Art & Inspiration FORDILLAC FLATHEAD IN 1/3 SCALE

With all the necessary machining done from a flat surface it was time to do the angled parting surfaces.
A center line was scribed on each part and they were then mounted to the angle table. The table was rough set to the proper angle and then it was checked with a dial indicator using trig to get the angle perfect. Hopefully when all the machining is done the bosses will touch the inside of the upper cavity at the same time the angled surfaces fit together.
The layout line was picked up with a wiggler and the -0- set on the digital readout. A cutter was mounted and the table was moved by the radius of the cutter. The cutter was then brought into contact with the job until it just nicked the layout line. This would give me a starting reference for the angled milling. The spindle was set to the proper depth and the cutting started.

 

All the angles came out perfectly so the heads were put together with dowels and mounted on the fixture plate to step off the shape of the water outlet bosses.


With some burring, stoning and filing the machine marks were removed and the part sanded smooth.


This is what it looks like from the top side.

 

The heads were mounted on the block for some beauty shots.

 

Can you furnance braise the two parts of the heads together? I understand that the OEMs do this for some prototype aluminum parts.

 

GBRITNELL - you say, " it was time to do the angled parting surfaces", and you go through the machining process, but what "parting angles" are you putting in the heads? The top and bottom of the heads appear to be parallel.

Maybe you can elaborate a little. Otherwise thanks for posting. Neat project.

 

If you look at the pics of the upper and lower being machined you will see the angles surfaces being cut on the ends. In the second to last picture you can see a faint line showing this parting line. It's not the head face or the top of the finned surface but where the 2 pieces bolt together.
When I worked at Ford in the pattern shop we did a special job for engineering. This was to machine a complete head in slabs of aluminum. They would then take the slabs and weld them together using an aluminum sheet material sandwiched between the layers. Apparently the melting temperature of the sheet aluminum was just under the melting temp of the original metal. They used this for quick experimentation of new parts. If they wanted to change an intake runner for example they could just saw the welded head apart, mill off the layers that the runner was in and weld in the new ones. This way everything could be done on a CNC mill and they wouldn't have to build new dies and tooling every time they wanted to change something.

 

gbritnell - Got it. Thanks.

Follow up question: Reason/advantage for the angle? Extra work unless there is a good reason not to have the two halves parallel at the parting line.

 

The roof of the combustion chamber has an angle on it as does the area leading from the valve pockets into the combustion chamber so the angle of the split had to follow these angles. I could have made it straight across but then it would have interfered with the water outlet.

 

Making good progress on the engine. Next up is the timing cover. As I stated, other than the top exit for the exhaust all the other shapes will mimic a Ford flathead. The timing cover started as a block of 6061 aluminum. The back cavity was machined out and the mounting holes were drilled and tapped to mount to the fixture plate for all the other machining. Once the machining is complete the tapped holes will be drilled out to the bolt clearance size.
First up was the distributor boss. A step-off chart was created and then the radial profile was created with a ball end mill. The next step was to rough off metal around the ribs and bosses. Once the heavy stock was gone then it was time to go back and refine all the cuts, going up to the ribs and shapes. The final step was to stand the piece up in the mill vise and with the boring head running in reverse the back side of the distributor neck diameter was brought down to the stepped of shape in the front.

 

The next piece was the bellhousing. The number of hours in the piece is really enormous due to the double stepping of the radial shape of the housing, once to rough the heavy stock off and the second time to refine the shapes.
It started with a piece of 6061 aluminum, 5.75 diameter x 2.125 long. A center was layed out and the part mounted in a four jaw chuck on the lathe. The trans flange hole was put through and then large steps were cut out with the boring bar to simplify the shaping process on the inside.
Once it was roughed the part was clamped to a rotary table and with a step-off chart the inside curvature was cut. Once finished the area around the inside of the clutch housing was milled to shape leaving stock for the metal wall.
As with most of the parts a fixture plate was made to mount the housing for further machining.
Some of the mounting holes were tapped for bolts while a couple of the others were used for dowel pins.
Some layout lines were scribed on the outside to give a rough idea of where to cut but ultimately all the dimensions were cut to the drawing size.
The process for cutting something like this part with so many intersecting shapes it to rough everything staying at least .062 away. Once the general shape starts to take place then the second and third series of cuts are made, here again to the drawing dimensions. The most laborious part is the stepping off of the radial shape. You have to make the steps small enough so that when you get ready to finish there isn't a great amount of stock to come off but large enough so it doesn't take forever to cut. With the outside shape there were 34 steps.

 

Here's a couple of pictures of the assemble pieces to date, block, heads, timing cover and bellhousing.

 

Simply amazing . I can't wait to see the finished product !

 

Beyond my imagination.

 

Your passion for these projects is almost as rewarding to us as to yourself. Your engineering and machining skills are equal to some of our legends.

 

Wow, I am amazed at your skill and ability to produce an engine like this. Can't wait to see the finished product.

 

Hats off to you sir. A TRUE Engineer

 

Wow! This is one of the coolest things I've seen in a long time.

 

The next large piece is the oil pan. This started from a very large block of 6061 aluminum. This is one of those pieces that will have more metal removed than what remains.
The block was squared up on the mill and then drilled out with progressively larger drills to remove some of the stock. Once the drilling was finished I went in with several .50 ball nosed mills to start opening the inner cavity up.

 

Once the cavity was roughed out the intricate job of stepping off all the radii and shapes started. The most complex areas was at the front of the pan where 5 surfaces come together. These would only be cut close because all of the surfaces would have to have 2 degrees cut on them so the process would have to be repeated.







In the rear corner of the pan a pocket for the oil pump was also roughed out.

 

With all the internal surfaces finished it was time to start on the outside. The front area would be the first because of the complex shapes. On the outside there is a radial shape around the front seal area and it would need to be stepped down while rotating the part on the rotary table. A big piece of material was cut of on the bandsaw prior to milling.







The part was then turned so that the rear of the pan could be cut. The seal flange was cut and then the oil pump area was roughed.

 

With the shapes on the two ends milled the remaining stock was cut with the bandsaw and then milled to depth. This pan has three different levels. All the outer walls were then cut to 2 degrees to match the inside and the radii on the edges was cut as close as possible.
From there the remaining stock would all have to be removed by hand using a burr and some files while constantly checking the shape with a radius gauge.
All the hand work was completed and the pan was polished with progressively finer grades of emery cloth.





gbritnell

 

The next piece up is the intake manifold. The original plan was to paint the engine when finished so with that in mind I was going to make the intake out of brass so I could mill the runners and then solder a cover plate over the bottom. As I got closer to starting on this part I really wanted to make it from aluminum but being made from 2 pieces was still an issue. Browsing the net I found an aluminum solder made by Harris (the torch people). This solder melts at 450 and it uses a flux that turns brown when the base metal has reached the proper temperature.
I figured I'd give it a try.
I started by squaring up a piece of 6061 aluminum and scribing some layout lines on it.
The runners would be first so I set up an angle milling table and plunged cut the angular ends of the runners with a ball nosed mill.
The part was then put back in the vise to complete the runners.

 

The next step was to start roughing out the outside shape so the part was put back in the vise at 90 degrees and the area around the runners was cut to size.

 

The part was then put back in the vise to start sculpting the outside shapes. At first everything was roughed leaving .02 on each wall until there was enough shape to visualize all the intersection points. Once the roughing was complete most of the shapes were cut to the finished dimensions.

 

The next step was to set the angle table back up to cut the angled walls over the outside edges of the runners.

 

Now came the time consuming work, stepping off around the fuel pump pad, the breathe neck boss and the generator bracket. This involved multiple setups and tooling changes to get the shapes roughed in without going to far and leaving a gouge that would be unfixable.

 

The plan for the manifold is to make it look like a dual plane type but in reality it will only be a single plane but with only 4 cylinders being fed from each carb. That way I could shorten the total runner length and possibly starve the end cylinders.
More shapes were cut and radii stepped off on the corners of the main runners.

 

With all the milling complete it was time to start all the hand work. First up were small burrs in a flex shaft to whittle away excess material. Next up would be small mounted stones followed by a ton of hand filing using regular and riffer files (die makers files). All the corners needed to be radiused and blended into each other. Stepped off shapes needed to smoothed out and then finally polishing with different grades of emery cloth.

 

All that remained as far as machining goes was to make the cover plates for the runners. The runners had been machined 'to the numbers' when they were cut so a quick dimensional check showed they were within .001 of each other.
Some stock was milled up and the cover plates were milled from it. Once they were cut out hand filling took them down to the finished size so that everything was a nice snug fit into the runner cavities. The ends were radiused to match the elliptical shape of the ports in the top of the block.

 

Oh man, this is crazy!
Crazy awesome! Looking forward to some more updates!