Turning radius

This forum is dedicated to the Live Steam Hobbyist Community.

Moderators: cbrew, Harold_V

Post Reply
hoppercar
Posts: 616
Joined: Sun Jul 22, 2018 4:09 pm

Turning radius

Post by hoppercar »

How do you figure, the minimum turning radius, for the driver wheel base of a live steam locomotive?...is there a simple formula for this ?
User avatar
Bill Shields
Posts: 10460
Joined: Fri Dec 21, 2007 4:57 am
Location: 39.367, -75.765
Contact:

Re: Turning radius

Post by Bill Shields »

do you have a CAD system available to you?

it is actually easier to draw than explain

you need to know the fixed wheel base, the side-2-side play in the axles and the 'nominal' rail spacing.
Too many things going on to bother listing them.
BClemens
Posts: 475
Joined: Sat Oct 08, 2016 10:04 pm
Location: Gloucester, VA (Sassafras)

Re: Turning radius

Post by BClemens »

I believe the best way to 'calculate' the minimum turning radius of a specific locomotive is to lay the drivers out (such as the left side drivers) on a plan drawing (from above) in the largest scale that you can with great detail for tread profile. In CAD you're able to do this in full scale. At the centerline of the rigid wheelbase, include the half of the total lateral movement of each wheel set. From there the maximum radius can be plotted from flange radius locations then using CAD - make the minimum radius circle from those points. Sort of a crude way but Machinerys Handbook has formulas to do this type of math if you would rather do it that way.

Sorry I could not find the actual diagrams and math but I searched through the books that I 'knew' it was in - not... I have that data and will bring it up here - we are in the middle of a move to larger property - for track!
BC
Bill, we are posting at the same time with similar ideas.
STRR
Posts: 469
Joined: Thu May 24, 2007 9:01 pm
Location: Westminster, CO

Re: Turning radius

Post by STRR »

Hoppercar,

I sent you a PM with a web site link. See if that answers your questions. Also, if you have access to Grand Scales Quarterly Issue #29, Kell Schmidt wrote a 5 page article on minimum radius curves. He did a pretty good job on the whole subject.

Good Luck,
Terry
Post Reply