# how to use a rotary table



## knapper (Jun 5, 2012)

I was cruising through some of the adds and junk mail that I get every day and
came across and add for a rotary table... It is a 6 inch, both vertical and horizontal
for the price of $178.00..There are no attachments for it yet.
Now I have thought for a long time that I should have one of those. So sent for it
and it arrived a few days ago and now I am trying to figure out how to use the 
darn thing.. 
I have a job in mind but don't know where to start.. I have some 1/4 inch 6061
aluminum plate that is cut 10 & 1/4 inch square and I need to make it into a 10
inch round with a 1 inch hole in the center..Picture a 10 inch table saw blade..
My machine is a SMITHY IMAX, Granite Series, 13 X 40, 3 in 1..
I know that I will need those index plates, but I don't want to jump out there and
 spend a lot of $$$ on add ons right away.. Kind of like buy what I need first?? So
it don't just set in the tool bin and look pretty.. My financier (wife) gets a little
upset if I do that..She is also, the cook and it isn't safe to irritate the cook any
to often..

Some ideas and  guidance would be helpful

Knapper


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## PurpLev (Jun 5, 2012)

knapper said:


> I have some 1/4 inch 6061
> aluminum plate that is cut 10 & 1/4 inch square and I need to make it into a 10
> inch round with a 1 inch hole in the center...
> My machine is a SMITHY IMAX, Granite Series, 13 X 40, 3 in 1...
> I know that I will need those index plates...



obviously the better way to go about it is to turn this, but if your Smithy doesn't have 10" capacity that won't do you any good 

the other thing is that you got a 6" rotaty table, so even that is rather small for the desired 10" disc you want to make. Theoretically you should mount your 6061 plate to a substrate (plywood, or other expandable material as you'll be cutting into it). secure this to your rotaty table via a center hole, and clamps on the outer rim for rigidity, set the rotary table on your mill table so that the center of the RT is 10" +half cutter width away from the cutter (so that rotating the table with the cutter engaged will result in a 10" disc part) and then using the rotary table to rotate your plate while the cutter is engaged in it to 'turn' the disc - you can then mount the disk + substrate directly on your mill table, index your center hold and bore that 1" center hole with a drill/end mill.

the above is theoretical since your RT is only 6" so Im not sure how you would reach your RT wheel, IF you are able to mount all of this without it interfering with the RT body itself (you'd need to elevate the plate+substrate a couple of inches above table). all doable, I'm just not sure how rigid it will all be.


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## swatson144 (Jun 5, 2012)

Like most everything in machining lots of different ways to spank that monkey. It all depends on if you mind holes outside of the center or not. I'll just get onto the no extra holes allowed band wagon.

Center the rotab under the spindle and clamp it. Note the center position and direction of travel to get to them. Then mount a sacrificial plate using T nuts and CS screws. Leave the sacrificial plate slightly large as you will need it for clamping the work piece. Drill holes for clamping rigs in the sacrificial plate. Mark an x across the workpiece to find center and center punch it. Place a center in the spindle and center the workpiece under it, clamp and cut the center out or cut the outside first as you want. I'd probably cut the 1" hole first so I could drop a piece of round through the workpiece and 1/2 into the sacrificial plate before moving to the outside cut. 

Steve


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## MikeAa (Jun 6, 2012)

A quick tip, I turned a mandrel on my lathe that is just a slip fit to the center bore of my rotary table with a 3/4" shaft to fit an R8 collet. Zero out your table and the use the mandrel to center to your spindle and the tighten it down it down to the table. Move the 5 inches on your zeroed handwheel plus cutter *RADIUS* and your there.


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## swatson144 (Jun 6, 2012)

MikeAa said:


> plus cutter diameter and your there.



Errr I think that would be cutter radius? :huh:

Steve


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## Rbeckett (Jun 6, 2012)

Knapper,
If you have a look at Amazon they have a workshop series that I am pretty sure included a rotary table primer.  There are around 40 or so books in that series and they are really nice little how-to books for the machinist.  I have several.  The actual title from one is "Workshop Practice Series"  Milling A Complete Course, by Harold Hall.  That should get you enough info to find the one you are looking for, hopefully.  I like them because they dont talk over your head and assume you know very little so they start at the beginning and progress through a whole project to make sure you have gotten it down.  Really a great source of training literature.  Hope this helps some.
Bob

Heres a link to two of those books that might interest you:
Gears & Gear Cutting (Workshop Practice Series 17) , and 
Dividing (Workshop Practice), book 37


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## MikeAa (Jun 7, 2012)

"Errr I think that would be cutter radius?"



Fixed it, my bad!!!


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