Forum > Construction

1:25 scale Quarter-wheeler river Drogher

(1/11) > >>

Steven S:
This will be a build blog of a small quarter wheeler river drogher of my own design from information found on the internet.  The prototype would have been used to transport local goods on rivers and small lakes. Full size she would be 75 ft. long with a 22 ft. beam. 

 My 1:25 scale model will be 900x280 (35.4Ē by 10.9Ē), itís a little wide, but Iím a bit worried about stability.  The hull has a displacement of 7.5kg (16.5 pounds).

I will build a non functioning steam boiler, but the twin wheels will turn independently and be directly driven by two Cytron 12V, 150RPM geared motors.  It will use a Sabertooth electronic ďrobotĒ control module, controlled by my Spectrum Dx6 G2 transmitter.  I want to use 1 stick for throttle and the other for turning.

I was planning on having angled floats on the wheels as an experiment in steering the boat.  They would be angled to converge about 24 inches astern, but since they will be up against the sides of the boat and not protruding below or behind the hull I donít think that they would be effective.  Iíll start off by building a set of regular wheels. Any comments on the effectiveness of angled floats on a quarter wheeler or side wheeler would be welcome.

I am well along with the hull build and will start posting my progress shortly.  Itís fall here in Canada so this will be my winter project, ready for spring sailing next April.  Any comments on any of the build would be helpful as this is only my second boat.

https://www.robotshop.com/en/cytron-12v-150rpm-18oz-in-spur-gearmotor.html

https://www.robotshop.com/en/sabertooth-dual-12a-regenerative-motor-driver.html





DamienG:
Go for it Steven I look forward to your build.  :bravo :bravo :bravo

derekwarner_decoy:
Steven.......there are some builds here of similar sized pontoon style rear 1/4 wheelers, and also an article with a pair of wheels with angled float

The displacement of 6.5 kg is easiy increased via the flat bottom style...batteries/ballast up FWD

The only initial comment is these motors are listed as 150 RPM but with a no load rating as 103 RPM.......

With the electronic control, it could be worth considering a same frame size motor with ??185 RPM as with scaling....shaft speed is never a clear calculation with the SG of water being constant

The extra speed 'up your sleeve' may be beneficial  :whistle

Derek

Hankwilliams:
Very interesting and promising. With pleasure I will watch your build. I`ve built 2 steam driven sternwheelers - if there will rise any question you will get any  assistance with this blog.

Thomas

Steven S:
Gentlemen, thanks for your encouragement.  Derick, I used this motor in my first paddler build at the beginning of the Covid shutdown here in Canada.  I used a toothed belt and 1:1 pulleys.  I also bought a couple of alternate pulleys so that I could increase or decrease the wheel speed, but it seemed to operate nicely at just over half throttle.  I've attached a picture of the drivetrain for that boat which is the one in my avatar and in my "Introduce yourself " initial post.  The motors are not too expensive so if I need to change them for this boat they can be here in a week.

Thomas, I will be grateful for any help offered.  I am powering my boat with twin electric motors independently driving the two wheels so my steam boiler will be non functional.  I do want it to look proper though.

Damien, I have built many RC airplanes, but only one boat so I will be looking to learn from yours and others experiences during my build.

Navigation

[0] Message Index

[#] Next page

Go to full version