I am looking for more information on the lower ball joint tapered hole .

What degree is it because 7* degree is too small it appears to fit well at the lower side but theres too much gap on the upper side of the taper.

. I am guessing it could be 10* degrees but then the lower side would be too fat for the hole..

If anyone knows and is certain i will edit the post for future searchers.

 

If you need to know the taper on the ball joint then you're likely doing something very extra curricular. Get some modeling clay and pack the seat, let it dry, remove the clay...... measure.

You could also ask the guy that makes the serviceable ball joint for our arms. He's figured it out already

 

Extra Curricular you bet.

See the problem with that is everyone is so freaking sensitive about sharing "information" when they have a product for sale.

Believe me i been there before when i had my shop I too did the same i don't fall to far from them.
But i am done with the car industry life as a business model altogether. This info is for me and if anyone ever needs to know what degree taper they have.

Especially if you are buying a reamer to clean up a hole, modify, or create your own arms.

Its good info to have. That's definitely not on this forum . If i get the information tonight i will update the post for future searchers,

 

In that case.... would you happen to have a list of the fittings you used for your abs delete kit 😅😅

 

You usually annoy me with your snark, but damn if that wasn't a good counter point.

 

Are you making drop spindles? Because if so, let me help. Been trying to get that done for over a decade. I can probably figure out the lower angle with the spare knuckle I have laying around.

 

Can you use one of those degree finders to figure out the degrees on a stock bj?

 

I haven't examined one up close but is there something about the design that prevents you from measuring the diameter at the top hole, diameter on the opposing side, and distance between top and bottom? If the diameter of the holes reflect the taper, that info would allow you to solve for the angle.

 

I'd expect Mx5/miata people might have the info out there online somewhere if nothing is available to measure, to work out the trig. Think there's only a handful of standard automotive tapers.

 

This is just something that really isn't common knowledge. I think that's why Cr-Rex said this is extra curricular, you're gonna have to figure it out, no one has that info handy.

Even someone that may have figured it out in the past likely forgot what it was by now.

Dale

 

Didn't the NoRotors crew use Pinto ball joint studs? I thought I recalled that on one guy's bump-steer correction thread.

7* and 10* are the standards, I'd be surprised if it's different.

 

That's correct the pinto is the one that is closest to oem and I have it as well now but requires the hole to be reamed with a 7 degree reamer. Yet it is not a direct fit and actually goes on half way. I believe there is a company selling people a kit to convert to heim ends and the stud itself is NOT
how tapered fitment should be. You end up with a gap on the upper side of the hole while the bottom gets snug.

Now i also have purchased both 7 and 10 degree reamers and its neither.
if i was to guess its somewhere between 5-6 degrees. both quality reamers i have purchased cost $100 each so buying reamers
this big for something I don't do repeatedly is a nag for me.


FYI- OEM is smaller than Pinto tapers.
The best I have figured out thus far is using a 7 degree taper and ream slowly so the pinto one has enough taper where it grabs on the spindle yet too much now the top side of the stud has play.

I am still working on this because i would really like to have the correct reamer for the OEM sized taper.
On my personal car I went with the Pinto stud, Reamed it to 1/16 from the bottom of the landing and it will work I just don't like the fact i have a gap on the top side of the stud. Eventually I will get the info on here.


Someone is going to need it especially with the garbage spindles i have seen the past 2 drift knuckles I have done for guys. I am not sure if they used a mallet to bang out the tie rods and butchered the holes circumference. But hey it doesn't surprise me nowadays. The other set of knuckles appears they went crazy with the impact and all it did was spin so it destroyed the inside of the bore.

 

Maybe fill the hole with silly puddy or clay, let it harden and measure it?

 

I think you can just measure the diameter at the top, measure it at the bottom, and the distance between the two (thickness of the metal) to calculate the slop angle no?

 

That’s what I would think too. Those dimensions would get you a right triangle which is definitely measurable. Unless I’m missing something.

 

[D(top) - D(bottom)]/(2 x thickness) = tangent of the taper angle. Then, since it's an angle less than 10 degrees, you can multiply the tangent by 57.3 to get the taper angle in degrees. 57.3 (360/2pi) is the # of degrees in 1 radian. For angles this small, this gives a very accurate approximation of the angle.

 

Probably better off measuring the balljoint taper as that's much longer and less chance of a measurement snafu.......assuming a wishbone sacrifice. Best would be CMM>optical comparator>lathe with dro(or without) to minimize any errors. One of the places I've used that makes custom taps here, also makes reamers. I'd expect the same x 10 fold over there and wouldn't be surprised that the angle is known, if Mazda uses something unique for their cars.