Engineer with 34+ years of experience, was licensed as a Professional Engineer in the state of Georgia for 25+ years.  Lots of good information given above, so I can only add a little theory to the mix.  In order to minimize bending, you want a high moment of inertia.  In order to resist torsional (twisting) deflection, you want a high polar moment of inertia.  Looking through standard beam tables, it appears that the I-beam as described by the OP is actually known as an S-beam.  The dimensions given are close to those of an S10-35 beam, which is 10 inches tall and weighs 35 lbs per foot.  It has a moment of inertia about the x-axis of Ix = 147 inch^4 and along the y-axis it is Iy = 8.36 inch^4.  The polar moment of inertia for this beam would be the sum of those two quantities, or J = 155.36 in^4.  The square tube has an Ix = 62.27 and Iy = 62.27 and a J = 124.54.  Normally the best shape to resist torsional deflection is circular, i.e. round tubing (that's why driveshafts are round rather than square) but that wasn't one of the options given.  The square tube would normally be better for torsion but since the S-beam is so much larger, in this case it is better than the square tube in bending in one axis and better in torsion.  The S-beam would not be a good choice if the loading is in the y axis.  It all depends on the design and how the structure is loaded.  If you would like to send me a drawing of your power hammer, I would be happy to look at it and give you my suggestions.

An engineer always says that it's the low pressure area that pulls it up. But any kid that stuck his hand outside a window in a moving car can tell, you feel a great amount of pressure under your hand that pushes your hand up.

As an engineer with 34+ years of wind tunnel experience, I have to disagree with part of your statement.  I never say it is the low pressure area that pulls the wing up!     It is the pressure differential between the top and bottom of the wing surface that contributes to lift.  There is also a momentum term that is a result of the wing deflecting/changing the direction of the air moving over it (or "as the wing moves through the air" depending on your point of reference).  The suction peak on the leading edge of the upper wing surface is generally much more pronounced than the pressure peak on the bottom.  I believe the human hand is better at feeling pressure than it is vacuum, but that is just my un-medically-educated guess!

Quote from: 427mach1 on July 10, 2021, 07:02:32 PM

Jay, what material are you using in your 3-D printer?  Before I retired, I had considerable experience with Stratasys/Fortus Titan and MC-900 FDM machines, mostly making aircraft production shop aids and jigs/fixtures.  Polycarbonate was our material of choice most of the time but we had about 6 - 8 materials to choose from.  We would sometimes paint the parts with Featherfill primer; it was thick enough to hide most of the ridges.  I've contacted a former co-worker who is still running the FDM lab at Lockheed Martin to see if Featherfill was effective in sealing the leaks or if he has any suggestions.  I'll let you know what he says if you are interested.

I would be interested in what he says, thanks.  I also have Featherfill on hand here.  I don't know how it will respond to fuel, that would be the only concern.

My printer uses PLA filament (Poly Lactic Acid).

Well, I'm not going to be able to help you much.  He said the best way to make a leak-free manifold would involve a machine other than a typical 3D printer.  It would require an SLS (selective laser sintering) machine with Nylon-CF as the material.  Another option would be an SLA (stereolithography) with a high temp material.  I would suggest you call your printer manufacturer and see what they say about sealing but can suggest a few things for you to look into.

We used a Devcon 2-part epoxy called Plastic Welder to glue large parts together.  This stuff might work to fill any larger voids, cracks, etc. that you might have.  It might also work as a sealer but that would involve a lot of work, especially inside the plenum and ports.  I'm not familiar with PLA so you would need to check compatability.  I believe Plastic Welder is solvent resistant but it would be worth contacting Devcon to verify.

We used our FDM machines to build a wind tunnel model with built-in surface pressure ports and it was a nightmare trying to leak-check each of the ports due to the porosity of the material.  We could not get a good seal with the suction head.

Edit:  I've asked my former co-worker if he can suggest anything to seal an existing part (rather than build it with another machine/method).  Still waiting for his reply.

All I have been able to find are the case dimensions:

https://www.charlietranny.com/FordomaticID.htm

What manufacturers have you checked?  How about Wheel Vintiques? 

https://www.wheelvintiques.com/wheels/classic/o-e-chevy-ford-bare-finish.html

Yes, that would be over the first year Mustang.   Here is a list of curb weights for each Mustang body through the years.  https://www.cjponyparts.com/resources/mustang-curb-weights

Send them to someone who has a CNC program for porting Edelbrock heads.

S&W M&P 9mm with an Apex aluminum trigger and short reset sear kit is my most accurate centerfire handgun.  My Ruger Redhawk 41 magnum is another favorite along with my S&W 4013TSW 40 caliber.  Favorite rifles are my Savage Model 12VLP in .204 Ruger caliber; 8.5-25x50 Leupold, and my Winchester 70 7mm Rem Mag with a Leupold 4.5-14x40.  Both of these scopes have the CDS (custom dial system) that are matched to my handloads.