Member postings for David K

Master con rod is placed onto the crank pin and the big end bearing screwed into place.

The crankshaft can now be placed into the end of the alloy tube and slowly pushed
through so the tube is replaced by the crank. The crank pin is held at TDC and hopefully
it will engage with the cam still held at TDC by the taped followers.

The second main bearing plus its carrier is then pressed into place, this will
be held in place by three of the cylinder mounting bolts.
I cannot now see the camshaft so I have run some sticky tape around the outside
of the cam followers so they press against the cam and hold it steady.

The Cam followers in their bushes are pressed into place from the outside.

This tube is pushed up through the bottom bearing and the cam is dropped in lining
up the gears with the centre punch marks which are top / bottom dead centre

I turned an Alloy tube to hold the camshaft in place

I am now ready to build up the engine.
First I fit the 'ring gear' held by 8 M2 screws

With the bob weight placed on the crank pin the counterweight falls to the bottom
as it is heavier

I then slowly turned down the counterweight testing between cuts until the crank
can be placed in any position balanced.

I then turned a bob weight to 27.82 grams

Weight to be balanced

1/2 x reciprocating parts 13.378g

1 x rotating parts 14.335g

Total to be balanced 27.822g

Master rod total weight 100% 6.86g

Master rod upper half 43% 2.95g

Master rod lower half 57% 3.91g

2 Slave rods total 100% 4.49g

2 Slave rods upper half 50% 2.245g

2 Slave rods lower half 50% 2.245g

Reciprocating parts

3 Pistons 12.42g

6 Piston rings 1.17g

3 Wrist pins 6.22g

3 Small end bearing 1.97g

1 Master rod upper half 2.95g

2 Slave rods upper half 2.245g

Total Reciprocating parts [ 26.975 ]

Rotating parts

1 Big end bearing 4.08g

2 Knuckle pins 2.59g

2 Small end bearings 1.51g

1 Master rod lower half 3.91g

2 Slave rods lower half 2.245g

Total Rotating parts [ 14.335 ]

Please don't , I really am a novice when it comes to Engineering.

The 'PIP' plans come with substantial build notes which explain each step of the build , I am just good at following instructions.

Balancing the engine,
I bought a little 'jewlers scale' off E Bay so I could weigh each part.

Rather than explain I will just re print the chart from the plans with the weights
filled in.

Picture showing how the diffuser is driven from the crankshaft big end.

With the drive pin and bearings fitted I can then balance the fan by putting small
off cuts of steel rod into the holes drilled opposite. These will be fixed into place
with Loctite.

Back to the lathe the fan is parted off then I had to make a fixture to hold it
onto the rotary table.

Now I can mill out the back of the fan to create the passage for the air/fuel to pass through.

The mill is moved along the 'y' axis and a second set of cuts make up the rear of the blades

Then its just a matter of removing the waste between the fins

The rotary table is then placed horizontally and a 4mm hole is drilled .312 inches off centre,
this is the same measurement as the stroke of the engine as the fan is driven from a pin
inserted into the big end . You will see this in a later picture.
The table is then tilted 15 degrees and a 3mm end mill is used to start cutting the fins at
30 degree intervals.

The piece is then transferred to a rotary table placed on the mill table vertically.
A series of holes are drilled 15 degrees apart either side of the 180 degree mark.
These holes will have small pieces of steel inserted in them later to enable balancing
the fan.

Starting of with some Alloy bar in the lathe the piece is turned to correct diameter
and a groove is turned to mark the depth of the fan.
A 5mm hole is drilled through the centre and this is then opened out to accept two
press fitted bearings 9x4x4


 

Edited By David Kenyon 2 on 18/01/2019 20:22:52