Piston crown thickness measuring thingie.

[tonyfoale]

Just a quickie tonight.
Normal calipers and micrometers are a bit useless when it comes to measuring piston crown thickness because the skirt and gudgeon pin bosses get in the way. To circumvent these problems I made a simple device to use with a dial gauge which does the job well and has also found other uses with various difficult to measure do-dads.



The upright which looks like a multi-stage space rocket is shaped as it is for a deeply technical reason. It's the way that it came out of the scrap box.
To use it is just a question of setting zero on the dial gauge, lifting the plunger and inserting the piston over the pillar and gently lowering the plunger. The piston can be moved around to get the thickness at different areas of the crown. Simple but very effective.

[Frank S]

We had a thread a while back where one the solutions amounted to very nearly the same as your tool
http://www.homemadetools.net/forum/m...aphragms-54209

[tonyfoale]

When I first posted this tool I couldn't find the pix. showing it in use. They surfaced tonight and so here are a couple. I think that the ease of use is pretty obvious.