Hello From Edmonds, Washington State, USA

[SnagboatMike]

Several steamboat modelers on other forums suggested that I come over to Paddleducks to share my love of steamboats. I'm currently 2 years into a scratch-build of the US Army Corps of Engineers sternwheeler W.T. Preston. She was a snag boat serving on the waters of Puget Sound and surrounding rivers doing dredge work and removal of log jams and deadheads floating in the navigable waters around Western Washington. My model, built in 1/32nd scale is nearing completion. What is unique about her is that she can do virtually everything that the full-size Preston could do. The slow speed, long throw valve steam engine is a miniature replica of the 14" bore, 72" stroke Gillette & Eaton steam engine. There will be no gears, pulleys or drive belts used. The paddle wheel connects directly to the pistons via pitman arms. Steam is supplied from a Maccsteam Ltd, 3 1/2" horizontal boiler. An attenuator controls fuel supply to the boiler. A Water Level Detection System is installed on the boiler that operates an electric boiler feedwater pump. She has 51 lights, all controlled by a dedicated 12-channel lighting control system. This enables me to set the running and navigation lights appropriate to operating conditions, all 12 of them. The remaining lights are found in cabin areas and external work lights.  I'm using a Spektrum DX10t to operate rudder, throttle, reversing gear, steam whistle, raising and lowering anchor spuds (see photos) cylinder drains, 3 winch drums (3 ESCs) on the steam donkey on the forward work deck, and a turning engine that swings the crane boom left and right. A SM1000 Telemetry Module monitors battery voltage in the receiver and 12V gel cell powering the winches. It also monitors boiler temperature set to warn me if the temperature at the top of the flues exceeds 135˙C, indicating that this part of the boiler is uncovered.  I have the Spektrum iPhone monitor that alerts me to a dangerous boiler temperature through a voice warning. I stick the phone in my pocket and hear audio alerts without having to look at anything.The boat is 63 inches long and displaces 37 pounds.  So far 1700 hours have gone into building the model Almost everything is hand made including brass etched parts I made for various small parts. In order to build the wood plank on frame hull, I set up a miniature saw mill and milled all the lumber from 70-year old Alaska Cedar 1" x 6" fencing. The paddlewheel is made from brass spokes, hubs and hex paddle shaft. The 48 paddle blades are custom cut from Alaska Cedar. The Paddlewheel hubs were designed in CAD and cut on a waterjet table. A total of 820 individual parts makes up the 6.3" diameter x 7.5" wide paddlewheel. The pilothouse is an exact replica of the original including a chart table and storage cabinet. A 1/32nd scale nautical chart is spread out on the table. A mug of coffee sits on the chart. I've installed a temporary electric drive system, thus allowing me to do sea trials to check trim, stability and paddlewheel performance. I'll also be testing the 5-rudder system for helm control and sea keeping. All that gets ripped out when the steam engine is finished. The steam engine bronze casting are being done this week. The 2-cyl. engine has a bore of 5/8", a little larger than scale, done for efficiency reasons and a scale stroke of 2 1/4". Paddle speed will be around 20 ~ 30 rpm. Sorry for the long intro post, but there is a lot going on inside the model. I'll post a build log separately.

[Eddy Matthews]

What a gorgeous looking model Mike!

I've always liked the American sternwheelers, and your model is a fantastic example that you should be proud of!

Welcome to Paddleducks, I'm already looking forward to you build log...

Regards
Eddy

[derekwarner_decoy]

Hi PD's ....& welcome Mike...... ......

Just looking at the model wheel...I think I see nine floats in 180 degrees ....so 9 x 2 x 6 x 2 = 216 U Bolts faithfully reproduced just holding the floats to the spokes..so I certainly understand the 820 parts to make  the wheel set 

When you note  the estimated...."Paddle speed will be around 20 ~ 30 rpm" ...I assume this is a prototypical rpm for the original full size vessel.......in model scales we need to adjust speed to a function of the scale ......so with a 1/32 scale model.....may need a paddle shaft rpm of ~~~to 150 rpm....you may have considered this...or it may be worth considering dependent on the trials of the electric drive... assumed at the same 20>30 rpm

We look forward to see progress on your 5/8"bore x 2 1/4"stroke engine & will be interesting to many members  ...along with detail on your boiler level control system

I see you have a quality boiler from Maccsteam.........interestingly, have you looked at the simple calculation for determining steam requirements relative to engine speed from the Maccsteam WEB site?

Don't be sorry for the post intro...........we find such posting good value & interesting ..............Derek

[SnagboatMike]

Thank you for all the comments.  The paddlewheel also uses 384 brass 00-90 hex nuts on 192 "U" bolts and 96 backing plates to hold the 48 paddle blades to the 64 brass spokes. I built the paddle wheel pretty much the way they did in 1929 on the actual Preston. As far as operating rpm, the full size vessel paddle wheel operated at a maximum speed of 16 rpm. I've seen other similar models operating at 40 to 60 rpm giving a nice scale speed. 150rpm is way too high for what I'm trying to achieve. My steam plant is sized to deliver enough steam to operate the engine at a maximum speed of 100 rpm with a comfortable margin.  Upcoming sea trials will give me a very good idea of what 50 to 60 rpm will achieve. The temporary electric drive will be able to spin the paddlewheel at this speed. You can see a 1/32nd scale sternwheeler a little shorter than mine on YouTube at: http://www.youtube.com/watch?v=3yiISP_ZKR4 It is exactly what I'm trying to achieve. His boat operates at just 60 rpm and looks fantastic. I've attached a few photos of the paddlewheel.

SnagBoat Mike