Hot Rods Cast VS Forged axle in an A

Lol. Let’s see….

Best to worst.


B,C,A.

No clue, just like games

 

B, C, A.

 

Well, I guess Budget36 and I are equally smart, (I hope!).

 

A,C,B?

 

Let’s not think of the alternative!

 

I will let this run overnight, to allow more folks to vote.

 

A,B,C.

 

B
A
C

 

Not sure what machining precision can still apply to A or B; I would say.

C A B

 

ACB

 

CAB

 

Been watching this thread so I thought I'd ask Jason at P&J's what their current axle status is. Their most popular width axle is 46 inches and was cast, they've sold thousands. That cast axle has been replaced with a forged axle. They still make their 47.75 axle in cast as they always have. They are making the old Magnum axles for the 37-41 & 42-48 plus the 5 inch dropped I beam axle in cast. That's the latest from P&J's

 

I'm going A B C. My reasons are as follows. Henry was cranking out cars like an old immigrant turning the crank on a sausage machine. Doing that you must have standards that are easily repeated, not sloppy "good enuff" processes. A good dropper starts with a good axle, and if he's off a smidge, well ok. If Speedway finds a hiccup and they're legit trying to hold to a standard they'd reject a miss that big.

If some are now, "WTF Jocko how do you come up with this ****?" it's because of nearly 50 years involved with the finest cars of the industry. Which is more accurate side to side, front to back, etc? A Murphy body fitted to "The World's Finest Motorcar" or a Model A Ford? News flash, the Model A for that standard. Fit and finish easily trumped m*** produced accuracy, and the avg Duesenberg buyer (if there ever will be such) doesn't get out his tape measure, slide rule, bring an engineer, he steps back, pitches a tent in his pants, and pays a sum equal to a dozen Fords for the style, power, mechanical prowess, not to mention status. Does t mean it has to be OMG accurate from one side to the other. Who can tell looking at it? I can't and I do the **** daily. I hope it makes sense.
Ditto on the malaise days. I tubbed enough cars to make up for the ⅝ difference from side to side on nearly every F body and Nova I did. Mopar were worse on some. Who knows an E body fender is ¾ bigger on one side than the other?

I'd still choose forged over cast, the price of admission isn't that much more, and the fun of finding a gennie trump's all of it. **** me that was awful wordy, sorry...

 

I will let you guys decide:

A. Original, unmodified Model A: pin perch holes correct. One kingpin hole 0.087" farther out from the perch hole than the other one.

B. OEM, but dropped by Okie Joe: accurate to 0.003". As close enough to dead-on as I have ever seen an axle. Clearly done in a quality jig, by a talented craftsman.

C. Speedway, with the "advertised defect": perch holes 0.178" farther apart than published specification (this is not a Model A axle). Kingpin holes and perch hole distances match side-to-side. So, this axle is just functionally 0.178" wider than it is supposed to be.

B and C were planar. I did not check A.

KPI was correct to within 0.5º on each.

 

I never measured, but always thought, the perch holes and kingpin holes are parallel? At 8 degrees?

 

I'm not saying that a cast axle will definitely break....but in my shop.

We only install original Henry axles that have been dropped by one of the various axle droppers out there. Period. No exceptions.

 

Makes me feel good my 39 axle is an Okie Joe...

 

I just checked an old Model A dropped axle, looks like it may be a Mor-Drop. The KPI on both ends is 8* checked with an angle finder, but not a precision digital one. KP holes are left- .815 and the wall thickness at front is .272 and .287 rear. Right is .818 , wall thickness .302 front, .325 rear.
The perch holes are both .751 with the left having a wall thickness of .340 front, .352 is rear and the right is at .384 front, .375 rear.
OK, the dropped axle is almost 100 years old, just like a stock one would be. I see the king pin and perch holes being pretty much on the centerline of the forging so I’ll rate a stock and Mor-Drop axle pretty equal, say, A-B with the Speedway coming in at C. From Speedway’s description it sounds like either the KP holes or the perch holes are off the center line by .200.
There’s some forging thickness variation from side to side but Ford got those holes pretty well centered in the forging with old methods.
Is the new axle usable? Sure.

 

Yes to parallel, as seen on my Mor-Drop.

 

@gimpyshotrods I should have read the previous posts before I posted my findings, from Speedway’s description I thought the holes were machined off the C/L.
Could you post pictures of the axle?

 

Sure. I have to deal with the fact that the turbo in the shop truck just fragged, so it might be a day or two.

The holes are all on the same plane, front to back, and on the same line, side to side, just a little farther apart than they should be. The holes on one side are farther from the center line than the other, by 0.178". It is the L/R center line that they are off from, not the F/B center line.

Once ***embled, I am pretty sure that this will not be noticable.

 

I bought one to narrow for the 1933 Ruby and just a quick look as Gimpy mentioned, the king pin hole is towards the outer edge of the boss. Whether it would take wheelstands in a g***er is a concern, but highway use at less than 1000lbs is probably not.