This is probably my best combination of CAD, CAM, lost foam casting, and casting machining to date. I suppose I could throw automotive induction theory in there too. It’s basically a 351 Cleveland Inline Autolite Carburetor Intake Manifold but it’s designed to fit Jay Brown’s FE Ford Series intake adapter. For those of you that know Ford FE engines, the pushrods run through the intake manifold, as did the coolant circuit and distributor, so any time you wanted to get at the lifters, you had to remove the intake which also meant you needed to remove the distributor, push rods, and break the coolant circuit. The adapter uses modified 351c intake manifolds as a dry intake and allows access to the lifter valley with everything else staying intact and in place. -Pretty slick set up for an FE engine. The pattern pieces were fairly straight forward except the central pieces (runners and carb plenum). It really stretched me in my CAD skills but I learned a lot and as a result am now to the point where I’m pretty comfortable with Alibre CAD. David, you were right, Alibre is great value for money. I’m running v27 Design Professional. Those two pattern center pieces had a lot of functional constraints that included equal runner length, 20% taper in runner cross sectional area, defined plenum volume, carb positioning to accommodate stock distributor location, and provide adequate hood clearance. It requires two-sided, 3D stepover ball nose, CNC machining, of two, 24” x 12” x 3” inch XPS blocks. 3” depth of cut on 3” high stock is at the absolute Z-limit of what I can do with my existing CNC machine (or so I thought!). I used CamBam for CAM. During the CAD design work, I had to add some holding tabs to the 3D model to hold the pattern in the machining frame while being cut by the CNC Router. There is a command function for doing this in CamBam for 2D/2.5D machining, but in 3D, I must import those features. CamBam seems to like .stl files for surfaces so I export the solids as such. There were a variety of other mods to the parting lines and machining frame I had to incorporate for easier CAM programming and machining. I use Camotics as a simulation program to test the g-code files and observe results and run times. Without simulation, I’d waste a ton of time and have a big pile of scrap foam. This all would have been an easier task with the new CNC Router I’m building (sighhh…., it’s coming but until then the show must go on!). Nearly all the machining was done with a single ¼” ball nose bit. It’s a lot of surface area and took about 90 minutes/side for each of the plenum/runner halves. I could have gotten some time out if I did the roughing with a bigger bit, but just being able to turn it on and let it run from start to completion without a tool change was worth more to me than a few minutes of run time. I’d rather clean the shop while it runs….because it needs it! The other pieces were a combination of 2.5D and 3D CNC machining but comparatively straightforward to model and machine. So four pieces assemble into lower intake manifold, and the fifth bolts on as the Inline Carb adapter and there will be four versions of that last adapter casting. This modular approach to the pattern is versatile and easy to adapt to other intakes and allows me to re-use many of the pieces and programming saving a lot of time on future projects. So a little gluing and Assembly Fixture Work Then some sanding and detailing…. This is where I wanted to get to some 7 years ago when I started home metal casting……basically cast whatever I could dream up, and it took CAD and CAM to translate imagination into lost foam casting patterns, and evaporative pattern casting to get there. I can still remember on Alloy Avenue when I showed up as a total greenhorn with an A60 crucible, and Cast Iron Gypsy said oh my God, you are going to hurt (Kill!) yourself, tell me you have a crane, a pouring pit, or just start smaller. –….And thankfully I did & years later and a lot of shop-built foundry equipment since, here I am! Here's sneak peek video of the finished pattern. You saw it here first! Best, Kelly
Had good weather Tuesday so I got after it. Gating attached..... Molded….. Demolded.... I didn’t quench this casting. Just let it cool and as usual used compressed air to blow off the refractory coating..... …and oh happy day! There is still 4lbs of gating and 1lb of machine stock on there so the casting will weigh ~11.5lbs…..pretty happy with that. Will get heat treated and then on to machining. Best, Kelly
Got the patterns for the four versions of the carb adapters made and gated. Also dip coated them. Hoping for good weather and to have a small casting session day after tomorrow. Best, Kelly
After some time on the mill........ I got it finished up..... The intake only weighs 9.5 lbs and the lid a little less than 1.5 lbs. That's super light for a cast intake manifold. The wall thickness is 3/16-1/4" except for the flanges which were cast a little over 1/2" thick and machined to 3/8". I'll be putting a video together. Best, Kelly
I'll have a video of the completed ready to run system in the not too distant future. Here's the intake project. Best, Kelly
Got this one wrapped up. Here’s the completed system........ ......and the wrap up video on the finished system. Video still uploading....be patient. Fuel log casting project here: Carburetor Fuel Log | The Home Foundry Drop base air filter here: https://forums.thehomefoundry.org/index.php?threads/automotive-oval-air-filter.894/page-3#post-51233 Best, Kelly
