Vn Dividing Head Index Assembly

Reeltor

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Uglydog (Daryl) and I have been discussing how the indexing pin on the VN dividing head is supposed to work. He sent me photos of his assembly; showing that my pin assembly is not fully extending and cannot index into any holes on the index plates.
The index assembly is spring loaded, when you want to turn the pin a number of full turns, you pull on the knurled knob to retract the pin and give it a quarter turn to lock it into the retracted position.

I have a burr or damage inside the assembly and need to take it apart for repair. Any insight on how to accomplish this with the least amount of damage to the assembly would be appreciated.
Here are some photos:
Here you can see the pin partly extended; I think it’s being held up by a burr or damage inside the knob
pin not extending a.JPG pin not extending b.JPG

After some hand work with a file and with the smack of a dead-blow hammer, here is the pin fully extended. This is the goal, to have the pin and body proud of the knob assembly so that the pin will enter into the holes on the dividing plates.
Pin fully engaged.JPG

There is a slot on the inside of the body, I am guessing that this guide pin slides inside the slot. There is something stopping the knob from fully sliding into position. The outline of this pin is only on this side of the knob.

Locator pin on assembly a.jpg

I don't know if there is a limit to the number of photos per post. I'll continue in the next post
 
Locator Pin assembly 2.JPG Second photo of the outline of the "guide pin"


On the knurled section of the knob there appears to be another pin, evidence of this smaller pin can be seen on both sides of the knob. I don’t think it can be one-piece because when you look at the top of the knob you see what looks like the end of the pin itself.

top of assembly.JPG
Here is the top of the knob, This may be the pin

So what do you think? What is the best way to dissemble the index pin assembly in order to clean it up?

Mike
 
Judging from your pics there are possibly 2 pins. I believe one pin retains the knob ( the top one) and the bottom pin engages the slot. Drilling seems to be the only solution as the pins are in blind holes as is the one on my Hardinge. Mine does not have the 1/4 turn locking feature but exhibited the same sort of problem. Luckily mine was just sticking from corrosion and old gunk. Soaking in penetrating oil freed mine up. Are you positive your pin is damaged?

Darrell
 
Darrell,

Thank you for the reply. The pin would only extend a small amount as shown in the first 2 photos. I soaked in solvent in the ultra sonic cleaner for a while with no noticeable improvement. I could see a few burrs on the interior top of the slide and was able to get a small file to smooth some to them out. After seeing the picture of Uglydog's pin and how far it came out of the end; I smacked it with a soft-face hammer; and it moved to the full extended position. But it is still bound up and needs a whack to retract the pin. I can only guess that sometime over the last 60 years someone didn't know about the 1/4 turn lock and bashed it with a BFH, I can see evidence of a prior repair attempt resulting in the break in the cast iron crank handle etc.

I'll throw it in some cleaner and see what happens, it won't hurt. Maybe I filed enough of the burrs off so that it can work and now there is just some crud on the cam-lock sticking things up.

Mike
 
Good luck Mike. Wish I had a easy answer. Worst case scenario is you screw up the slot or something but if you get it apart you will be able to measure and see the pieces. You probably know a guy who could make a new one....right? :eagerness::eagerness::eagerness:

Darrell
 
I wished I'd have picked up on this thread earlier.
I'd have looked at mine closer for ideas.
Randomly, does your pin appear to be straight?
Grease, burrs, or chips? No, you already worked that through.
I'll try to gaze at mine after work Monday.
Meanwhile, I've not found a Van Norman parts break down. But, here is a Cincy parts breakdown. Similar?

Daryl
MN
 

Attachments

  • Cincy Univ Dividing Head.pdf
    25.2 MB · Views: 11
I wished I'd have picked up on this thread earlier.
I'd have looked at mine closer for ideas.
Randomly, does your pin appear to be straight?
Grease, burrs, or chips? No, you already worked that through.
I'll try to gaze at mine after work Monday.
Meanwhile, I've not found a Van Norman parts break down. But, here is a Cincy parts breakdown. Similar?

Daryl
MN

Daryl,

Thanks for the Cincy parts list, I wish we'd find a Van Norman Parts and Instruction booklet like this Cincy.
The Pin is straight, I can see some buggered up part of the slot in the assembly body. I just can't get to it with it assembled. The only thing I found on the VN are these patents sheets.
VAN NORMAN FIG 1 & 2 SHEET 1 US2309241-0.png VAN NORMAN FIG 3 & 4 PAGE 1  US2309241-1.png VAN NORMAN FIG 5,6 & 7 PAGE 2 US2309241-2.png
The cap on the Cincy seems to be held on by a pin, I think I'll drill out the upper pin on the knurled section and see if the top will come off. Yea, I can make a new one, but I kinda wanted to keep it as original as possible.

Mike
 
Please note the attached pics.
Two pins. I took a pic of both sides of the knurled knob.
I believe one is a stop, the other a taper retaining pin.
I didn't take mine apart. Don't know what yours looks like. But, I'd try sliding out the taper pin.
Daryl

IMG_3468.JPG IMG_3470.JPG
 
Daryl,

The knurled section appears to be chrome or nickle plated and so well used that the smaller pin outlines are barley visible. Being a taper pin makes sense, I can't tell which end is larger. I'll flip a coin :grin:
 
On mine one side has the two pins.
The other side has only one.
The side with one appears smaller.
I'd start by tapping the smaller side, read side with only one pin visible.

Daryl
 
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