The chuck is self-centering.

To centre my rotary table I have a centered plug which fits into the rotary table centre. This allows put a centre into the mill spindle and just run it down to the rotary table to centre it to the spindle then bolt it to the mill table.

As already mentioned, using a centre in the mill to locate in a hole in the RT (or vice versa) is a quick set-up method for most work.

For a more accurate set-up, mount a dial indicator on the mill spindle and use it to locate on the morse taper of the rotary table spindle. (or the machined recess on the end of some RT's). Carefully turn the mill spindle by hand to achieve zero movement of the indicator. Bolt down the RT and check again to see if it has not moved.

Then attach the 4-jaw chuck and use the dial indicator to position the work. (4-jaw chuck could be attached prior, if there is access to locate on the RT morse taper for the initial set up)

Paul

I suppose a lot depends on the part or parts you are working on as well as what other tooling you have as to what's the better method to use for holding work on the R/T.

On thing mine get used for quite a lot is rounding over the ends of rods etc, in fact the 6" ARC one tends to stay fixed to the SX2.7 most of the time with it's 3-jaw so it's ready to go for just this type of work. Looking back through the photos of my Victoria build that's the only thing the R/T was used for and all done with the 3-jaw.

Over the years I have built up a fair number of simple arbors which get reused or it's not hard to knock up another and these just go into the chuck and the work screws to those. Not sure I would want to try clamping this 1/4" sq x 3/8" long part direct to the table and still be able to get at it will a 6mm cutter and not hit any clamps

The Cylinder legs may have been easier to clamp being larger but still quicker to just screw to the arbor

As you don't have any form of indexer like a 5C spin indexer you will end up using the R/T to cut square or hex shapes onto small parts which will again be quick and easy to hold in a chuck or collet fixed to the table

I'd concede that a chuck might be the simplest solution, but not necessarily the most accurate. My rotary table has a 1" parallel hole in the centre, which is way more useful than a Morse taper. So I'd make a 1" spigot with a flange for clamping to the table and a recess to locate the work. There would also be a hole for a screw into the part to be machined.

Andrew

My advice is not to get wrapped round the axle worrying about the quality of hobby tools. If the best possible rotary is really needed (and I suggest it's not), then buy an industrial model. It will cost a few thousand pounds, and although it will be somewhat more robust, don't expect it to be bullet proof. Many a well-made rotary table has been wrecked hacking out big wheels for model traction engines!

Most hobby rotary tables are of the HV6 design. A worm drives a cogged wheel and turns the table on a simple plain bearing. Though obviously made down to a price, they're reasonably accurate and sufficiently sturdy for most amateur purposes. They're aren't high-technology, nowhere near as difficult to make as a computer hard disc.

The buying strategy for this class of affordable tool is quite different from the good old days. Until about 1960, tools were so expensive it paid to get the best one could afford in hope it would last a lifetime. Not a good idea to buy cheap back then, because there was a sharp divide between well-made and cheap and nasty. There were brand names that could be relied on, so what grandad said about them was worth listening too. This world has pretty much gone.

Today the world is flooded with mid-range tools, affordable rather than excellent. Not intended to last forever, they are nonetheless generally acceptable for the light duty found in typical hobby workshops. Many products come from similar anonymous factories, and are rebranded by a local seller. But be aware that some versions are too cheap, or customer returns, or manufacturer rejects. The customer probably has no idea who made the item, or even which country or countries it came from. And for this class of kit, it rarely matters. The customer isn't looking for 'quality', he's after 'value for money' and 'fit for purpose'.

So, rather than spend ages looking for a magical brand-name, I suggest a more appropriate procurement strategy is to:

• De-risk the purchase by buying, with a credit card, from a reputable UK supplier. If the product is found wanting, exchange it. No angst necessary!
• Consider inexpensive products to be disposable: an ordinary rotary table only has to deliver value for a few years, then replace it.

'It won't last' scream the old-school! True, nothing does. The point is, at the moment, hobby-market Rotary Tables and the like don't have to.

Main exception to value for money purchasing is bragging rights: you can't boast about Far Eastern hobby equipment! Don't care myself because tools only have to do what I want of them, and that doesn't include impressing the neighbours!

Dave

If it possible to mount the work vertically in the vice or chuck, to produce a square. you only have to run the cutter along each side, in turn, to remove enough metal to leave a square of the size that you want.

To align the Tailstock with the R T when used in horizontal mode, my method is.

Obtain a blank arbor with taper to fit the bore in the R T, and carefully bore it to be a snug fit on the barrel of the Tailstock. (As indication of the fit, mine goes "pop" when the arbor is pulled off the barrel )

My Tailstock is aligned to the T slot by means of stepped dowels, so the R T is aligned by fitting the Arbor into the R T, with the securing bolts slack.

For the first time alignment, the clamp bolts for the vertical position of the tailstock barrel are left slack.

In this way, with the R T in a suitable position on the table, the Tailstock is clamped to the table, so that the Tailstock barrel can be inserted into the bored arbor.

For the first time alignment, by leaving the vertical clamps for the Tailstock barrel loose, as the R T is aligned with the Tailstock, the Tailstock barrel is now aligned in the vertical plane, with the R T., and the clamp bolts can be remain tight and untouched for the future.

The Tailstock barrel locates the R T.so that it can be clamped to the table. The Tailstock can then be repositioned wherever is suitable along that T slot, for the work in hand.

Howard

When you come to use the R T in the Vertical mode (Table face vertical, axis horizontal )) you will need yto align the R T and the Tailstock.

My Tailstock has tappings for a key or dowels. Because my T slots differed in width from the keyway on the Tailstock, I made up two stepped dowels. One end is tight fit in the Tailstock keyway, and the other in the T slot of the Mill table.

So that is the Tailstock aligned to the Mill Table. It now needs to be be aligned vertically, with the R T.

The RT also needs to be aligned with the axis of the Tailstock, along and across the Mill table..

These can both be done at the same time.

With an arbor (In my case 2MT ) bore the blank end to a really snug fit around the OD of the Tailstock centre.

Position the R T, loosely, on the Mill table so that it roughly aligns with the Tailstock, in the place where you wish to use it, with the 2MT alignment arbor in place…

Slacken the clamps for the vertical position of the Tailstock centre

Enter the Tailstock Centre into the bore of the 2MT alignment arbor., and clamp the Tailstock to the Mill table.

The dowels will have aligned the Tailstock.

The Centre barrel, being snugly located in the 2MT arbor will have aligned the Tailstock barrel vertically; and the R T along and across the Mill table, so both can be clamped.

Once the Tailstock centre barrel has been aligned, it is set up and should not need to be reset. It can be used, with the 2MT arbor to align the R T on the Mill table in the future.

HTH

Howard  (Anyone know a good typist? )

Edited By Howard Lewis on 20/09/2021 17:36:13

I went for the small set of finger collets, 6, 10, 12 and 16mm although I have used all of them it's the 6 and 10mm that's gets used the most as they take the majority of my regularly used cutters.

I suppose one could argue that with just a small protrusion and a direct fit in the mills R8 taper they must be stiffer than a tool mounted in a chuck with a 40mm extension from the taper. However having said that the R8 collet chuck is quite a rigid bit of tooling and I suspect that in practice you would never see any difference between it and the finger collets.

Something that Jason has mentioned on occasion and which I have found to be true is when using the smaller cutters they get a bit lost under the spindle when mounted in a finger collet. With a small protusion and been so close to the spindle it can be difficult to see the cutter, especially on flat work down close to the mill table. You have to bend down to get the tool at eye level should you need to see/watch it or mount the work higher if possible, just something to be aware of.

Ron

Some years ago I purchased a 6" Shobha table and dividing set from Chronos. Never had the need to use the dividing plates till last month. The project was to use the Elliot 10m to shape 19 tooth x 14DP gears. It all went well fitting the dividing plate to the gear cutting jig to index for 19 teeth. The gear looked good but had some tooth spacing errors. After a few more attempts and eliminating any error sources the gears were not much better. On measuring the dividing plate the holes were on a constant radius with over 1mm variation between the hole spacing. Not a dividing plate but a steel disk with randomly spaced holes. Will go off and get a Vertex set as soon as the lock down in Melbourne ends. Kevin.