VN12 Spindle Project of 2013

I think the pics were in that exact thread, but I can't see them now.

I am all for a 30 variant - but someone will have to help me with the 30 Spindle ID measurements to feed the CAD.
 
Shopsweeper said:
I think the pics were in that exact thread, but I can't see them now.

I am all for a 30 variant - but someone will have to help me with the 30 Spindle ID measurements to feed the CAD.
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The Van Norman 'C' taper (which Hardinge calls 5V) is well suited to the machine. New collets, Weldon-shank endmill holders and shell mill holders are available from toos4cheap:
If you go with something like NMTB 30 you loose the ability to use one of the Van Norman sub-heads, like the high-speed universal head or the slotter head. There is a host of spindle tooling for the #12 that you can pick up on eBay if you're patient: stub arbors, B&S #5 & #7 tool-holders, MT #1, #2 & #2 tool-holders. boring head arbors, etc., etc. I don't know what's available in 30 taper.

With 30 taper you're probably also looking at changing the overarm support (unless the 30 taper arbor just happens to have the large dead-center in the end for the support).

For collets on a 30-taper machine, you're looking at a separate collet chuck that costs you a couple of inches of vertical working clearance. You've only got 12-1/2" to begin with. So what if the maximum tool you can hold in a C collet is 5/8"? If you need an endmill bigger than 1/2", you should probably be using a Weldon-shank holder or switch to horizontal mode.

I don't think the advantages, if any, of 30 taper are worth what you give up.

If you want to do the Van Norman community a favor, spend your time coming up with some good drawings for horizontal arbors.

Cal
 
Update: Spindle out and on way to Designer this week. That high sulphide oil had everything inside the cutterhead red.

After 90 min in the ultrasonic cleaner, the spindle was still not completely clean.

The Timken class 3 bearing are dated 2/18/43 and 2/23/43 respectively. They cleaned up a lot better after 1 trip though the Ramco bearing degreaser, and 1 trip through the ultrasonic.
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I didn't think to remind you to put witness marks on the ring gear and spindle, and to count the number of threads that are visible on the spindle or measure the gap between the lock ring and the ring gear. It's very important to get the ring gear back where you found it. You also want to put witness marks on any lock rings and mating parts that you have to disassemble.

I hope you were very careful with the bearings. A new set of class 3 bearings is about $500. (Note that the Timken bearing class number has nothing to do with ABEC ratings.)

What bearing numbers do you have? (The cups and cones have different numbers.)

Cal
 
Cal,

You reminded some other person in some other thread with a leaky 16, so no worries. I witnessed, measured and marked everything to death. I even made up an aluminum shim that will help me get the ring positioned right on rebuild (its just a few thou more than 5/32 off the casting teeth side.)

I don't have them in front of me but I think the bearings were 336 and 28150 (Both scratched with a "3" along with the date). My bearings got the royal treatment - dedicated bearing degreaser followed by a medical grade ultrasonic cleaning in beakers full of the good yellow metal and AL friendly cleaning solution just in case.

However, the spindle was badly scratched where it meets the top bearing and both bearings are visibly worn on the face of each roller. I am on site today with the company that owns Dodge Bearings - I wish I knew of a good cross index of part numbers...

All in all, the tear down was uneventful.

I plan to research alternate grease seals tonight - if anyone has any ideas I am all ears. I imagine this problem get solved with UHMW or similar today. what I found inside the head looked like large, worn out, floppy asbestos washers.

I am curious. My machine got "rebuilt" in the 50's by the Burd Company based on a badge that she wears. What kind of rebuilders don't replace bearings?

Cal - I will gladly have a c (5V) Horz Arbor drawn up for posterity as soon as I get my paws on one. I have 2 PEARL scripts scouring flebay and CL at all times and other than about 5 false positives a day due to VN Engine Boring Hardware it has been quiet in the VN C world the last six months.
 
Bearing Update:

I think these are my replacement bearings: 336-3, 28150-3 - $365.92 for both. I knew that Amazon had everything, but Precision bearings is a surprise to me.

I saw some on eBay, but I would prefer a merchant that I can return items without a hassle. I'm out of town today, but I got a line on 2 precision bearing dealers from an Engineer here. I will call around for prices.
 
Shopsweeper said:
Bearing Update:

I think these are my replacement bearings: 336-3, 28150-3 - $365.92 for both. I knew that Amazon had everything, but Precision bearings is a surprise to me.

I saw some on eBay, but I would prefer a merchant that I can return items without a hassle. I'm out of town today, but I got a line on 2 precision bearing dealers from an Engineer here. I will call around for prices.
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Those are the cone (inner race and roller cage) numbers. The corresponding cups (outer race) should be 333 for the front and 28300 for the rear. The front seal should a 9450.

Do you have a copy of the assembly drawing for the 6/12 cutter-head?

It never occurred to me to look for bearing on Amazon. When I was looking for bearings for my No. 16, I found almost nothing in class 3 on eBay. There were a lot of automotive grade bearings, but almost no class 3.

Sharon at Johnson Bearing, in Sparks, NV, was able to find most of the bearings and seals that I needed:
http://www.johnsonbearing.com/home.htm

Cal
 
Not to be a kill-joy...but be careful when buying bearings! You NEED to talk to someone who knows their stuff. I went on the hunt for lathe bearings at one time...also Timken. I'm pretty sure those class 3 are NOT the precision bearings used in machine tools. Class 3 actually are used in automotive applications the Amazon description even mentions it. Timken uses the word "precision" as a matter of advertising, not an indicator of grade. Also, I think the part numbers remain the same, irrespective of the class. IIRC, you need Class 1 bearings, possibly Class 2. Most likely special order.

HOWEVER, if you are knowingly accepting the decrease in precision for economic reasons, then carry on! I know I can't afford super-precision anything....makes me wish I didn't love old machine tools....:roflmao:
 
ScubaSteve said:
... I'm pretty sure those class 3 are NOT the precision bearings used in machine tools. Class 3 actually are used in automotive applications the Amazon description even mentions it. ...
IIRC, you need Class 1 bearings, possibly Class 2. Most likely special order. ...
Click to expand...
Not my first Timken bearing rodeo, my friend.

I'm not sure about the bearing numbers used in a No. 6/12 spindle, but the bearing numbers in a 12/16 spindle are used in lots of truck axles. Maybe that's what they're talking about.

The Timken bearing class number use the ABMA (American Bearing Manufacturer's Association) rating scale. Classes 4 and 2 are "standard" classes. Classes 3, 0, and 00 are "precision" classes. Timken also has a class 000 grade of bearings (at least on paper). The standard bearings don't have the class number marked on them.

Class 4 bearings have a 0.00200" maximum runout and are used for wheel bearings.
Class 2 bearings have a 0.00150" maximum runout and are used for gearboxes.
Class 3 bearings have a 0.00030" maximum runout.
Class 0 bearings have a 0.00015" maximum runout.
Class 000 bearings have 0.00004" max runout.

Note that there is no such thing as a class 1 bearing (at least in Timkin) and that class 3 precision bearings have a fifth the runout of class 2 standard bearings.

Here's a link the the Timken Tapered Roller Bearing Catalog. The runout specs are on page 29.
http://www.timken.com/EN-US/products/Documents/Timken-Tapered-Roller-Bearing-Catalog.pdf

Good luck finding anything better than Class 3 except as old stock.

A standard grade bearing cup and cone will run you about $20 vs $200 for the same bearing in class 3. IRRC, the quote was over $1000 for a class 0 matched cup and cone, and that's with a 6 to 9 month wait. Imagine what a class 000 set would cost...

Cal
 
No offense meant, Cal...just trying to prevent a misguided purchase. You're right....the 0, 00, and 000's seem to be mythical creatures. I've never seen them for sale on any sort of internet site, at least. A class 3 *should* be fine.....but then again, I think it's important to know the max runout before laying down $300+.....
 
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