I'm back at it. This is an open plenum single plane intake manifold for running an Inline Autolite carb on a 1969/1970 Boss 302. It retains the stock thermostat and distributor positions and will fit under the hood of a stock Boss 302 with one of my drop base air filters. http://forums.thehomefoundry.org/index.php?threads/automotive-oval-air-filter.894/page-3#post-51233 Although dimensionally it's quite different, the general shape and process for this project is nearly identical to my previous intake for the FE Ford engine discussed here. FE - 351 Cleveland Inline Carb Intake Manifold | The Home Foundry .....so I won't repeat all that and just cut to the chase on the pattern construction. The biggest difference is this intake manifold has an integral water neck as did the original Boss 302 intake. After some CAD/CAM gymnastics, my CNC router was conscripted into service to make the pieces of the puzzle...... Glue the pieces together.......... Perform some detailing and a lost foam pattern is born..... We have had mild weather all Winter but as fate would have it, supposed to get a foot of snow tonight (go figure), so not sure when I can cast it because I have to use my big rig outdoors and must have clean dry pavement. Guess I'll just have to make some more patterns. Best, Kelly
Uhhhh-boy. Two feet+ of snow on the ground. -11F heading for -19F overnight.......and that ain't windchill boys! Won't be casting with my big rig any time soon that's for sure.....maybe not until Spring . Guess I'll just have to make a boat load of cool patterns and build some machinery........ Best, Kelly
So far, this has been a strange winter, lots of areas have gotten hammered, I'm in Ontario Canada, near the Lake Ontario shore a little west of Niagara Falls and every storm so far has missed me, midway through January and I haven't had to clear my driveway even once, really weird!! BTW, another absolutely amazing foamy, Kelly.
I was in Orchard Park and Mississauga every month for 10 years and would say that is rare indeed! -Enjoy it while you can. Best, Kelly
Got the pattern sprued and gated up. This should be ~<25lb with feed system. I'll angle it as much as I can in the flask but it will be mostly vertical. That hollow water neck is the greatest chance of fail. Best, Kelly
Dry and ready to cast. I just need the February Iowa Winter to cooperate. I placed that muffin fan on top the plenum and covered the rest of the opening to dry the interior. Before I dipped it, I also plugged the openings to the water neck and didn't coat the interior. I knew I was going to have to set it horizontally to dry and it never would have drained from the water passage. I still may coat the interior. Pros and Cons to that, but easy to do now by just plugging filling and then preferentially positioning to drain. As I have said before, these things get very heavy when dipped/coated. The buoyancy forces are large and the risk of breakage (usually of the feed system) is ever present. It also needs to be sensibly supported as it dries to insure the pattern isn't distorted by the weight of the wet slurry. Once dry, the coated pattern becomes much stiffer and stronger. This part would be difficult to brush coat due to the interior features and difficult to reach surfaces but for those of you that don't often lost foam cast, though more laborious, brush coating large parts like this is much safer and practical, and can be done in stages as is convenient. You also don't have to maintain and store a large vat of slurry. Ladling coating onto/over the pattern is also an alternative. Best, Kelly
Three weeks ago it was -15F and 2ft of snow. Since then we've gotten two weeks of nearly 40F and today almost 50F. My driveway was clean and dry and nearly 50 today.......So I declared it casting weather! Put my molding rig to work. I also refreshed my sand so this was brand new silica, slightly coarser than I usually use but wow, did it respond well to vibration and locked everything in TIGHT! Everything prepped and staged.... Demolded....... ....and Yahoo! It came out perfect, even that water neck core/cavity. I can hardly wait to get it heat treated and on the mill. Best, Kelly
Put it on the mill and cut off the remainimg gating. Then back into the furnace for T5 treatment.... Well, I said I could hardly wait... Best, Kelly
Mounted the casting on my fixture and got it machined.... The intake was designed with a raised runner floor..... This was before I machine the flanges to thickness so probably ~14lbs fully machined. ......and assembled into a completed system The video..... Best, Kelly
Impressive as always Kelly! Surprised by how well the sand 'climbed.' What's your guess on total vibratory force in motion here?
Here's the build thread for my molding rig. My New Lost Foam Casting Rig | The Home Foundry I started with one GT-25 on the bottom and four G8s on the sides. The GT-8s are wimpy so I swapped in two more G25s. I can only pull all three of those at full steam for a few minutes before I need to recharge the 80 gallon back to 150 psig, but it seems to do the trick. The turbine vibrators are compact and convenient but air pigs. Best, Kelly
