Just to let you guys know I haven't been loafing. I'm just going to cut to the chase. The process is the same as my others like at the links below but different engine platform. There will eventually be a video at completion. Boss 302 Inline Autolite Carb Intake Manifold | The Home Foundry FE - 351 Cleveland Inline Carb Intake Manifold | The Home Foundry Intake Manifold - 351 Cleveland IR Inline Carbs | The Home Foundry Mercruiser 470 Intake Manifold | The Home Foundry Pattern Construction via CNC Router and Elbow Grease: Need to gate, coat, and cast it. Stay tuned. Best, Kelly
Looking great Kelly! Is there a spot missing coating inside the thermostat (?) housing (?) Seems suspicious by omission in two pictures... Not trying to pick on you or anything
The TStat internals were plugged when it was dipped because the slurry would pool and not drain in its drying position. The internal can be filled after everything else has dried and positioned such that it can drain. Just hadn't coated it yet at the time of the picture. On my Boss 302 version I didn't coat the internal passage. Best, Kelly
Those pictures are just fun to look at. Where the parts mate and the intake passages meet the body are just so well blended. Just curious, what was the total cut time of the 2 pieces in the first photo and what size stepover were you using? This is all still 2in thick stuff still correct?
Each side of each piece was 40-55 minutes. Approximately 190 minutes for all four sides. It was .1 stepover with a .25"D Ball end mill using a single scanline horizontal 3D MOP. These were 180 in/min. Sometimes I run 200 or even 220. These used 4" thick stock but the upper section was prepped at 22" x 13" x 3.375". I surface the stock to thickness because I can't count on the thickness of the faces being flat consistent enough to register accurately between sides. The lower section was prepped at 3" thick. I always center the part on either the x (usually) or y axis and then flip the part about that axis for machining the opposing side. Obviously for parts that aren't symmetric, this matters for the layout geometry but it also means I don't have to worry about part position when I add shrink and I can locate the machining origin as I choose. However, if there are any 2D MOPs, I do need to manually adjust the depth of cut for shrink, especially on thicker parts, because 4" x .013 = .052" which is too great of an error. The z depth happens naturally for 3D surface machining, but I do insure the stock depth encapsulates the part at 101.3% of size. Best, Kelly
200, 220, whatever it takes. lol! Yeah, the setup for flipping has been working very well for you. Glad to see it.
This pattern served as the maiden voyage for my new improved, large resistive electric furnace. Poured it yesterday. As it came out of the sand.... .....and de-gated Now on to heat treat and machining. Best, Kelly
After the converting my large furnace to resistive electric, the electric insert was no longer needed, but that reduced the interior furnace height, and the intake wouldn't fit for heat treating so I made an insulated wire reinforced extension for the furnace. After heat treat, I introduced the casting to my mill machining fixture..... Then it became a fully machined and functioning intake...... So with the carb and some frill it looks like this..........
