Alyn RLE Last and First

[JasonBModerator @jasonb]

Thanks, yes it would be nice to see some more actual building.

I’m actually a bit behind writing this one up as I have been waiting for the flywheel castings so have been doing some work on the Denny, got that fabrication machined and the flywheel is almost done.

[garyParticipant @gary44937]

well done jason. will you be showing the ignition set up in detail.  i notice this is often lacking in other engine builds. gary

[JasonBModerator @jasonb]

I will do as I intend to alter it slightly from what is mentioned on the drawings. I want to make it possible to advance and retard the timing but final details are dependent of getting the flywheel castings.

[Colin HeseltineParticipant @colinheseltine48622]

Jason,

In the background of your Denny picture I can see some thick wall tube.  Who is your source for this.  I am looking for 8 inch length of 3 inch OD, 2 inch ID.

Thanks

Colin

 

 

 

[JasonBModerator @jasonb]

That was the bit left over from making the furnace and cylinder, 2 1/2″ x 1 1/2″

It came from M-Machine, last couple of pages here though I can’t see your exact size

[JasonBModerator @jasonb]

Continuing with things up at the head end the valves were done in my usual way by putting a small ctr drill hole into some 303 stainless bar so the stock could be supported with the revolving ctr and a DCGT insert used as it can get in nice and close.

A 2mm dia insert was used to form a fillet where the stem meets the head and also to cut the 45deg seat.

While the valves were still part of the bar stock I used that as a handle to give them a quick lap with some 600grit silicon carbide powder and oil.

They were then saw off and held in a collet to face the head and then fitted from the back of the collet so the ctr drill hole on the stem could be turned away.

The rocker arm was cut to my new shape to allow for the inlet valve to be closest to the push rod, the curve allowing it to reach over that to the exhaust.

While I had the CNC going I also did the gocernor latch arm and the cam follower which also had two holes tapped for the latch.

All three parts went back into the manual mill to have the excess holding material milled away

The cam follower was drilled to take a spigot that will be formed on the end of the push rod

The latch arm was thinned down either side for looks more than anything

Lastly the under cut of the latch was machined using a flycutter with a suitably ground HSS bit

The reduced thickness could then be slotted and CSK for screws with enough length to the slot so it’s position can be adjusted.

[JasonBModerator @jasonb]

I decided that I would like a square push rod on my engine rather than the round one shown on the original drawings so a length of 4mm keysteel was ordered. A spigot turned on one end so that the bronze cam follower could be Loctited to it and the other end was drilled and tapped to take a small threaded adjuster. Rather than fiddle about with a small part in the 4 jaw I just drilled a bit of aluminium to the across corners distance of the rod and after sawing a slot down the side used that as a split bush.

The engine was screwed to the machining plate once again and clocked in true before finding it’s horizontal ctr line.

I slipped the cam gear and it’s pivot into place and touched off on the side of the gear then zeroed the DRO. I could then set my other heights relative to that.

I could then mill off the excess from the cylinder mounting flange and the rocker pivot bracket followed by a 4×4 slot for the rod to run in.

A few M2 tapped holes for the retaining blocks completed the work that needed to be done in that setup.

The two retaining blocks were just squared up from some off cuts of brass, drilled for bolts and a small ctr drilled hole added for a drop of oil to be applied. I knocked the corners off after the photo with a small file so that they looked like cast blocks.

[JasonBModerator @jasonb]

Another thing I wanted to add to my RLE was a pulley on the non governor side. I will modify the spokes of the cast flywheel to allow one to be fitted but while waiting for those decided to make the pulley.

I have quite a few 5kg cast weights from a multi-gym and although it is not the best cast iron in the world I thought it would do for this job. I piece was cut from one of the weights with my Femi bandsaw and then held in the 4-jaw to get it to the basic shape, here the inside has been turned with a 3degree “draft” to the edge and an insert with 0.8mm radius was used to leave a fillet between the inner edge and what will be the mounting lugs for that cast look.

 

I then held it the other way round in the 3-jaw and machined off the remaining corners before transfering to the [b]C[/b]uts [b]N[/b]ice [b]C[/b]urves (CNC) machine to shape the mounting lugs and drill their holes.

I probably should have gone 1mm lower with the profile cut as the “step” that can be seen is the fillet left from using the 0.8mm radius cutter.

It was not a problem as I had intended to go over the inner “cast” surface with the Dremel to texture it a bit so did the remaining fillet at the same time.

I wonder what is hiding in the other bits of that weight :thinking:

[DiogenesParticipant @diogenes]

..doesn’t look a bad piece of CI for a big flat casting.. ..and still plenty left, if it’s okay round the edges..

[JasonBModerator @jasonb]

It’s not the best iron, I would not want it for piston rings or a cylinder liner but OK for some things

The two flywheels arrived at the beginning of the week, they did look a bit rough and had a fair amount of thin flash so the first thing I did was to take a small cross pein hammer and carefully chip the flash off. This shows the one on the right after chipping and the left as delivered.

I then fettled the flywheel, I like to do this before any machining a sit saves marking the finish turned rim if you intend to leave that bright. It was mostly done with files and then a quick tickle with the Dremel equipped with a grinding bit, again one on the right has been fettled. There is a little more to do between the spokes where they meet the hub.

Where possible I like to hold flywheels by the inside face of the rim and get that to run true as it is not a surface that is going to be machined, this is another reason to clean them up first. With the 3-jaw’s jaws reversed it fitted easily and was just tapped on the side until it ran with minimal wobble.

My machining sequence was:

Rim OD, Rim Side both these done with CCGT inserts using the holders that make use of the two “spare” corners.

I then changed to a boring bar with 0.8mm corner radius CCGT insert and flattened off the side of the inner rim, this ended up 1.75mm below the side face of the rim.

The hub was then faced, spot drilled, drilled 6mm with a stub length drill, opened out to 9mm and then a boring bar used to take it out to final 10mm dia using the crankshaft material as a plug gauge to get the fit right which is tighter than a nominal 10mm reamer gives.

Lastly change to a brazed tip tool with 1.5mm nose radius, set the topslide to a few degrees and clean up the OD of the hub. Knock off all corners with Lathe file.

To do the other side I changed to the 4-jaw and got the flywheel OD running true before machining Rim side, recessed side, hub face, hub OD.

With two done it was time for a trial fit

 

[JasonBModerator @jasonb]

I needed a way to mount the belt pulley described a couple of posts previously so clamped the non governor side flywheel to the mill table and located it’s centre and ensured two opposite spokes were along the Y axis. The DRO made quick work of spotting, drilling and tapping the three holes at 120deg spacing and then I went round again with a 3-flute milling cutter to form a counterbore.

Some short lengths of 10mm steel were drilled M3 clearance and then bonded into the counterbores with JBWeld and left to set for 48hrs.

Once set the flywheel went back into the 4-jaw on the lathe to have the three bosses machined to length and also a small step turned that would locate the ID of the pulley.

and with the Pulley in place.

J

[JasonBModerator @jasonb]

I was not that keen on the look of the governor weights as shown on the drawing which replicate the old Gramaphone governor weights that Graham used on his original nore the bent metal bracket that swing on. So I drew something up along the lines of what I did on the 1/5th scale vertical IHC Famous many moons ago.

The bracket was fabricated from two pieces, first a flat plate that will fit around the crankshaft and attach to the inner face of the flywheel hub with screws.

To keep the clevises at each end lined up they were machined from one piece that then had the central section machined away after silver soldering.

I neglected to take a photo of the actual weights but they were turned from 8mm rod having a taper at each end which was blended into a parallel central section and then flat tongues milled at the extremities for the springs and adjusters. 4mm rod was soldered to these and at the other end of the rods were the blocks with the pivot holes and fingers that locate in the spool, first photo shows these pivot/fingers being machined

Add a couple of pivot pins and these are the main governor parts

The adjusters were turned from 4mm rod down to 2mm and threaded before milling the head flat, cross drilling for the spring and rounding over once they had been cut from the parent bar. The spring draw provided a couple of suitable springs that were cut to length and the ends bent into loops with two pairs of long nosed pliers.

[Author]

Posts