Wooden piston with wooden connecting rod

[hackberry jake]

My brothers birthday is a couple months away and I would like to make him something neat. I was thinking a replica of a small block Chevy piston and connecting rod that actually actuates. I have cherry, maple, walnut, osage orange, sycamore, and cedar to work with. I know I can make the face and outside of the piston on the lathe, but how would you remove the material inside the piston and shape the connecting rod? Chisels and sandpaper sound time consuming and a router seems like it would be too bulky.

[Migal]

Dang congrats on your brothers birthday!!! I think that is a wonderful idea only can think of my friend that builds miniature steam engines with a lathe. he bought his on ebay good luck!

[Ianab]

Sounds like an interesting challenge 

The con rod is easy enough.

As for the piston.... That's more interesting.

I would consider making it a laminated construction. The bottom skirt, the part with the gudgeon pin, the ring grooves, then the actual top of the piston. This would let you cut out the inside form, and sand it smooth etc relatively easily. Get the holes, face and bulge for the gudgeon pin made etc Then glue the 4 or 5 pieces together and finish the outside perfectly round with the lathe.

Alternatively you could make it up with the laminations running vertical? Again shape the internal structure before assembly, and turn it round later.

Then a larger dowel though the piston to connect the con rod.

Look at how wood turners make segmented turnings for some ideas.

A little rotary tool (ie dremel) with a sanding head is good for those fiddly inside sanding jobs.

Ian

[Texas Ranger]

vertical would allow the gudgeon pin mound to be formed before the turning.  Seems like it would make it easier, also allow some mix of woods for a "woody" effect.

[Don_Papenburg]

Laminating is the way . get a book on patternmaking for foundry work . Very interesting wood working  there.