Search found 1069 matches

by barts
Tue Nov 13, 2012 2:31 am
Forum: Technical - Engines and Boilers
Topic: Reflex gauge
Replies: 50
Views: 35399

Re: Reflex gauge

The other thing to keep in mind is that we're not in mid-ocean or mid-gale, and the degree of serviceability needed under pressure is much less than in shipboard installations. I simply don't consider changing the reflex gage glass under pressure to be an important design consideration. I don't carr...
by barts
Sun Nov 11, 2012 7:49 pm
Forum: Welcome
Topic: Headed to London
Replies: 9
Views: 10807

Re: Headed to London

The third floor of the Science Museum in London has a large collection of steam engine builder's models.... well worth a (free!) stop in. Plus lots of full scale stuff: http://www.sciencemuseum.org.uk/visitmuseum/galleries/energy_hall.aspx I'll be in London on business just after Thanksgiving... hop...
by barts
Fri Nov 09, 2012 4:26 am
Forum: Technical - Engines and Boilers
Topic: Reflex gauge
Replies: 50
Views: 35399

Re: Reflex gauge

I use a 300 psi rated solid bronze reflex glass. After some thought, I eliminated the shut-off valves between the boiler and the reflex gage as not materially making the setup any safer or stronger. This approach may not appeal to you, but it did allow me to mount the heavy gage glass much closer to...
by barts
Thu Nov 01, 2012 1:34 am
Forum: General Steamboat stuff
Topic: Machinery Layout
Replies: 11
Views: 13397

Re: Machinery Layout- doing trim calculations

The folks providing your plans should be able to give you the center of buoyancy for the hull; this shifts slightly rearward with increasing displacement but usually not too much. You can then calculate moments (weight * distance to center of buoyancy), adding weights ahead of the center and subtrac...
by barts
Wed Oct 31, 2012 4:48 am
Forum: Technical - non Engines and Boilers
Topic: Propeller Math Reality Check
Replies: 37
Views: 35287

Re: Propeller Math Reality Check

One of the nice things about steam engines is that they develop maximum torque at stall... so fitting an under pitched prop. to allow for headwinds, etc. is not needed. If your progress is slowed by either wind or seas, the boat (and engine) will slow somewhat... but since the torque curve is rising...
by barts
Mon Oct 29, 2012 3:03 pm
Forum: General Steamboat stuff
Topic: Otter spends the weekend at Elkhorn Slough, Calif.
Replies: 4
Views: 5282

Re: Otter spends the weekend at Elkhorn Slough, Calif.

We had no problems; I've run aground there once so I was checking every so often w/ the paddle, but never touched bottom. Otter only draws perhaps 20". There are definitely places that are quite shallow and it pays to keep a sharp lookout when not distracted by all the wildlife.
by barts
Mon Oct 29, 2012 4:51 am
Forum: General Steamboat stuff
Topic: Otter spends the weekend at Elkhorn Slough, Calif.
Replies: 4
Views: 5282

Otter spends the weekend at Elkhorn Slough, Calif.

Pictures from this weekend's steamboating in Elkhorn Slough.

Photos by Barbie Paulsen (the missus)/

https://docs.google.com/folder/d/0B2LkT ... k3ZkE/edit
by barts
Thu Oct 11, 2012 8:46 pm
Forum: Technical - Engines and Boilers
Topic: Sealing Pistons and Valves
Replies: 5
Views: 5411

Re: Sealing Pistons and Valves

I've used gaskets (designed for steam - Garlok) and high temp (500F) automotive silicone seal. Both worked
very well on flat smooth machined surfaces as I expected.

- Bart
by barts
Tue Oct 09, 2012 5:07 am
Forum: Technical - non Engines and Boilers
Topic: Propeller Math Reality Check
Replies: 37
Views: 35287

Re: Propeller Math Reality Check

4.5 hp should be ample power for your boat, using a 3 hp per ton estimate. At 450 rpm this means a BMEP of 50 psi, which is ok for a single running at 150 psi or so. Gerr says this will produce 5.35 knots. Your boat is pretty heavy to go fast. Note that slowing down to 300 rpm will produce 3 hp, whi...
by barts
Sun Oct 07, 2012 9:15 pm
Forum: Technical - Engines and Boilers
Topic: Riggs Patent Reversing Gear
Replies: 1
Views: 3289

Re: Riggs Patent Reversing Gear

For small engines, I just give it a spin w/ my hand :). If I had a boat where the
engine was too big to jog or where I needed to be at the wheel rather than
next to the engine, I'd fit a permanent magnet motor so it would function as
either a generator or a "starter" motor.

- Bart