Search found 1069 matches

by barts
Thu Jul 20, 2023 5:44 pm
Forum: Technical - Engines and Boilers
Topic: Boiler Safety
Replies: 2
Views: 5204

Re: Boiler Safety

https://en.wikipedia.org/wiki/Fatigue_(material) also has a nice treatment of fatigue failures, including some notable examples. When I was in school studying mechanical engineering ('78-'84), it was felt that a fatigue limit stress in mild steel (below which no fatigue failures are observed at 1 mi...
by barts
Fri Jun 30, 2023 3:12 pm
Forum: Technical - Engines and Boilers
Topic: Cylinder packing question
Replies: 4
Views: 5941

Re: Cylinder packing question

I've had excellent luck with simple thin PTFE faucet packing on Otter's engine. Yes, a bit of tightening is sometimes required as things warm and settle in. Keep in mind that PTFE packings are much more "plastic" than traditional graphite flax and the like; the PTFE seems to flow into any air spaces...
by barts
Tue Jun 20, 2023 6:06 pm
Forum: Technical - non Engines and Boilers
Topic: new boat launch-propeller question
Replies: 18
Views: 14569

Re: new boat launch-propeller question

These discussions have been very helpful. Today I bought a prop on E-bay, 12rh15 pitch. Although the rule of thumb would be that a 18 pitch would be best I was concerned about overloading my boiler, which is on the small size. It was only $140 with shipping so not a big investment to try out. Thank...
by barts
Mon Jun 19, 2023 6:30 pm
Forum: Technical - non Engines and Boilers
Topic: new boat launch-propeller question
Replies: 18
Views: 14569

Re: new boat launch-propeller question

A two blade prop would be alot easier to make than a 3 blade but I do not know if that would work for my boat. I would think I would need a larger diameter than 12". How much room do you have w/ the current shaft & skeg? The folks at Michigan Wheel can make you a prop to fit the current shaft & ape...
by barts
Thu Jun 15, 2023 2:12 pm
Forum: Technical - non Engines and Boilers
Topic: new boat launch-propeller question
Replies: 18
Views: 14569

Re: new boat launch-propeller question

"Propeller Handbook" is indeed well worth examining; the math is pretty empirical. In general, for displacement boats you want to run the largest practical propeller diameter. One thing to note; the most efficient props in abstract are typically near 1:1 pitch/diameter ratio, but most small steamboa...
by barts
Tue May 23, 2023 3:54 pm
Forum: Technical - non Engines and Boilers
Topic: Preparing for the Steaming Season
Replies: 5
Views: 6854

Re: Preparing for the Steaming Season

I don't like protruding heads on spinning shafts from a safety standpoint, especially when it may be exposed during operation. If the collar/hub is thick enough, two short setscrews in the same hole will often prevent loosening. Alternatively, blue Loc-tite does an amazing job on machinery that isn'...
by barts
Tue May 09, 2023 2:20 pm
Forum: Technical - Engines and Boilers
Topic: Advice on resetting Intake/Exhaust Valves on a Vertical Walking-beam Engine
Replies: 4
Views: 4877

Re: Advice on resetting Intake/Exhaust Valves on a Vertical Walking-beam Engine

So if I understand things correctly, you manually control admission - intake - events when starting out, and once the engine is running at speed, you let the cams handle matters. Those presumably cut-off steam prior to full stroke, reducing power somewhat but using less steam. The boat itself in con...
by barts
Tue May 09, 2023 3:52 am
Forum: Technical - Engines and Boilers
Topic: Advice on resetting Intake/Exhaust Valves on a Vertical Walking-beam Engine
Replies: 4
Views: 4877

Re: Advice on resetting Intake/Exhaust Valves on a Vertical Walking-beam Engine

Does this engine have a variable cut-off gear, or can one select between different cams?

In any case, I'd start with the exhaust valves just opening at bottom dead center, and closing as late as possible. Compression should be limited since the engine turns so slowly.

- Bart
by barts
Fri May 05, 2023 6:18 pm
Forum: Technical - non Engines and Boilers
Topic: Flotation
Replies: 11
Views: 14419

Re: Flotation

This is my first boat (not counting my canoe) and I wanted to make sure I did not do something foolish.
Bringing along a friend in another boat is always a good plan on those initial outings...

Good luck!

- Bart
by barts
Fri May 05, 2023 3:51 am
Forum: Technical - non Engines and Boilers
Topic: Flotation
Replies: 11
Views: 14419

Re: Flotation

The only steamboat I've seen sinking (other than slowly at the dock due to leaks :) ) is one that ran into a submerged piling and stove in some delicate planking. They ran for the shore and waited until low tide to patch the hole; refloated at high tide and steamed full speed to the launch ramp. The...