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Spider and S-Cam Alignment

OK. So my questions are:

  1. How much slop is there in the spider bolt holes?
    1. It looks like if there is enough slop, I could rotate the spider and align (I hope I hope) the s-cam.
    2. Everything is machined, so where is the S-Cam's "alignment adjustment"?
  2. If I replace the spider, how is the spider aligned with the s-cam support?
  3. Anyone have part number for a replacement spider?


From the album:

S-Cam Repair

  • 27 images
  • 12 image comments

Photo Information for Spider and S-Cam Alignment

Taken with OLYMPUS IMAGING CORP. u1010,S1010

  • 6.6 mm
  • 1/250
  • f f/3.5
  • ISO 80
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Recommended Comments

Wonder if the axle tube is bent, thus making the S cam bracket not line up with mounting surface?

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On 6/5/2017 at 9:00 AM, Freightrain said:

Wonder if the axle tube is bent, thus making the S cam bracket not line up with mounting surface?

Removing the spider was super easy - just loosened the bolts. Checked the S-Cam bore for squareness with the base and it was fine.

So, I'm not thrilled with this idea, but I'm seriously considering:

  1. Replace the 5/8" bolts with 9/16" gr8 - that gives enough rotational slop to allow the s-cam to nicely align.
  2. Drill and ream two 5/8" holes through the spider and backing - top and bottom in picture.
  3. Press in two 5/8" stainless steel dowel pins to keep spider from rotating.

The dowel pins are to keep the spider from rotating because of the bolt slop. Then tighten the hell out of the gr8 9/16" bolts.

What do you guys think?

Dowel Pins.png

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Sounds like a plan.  

I wonder if somewhere along the lines someone mismatched some parts(or the tube is bent?) and thus the out of alignment and the last guy just ran the bolts in and just tightened'r down?  Putting the S cam in a bind?

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