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April 01, 2020, 13:00:10 pm

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Another mystery engine...

Started by PDR, March 25, 2020, 15:22:22 pm

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itsme and 1 Guest are viewing this topic.

PDR

There are no shortcuts on the long, hard road to success. But if your dad's rich there could a limo service...

clive_f

that looks to be a home brew to me .

A very well made one it has to be said.

regards Clive

PDR

Quote from: clive_f on March 25, 2020, 16:15:53 pmthat looks to be a home brew to me .

Bullseye

QuoteA very well made one it has to be said.

Modesty forbids...

But did you spot the slightly unusual feature of this (unfinished) engine?

PDR
There are no shortcuts on the long, hard road to success. But if your dad's rich there could a limo service...

THE BLACKBIRD

needle valve on the cylinder  head
The man that never made a mistake
Never made anything

British Victory

Is it s diesel and htf do the valves poppet?
there's only one f in RCMF,
               John

PDR

Yes, it's a 4-stroke diesel.

The valves are operated by the pushrods and rockers on the rocker pedestal that I have not yet made...

PDR
There are no shortcuts on the long, hard road to success. But if your dad's rich there could a limo service...

paulinfrance

So with 'lockdown' we will be getting a thread of this engine till it's finished and running ?. :af
Mode 2 THE only way to fly

PDR

Sadly I am able to work from home, so no. There are some bits/materials that I still need which I probably won't be able to get until things get back to normal.

PDR
There are no shortcuts on the long, hard road to success. But if your dad's rich there could a limo service...

The Saint. (Owen)

Electrickery is the work of the devil.
Proper aeroplanes are powered by engines.


PDR

To be strictly accurate - it was started by a customer of a clubmate who then developed alzheimer's, so I've been completing it.

PDR
There are no shortcuts on the long, hard road to success. But if your dad's rich there could a limo service...

The Saint. (Owen)

Electrickery is the work of the devil.
Proper aeroplanes are powered by engines.

PDR

Don't hold your breath - I need some bits that I probably won't be able to get until things return to normal.

PDR
There are no shortcuts on the long, hard road to success. But if your dad's rich there could a limo service...

The Saint. (Owen)

Electrickery is the work of the devil.
Proper aeroplanes are powered by engines.

PDR

March 28, 2020, 18:40:28 pm #14 Last Edit: March 28, 2020, 18:44:33 pm by PDR
One on the minor things this engine is short of is a piston - in this case a lapped, cast iron one. This is a relatively simple bit of machining which in past projects I've finished off using a Sunnen honing machine in a friend's workshop. But the friend is 15 miles away, in his late 60s and has some medical issues, all of which mean that his workshop isn't currently available to me so I will need a Plan B.

Some years ago I came by a pair of aluminium sand castings that are the basis of a Dalpena-type external hone plus a length of 1/4" square honing stone, but never bothered doing anything with them because I had access to the Sunnen. So after doing some design sketches I spent today making this:





PDR
There are no shortcuts on the long, hard road to success. But if your dad's rich there could a limo service...

Gaspin


PDR

It certainly does. I'm currently building two dividing heads* (a stand-alone one for the mill and a headstock divider for the lathe) which share some common components - mainly the disk, sector arms, plunger arm and a micro-divider with a secondary gear. Both were part built projects that I took over, and I found that the main sleeve bush on the headstock divider was around a thou too large to take the secondary gear from the VDH. I didn't want to mess with the gear because it already fitted the VDH, and skimming a thou concentrically takes a lot of careful setting up. But simply spinning the sleeve at 700rpm and giving it two 5 second bursts with the hone (using cutting oil) took precisely 0.005mm (eight tenths of a thou) off the OD and a fit in the gear that is closer than some piston/liner fits.

So I'm very pleased with it.

PDR

* both are George H Thomas designs - the stand-alone divider is the well-known "Versatile Dividing Head" or VDH
There are no shortcuts on the long, hard road to success. But if your dad's rich there could a limo service...