the difference between this and the last vid. It also breaks the smoke up.
JB

Just trying a few more things while waiting for more bits to arrive. This time using a small ESC for the smoke, and using CH 6 (rotary pot) on the TX. Water is adjustable with the voltage reg but could be hooked to the motor ESC as well, with a voltage reg used to set max flow. I'm just using the Heng long smoker box (modified) for this test.

😭Video of my San Reno running around with a Graupner Kitty II and a semi scratch built tug on Towne Lake, was visited by Wile E Coyote too!!

I know ...I can't help it...thought I would share some pics of my collection. I have been adding Dodgers, handrails etc and continue to do so as well as starting new builds. Enjoy

Using the e-cig element in the alloy box again but with the old smoker pump bored out and converted to a single outlet in line with the piston. Even makes a cool sound out the exhaust side!. Still waiting for my air pumps so just playing around in the mean time. Also trying glycerin and water 50/50 instead of baby oil. The pump doesn't shift much air ( slightly more blowing than sucking, - sort of pulsing back and forward) but if I blow down a tube I get clouds of smoke, I'll see what the air pumps do. Still only running on 2v.
JB

Made a few changes to the pulsing frequency/timing, and to the plumbing where the smoke is mixed with the water. Video shows the pulsing speeding up with throttle setting. Happy with this now, I can adjust the volume of smoke once it is installed in the boat. Probably will need less, but it is difficult to be sure as conditions on the lake are different to those in my workshop!

Graham93

This version of a smoker box uses an E-Cig element in an alloy electronics enclosure.I gave the lid and box a 7mm haircut on the mill to reduce the size, (now 50x50x26, - was 50x50x33) but it could still be 1/2 the width. haven't found a smaller alloy box yet but might come across one, (only really needs to be 35mmx35mmx25mm The element is mounted on a bracket screwed to the bottom of the box (the box being the resevoir and neg) and against the outlet tube, and the pos wire runs through the side (in silicone tube) to the element.

The box is packed with cotton wool which is surrounding the element and soaked in smoke fluid (in this case baby oil) but leaving a passage through the center for air flow. I'm waiting for a couple of air pumps to arrive but I've used the old smoker unit pump again to demo the smoke and pulsing, (makes good smoke rings too)😊

The element is capable of taking 4.5v, but I'm only using 2v for the test and it smokes quite well. The pump is running on 7v but can be varied from around 3v - 8v. The large tubes are to allow for later exhaust fitting (water or dry stack). Once I get the air pumps I'll be running this one with the water again. I've done this (like Grahams version to be able to easily replace the element as the Heng Long smokers, while working ok (but noisy) have non replaceable elements, so if you kill one, it's off to file 13 at the end of the bench😉😁

The pump actually works quite well and if you mount it on sponge rubber it is reasonably quiet and could still be useful in a boat with a bit of interior room.

These photos show the stern modified ready to fit up the twin jet units that will power and steer this vessel.

More photos in a week or so.