Ford 4.6L 32V SC Two Piece Intake

Discussion in 'Lost foam casting' started by cojo98v6, Feb 21, 2022.

  1. cojo98v6

    cojo98v6 Copper

    After watching Kelly and all his LF castings of intakes I decided to switch from sand casting to LF myself. Thanks for the wealth of information and giving me the inspiration to dive into LF. I'll have to admit, I thank I'm converted, lol. I do have some fine tuning to get them better, but I'm very happy with my current results. Used the same foam as Kelly and drywall mud. Glued everything together using PVA and hot glue. Then used melted wax to fill in the seams between all the pieces.

    To start with, I had originally made this intake via sand casting with wood patterns, I was never really happy with the casting I got and have been working on and off over the years on a better design. This is a two piece design intake that will allow an Eaton SC found on '03-'04 Cobra Mustangs to fit on the '96-'98 Cobra. Currently there is not intake available to do this, so this is not copied from anything.

    The main intake consumes a brim full A-16 Salamander and comes up a little short as the runners are filled, but the sprue is not. Still got an acceptable casting on my second attempt, first one was a bit short pour not knowing I needed to brim fill the crucible. I just purchased a A-20 to fix this problem, which will also result in a bigger LP furnace, which I've started on, I'll post in the furnace section soon.
    IMG_2559.JPG Here is the result in the short pour, I could probably fix it, but rather just have a good casting.

    Second attempt, usable casting. IMG_2579.JPG IMG_2576.JPG IMG_2517.JPG IMG_2387.JPG

    The top poured good, but the foam bowed a bit, I think it will mill out, but will attempt a second one that hopefully will not have this bow. I cut a piece of Dollar tree foam for the top sealing surface to give it a small boss, this way I would not have to mill the whole top flat, just where the gasket will sit.
    IMG_2575.JPG IMG_2444.JPG
    IMG_2519.JPG IMG_2440.JPG IMG_2438.JPG
    I added a runner across the opening that seamed to make it quite a bit more ridged, so I feel it will work better.

    So how I produced my patterns. To start, I modeled the intake in Solidworks, then created an STL file for 3D printing. Great thing with having it molded in CAD is I can easily scale for the plastic and aluminum shrinkage. Which when poured came out spot on, yay! I printed it in several sections due to size limits of my printer. I then test fitted it to my engine.
    Assem1.JPG Assem2.JPG IMG_2563.JPG IMG_2145.JPG (its only multi colored as I was using up different spools of filament)

    Once I proved I had everything good, I printed router patterns. They are printed with holes for 18ga nails that I use to stick the foam to. I used a 1/4" pattern bit on my router table.

    IMG_2021.JPG IMG_2022.JPG IMG_2406.JPG IMG_2407.JPG IMG_2408.JPG IMG_2410.JPG IMG_2557.JPG IMG_2421.JPG

    Next I will pour the bottom tank section that will get welded to the main intake casting. I decided to go this route as the tank will make milling the intake a bit harder for my mill.

    There are still some parts to come that will complete the whole project, so more to come soon.
     
    Last edited: Feb 22, 2022
    BattyZ, 3Dcasting, Al2O3 and 2 others like this.
  2. Al2O3

    Al2O3 Administrator Staff Member

    Hah! gotcha.......now you're really in for it.......:). I'd seen ya on the site but haven't seen you post for while. Looks like you've been busy........and I like it!

    Sounds familiar. I have my failed intake pour sitting on a 5 gal bucket next to my mill as a constant reminder to me about what not to do.

    The price of poker goes up as the parts get larger. More molten metal to handle, bigger heavier molds, harder to degate and cut up castings. What are you using for a flask and how did you vibrate/pack the mold?

    I do make an effort to keep the patterns flat but I've come to fear this much less. As-cast, my castings are very soft and I can push then around into shape pretty easily. It also means you can pull them out of shape pretty easily when clamping for machining. I use A356 and do heat treat them. It makes a significant difference in strength and machinability with better finished and less tool loading. Do you plan to do so?

    The two major sources I found contributing to pattern deflection are:
    1. The additional weight of wet refractory coating: Larger patterns get so heavy when laden with coating, breakage and deflection can be a real problem. If you dip versus brush, buoyant forces can be a significant problem too. The best way to address the weight of coating is to design drying feet that evenly support the pattern on a flat surface while drying. Coat the bottom side first (if brushing), set it on a flat surface and finish the job. When dry, the patterns get significantly stiffer due to the coating which helps a lot. I often add features to the gating system for stiffness and handling, sometimes glueing on some wooden features that are removed (or sometimes left in place) prior to molding. Formed sheet metal can work too, keep them light, ie aluminum.
    2. Method of molding: Favor vertical positioning and fill and pack evenly keeping the sand depth and resulting pressure equal on each side of the pattern. Vibrate as you fill. It gets progressively more difficult to effectively vibe as the mass of the mold increases. By the time you get to the top of the mold it doesn't have much consequence because the sprue is such a simple feature that doesn't require good packing to remain stable. When I built my flask, I built it so I could tip it to help vibe sand into difficult features. Don't do this unless absolutely no other choice. As the sand shifts, it will not shift evenly and almost always distorts large flat patterns depending on position. Altering the direction of vibration is a better packing strategy.
    That's an interesting take.....3D print the hand guided pattern. Didn't you build a CNC router that could cut the foam pattern directly? Not a big enough cutting envelope for this part? Yep, nails and 1 or 2-sided packaging tape for holding patterns on templates and waste boards.......but can't machine through the tape. The adhesive will instantly load your cutting bit and then the show's over. Machining through glue joints results in the same fate.

    Yes, I barely have enough height under quill and work envelop on my knee mill to machine my intakes. I made an indexable fixture for doing so. I'll post that up in my intake thread in the next couple days. You may have a heck of a time keeping the 2-piece assembly straight during/after welding. Better think that through in regard to preheating or compensating for which way it will want to pull/shrink.

    Great work Cojo!

    Best,
    Kelly
     
  3. cojo98v6

    cojo98v6 Copper

    Been awhile for doing any casting, but I've been lurking in the shadows watching all your posts along with others, learning as much as I can. Your post were a big motivation for me to attempt this and I'm glad I did.

    Using flask very similar to what you are using along with a 20 size air turbine vibrator (ATV), those things work really slick. I have a foot pedal so I can run it as I pour the sand in. I put a couple carriage bolts on the sides so I can attach and detach the ATV to the flask.
    IMG_2445 (2).JPG

    I feel the patterns I have are somewhat ridged, however on the top after the casting issue I noticed I could flex the foam fairly easily, with the added runner it took more effort to flex it, so fingers crossed on the next attempt. Never thought of the weight of the mud causing issues, I'll take note of that next time I apply it. I spray the foam with water/soap mix then lightly put a coat of the mud on and let it dry, then put a second coat. I really need to upgrade to a dip method like you have.
    As far as heat treat, I really had no plan as I do not have the means to do any heat treat as of now. I do dunk the castings right away in water. I've been using old castings to make these as I do not have any ingots of A356. Do you have a source, I've looked online and could not find a source for a home caster, just businesses. Budget casting used to have some as I've bought from them before, but they do not have any on their site now.

    So on that project, short answer, it has a small cutting envelope and would not work for this project. I still have a few things to complete on it as it is not actually done yet. I bought my 3D printer before finishing it and got fully involved in 3D printing all sorts of things. I've actually gone back to working on it and should have it done soon. In parallel to it I started converting my Mill to CNC. I'm just finishing up getting all the ball-screws installed.

    Luckily for the Ford Mod motors the intakes sit flat, both sealing surfaces are on the same plane, so this makes it easy to mill. I like your indexing fixture, may have to apply that to future casting projects. The two pieces of the intake will actually bolt together, I'll just use some gasket sealer, not sure I want to use RTV, was thinking of the Permatex 5131 Anaerobic Flange Sealant. Only the bottom tank will be welded to the main intake, this is why I have the 1.5" coming off the bottom, hoping this keeps some of the heat out of the main casting. On the picture of the printed intake the orange is part of the main intake casting and the green will be the cast tank that will get welded on. I refer to the this as the tank, as the water to air inter-cooler will bolt to the bottom of the supercharger and into the tank. This is how Ford did it on the '03-'04 Cobra's.
    IMG_2596.JPG IMG_2580.JPG

    Thanks for all your feedback.
     
    Last edited: Feb 23, 2022
  4. cojo98v6

    cojo98v6 Copper

    Update!!
    Finally got some time to do some more casting. With the addition of the A20 Salamander crucible I decide to go for gold and cast the lower half of the intake as one piece as to eliminate the need for welding two pieces together. And the the results are....... Success!
    IMG_2952.JPG IMG_2953.JPG IMG_2956.JPG All ready for drywall mud.

    IMG_2991.JPG IMG_2992.JPG Filling the box with sand. I filled it nice and slow with the air turbine vibrator.

    IMG_2998.JPG IMG_2999.JPG IMG_3002.JPG IMG_3003.JPG After cleaning it up with a pressure washer, need to media blast it next, cut the runners off and do some milling.
    IMG_3007.JPG IMG_3008.JPG Ports lined up really good to the gasket, very happy with the the results.

    IMG_3010.JPG IMG_3011.JPG Bought a couple of aftermarket aluminum motorcycle radiators for a honda dirt bike that I'll put together for the water to air intercooler that will attach to the bottom of the super charger.

    In case anyone was curious here is the comparison of the A10, A16, A20 and A55 crucible. The first three are all Salamanders and the largest is a budget one from Legend's.

    IMG_2581.JPG

    Have to give Kelly a big thanks for my success. If it was not for all your post with the wealth of information I likely would not have never tried to tackle this in LF.


    Next is to cast the top part and a idler pulley/tensioner bridge bracket.
     
    Last edited: Jun 5, 2022
    Al2O3 and Meteor Monowatt like this.
  5. Al2O3

    Al2O3 Administrator Staff Member

    Congrats, and nicely done Cojo. You managed that with an A20? Must have been close on shot size!

    Best,
    Kelly
     
  6. cojo98v6

    cojo98v6 Copper

    Thanks.
    This was a complete, filled to the brim A20 casting. I was a bit worried, but it worked out, lol.
     
  7. Al2O3

    Al2O3 Administrator Staff Member

    My Avatar is A60-A20-A10. The price of poker jumps dramatically from A20-A60 with nearly 100lbs of aluminum and crucible alone. The shank probably adds another 25-30lbs

    Salamder Super Cruble Weights.jpg

    How do you plan to handle that A55? Since I work alone, and the pouring heights typical for LF, I built a gantry and hoist.

    Looks like the pattern has a number of laminations. What did you use for glue?

    Best,
    Kelly
     
  8. cojo98v6

    cojo98v6 Copper

    I actually have not used the A55 yet. I started a large gantry crane build for general purpose use along with the intent of lifting the A55. Its about 80% done, just need some support beams added and the electric winch mounted. Its 8ft height and 8ft width. I'm a one man team as well, so I know where you are coming from on this.

    I hear you on the weight, was not sure if I could do a full A20 without assistance, so I loaded it up with as much small pieces as I could to see if I could lift and pour safely before committing to it when full of liquid aluminum.

    I glued the pieces together using PVA glue, I also put a small coating of it on the outside and inside of the layers. I had a hard time trying to keep them all lined up perfectly as the glue was drying. I inspected the area closely after casting and it is a solid one piece no voids. I'll probably just hit it with a flap wheel to blend it together, but that part will never be seen when installed, so I might leave it, undecided.
     
  9. Al2O3

    Al2O3 Administrator Staff Member

    Cojo, a curiosity question since I couldn't see the top of the sprue on the casting, what did you use for a pouring cup?

    Best,
    Kelly
     
  10. cojo98v6

    cojo98v6 Copper

    Right now I'm utilizing your aluminum tape funnel idea. I do plan on making an offset pouring basin as your results look very good.
     
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  11. Al2O3

    Al2O3 Administrator Staff Member

    The foil sprues were an improvement over just a sprue in a cup but the improvements from the offset basin were a pleasant surprise. It sort of depends how much casting you intend to do whether making a reusable one makes sense. For one-time use, you can also just make a mold to make bound sand versions or maybe even PoP if properly dried.

    If you do go the reusable route, I'd recommend using 1/2" thick 2600F ceramic fiber board vs the 2300F because it's somewhat denser and stronger. You may still need some of the moldable ceramic fiber to fillet the corners and occasional patching. Use generous draft....~5 degrees. I'd make the cup capable of holding 20-25% of the typical pour volume. I have three sizes.

    Best,
    Kelly
     

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