Model A axle dimensions help

Hello HAMBers,

I have been trying to create a "hotrod visualisation" program where you can input the amount of chop, ride height drop, rake etc and see the end result in 3D.

To start with I was collecting dimensions from the web for a standard Model A front axle, (I'm trying to draw the whole car) but I would like some confirmation of the dimensions I found before I draw the axle in 3D.

Dimensions:

ORIGINAL AXLE MEASUREMENTS 50-1/2" Kingpin Center to Center
36-1/2" Spring Perch Center to Center
2-1/4" Tall Spring Perch Boss
1" Factory Drop - measured from bottom of centre of axle to bottom of spindle boss.
.8125 dia. Kingpin hole
Kingpin holes slant 7 degrees inwards
2-3/8" Tall Kingpin Boss
Axle thickness (front to back) = 1 3/8", 1 1/2" at wishbone mounts
The thickness of the top and bottom web of the I beam is about .187 on the outside and about .320 in the centre

Could someone please help me out and confirm those dimensions?

I still need to find out the diameter of the spring perch holes, are they 5/8"?
and if the spring perch holes are straight up and down or if they have an inwards slant like the kingpin holes.

I plan to put the 3D models up when they are done so other people can use them too.

Any help would be much appreciated,
Fletty

 

Most of that is close ... I think

Perch holes are ..........11/16" .... yes slant in
Kingpin holes are .......13/16"

 

I think there might be a 3d file in the hamb archive for the front axle.

 

Perch holes are perpendicular to arc of the axle I believe.

I could extrapolate that and draw it up full size to find the angle and radius or get you the tangent points and you could just bend your lines in auto cad and come close ?

 

Thanks guys for your replies,

31 Vicky. I extrapolated the circle and found that the spring perch holes are on a 4 degree angle.

OJ. Thanks for the tip. I had a look for files on the forum and found some files for a model A spindle and some other good stuff, but no model A axle.

296 V8. Also thanks for the dimensions.

I have drawn up a first rendition of the axle and put it up on my google site here if you want to use it:

https://sites.google.com/site/flettandrew/home/engineering-plans

I'll post a picture up tomorrow of it when I get some time.

Fletty.

 

Below is an image of the axle I drew.



It still needs a bit of work, the kingpin bosses are too large, I think they need to be the thickness of the axle at 1 3/8" ? they also have I beam bits at the tops and the bottoms.

Also need to draw in the kingpin lock bolt holes off centre to the kingpin.

Any idea how far off centre to the kingpin hole centre that is?

 

Yes, i went to the cad library after posting. I recall starting to do one and must never have finished it. I remember making the measurements and starting the drawing but the computer i was working on took a shit and i've lost all that stuff.

 

Thanks guys for the replies,

I have added to the model, adding detail to make it look more like an I beam.




Can anybody tell me what diameter the king pin locking bolt hole is?

and also how far the centre of the locking bolt hole is from the kingpin hole centre?

 

Hope the above helps........

 

The lock pin holes are 9/16” …. they cut into the kingpin bores maybe 3/16 or a ¼ …. hard to tell

 

Thanks 296 V8,

Those dimensions helped me complete my model of the axle.



I'll chuck it up on my website if anyone else wants to use it.

Now for the spindles. I found a spindle that was drawn in CAD previously which is a great help, but I'm sure Ill have more dimensions that need confirmation.

Thanks,
Fletty

 

One other question,

because a 32 axle has the same width between the kingpin bosses and the spring perches, does it have the same arc between the spring perches as a model A?

So if you overlaid the two axles would it look like that below with the 32 axle with 1 & 1/2 more drop?

 

The 32 has the same arc basically
The entire beam is taller / thicker overall by about a 3/8 to 1/2 and the perch bolt area is inset / undercut in top and bottom.
That same area bulges out front and rear

 

Are you sure you saved it in ACAD2004 format? I tried and failed to open it in ACAD2008; says it was created with a more recent version.

 

Ned Ludd - I have put the file back up on the site, it should be autocad 2004,let me know if it doesn't work.

296 V8 - thanks again. So what your saying is that a 32 axle is 2 3/8 in height all the way along (instead of 2" like a Model A) and is milled down to 2" at the perch holes?

And the front to back thickness of a 32 axle is around 1 1/2" instead of 1 3/8" like a Model A?

And the front to back width of the spring perches are around 2" instead of 1 1/2" like a Model A?

 

Works perfectly: thanks. And thanks for a useful resource!