Search found 894 matches

by barts
Fri Aug 21, 2020 4:34 pm
Forum: Technical - Engines and Boilers
Topic: Looking for some help
Replies: 3
Views: 287

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: 1237

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: 1237

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: 1237

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: 1318

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 ...
by barts
Wed Jul 22, 2020 6:18 pm
Forum: Technical - Engines and Boilers
Topic: Machinest Question
Replies: 15
Views: 1318

Re: Machinest Question

This web page has some help with tap nomenclature, which can be confusing. https://www.natool.com/tap-style-guide/ I've used spiral point taps by hand, in portable drills and in my lathe w/ excellent success on aluminum and mild steel. In the lathe, I use a tap wrench to hold the tap, and if the tor...
by barts
Tue Jul 21, 2020 8:04 pm
Forum: Technical - Engines and Boilers
Topic: Steam Pressure Regulating Valves
Replies: 5
Views: 666

Re: Steam Pressure Regulating Valves

I made my own regulator from a standard gas (oxy?) pressure regulator and a reach rod & remote valve (stainless ball in a tee) for Otter, following Allan Gregg's design.

I wrote this up in steamboating iirc; I'm in WA so don't have the details handy.

- Bart
by barts
Tue Jul 21, 2020 7:58 pm
Forum: Technical - Engines and Boilers
Topic: Machinest Question
Replies: 15
Views: 1318

Re: Machinest Question

This works like a treat.... if you have a spiral point 'gun' tap it helps, and go for tap drill size for 60% thread... and your favorite tapping fluid, of course.

I've tapped 1/2" holes in 1 1/4" aluminum plate this way.

- Bart
by barts
Tue Jun 02, 2020 3:04 pm
Forum: Technical - non Engines and Boilers
Topic: How to chose gear wheels respective to torque?
Replies: 5
Views: 817

Re: How to chose gear wheels respective to torque?

Hi Steam Captain - Note that gear train (gears meshing together to transmit power) design can be tricky, esp. when running at engine speeds and transmitting significant power. As a result, most people use completely enclosed gear boxes designed as a unit for such service. For tasks such as driving p...
by barts
Sat Apr 18, 2020 5:07 am
Forum: Technical - Engines and Boilers
Topic: Bearings !
Replies: 4
Views: 1536

Re: Bearings !

You might take a look at PV values for your bearings; so long as you're within the safe values for the bearing materials and the supply of oil is adequate, these will likely be ok. Extra clearance causes noise pretty quickly, of course. The little ends are tricky, with very little motion to set up a...