Ouch - that takes some patience; at least you have a power traverse :). I remember doing the same for Otter's boiler (well, it was only 110 holes iirc ) 27 years ago on a mill-drill. I had a very stubby 5/8" drill Latrobe drill bit that saved the day wrt clearance; putting the drum directly on the t...

The marine two-part polyurethane finishes are very good, hard and long lasting. My brother has used the Interlux two part systems with excellent results; hand rolling and tipping; many have asked if he sprayed the finish. As always, surface prep is critical so follow the directions. Note also that c...

Equally important is the centerline of the valve rod should be as close as practical to the plane of the cylinder face. This imposes a more a linear force between the two rather than a tendency to rock the valve on it's ends. This is where the designs that have a square or rectangular piece that su...

Despite their deficiencies, note that basic slide valves require minimal precision equipment to manufacture, esp. in larger sizes. The interior cavity can be as-cast. The outside can be the same, or filed to the desired dimension. The sliding surfaces could have been scraped into whatever degree of ...

On additive fabrication: Those who are not familiar with Kozo Hiraoka's excellent series in Live Steam back in the 70s and 80s would do well to examine one of his books or magazine artiles. Although somewhat smaller in scale than stuff many of us are used to, his fabrication techniques which rely ex...

The old adage: Slide valves wear in Piston valves wear out A piston valve in good fit is far more efficient though. A slide valve with 5 square inches of face at 250 psi has 1250 pounds of force exerting on it, quite a loss in horsepower. I did some looking for coefficients of friction measured on ...

Well, piston valves do have their downsides: * w/o rings, they are quite sensitive to wear and become leaky easily (Otter's engine is like this). * with rings, machining the ported valve sleeve is a bit tricky as is fitting and pressing it in. * no automatic safety valve like a slide valve; if your ...

I see old Cromflex piston rings, but nothing named 'Courflex': https://trademarks.justia.com/715/99/cr ... 99043.html

- Bart

Followup - The valves arrived today via FedEx (free shipping since order was just over $100). The valves are shown here with my new steam siren... want to try the combo on air tomorrow. Rainbow will have two noisemakers when she goes back in the water next year (need to get my shop build and machine...

I was looking for a nice whistle valve for Rainbow's new steam siren and found a cleaning supply house that has reasonable prices on new United Brass whistle valves. I used the same brand of valves on Otter when I built a new boiler in 1995, and have been quite pleased. Anyway, here's a link: https:...