I found a VN12

Cal,

Thank you for the time and brainshare. I'm away from the shop now (earning a living to feed my habits).

The R8s would not "seat" well - I do not think they are resting on the taper - note how far the R8 sticks out.

The C "clicked" in and it was obviously resting on the taper.

I need to spend some real time with a good internal mic (or at least a non-floopy set of dividers) when I get home. I am not sure what I am dealing with yet.

I would take you up the manual - it sounds more specific to my machine than what I am using.

As for my cutter head - it is turning fine - but it won't move to the left. I will try blocking up to the table next weekend.

Thank you again,
Devon
 
The manual has been sent.

Make sure you check the depth of the bore. R8 collets are a bit longer than a 'C' collet. You don't want the tail end of the collet able to wiggle around. I'm thinking that you will want some sort of sleeve for use with 'C' collets (and I would ditch the R8s).

One problem here is that Van Norman spindles are not hardened all the way through, so when you bore one out you have soft area in contact with the collet. Unless the bubba that did this heat treated the spindle to harden the new bore, you've got a bit of a problem...

Cal
 
Thank you for the manual, Cal. I have the cutter head off now. I just needed a bit of "tapping" with a dead blow top and bottom.

But, the taper is VN C all the way. Yet the spindle has been bored out to R8 size.

My options:

1. Try to grind out existing spindle to a more true R8. I have never ground this way and I may be unequal to the task - but there is enough meat to try it for sure.
2. Send the spindle out to have spindle ground to R8.
3. See what a new spindle (VN PN: 12-756) might cost to make in C (5V).
4. See what a new spindle might cost to make in R8.
5. Try to find a part from RPI (called Gene last week - not looking great).
6. Make a collar/adapter for the shaft of the collet and run 5V (per Cal below).
7. Fab-up a special R8/5V crossbreed TTS or Royal toolholder adapter just for this mill.


I can probably turn the work part way down for 3 and 4 on my Clausing (stuck at 900 RPM due to Vari Drive failure) and send the part out to be hardened and ground.

The downside to R8 is that it is not as rigid for Horz work (they say). But I can easily fix this with some kind of "soft" blocks in the 1/2 slots between my spindle nose and my CUSTOM made Horz mill bars (note: these bars are fictional at this time so they can have all sorts of features).

I have some Tormeck Tooling System stuff from a horse trade 3 years ago - and I did some measuring. I would be giving up some precious Vert space with a tool system "in the middle" I think.

I suspect 3 and 4 (making new spindles) are going too pricey to contemplate - $600 to $1000 in metal and labor most likely - unless I do some of the work here first.

Please let me know if you think of anything else - or a reason why one of these is a TERRIBLE idea.

Thank you all!
 
Devon,

First of all, before you take the spindle apart, you need to carefully measure and mark the current position of the nut that holds the ring gear in position along the length of the spindle. This is because it's critical to put it back in the same position so that it meshes correctly with the pinon gear. Put witness marks on the gear, nut and spindle (you can use the keyway in the spindle as one of the witness marks). Count the number of exposed threads on the spindle and measure the distance from the nut to some convenient surface on the casting.

Van Norman spindles are not hardened all the way through, so any grinding, etc., should be followed by heat treating and final grinding. Not cheap. Plus what do you do if the spindle warps during heat treat?

Personally, I would sleeve the spindle back to 'C' using something like 4140 HT (pre-hardened). You should be able to bore the sleeve right in the spindle using a boring head locked to the table in some fashion. You can buy a set of 5V/C collets and endmill holders from http://www.tools4cheap.net/ for less than you will spend doing a proper conversion to R8. If you convert to R8 you close the door on using VN accessories like the slotter and high speed universal head, should one come your way.

When they did this half-a$$ed conversion, did they add a key for the R8 collets?

Cal
 
Cal Haines said:
When they did this half-a$$ed conversion, did they add a key for the R8 collets?

Cal
Click to expand...

Cal,

Thanks again. I was wondering about those safety-wired nuts around the bore. I will witness all and maybe supplement with some High Rez photographs - before (if) I take it apart.

As for the R8 key - nope. This is why I was dreaming up some kind of R8 "mill dog" situation to supplement R8 friction alone for Horz work.

The positive "renewal" news is that the handweels, the arbor support, cutter head door, etc have been stripped, ultrasonic cleaned and sit awaiting paint (cleaner than they have ever been).
I pulled 1 chip of the 6 coats of paint (saftey blue, yellow, white, grey, light grey, green) and I did a little computer "amalgamation" by sampling the chips and averaging the result. The result was about "pea green". This is my new target mill color by way homage to the mill's past.

The new bad news is as follows:
1. I thought I had 4 perfect handweels - not so. One of them was welded (or silver braised?) in the middle of one spoke. A great grinding and painting job was done - but so great a weld as it has a hairline crack in the middle. They probably did not heat the area enough or grind down far enough before fixing. This I CAN fix.
2. I have not started on the electric yet, but I opened the box to pull some wires out (for a 110 lamp). I have a sneaking suspicion that my 1ph motor was simply a 3ph that some guy was running on 1ph. I feel just a tad sick to my stomach when I think about this so the electrical will wait for another day. I have both RFC (may shop has a 5hp RFC) and various VFD solutions tucked into Listas and cardboard boxes in the corners of the shop. So really, its a resale hit if 3ph. But I don't plan to sell.

I'm going out for Chinese food if I can get my hands clean...
 
Shopsweeper said:
...
I pulled 1 chip of the 6 coats of paint (saftey blue, yellow, white, grey, light grey, green) and I did a little computer "amalgamation" by sampling the chips and averaging the result. The result was about "pea green". This is my new target mill color by way homage to the mill's past.
...
Click to expand...
That sir, is WAAAAY over the top. :rocker:



Shopsweeper said:
2. I have not started on the electric yet, ... I have a sneaking suspicion that my 1ph motor was simply a 3ph that some guy was running on 1ph. ...
Click to expand...

I'm working on a low-motor No. 12 with a single phase motors. Check the tags on the feed and main motors to be sure.

Cal
 
If its warm next weekend I will paint the arbor support as a test and post a pic. I'm going to call the color "edamame", but it looks awfully pea green to me.

I cannot abide the Forest Green from the factory. And my shop has enough gray in it already. White gets dirty too easy. Pea Green may be the ticket.

Talked to Keith at Total Shop Services in VA on the phone today (the man was at work on a Sat!). He's willing to tackle my spindle if I end up sending it out. I wonder if I should ship him the whole cutterhead - that way he can factor the bearings, etc on the R8 re-re-grind job. I have a friend up in Tulsa who is willing to do the job after hours at his workplace for favors and tacos - But I found Total Shop Services by looking for shops that do lots of spindle work for happy customers. What is the point of putting Time and TLC into a machine that is "sort of" accurate?
 
Shopsweeper said:
...
Talked to Keith at Total Shop Services in VA on the phone today (the man was at work on a Sat!). He's willing to tackle my spindle if I end up sending it out. I wonder if I should ship him the whole cutterhead - that way he can factor the bearings, etc on the R8 re-re-grind job. I have a friend up in Tulsa who is willing to do the job after hours at his workplace for favors and tacos - But I found Total Shop Services by looking for shops that do lots of spindle work for happy customers. What is the point of putting Time and TLC into a machine that is "sort of" accurate?
Click to expand...
Did he give you an idea what it would cost? What did he have to say about heat treating it?

Cal
 
Cal Haines said:
Did he give you an idea what it would cost? What did he have to say about heat treating it?

Cal
Click to expand...

The approx cost would be between 400 to 1600 depending on lots of factors. Simple regrind on the low end to new spindle on the high end. He did say that they ground out some of these for a large production company a while back so he is familiar with the VN setup.

The problem, of course, is that 1600 is a lot more than I have in the machine right now. This is normally the problem with seeking out "the best" - they get remunerated highly. I'm going to talk with a place here in Tulsa and one in Fort Smith, AR this week about the work. I just don't want to send it to any job shop around.

I am seriously considering pulling the spindle and whipping up a CAD version in Alibre and shopping just THAT part around to some internet CNC job shops. I figure I can pull the IDs from the specs of the 5V tooling and the ODs should be measurable (the nose is 2.125 inches on the dot).

This would let me compare fab jobs to regrind jobs dollar to dollar. I approach decisions like and old dog lays down - I circle around a few times first. :)

My consulting Tool and Die Maker (dad) says that I should STILL do the final few thou ON the mill to eliminate run-out on any new spindle.

We did not talk heat treat for long enough - I still don't know what his low end plan would get me - likely a soft spindle.
 
I like the idea of getting some bids on the spindle. You could probably sell a few of to help with your costs. I can help you with any missing dimensions. Can Alibre export a DWG file?

But I really, REALLY, REALLY want to discourage you from going the R8 route. All that's going to buy you is less expensive collets. But you give up the strength of the drive dogs for C/5V end-mill holders, shell mill holders and arbors (unless you want to invent your own R8/C-dog tooling system, in which case you're not going to come out ahead on the collet savings anyway). And, as mentioned before, you won't be able to use Van Norman accessory heads There's absolutely nothing wrong with the C collet system. Sure, it has a slightly smaller capacity than R8, but you have no business using big end mills in a collet anyway. Get a set of end mil holders and thank me later.

Don't even consider a regrind of the spindle that doesn't include rough grind, heat treat and finish grind, otherwise you're wasting your money. As your dad said, the finish grind should be done in the cutter head using it's bearings (no need to grind it on the machine since it's easy to send out the head). A proper job would probably include building up the sections of the spindle where the bearings sit by either welding or hard chrome and then grinding them true after heat treating.

Since you've got a tool and die maker to help you, why not sleeve and bore the "damaged" part of the spindle back to 'C'. Maybe he can help you hone it on the machine? The taper is the most important part as far as aligning the collet or arbor anyway and that's apparently intact. You could also look for shops that have a Sunnen hone and can hone your sleeve true and to size once you have it rough turned.

Cal
 
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