# What to look for in a used rotary table?



## nnam (Jun 15, 2019)

What are the size ranges that would be ok general purpose homeshop use?

What else besides the usual wear, tear, slack and precision?


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## Ed ke6bnl (Jun 15, 2019)

I started with a 12" than 10" still a bit too heavy I would say 8 in. Is ideal


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## MrWhoopee (Jun 15, 2019)

Any damage to a rotary table will be visible. It is highly unlikely one has been used enough to cause wear. A larger one obviously has more capacity. It also has more capacity to injure your back. It's a balancing act. Only you can determine the balance point.


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## Mitch Alsup (Jun 15, 2019)

I have a 10" horizontal table--it is at the limit of what I can lift.
I am (sort of) looking for an 8" vertical table, with spindexing disks, and a 3 or 4-jaw chuck.


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## richl (Jun 15, 2019)

I like the 6" size, but I also have a 8", if you put a chuck in it, you need to factor the extra size and weight. The size of your mill is also a consideration.

As for wear and tear visual gauges help give an indication of the life it has led. I would also make sure it turns freely over it's full range. Check the disengage mechanism to make sure that works.

Hth


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## Technical Ted (Jun 15, 2019)

I've got a 10" and can handle it OK, but I'm in pretty good shape for my age (64 in 5 days). I wouldn't want any more unless I used my engine hoist or had a crane, lift table, etc..

Ted


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## nnam (Jun 15, 2019)

Thanks for the advice about the weight. Although I don't do this often, but I have a patient  lift, it is light and foldable.  I use it more than my 2 ton engine lift.
I used to have a battery operated one, but gave away because I didn't have space.

They are still more cumbersome than my two arms. So weight is important factor.


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## BROCKWOOD (Jun 15, 2019)

While weight is a very important factor for the sake of the back, I'll add that headspace is a factor that cannot be dealt with. If your rotary table robs too much space beneath your spindle:  You're stuck & limited to short stock. Perhaps turning the Rotary on it's side & using an angle head is a solution. Only you know what can & cannot be done with your particular equipment / needs / budget.


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## projectnut (Jun 15, 2019)

Ed ke6bnl said:


> I started with a 12" than 10" still a bit too heavy I would say 8 in. Is ideal



I'm in the opposite camp.  I currently have an 8" rotary table with both X and Y axis movements.   Many times I find it too small.  I am currently looking for a 12" or 15" model.  Weight isn't a concern in that it will be lifted to a hydraulic cart with an overhead hoist, then slid onto the mill table.

When looking for a table make sure there is no play at the worm gear, or if there is play that it can be adjusted out.  Also if it has the X and Y movements make sure there is a gib to adjust each of the ways, and the bearings are tight at the crank handles. 

My current table is an Eron brand built sometime in the late 70's or early 80's.  Below is one like it that was listed on eBay a while ago.






Mine spent it's life in a prototype shop where it was used on an almost daily basis.  Between it's use there and another 15 years in my shop the acme rods wore the hole through the casting about .015 oversize. A few weeks ago I had to disassemble the table and bore the casting to insert bushings.  All is tight now, and I expect it to last several more years.  It wasn't that hard a job on an 8" table, but would have been far more difficult on a 15", 18" or larger model.


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## mikey (Jun 15, 2019)

I have to ask how big is your Mill? That has a great deal to do with the size you get. The table has to be large enough to hold the work while still allowing enough room for your tooling.


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## mmcmdl (Jun 15, 2019)

Horizontal and vertical , small ( light )  enough to lift . As Mike said , you need tool clearance if you don't have a riser .


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## nnam (Jun 15, 2019)

mikey said:


> I have to ask how big is your Mill? That has a great deal to do with the size you get. The table has to be large enough to hold the work while still allowing enough room for your tooling.



Mine is same model as this:









						Coburn Precision 500 Horizontal Mill
					

I was browsing around a local used machine dealer and bumped into a Coburn Precision 500 horizontal milling machine. I've never heard of the company or the mill before but its a nice hobby sized horizontal mill and it comes with a vertical head attachment. The dealer mentioned it may be missing...




					www.hobby-machinist.com
				




and this:





__





						A M Metalmaq Inc
					





					inv.ammetalmaq.com
				




But I don't have vertical attachment.  So I am doing the horizontal face mill with the NMTB #40.

It's very inconvenient and I hope to get or make a vertical head somehow.

I was asking about this since I followed the divider head thread, then I was thinking what if I am keeping an eye on used local stuff, and may get a decent deal.  That's why I am getting the info for now.


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## mikey (Jun 16, 2019)

Okay, the knee has only 8" of vertical travel, which is not a lot. Keep in mind that the diameter of the rotary table is also tied to its vertical dimensions ... in general, the larger the diameter, the taller the height. You also need to account for the work holding method you need or plan to use. If you choose a vise or jawed chuck, just the size of that work holding device, when placed atop the rotary table, may make doing practical work near impossible. 

My suggestion is to find the dimensions of whatever rotary table catches your eye and build a cardboard mock up of it to place on your mill to make sure you have enough room to use it. I did that on my RF-31, which has 14" of vertical travel and I chose to buy a 6" rotary table. An 8" would have fit but if I also put a 2 or 3" screwless vise on top of that and then tried to use an ER-chuck to hold an end mill, I would have had a difficult time machining a lot of my projects. A simple 3 jaw chuck would have been even worse. 

Good luck!


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## nnam (Jun 16, 2019)

mikey said:


> Okay, the knee has only 8" of vertical travel, which is not a lot. Keep in mind that the diameter of the rotary table is also tied to its vertical dimensions ... in general, the larger the diameter, the taller the height. You also need to account for the work holding method you need or plan to use. If you choose a vise or jawed chuck, just the size of that work holding device, when placed atop the rotary table, may make doing practical work near impossible.
> 
> My suggestion is to find the dimensions of whatever rotary table catches your eye and build a cardboard mock up of it to place on your mill to make sure you have enough room to use it. I did that on my RF-31, which has 14" of vertical travel and I chose to buy a 6" rotary table. An 8" would have fit but if I also put a 2 or 3" screwless vise on top of that and then tried to use an ER-chuck to hold an end mill, I would have had a difficult time machining a lot of my projects. A simple 3 jaw chuck would have been even worse.
> 
> Good luck!


That's a wonderful way of looking at it.  I never thought about that.  So this is a no go for me for now.  Maybe when I buy a vertical mill or something bigger than this.


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## mikey (Jun 16, 2019)

Quite often, a rotary table is purchased because we envision needing it in the future, only to find that it often sits unused for long periods of time. Not a great way to store your money. Best to buy one when you really need it and not before.


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## projectnut (Jun 23, 2019)

In my previous post on this subject I mentioned I was looking for a 12" to 15" rotary table for some larger work.  Yesterday I was able to purchase a 12" Index brand table for a reasonable cost.  This is a little older table in that it's labeled "Index Tool & Machine Works" rather than Wells-Index. The next steps are to clean it up and possibly grind the top to remove some past indiscretions.


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## seanb (Jun 23, 2019)

nnam said:


> What are the size ranges that would be ok general purpose homeshop use?
> 
> What else besides the usual wear, tear, slack and precision?


I have a bridgeport j head machine would not go any bigger than 10" would definetly want both horizontal and vertical


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## Larry42 (Jun 23, 2019)

I recently bought an 8" RT, tail stock, index plates & a 3 jaw chuck. I have a 9x49 Jet that is a Bridgeport knock off. Turns out I can't really use the chuck on the RT due to not enough Z-axis. Clamping things directly to the RT works but even the strap clamps add Ht. They also take up table space greatly reducing the available area for the work. I've decided to make a pallet for the RT to add size and methods of clamping. The Vertex table only has 3 slots that also limits your clamping choices. Now I'm seriously considering a riser for the mill. That also means a power drawbar. One thing leads to another. 
By the time you put a drill chuck in the spindle + 4" of RT + even a screw bit it doesn't leave much for the work. 
As for the wt. an 8" table weighs about 55#s adding a chuck makes it heavier than I feel comfortable lifting.


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## projectnut (Jun 23, 2019)

I guess I'm not understanding the height problem with rotary tables.  My 8" table with both X and Y axis movements stands only 5 3/8" tall.  The "new" 12"(no X & Y movements) one is only 5" tall.  My Palmgren 8" vise is 6" tall and my 6" Bridgeport vise with the swivel base is 7" tall.  I've yet to need to mill anything I couldn't fit under the quill.

Both my rotary tables are horizontals only.  If I nee to something on a vertical axis I clamp them to an angle plate


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## Larry42 (Jun 23, 2019)

Depends on the size of the parts. Spindle nose to table max 17.5". RT thickness 4". For milling Length of tool 3" + 3/4" strap clamp Leaves 9.75 for max work. But now mount a drill chuck leaves 6.25" but wait I want to use a boring head even less work space left. Then I decide I'd like to use the 8" chuck so I can rapidly swap out parts, 4.75", I'm down to 2.25" that can be sticking out of the chuck. 
I work on quite a few castings. Besides being bulky they are often awkward to mount. 
       You're right though, for much of what us hobby types machine there is probable plenty of room. I got started on this because I had recently mounted a casting that had been repaired (brazed) and needed to be re-bored and have an O ring groove machined. It just barely fit on my mill.


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## projectnut (Jun 23, 2019)

Spindle nose to table clearance on my Bridgeport BR2J is 18 1/2".  I've been close a few times, but always able to get the part milled.  If it was just an inch shorter it might have made the difference between working and not working.


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## RobertHaas (Jun 24, 2019)

I have a 16": Bridgport rotary table. It is for sale to anybody strong enough to load it in their truck


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## silverchips (Jun 25, 2019)

mikey said:


> I have to ask how big is your Mill? That has a great deal to do with the size you get. The table has to be large enough to hold the work while still allowing enough room for your tooling.



I have to totally agree with Mikey.
We can be guilty about having a super cool looking rotary table in our shop but most that can be found for sale used are too big and sits in a corner unused collecting dust. Height is another big issue and usually proportional to the diameter so take that into consideration of how much daylight your mill has and the projects you envision using it for. 8" of daylight is not much but it's a horizontal mill which is less of an issue than with a vertical mill.
Two other things to look for is a rotary table can also mount vertical as well as horz. and that the table has a center hole with a taper (MT3 taper or something ) to hold tooling. This will greatly expand it uses and options on a home mill.


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## jmcghee (Jun 25, 2019)

FWIW I have an old 9” troyke for a 48” table Bridgeport and it’s absolutely perfect. Any smaller would be too small, any bigger too big


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## projectnut (Jun 25, 2019)

Keep in mind size is a relative thing.  Things that seem large to some people are just the right size for others.  The company I worked for stored excess machinery in a warehouse owned by a local moving and storage company.  In one end of the building was a 36' diameter Niles Vertical Boring Mill.  The University of Wisconsin had purchased it from the Harnischfeger Company in Milwaukee when they were bidding on the super collider project.  They lost the bid and sold the mill at auction for peanuts.

The new owner thought he was going to make a killing cutting it up for scrap.  He hired several contractors to do the job, but they all failed.  He finally hired a consultant to determine the best way to break it into pieces small enough to be sent to a foundry.

The consultant determined that the castings were so thick about the only way to break it up was to use directional explosives.  Unfortunately the cost of breaking it up exceeded the scrap value.  He defaulted on the storage bill and the mill became the property of the moving and storage company.  As far as I know it's still setting there.


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## Meta Key (Jun 26, 2019)

jmcghee said:


> FWIW I have an old 9” troyke for a 48” table Bridgeport and it’s absolutely perfect. Any smaller would be too small, any bigger too big



Agreed!  I have the same 9" Troyke and it works great on my Clausing 8520 mill. Easy to handle, the weight and size are perfect as far as I'm concerned.

Oh, yeah, I forgot --- pics or it didn't happen:






Probably 10, 15 years ago.  Maybe 20..  Still have the Clausing and that rotary table.  They both still look the same today; unfortunately I do not!  

I don't use the rotary in a vertical fashion.  I have an Ellis dividing head for that sort of thing.

-MK


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## JohnG (Jun 26, 2019)

I read a lot of good advice on this subject on H-M before I bought this 8" Kamakura table.  It seems just the right size for a horizontal table on my mill, but I think it would be big and awkward as a vertical table.      




I stripped it, painted it gray to match my Millrite, and made 4 T nuts for the table slots.  Here's its first job milling a 4" diameter relief in the end of a repurposed piece of 7" x 7"x 3/16" wall steel channel.  A pair of these will be guards for very scary woodworking cutters.  I wasn't sure about fixturing this on a wooden block, but it worked nicely.


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## ezduzit (Jun 27, 2019)

Get as large a rotary table as you can fit on your machine. 
The first part I ever made on a milling machine required the use of a rotary table. Fortunately I had found a used 12" Troyke vertical/horizontal in excellent condition, for use on my ancient Index mill. This aluminum part is a boom end fitting for a sailboat. Boom diameter is 4".


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## silverchips (Jun 27, 2019)

I have to agree about using the largest rotary table possible, just as long as it fits the mill table and means to move it around easily.

Interesting fitting, a round section for a boom with 2 reef lines and outhaul with only a small 4" dia. section. Nice job and very rare to see quality work like that being done in MDR. I like the detail on capturing the sheave pin.





ezduzit said:


> Get as large a rotary table as you can fit on your machine.
> The first part I ever made on a milling machine required the use of a rotary table. Fortunately I had found a used 12" Troyke vertical/horizontal in excellent condition, for use on my ancient Index mill. This aluminum part is a boom end fitting for a sailboat. Boom diameter is 4".


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## ezduzit (Jun 27, 2019)

silverchips said:


> ...Interesting fitting, a round section for a boom with 2 reef lines and outhaul with only a small 4" dia. section. Nice job and very rare to see quality work like that being done in MDR. I like the detail on capturing the sheave pin.



Thank you. I milled a slot for the sheave pin cap, so there is no load on the retaining screw. The sheave pin I turned on the lathe and press fitted it into the cap before welding. That was also my first lathe project. Got into machining very late in life. I'm 75; this was just a few years ago.


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## Bob Korves (Jun 27, 2019)

Think outside the box.  If you want to put bigger work on a smaller RT, then put an oversize sub plate on the RT to the size that you need.  Of course, rigidity is another issue...


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## Larry42 (Jun 27, 2019)

Very nice. Complex part. The blends are beautifully done. I'll bet the original was cast and not nearly as slick. 
I'd like to get setup for anodizing.


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## ezduzit (Jun 27, 2019)

Larry42 said:


> Very nice. Complex part. The blends are beautifully done. I'll bet the original was cast and not nearly as slick.
> I'd like to get setup for anodizing.



Thank you.
Yes, the original was a very simple cast piece with no sheaves.


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