5 Cylinder radial (winter's project)

[metalmad]

Fantastic start George :bow: :bow:
Pete

 

[gbritnell]

Hi Peter,
I have both a horizontal/vertical rotary table and the dividing head that you see. My rotary table is an 8" so when it stands up it's quite high. I use the dividing head for most jobs. I have the same dividing head that you have pictured. They have a threaded nose on them for mounting the face plate. I made an adapter up to mount my set-true chuck.
I use a center drill to start every hole. I have never relied on the drill starting in the right spot. To locate my holes I use the coordinate method. From the center of the bore I move to the proper locations to put the holes in. On this particular engine it would be a pain to relocate every cylinder hole to put the mounting holes in.
Hi Marcus,
When this question came up in another thread it go me thinking about this engine so I did a layout and found that the locations weren't where they needed to be so I repositioned them to get the proper stroke and piston position using the same slave rods dimensions.

 

[steamer]

Looking great George! Off to a flying start!
:bow:
Dave

 

[gbritnell]

Ok, with all the basic machining complete it was time to start on the nose radius. To do that I made a step-off chart using a .187 dia. ball mill. The first thing I did was to blue up the lifter pads with a marker pen and I then made a template up to scribe the outline of the pad.

 

[gbritnell]

With the starting point established from the already cut radius on the nose I started the step-off process. The first picture is the first cut. The second picture is the progression up the radius. The third picture is shows the initial steps between the layed out pads. The fourth picture has the nose radius running all the way to the cylinder pads between the lifter bosses.

 

[gbritnell]

The next picture show the crankcase as it came off the mill. The steps look big in the picture but you have to realize how small this piece is. When I calculated the steps the cusp between steps was only .0007. The part was again blued up and the first stages of finishing were started, first with a small burr and files to get some of the high spots down.

 

[metalmad]

Awesome :bow:

 

[gbritnell]

With a lot of stoning, filing and polishing the crankcase is almost done. In the first picture you can see the oil sump cavity. In the second is the pad that was left between the 2 upper cylinders to pipe the oil supply. To the left you see the other area between the cylinder pads. This was cut with a .312 ball mill. The lifter bosses are extended so a set screw can be put in to hold the roller lifter in the proper orientation. The original Morton just had round nosed lifters riding against the cam gear. All that remains it to tap a whole bunch of holes, 0-80, 1-72 and 2-56.
gbritnell

 

[steamer]

I always love watching you whittle.....NICE!

:bow:
Dave

 

[stevehuckss396]

About how long did you spend on the piece G. Was this all in one day?

 

[mklotz]

Whenever I see some of George's incremental profiling as shown here, I think of those crazy people who claim that the Egyptians must have had help from extraterrestrials to build the pyramids with such precision. Their comments are an insult to what the human mind and hand can achieve with sufficient intelligence, dedication and patience.

Good onya, George. I'd say more but I have to go out in the garage now and sledge hammer my mill into foundry-sized chunks.

 

[tattoomike68]

Whenever I see some of George's incremental profiling as shown here, I think of those crazy people who claim that the Egyptians must have had help from extraterrestrials to build the pyramids with such precision. Their comments are an insult to what the human mind and hand can achieve with sufficient intelligence, dedication and patience.

Good onya, George. I'd say more but I have to go out in the garage now and sledge hammer my mill into foundry-sized chunks.

Beat it into a round toit.

[ame]http://www.youtube.com/watch?v=pxeswltvhLA[/ame]

 

[gbritnell]

High Steve,
I have about 10 hours in this piece. I got the machine work done in one day, 7 hours or so. The second day I did the hand work and tapped the holes. The Autocad is really nice for laying out bolt holes and setting up radial step charts for round surfaces. Once you have your centers and starting points it's just a matter of reading the digitals and moving to the right spot. Oh yeah, and remembering which step you last made.
George

 

[jpeter]

I find it hard to imagine the old timers having enough time in their lifetime to do this kind of machining. Think about planning all the steps without Autocad. My computer screen is only 3 feet away from my mill and I'm constantly referring it.

 

[ref1ection]

I get distracted for a couple of weeks and look what I come back to. Amazing work again but at this rate you'll be looking for something to do after the new year.

Ray

 

[petertha]

Wow, you sure make progress!
Whats your plan for mounting the cylinder jugs? I see 6 threaded? holes on the top face but looks like only 2 coming through the crankcase itself. And the sinle hole that is entering the cyclinder bore perpendicular, I assume thats just over-drill related to mounting holes for the back-plate or something?

 

[gbritnell]

Hi Peter,
The 6 mounting holes are all the same depth. It's just that the 2 (front and rear) are drilled through a narrower section. I couldn't go through with the others because they would interfere with the oil sump or the pressure feed area. The holes from the back are for mounting the rear crankcase cover.
George

 

[kvom]

I was wondering how that nose would be done when I saw the drawing a while back. Very impressive.

 

[petertha]

This engine will have a double oil pump, feed and scavenge, to lubricate everything. It will be driven off the rear of the crank along with the distributor.

Sorry to jump ahead, but now you have me re-mulling my own (oil pump-less, glow ignition, oil+methanol premix) design. I think the Edwards 5 employs an oil pump system similar to what you refer to ven though it runs straight (non or low oil) methanol fuel on glow vs gasoline?

Whats your plan in this regard? The pump feeds high press oil through the crankshaft center, then into the master-rod (crankpin) bearing? Do the link rods & wristpins see this flow circuit somehow? And spent oil then collects into the bottom sump are you refer to? Does this system therefore require some sort of pressure regulator or bypass loop? Man, this will be neat to see unveiled!

 

[gbritnell]

Hi Peter,
I have a 2 stage oil pump designed. It will take oil from a remote tank and pump it into the crankcase, thereby feeding the rods, cam and drive gears for the cam. The crank will run on sealed ball bearings. At the bottom center will be the sump for the return oil. This will go back to the other side of the pump and then back to the oil tank. The only thing I'm not sure of at this point is whether to make the return side pump a little bit bigger (one tooth more on the gear), that way it will always be ahead of the oil supply.
The sump is connected internally through the case and inner cover. There will be a line back to the tank from this pump. The feed line will go from the tank to the pressure side of the pump and then a hard line will take the oil up between cylinders #1 & #5.
I have gears on the back side of the crank (in the fuel chamber) that will drive the oil pumps and the distibutor bevel gears. I plan on using a small amount of oil in the fuel (50:1) to oil these gears (3). The bevel gears will be in their own pocket and will be coated with light grease.
George