Search found 899 matches

by barts
Wed Oct 21, 2020 4:22 pm
Forum: Members' Websites and Boats
Topic: DetroiTug's Tug is going together
Replies: 382
Views: 194467

Re: DetroiTug's Tug is going together

A propane fridge uses heat (from either propane or electricity) via an absorption cycle to keep food cold. They're pretty standard in travel trailers. A small steam feed equiv. to 20k btu/day will easily run one; coolng the heat rejection coils with cold water rather than air will improve that numbe...
by barts
Sat Oct 10, 2020 12:03 am
Forum: Technical - Engines and Boilers
Topic: Hot wells
Replies: 14
Views: 1328

Re: Hot wells

I made a new hot well a while back for Rainbow, but have had no chance to try it out as yet.... the float valve is actuated via a ball chain from the float to allow the use of a large float in a small space. The hot well is about 6"x7" inches or so, and about 20" tall iirc. IMG_20180715_193910_1.jpg
by barts
Thu Sep 24, 2020 4:48 am
Forum: Technical - Engines and Boilers
Topic: Ancillary vacuum appurtenances
Replies: 3
Views: 358

Re: Ancillary vacuum appurtenances

I would certainly consider a steam ejector as a good idea on a plant that needs vacuum to start reliably. The use of separate engine driven pumps to provide both vacuum and boiler feed was common in larger vessels; I don't think large triples could start w/o vacuum and a cleared condenser. Alan's se...
by barts
Thu Sep 24, 2020 4:40 am
Forum: Technical - Engines and Boilers
Topic: Boiler Lagging
Replies: 7
Views: 769

Re: Boiler Lagging

Note that wood is a traditional insulating & covering material for firetube boilers. A layer of fiberglass or fiberfrax underneath will make the boiler more efficient. Here's an example of a locomotive with wooden lagging: https://en.wikipedia.org/wiki/Wood_lagging#/media/File:GWR_Firefly.jpg - Bart
by barts
Thu Sep 24, 2020 12:41 am
Forum: Technical - Engines and Boilers
Topic: Hot wells
Replies: 14
Views: 1328

Re: Hot wells

If you're using a float value so you have automatic bypass control and you pump water into the boiler for make-up, the necessary volume is really room enough for your float and bypass valve. Smaller hotwells absorb less air. If you add make up to the hot well manually, you'll want enough volume so t...
by barts
Fri Aug 21, 2020 4:34 pm
Forum: Technical - Engines and Boilers
Topic: Looking for some help
Replies: 3
Views: 606

Re: Looking for some help

Hi bigbob - Check if your school uses steam heat. While attending UC Davis, we used 100+ psi steam from the heating plant for ag engineering experiments involving blanching 50-70 lbs of plums at a time prior to solar drying. We boiled 40 gallons of dilute NaOH from cold in 5 minutes. This will be mu...
by barts
Tue Jul 28, 2020 6:37 pm
Forum: Technical - non Engines and Boilers
Topic: Vintage Steam Engine.
Replies: 16
Views: 2147

Re: Vintage Steam Engine.

<aside> Does anyone ever use plastigage when setting up steam engine bearings.... I used this stuff many decades ago to double check clearances on an engine during rebuild; it seemed to work well enough. Or was that just for people who didn't have a good set of micrometers and telescopic gauges? - B...
by barts
Sat Jul 25, 2020 4:08 pm
Forum: Technical - non Engines and Boilers
Topic: Vintage Steam Engine.
Replies: 16
Views: 2147

Re: Vintage Steam Engine.

Bart, my problem with this one is that it appears it may have come from the manufacturer that way! :shock: There is very little ovality in the bearing, maybe 0.0005" indicating that is near enough the size it was machined to. Wow... that's alarming. I'd make sure the engine is otherwise true and or...
by barts
Sat Jul 25, 2020 4:07 am
Forum: Technical - non Engines and Boilers
Topic: Vintage Steam Engine.
Replies: 16
Views: 2147

Re: Vintage Steam Engine.

With 0.010" clearance on a 3" crankpin you'll definitely get a healthy 'clonk'. From http://edge.rit.edu/edge/P14453/public/Research/2-_LEADER_-_Understanding_Journal_Bearings.pdf: The basic guideline universally used for diametral journal bearing clearance is 1.5mils-per-inch of journal diameter. T...
by barts
Fri Jul 24, 2020 7:13 pm
Forum: Technical - Engines and Boilers
Topic: Machinest Question
Replies: 15
Views: 2222

Re: Machinest Question

> Better to use tap T-handles with a center drilled in top of the stock then use a live center in the tailstock to hold, that supports it straight. Typically on small holes I just spin the lathe chuck by hand and catch it up with the tailstock. It allows the operator to feel whats happening. Yup; I ...