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C-121uk

RJ Front Axle measurements help

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Hi the RJ 58 that I recently bought came without a front axle and it would cost a lot of money to import one so I am hoping to make a copy, first of all was the axle made out of solid steel? I am hoping that there may be a member on here that can help me out with some measurements please. Any measurements will be appreciated and if i have to guess some of them then thats ok.

I have included some images of the ideal measurements. Thanks in advance Ewan :)

 

fullsizeoutput_b1d.jpeg

 

fullsizeoutput_b1c.jpeg

 

fullsizeoutput_b1b.jpeg

Edited by C-121uk
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A: 13/16" (I didnt take mine off the RJ to measure, but you're going to stuff 3/4" into that hole so I would drill it a 16th over that)

B: 1"

C: 1 15/16"

D: 3/8"

E: 2 15/16" (will work at 3")

F: 1" o.d. & 3/4" i.d.

G: 1 1/2"

H: 3/4"

I: 4 5/8"

J: 3/4"

K: 15 1/4" (hard to tell with welds covering the actual joint)

Your K and L appear to be the same measurement, but I can tell you that the over all length is 17" and center to center is 15 7/8".

 

Hope this helps.

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5 hours ago, john7 said:

A: 13/16" (I didnt take mine off the RJ to measure, but you're going to stuff 3/4" into that hole so I would drill it a 16th over that)

B: 1"

C: 1 15/16"

D: 3/8"

E: 2 15/16" (will work at 3")

F: 1" o.d. & 3/4" i.d.

G: 1 1/2"

H: 3/4"

I: 4 5/8"

J: 3/4"

K: 15 1/4" (hard to tell with welds covering the actual joint)

Your K and L appear to be the same measurement, but I can tell you that the over all length is 17" and center to center is 15 7/8".

 

Hope this helps.

 

 

Awesome, thank you very much, I only did the K and L because I thought that the stub axles angled out a little and that would be an easy way of telling the angles. 

Once again thanks!

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Whatever those hole sizes are - just keep in mind they need to be fitted closely to a pin to prevent a lot of play in the steering - same goes with the wheel spindles .

Sarge

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Yes, solid steel bar.

1/16" over size for hole "A" seems a bit large to me and may quickly wear the bottoms of the 3/4 stud and the hole in the axle. A few thousandths should do it.

Not saying 1/16 is wrong, just an observation and some thoughts about it.

Maybe use 1 inch OD steel DOM tube with a wall thickness of .120 for "J". This will leave .005 gap for a 3/4" spindle.

I'm no expert so hopefully somebody with more engineering or machining experience will chime in on this. Or, by the looks of that CAD drawing, you may already have that experience.

:twocents-02cents:

 

 

 

 

Untitled.jpg

Edited by wallfish
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There are standards for hole sizes versus cylindrical fits, i.e. close running to free running fits, plus interference fit.  For a 3/4 shaft, here are fit sizes.

 

Close running fit: clearance limits (min/max) .0008 to .0023

Medium running fit:  Clearance limits (min/max) .0016 to .0036

Free running fit:  Clearance limits (min/max) .0025 to .0057

 

For the application I wouldn't go above the medium running fit.  These limits are based on, not only the hole size but the shaft size also.  Measured the shaft size and add the clearance limit to it to size your hole.  For further information, there are ANSI specs that govern cylindrical fits, buy they're basically the same for what I show you, except they're broken down into 4 classes, from class LC5, LC6, LC8 and LC9.

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1 hour ago, T-Mo said:

Medium running fit:  Clearance limits (min/max) .0016 to .0036

Thanks T-Mo. I knew somebody would have the experience. MUCH tighter than I imagined.

Couple of questions.

-Would this tight of a fit allow for grease?

-How would you approach the tube size for the spindles? Since the spindles are .75 would you order .75 ID tube and/or enlarge the hole or lathe the spindle? (Assuming the spindles measure .75 and the tube ID tolerance is under .0036 )

-Does the RPM of the pieces change anything?  

Just curious about this stuff since I only have some backyard engineering experience.

 

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So is it a pin or a bolt holding the axle? We can turn it to an exact fit.. well within a few thou 

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7 hours ago, C-121uk said:

 

 

Awesome, thank you very much, I only did the K and L because I thought that the stub axles angled out a little and that would be an easy way of telling the angles. 

Once again thanks!

Ok, gotcha. I just remeasured and they are definately NOT set at an angle. Well, other than 90 to the axle itself. 

 

Edited by john7
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3 hours ago, T-Mo said:

There are standards for hole sizes versus cylindrical fits, i.e. close running to free running fits, plus interference fit.  For a 3/4 shaft, here are fit sizes.

 

Close running fit: clearance limits (min/max) .0008 to .0023

Medium running fit:  Clearance limits (min/max) .0016 to .0036

Free running fit:  Clearance limits (min/max) .0025 to .0057

 

For the application I wouldn't go above the medium running fit.  These limits are based on, not only the hole size but the shaft size also.  Measured the shaft size and add the clearance limit to it to size your hole.  For further information, there are ANSI specs that govern cylindrical fits, buy they're basically the same for what I show you, except they're broken down into 4 classes, from class LC5, LC6, LC8 and LC9.

Yeah, I got to thinking about this after made that reply. Mine has quite a bit of play.. every bit 1/16". But mine has been wearing from almost 60 years of use. 

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@meadowfield the pin should already be  permanently attached to the frame. The pin was inserted through a hole in the frame then welded from the backside. I'll have a look when I get home but I'd bet it's 3/4" -10 threads. 

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50 minutes ago, john7 said:

Ok, gotcha. I just remeasured and they are definately NOT set at an angle. Well, other than 90 to the axle itself. 

 

 

Thats great, even easier to make.

 

28 minutes ago, john7 said:

@meadowfield the pin should already be  permanently attached to the frame. The pin was inserted through a hole in the frame then welded from the backside. I'll have a look when I get home but I'd bet it's 3/4" -10 threads. 

 

Unfortunately someone has chopped this off and welded a different axle onto the frame so we will be custom making all of the steering/ axle etc. I'll update my rj thread with some more photos. 

 

 

Thanks everyone for your help! :thanks: @john7 @Sarge @wallfish @T-Mo

Edited by C-121uk
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Hi Ewan, here's the measurements I took from Neil's RJ, thought I'd post them here to help other out :thumbs:

 

58b3105256c93_RJFrontAxleRearView.thumb.jpg.45bc29fd5fb292ff6730c9e97347cf63.jpg

 

 

58b31050e1096_RJConnectingRod.thumb.jpg.abdfb8a17819c371f59006305c47f288.jpg

 

 

58b3104e1a242_RJLeftKingpinFrontView.thumb.jpg.ed6d7350b88c683b2a41c4be00a187e3.jpg

 

 

58b3104f94287_LeftKingpin2.thumb.jpg.4bfeeeb574b71567ac4361b78197b452.jpg

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17 hours ago, Stigian said:

Hi Ewan, here's the measurements I took from Neil's RJ, thought I'd post them here to help other out :thumbs:

 

58b3105256c93_RJFrontAxleRearView.thumb.jpg.45bc29fd5fb292ff6730c9e97347cf63.jpg

 

 

58b31050e1096_RJConnectingRod.thumb.jpg.abdfb8a17819c371f59006305c47f288.jpg

 

 

58b3104e1a242_RJLeftKingpinFrontView.thumb.jpg.ed6d7350b88c683b2a41c4be00a187e3.jpg

 

 

58b3104f94287_LeftKingpin2.thumb.jpg.4bfeeeb574b71567ac4361b78197b452.jpg

 

 

Thanks Ian, unfortunately I didn't have enough time to start this weekend but we now have all of the steel we need :D

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23 hours ago, brians306 said:

nice info thanks

 

Just so you know, they are all accurate, I know because i've made the full set up from the measurements above and it works awesome! 

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