That looks good. It will be interesting to see how it works with the air pump. I’ve been playing with the pump power and on/off times, but I’ve only succeeded in making it work less well than it was before. Ah well, tomorrow is another day.
Regards Graham
Hi JB - seen you have not yet read my last message. You said you have 3 boats - which ones are you referring to ?
My Dad & I built dinghy's on our verandah - Mother was very easy going about some things - cant remember what order - normally 2 at a time. there was a Heron, Enterprise, GP14, and a Mermaid (built like a Mirror but pointy ended, gaff rigged). First was a "Feather" duckboat - 8' of sheer pleasure to a 10 year old. Tough boat - went over a drift (wading crossing instead of a bridge) and hit various rocks at times with very little damage. Last Dinghy we had (sold the rest) was the Mermaid - rotted under her cover at the club some 25 miles away as I was away in UK studying for two years. Brother in law promptly built a pram and used her sails & fittings including rudder, centreboard etc. Good times - but have not owned a full size boat for many years - my last one a 16' cathedral hulled Fisherman with an electric start 50hp Mercury "Thunderbolt" used on Kariba - not much convenient sailing water around Johannesburg where we lived while the kids were growing up - (needed to be there for a good job to pay the bills) - the bit that was convenient was totally overcrowded, even the model boat club had to move to a lower pond because of canoeists infringing on our section. My one steam boat actually sank a canoe leaving the occupant struggling in the water - but that's a long story
The sealed version should work, that’s effectively what I have. The oil tank has to be sealed else too much oil gets drawn into the coil and it floods. I have a filler screw with an o-ring seal on my oil tank to fill it. I don’t think the fan version you have drawn will work. The oil tank isn’t sealed with that one.
I can see why your old diecast box isn’t useable for this!
Graham
The coils I'm using are 1.8 ohm. They are designed to work with a single LiPo battery, i.e. nominal 3.7v. I have been running mine on 3.7v - 4V. It gets slightly warm, but nothing to worry about. I'm powering it from 8v through a buck converter which has an adjustable output and is claimed to be 98% efficient dropping the volts from 8v to 3.7 - 4v. You can just see the converter in the top righthand corner of the photos. When combined with the pump, it draws about 0.9A from the 8v supply when the coil is operating at 3.7v and 1.0A with the coil at 4.0V. The pump is running on the 8V supply. The nice thing about the buck converter (from ebay) is that it halves the output voltage and halves the input current. So 8v 0.9A input equates to 3.7V 2A output to the coil (approx). I'm looking to power this off the receiver/aux battery in the Crash Tender which is a 2S LiPo. I got 5 coils for less than £5 so they are cheap here. Apparently they need to be replaced in an e-cig at regular intervals. I'm still using the original one, despite it having a lot of mistreatment.
Agreed, not something to run for extended periods. I don't know what the threads on the coil are, certainly very fine. That's why I bought the complete tank, etc as it is ready threaded for the coil and makes it really easy to replace.
The plumbing isn't quite as you drew it. See the revised drawing. I'm not using the 'tube in tube' outlet. I found it works better with a simple T connection as shown. Bubbling the smoke through the water gives a more realistic effect (IMHO). The smoke isn't absorbed, but I think that is due to the higher air pressur from using the air pump rather than a fan. The only problem with the plumbing is the risk of backflow of water into the smoker. I've had a couple of issues with this. I've just tried adding a non return valve to the smoke pipe just before the 'T', but it didn't work too well as the smoker doesn't like any back pressure. I've now moved the non return valve to between the pump and smoker and I think that will fix the issue. As the pipework and smoker are sealed from the non return valve to the water T, there shouldn't be any backflow. Not had time to test it properly, and I'm away for a couple of days so it will be the end of the week before I get chance. Updated the electronics, see the second picture. Now much simpler and with better performance - also smaller than a matchbox!
I plan simply to drive this on a 'Y' lead on the throttle channel, (and possibly a syncronised sound generator 🤣 - but that is something for another day).
Yes, we could probably make and sell these for a few £/$. However I have recent experience of making and selling electronic devices on line. Made over 300, including etching circuit boards, etc. Lots of demand but not worth all the time and effort. Stopped making them a year ago, but I still get enquiries.
The e-cig is listed on ebay.uk as 'H2 Atomizers Clearomizers E Cigarette Oil Vape Pen Juice Wickless Refill Tanks'. Don't know if you have anything similar in NZ.
Attached is a photo of the motor control electronics. Need to simplify this!
I tried lots of different setups including pulsing the water with a solenoid, pulsing the airflow with a solenoid, pulsing them both, tube in tube mixing. They all sort of worked, but it was all getting too complicated, and too bulky. So I decided to go back to the start and use as few components as possible.
The set up now is the air pump feeding into the smoker. The smoke outlet tube is then connected with a simple T to the water tube. The water runs continually, using an aquarium pump in my test rig. I’m hoping that the normal flow from the water scoop on the model will be OK, or I might have to use the fire monitor pump. The speed of the air pump is pulsed with a bunch of electronics. It is pulsed from slow to fast and back, not simply on/off. The change from slow to fast is ramped, not instant, as with it instant, there was lots of water spurting from the exhaust. The pulse rate is varied by the throttle setting. I still have some work to do on the electronics, to improve its operation, and make it smaller.
The e-cig I bought included the heater and the tank/mouthpiece and cost £1.75 from eBay including postage. I’ll find some details and send them to you.
Local scientist is predicting end of world in 10 years - hastily contradicted by French one who says 30 years . Something to do with Global Warming and what killed the Dinosaurs...........
Don't think I will be around to see in any event , COPD catching up with me now after too many years supporting the Rhodesian tobacco industry and demolishing/renovating houses without using a dust mask.
Opening new shop on Monday - so will have time to get on with unfinished boats whilst sitting there - usually quiet midweeks. Time off will be running the laser from our garage.......
Getting to be a bit of a pain at 74...........
Regards
Peter G
How This Then JB
"As part of its commitment to support Lead2030, Mondi formulated a challenge related to SDG 12 ‘Responsible Consumption and Production’ to address the issue of waste. Mondi selected Kenyan company Eco Blocks and Tiles as the challenge winner and provided them with R733,470 ($50,000) in financial investment, alongside 12 months of business coaching, to equip the company with the expertise to grow and scale the business.
Eco Blocks and Tiles, co-founded by Hope Wakio Mwanake and Kevin Mureithi, turns plastic waste into affordable roof tiles for homes. The business positively contributes to SDG12 by creating value out of plastic waste. The One Young World annual summit will take place this week in London, and Wakio Mwanake as well as colleagues from Mondi will be attending."
little bit late for the world though
Regards
Peter G
You should be able to adjust the pipes I sent to look more like your diagram with the central pipe offset. The central smoke pipe is soft soldered into the bush at the end of the outer tube. The bush, and the water inlet pipe are silver soldered, so it shouldn’t be too difficult to melt the soft solder and reposition that tube, without upsetting the other joints.
Here are a couple of photos. I have made an acrylic connector to fix in the end of the e-cig which makes connecting to the heating coil easier, and also connects the airflow from the pump. The e-cig only has a capacity of 2ml of smoke fluid, which doesn't last very long so I've added an extra reservoir which holds lots (not measured it yet) and it runs for ages. I've had it running on/off for most of the day and it has used only half the fluid. The whole thing can be unscrewed to replace the coil if it fails. Touch wood, it hasn't done yet.
The second photo is self explanatory! It copes well with a length of silicone tube on the e-cig outlet (originally the mouthpiece). I have about 2 ft of tube connected so I can get the smoke out of the workshop. I think the difference here is using an airpump rather than a fan.
I'm not going to publish any of this yet, as I need to finish off the crash tender fire monitor saga (another installment on that coming soon). Then I'll look to publish the smoke generator as part of that blog as I install it in the tender.
