Machinist's Minutes: Quartering/stroke measurements on steam locomotive pins

This video shows how to do the measurements to find pin quartering/locations for steam locomotive wheels. If you need this video you are doing some niche work!

[@lembriggs1075]

You are too cool! Love tooling, tolerances, measuring, locomotives, your dedication to making these great videos, and your smiling enthusiasm! You guys are GREAT!!!

[@charleskutrufis9612]

This one makes me tired, glad it's YOUR problem. Thanks for the video.

[@donniev8181]

Here I thought the dog bone links were matching on both sides, I guess it's like top dead center on a car engine. Learn something new every day!

[@Manufacturingsite1]

Hello Amazing video and nice work

[@lwilton]

Keep in mind that in a wheel set, the diameter of all of the tires in the set must be identical, else one or more will be scrubbing on the rail. If you are being this accurate on quartering, you may want to put a Pi tape on those tires and see how far off they are. There are specifications for how far off the diameters can be. Also don't forget the bearing center distance on the connecting rods should nominally be identical, assuming the crank pin offsets from wheel center are all the same. If the pin circles don't match they might have compensated in the con rod lengths.

[@svenschlenkrich]

Well all I can see here is guess work. If you are not sure about the tolerances needed, you should ask somebody who know the numbers. I've been restoring steam locomotives as a professional for more than 20 years now and learned the basics of design, machining and maintainance from old books, maintainance manuals and regulations in archives. The tolerance for the 90 degree angle is +/- 2 arc minutes. The tolerance for the stroke of the pins depends on the actual size, bearing clearance and the wheel base. On such as small engine it should not be more than 10 thou. The quartering can be easily measured on a horizontal boring mill with a rotary table. Put the spindle with a dead center in it the center bore of the axle and zero the DRO of the z-axis. Move the spindle up until the center bore of the pin matches the dead center. The reading of the z-axis is your excentricity (half stroke). clamp the wheel set to the table and rotate the table 180°. Then you can repeat the procedure but move the spindle now sideways. With and Indicator on the spindle you can now measure the offset of the center bore of the pins and check if the angle and excentricity is within the tolerances. The bearing surfaces of the pins and axles are not suitable for measurements, the have usually resonable geometrical and shape errors that will have major impact on the measurements. For more infomation check my actual project blog: facebook.com/projekthilax

[@ebayselle]

I can cut a pie 10 times and still eat the whole thing

[@bobbob8229]

moderndaytinker here I endorse the level of accuracy this machinist is using. Sometimes measuring "close" compensates for other normal errors in the rest of the endeavor 😅

[@bobbob8229]

By the way -- you work the way I do😊

[@jamestregler1584]

😎 love the old stuff

[@lembriggs1075]

Great videos!

[@ParadiseRanchLV]

I lOVE trains!! Lol

[@davidboyce2007]

As re there any books you could recommend on steam engine type stuff? I want to get into steam powered sawmills and winches.

[@lwilton]

Look into Google Books for books on steam engines and locomotives from a century ago, say 1890 to 1920 era. There are all kinds of both academic and practical books from that era that have a huge amount of info. "Principles of Locomotive Operation" by Wood is not a bad place to start.

[@RogerMcMillan-e4x]

Railroad shop Practice by Frank A Stanley reprinted by Lindsay Publications Inc.

[@spencertoolandgrind]

I get having the drives correct.. but what if the tire is small on one large on the other?

[@rodiona8781]

I'm not a professional but I'd think because the wheels are angled it would stay on the track but you'd get more wear on one side more than the other due to it making more rotations per mile and more weight bearing down on that side. I'd assume it would also cause more wear on the track on that side as well.

[@servicetrucker5564]

It would run but not equally. The speed difference due to mismatched diameters will make the larger wheel run on its outside and the smaller wheel run closer to the flange. They’ll try to find a spot where the diameters are equal

[@ebayselle]

I was indicating a part tediously like you, and a guy jumped in and said, "Do I want him to do it. I was done just questioning myself

[@Blazefork]

We have a cafe in town that cuts pie in 7ths...I've never figured out why lol

[@benjaminzedrine]

Economics.

[@TaylorZalus]

So precision is just dividing your divisions?

[@CameronMcCreary]

What type of locomotive steam or diesel?

[@V8freaks]

steam - he is talking about cylinders and connecting rods...

[@JoeVespa-s3g]

Smallest rail gauge I have ever seen before

[@davidboyce2007]

Ha I love that "the lowest highest point". know what you mean though.

[@f.s.3197]

Almost 7/8 of a thousand😂😂😂 I'll Bet you would do this with millimeters to.😊 I'm German, so I am the Guy who cuts a hundredth,, on the indicator, in thenths. 😉

[@ke6gwf]

Yes, you most certainly can do this in metric, machinists use Base 10 anywhere in the world, and it literally doesn't make any practical difference, so there is no downside to him using USC and you using Metric, as long as you aren't having to work together lol But he can visualize USC and you can visualize metric, so you should each stick with what you are familiar with!

[@f.s.3197]

@@ke6gwf It s just a matter of practise and experience. lamenting on USC vs Metric is, in my mind, rediculius. Both systems work. Btw, What is math without fractional arithemtic? Complicated 😉

[@ebayselle]

The volunteer probably did not about critical aspects

[@ebayselle]

I just had a thought

[@ebayselle]

Put the pin at the top. Get the high point of the pin .Now, figure out how to measure other side

[@ebayselle]

Are those pins probably pressed in? Make them eccentric, then a problem keeping them tight?

[@ebayselle]

Put a strap on it for safety

[@WHJeffB]

0.100" difference in crank throw from one side to another??!! That's crazy! Someone misread their measuring tool? Or perhaps they boneheaded counting handwheel rotations? 0.100" is pretty huge... Sounds like these drivers should be removed from the axles and completely reworked. New axles, with slots and keys to key the wheels at 90° to one another. Bore out the crankpin mounting holes oversize at the correct center distance from the axle bore and make new crankpins... Not "easy" per se, but it's worth doing it right while you have everything disassembled.

[@ebayselle]

I never found a strong on

[@ebayselle]

Next time metal stamp