• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.
  • Guest,  We want to wish You and Your Family a Healthy, Happy Thanksgiving! Click the "X" at the top right corner to remove this notice)
  • PLEASE: Read the FORUM RULES BEFORE registering!

4

Rusnok model 70 spindle bearings

3
Like what you see?
Click here to donate to this forum and upgrade your account!
10

jjharley

Iron
Registered Member
Joined
Jan 30, 2017
Messages
8
Likes
2
#1
Hi guys,
Anybody know if the spindle and drive bearings on a Rusnok 70 are a standard bearing (inexpensive).
thinking about doing a replacement, have a little vibration when I hit 5000 rpm.
Also the Rusnok head is mounted on a Benchmaster.
Unit motor was replaced with a variable speed DC motor and controller (2.25HP).
so maybe it's just the drive pulley bearings.

Thanks for any input
 

4gsr

HM Chief Foreman
Staff member
H-M Supporter-Premium Member
Joined
Aug 8, 2011
Messages
4,413
Likes
2,667
#2
Just an WAG, the original one's were probably a class 3 or 5 bearing. The only way to really know is to pull the spindle and remove the bearings and look for the bearing numbers. Depending on the name brand of the bearings, the numbers are generally stamped on the inner or outer face of the bearing. From the number, sometimes, it will indicate the degree of precision. Also pay attention to the arrangement of the bearing, which direction it came off from. A Sharpie is handy here as long as your marks don't get erased from the bearing. And no, I do not have a clue on bearing numbers of these bearings in you Rusnok spindle. You might go over to Vintage Machinery website and look up your brand and see if anything has been posted that could give an idea of what you need. Ken
 

chips&more

Active User
Active Member
Joined
Mar 19, 2014
Messages
2,042
Likes
1,375
#3
So what makes you think it’s a bearing problem when it’s going @ 5K? Man that’s fast! And the bearings are quiet at that speed? Just about any part of the drive train at 5Krpm is a likely suspect for vibration. And the bearings are quiet at that speed? (I’m repeating myself). Maybe stand back for safety reasons when you do that again…Dave
 

jjharley

Iron
Registered Member
Joined
Jan 30, 2017
Messages
8
Likes
2
#4
Thanks for the input will do some more checking on possible bearing #s. Curious about the $ of the set of bearings.
Will play around with the belt tension, might have it too tight.
 

rzbill

The cheapest thing in an airplane is the pilot.
Active Member
Joined
Feb 16, 2017
Messages
114
Likes
138
#5
JJ,
This is my first post on this forum although I have enjoyed reading this site for some time.
I also own a Rusnok 70 head.

5 or so years ago I disassembled the quill and replaced one of the bearings. It really was a non issue. I took it apart, read the bearing number and got one from the local bearing supply house. There were no special markings on the bearing to indicate a class other than common bearing. Since I bought it used, I cannot claim the failed bearing was original from the factory. While my memory of it is weak, I think the bearing I replaced was the one closest to the belt pulley.
 

jjharley

Iron
Registered Member
Joined
Jan 30, 2017
Messages
8
Likes
2
#6
Thanks for the reply.
That's kind of what I am seeing with small vibration in the head casting but nothing in the quill when it's lowered.
But since the quill isn't showing any vibration I will probably hold off on fiddling with it.
Did the quill come apart easy?
Thanks
 

catalytic

Swarf
Registered Member
Joined
Apr 6, 2017
Messages
3
Likes
2
#7
Hi,
Noticed this old thread, and jumped in to say I am finishing up a complete teardown & restoration of a Rusnok 850. I have had the spindle out and have confirmed the bearing numbers both by talking to EM and double checking against my machine. I cannot say whether they are identical for your model 70, but there is a good likelihood that they are.
The upper spindle bearing is a standard WC87503.
The lower spindle bearing is a 5204zz double shielded pre-loaded double row bearing
Both are just ABEC 1. You can get the pair for around $50 from a good MFG (a bit more if you want SKF)

Getting the spindle and bearings out is pretty easy -- you'll just need a flat pin spanner wrench with 1.5" pin distance to undo the spanner nuts at the bottom/underside of the head casting where the spindle comes out and also a 3/4"-2" hook spanner to undo the spline nut that holds the bearings onto the spindle. You probably don't have either tool, but they're cheap or you can make them. All of the nuts to do this are standard (not reverse) direction thread. Obviously, you'll need a press to get the old bearings off/new ones on. Oh, and you may need to undo the uppermost of the 3 bolts that holds the quill downfeed handle onto the quill, as if it pokes through the quill even a little bit it will block the spindle from sliding down/out.

I have done a full writeup on how to do the spindle bearings for myself, and I can share it with you if you PM me.
OH -- one more thing -- are you SURE that it's the spindle bearings causing vibration? There are also two drive bearings (separate from spindle bearings) under the spindle pulley. They are just 6005 bearings -- very standard. Replacing these takes a few more minutes of disassembly compared to the spindle bearings as you have to pull the spindle pulley off, get the main alu. casting off with it, and some other stuff. It's all still pretty easy unless like mine yours are stuck from old grease, in which case it takes some time and kroil.
 
Last edited:

rzbill

The cheapest thing in an airplane is the pilot.
Active Member
Joined
Feb 16, 2017
Messages
114
Likes
138
#8
Hi catalytic,
Thanks for the writeup. It is reminding me of my 70 spindle work from 8 or 10 years ago. The disassembly sounds a lot similar and i'm positive that my repair only included a very common bearing. The 6205 is common as dirt.
 

catalytic

Swarf
Registered Member
Joined
Apr 6, 2017
Messages
3
Likes
2
#9
^^I made a typo -- drive bearings are two 6005 bearings (post edited to correct). Glad you replied, as it made me notice! All of the spindle & drive bearings are pretty common. The only ones on the machine that were odd were the ones in my original motor, which are a 6203 bearing with a 5/8" nonstandard bore. They're still cheap, but somewhat unusual. EM/Rusnok made Rusnoks with at least 2 different models of Dayton motor, so check before taking my word for it.
 
[6]
5 [7]