Dividing Head for Mill

dickstorer

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Oct 19, 2010
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I have been using the rotary table on my Sherline Mill for making gears but it is not always easy to get it right. For instance what if I needed a gear that has 70 teeth. ____
That is 5.1428 degrees, not easy to get it right. This divider attaches to the cross slide of my mill, it is not perfect but much better that just the rotary table alone. divider.jpg Not sure if I have posted in the right place, Mr. Moderator please move if needed.
 

bruce linde

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i'm interested in hearing what answers you get.

in the meantime, your image is 300 pixels wide... and the system support much much larger. pls always upload the largest possible images and let the system auto-size them for you.
 

NEW65

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Interesting Dick and as Bruce mentions, I am looking forward to hearing more on this one. Good post!
 

Vernon

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Dick,
I believe that the Sherline rotary table with the available computer CNC Rotary Table Indexer – Sherline Products would take care of the calculations like you mentioned. You might call Sherline to confirm. I got to use one in Jerry's class and it is easy to use.
 

dickstorer

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Vernon, I did investigate what Sherline had before I took any action. Their cnc would not be usable on my old model mill. When I talked to their salesman about updating it would have cost far more than the dividing head that I now have. Granted the cnc would have been the best way to go
 

Jerry Kieffer

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Vernon, I did investigate what Sherline had before I took any action. Their cnc would not be usable on my old model mill. When I talked to their salesman about updating it would have cost far more than the dividing head that I now have. Granted the cnc would have been the best way to go
dickstorer
Whoever you spoke to regarding the use of the Sherline rotary table on any of their manual mills did not understand your question or was misinformed. As john mentioned, it can be mounted on any mill they ever made including with the Lathe/mill attachment.
The method of mounting as shown in your initial photo is the most efficient, in that it allows for maximum visibility as well as rigidity.

Since I cannot enlarge your divider, I am unable to see what it is.

The Sherline rotary table calibration is clearly marked and can actually work with odd ball figures as mentioned. However it is time consuming and you must be very observant as well as recording each setting before making the next.

The CNC version is just indispensable for wheel and pinion cutting.

Jerry Kieffer
 

dickstorer

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Poor choice of words on my part. It has been a long time and what was actually said was that a step motor and controller was not available for my rotary table.
 

NigelW

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The CNC version is just indispensable for wheel and pinion cutting.
Mr Tompion and others made some pretty nice clocks without CNC, but it certainly makes life easier.

During the COVID lockdown I have been unable to access my club's workshop so finally got round to investing in some more kit for my home workshop. My club has an electronic indexer mounted on a Shaublin mill which, when it reopens, I will be able to use for more exotic wheel counts but for my home setup I decided not do go down the CNC route. I bought a non-CNC Proxxon FF 500 and a Vertex rotary table with a set of dividing plates which gives me all prime number divisions between 1 and 50.
 

shutterbug

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I have seen rotary tables different scales on each side. Could yours be like that? Can it be turned over, in other words?
 

Jerry Kieffer

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A CNC rotary table offers other advantages than just indexing when cutting wheels and pinions. Or at least those I am familiar with that are similar to the Sherline version.

In The case of the Sherline, any index from two to a thousand is available in a few seconds.

If that were its only advantage, you would be restricted to the use of cutters from the same manufacturer utilizing their tooth form and to required specifications to achieve best results. If you are constructing a movement from bar stock, and have the required index plates , then of course there should not be any issues.

On the other hand if your reproducing an existing wheel or pinion, it is unlikely a commercial cutter of the same tooth profile is available. While a close fit may or may not work, I could no longer imagine not having a method of adjusting profiles for the least amount of friction.

In the case of the Sherline and likely others, a index number is selected and the wheel or pinion is machined.
At that point, the rotary table can be set in continues rotation and the mating wheel or pinion set against it at full depth. This in turn will immediately tell you if there are any fit or function issues in operation. If so, the R/C can now be returned to the zero starting point and a very slight tooth profile cut be taken. Another words the wheel or pinion can be advanced or retarded by hand wheel setting to less than .0005" or ever so slightly and the index number reinserted. At this point a slight cut is taken on every tooth and the fit is retested using the above rotation mode. This can be repeated as many times as required, however, once or twice generally resolves issues.

In addition, The Sherline table can be operated in either manual or CNC. This in turn allows crossing of a wheel by machining that requires less time and exhibits the same appearance/accuracy as a stamped or machined crossing.

For early hand cut crossing, it allows one to easily and quickly machine away about 90% of the metal to be removed. This in turn allows one to utilize most of their time duplicating the original hand work found on the original while removing the last 10%.

One other option with the continuous rotating mode is the ability to machine a blank in place achieving the highest level of accuracy that will exceed watch standards.

Jerry Kieffer
 

Kim Miller

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I made the mistake of visiting Jerry at his home in Wisconsin.............next day I ordered the Sherline CNC Rotary table.:) What a great tool! I'm building WR Smiths Skeleton clock and I used it to cut all the gear teeth and cross out the wheels. I thought it was worth the investment because I plan on building several more clocks. I also use Jerry's method of mounting the rotary table directly on the mill table and then tip the head of the mill 90 degrees.
Kim
 

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