Minnie Traction Engine – Piston

[Malcolm FarrantParticipant @malcolmfarrant93389]

I am gradually moving foreward. Today's puzzle is the Piston.

Page 143 of Mason's book shows a drawing for the Piston. In it there is a 5/32 x 40 hole, whch continues thru the piston. My confusion is why is it necessary to go all the way thru. If the Piston rog is screwed in from left to right (page 143) it then leaves a hollow at the Right side. It seems to me (and I am obviously wrong !!) that it only needs a 3/16 length of 5/32 x 40 .to accomodate the Piston Rod.

What am I not understanding ?

In anticipation many thanks and best wishes.

Malcolm Farrant

[Malcolm FarrantParticipant @malcolmfarrant93389]

[JasonBModerator @jasonb]

Look at the end view which shows a 5/32" Hole (not threaded)

Then look closely at the hidden detail lines on the side view and you will see that the 5/32" plain hole goes half way through from the right before changing to a 5/32 x 40 thread.

having the plain section of hole does two things. 1. it guides your tap 2. it registers against the unthreaded part of the piston rod and again helps line that up.

[Malcolm FarrantParticipant @malcolmfarrant93389]

Jason, as always my BIG thanks. Now understood and sorted.

Hope you have a VERY happy Christmas and a peaceful 2019

Best wishes Malcolm

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