8 Tool rotary Turret.

[xpylonracer]

Started this a few weeks ago, intend to use it on a Denford Orac cnc lathe, manually at first but may motorise later.
Maximum size of square tools is 13mm or 1/2", round tools will be up to 10mm or 3/8" diameter.

Rgds, Emgee

 

[Herbiev]

Hi Emgee. Thanks for sharing and great photos. It looks like a very well designed time saving devise. Where did you get the plans as I would like to build one also. Your standard of work is simply superb

 

[Don1966]

That is some superb work, nice tool addition also.

Don

 

[xpylonracer]

Hi Herbie

Plans of the Toolchanger are on the Yahoo Emco lathes Group, in case you aren't a member there and save you the trouble have uploaded 2 PDF files below. You will obviously have to change some dimensions to get the tool at the correct height for your lathe.
My next job is to cut some steel plate for the Toolplate so will post again when this is cut.

Rgds, Emgee

View attachment 8 Tool turret plate.pdf

View attachment Tool changer 8 tool.pdf

 

[Herbiev]

Emgee. Thanks very much for going to the trouble of posting the plans. Very much appreciated and I think several other members will also be interested in making one.

 

[kvom]

Looking at your pics, I imagine that both the ratchet wheel and the lengths of the pawls need to be very precise both for repeatability and to keep the turret from moving while cutting. With a stepper motor to help holding that would be less of a problem, but I wonder how rigid it will be in manual mode.

Your work looks first rate in any case.

 

[xpylonracer]

Hi KVOM

The pawl plates are slightly shorter than needed to allow for an adjusting screw to bear on the end so fine adjustment can be made to bring the tool slot to correct height, once set it should remain in position.
The load on the plates is when the spindle lock is off and the tool plate revolved to another position, the toolplate is turned back to the plate and the spindle lock applied, although the cutting action of the tool is trying to push the pawl into the plate the force on the plate is reduced by the spindle lock.

You are thinking where is the lock, sorry it does not show so well in the pictures, if you look at the shot where the main block is being bored, the 1/2" brass rod being held in position by a single bolt clamp acts as the spindle lock when completed, it is partly in the bore so has a segment cut that matches the spindle OD, this is cut at the centre and acts as the locking mechanism, I will post another picture to show the detail. This type of locking arrangement works very well and releases without problems when the locking nut/screw is released. This is equal to and likely a more positive lock than a stepper/DC motor reversing at less than full rated voltage.
Thanks for your interest.
Rgds, Emgee

 

[xpylonracer]

PDF file at bottom showing spindle lock detail. Best viewed with Adobe Reader 9 or better, use the "activate" button when it opens and then you can manoeuvre the model around with the mouse to view all sides. The brass rod is shown sectioned for clarity.

View attachment Shaft locking detail.pdf

 

[xpylonracer]

Just added another PDF showing a model of the Turret, included some tools but nothing in the 10mm round sockets yet.
Same as before use Adobe 9 or better and use the "activate" feature to manipulate the model around with the mouse, be patient when it loads as may take 30 secs or so.
Rgds, Emgee

View attachment 8 Position manual Tool Turret.pdf

 

[xpylonracer]

Started on the Toolplate, had to mount the plate on a rotary table so it could be accurately turned through 180 degrees, my mill didn't have sufficient Y axis travel for the total profile dimension. Pictures below show 1st cuts and then table turned for the 2nd profiling cuts using a 6mm 4f carbide cutter, used mist and enough air to keep the slot clear of chips. Also shown are 2 of the 4 tool slots, used 12mm cutter for these.

 

[xpylonracer]

Square Tool fixings now drilled and tapped for M6 cone end grub screws, leaving the round tool bores to be done in situ on the lathe, this should ensure all are at correct centre height when indexed. Hole at back bored to suit spindle end, started assembly.

 

[xpylonracer]

Rotary table has 3/4" centre hole, spigot is 3/4" with a 1/4" diameter end to locate a hole reamed in the plate before fixing to the table. Table centred to mill spindle before fixing plate down to table. The brown on the table is stain from the plywood packing used, leached out from use of coolant.

 

[xpylonracer]

Toolplate now finished, fitted the No.1 tool in place and centred the cutting tip, did some trial cuts on a piece of EN8 which were OK then checked with square toolsteel in the other square slots that they also were on centre, tightened off both pawl adjusters to maintain position.
Used a centre drill and then 5mm and 9.5mm drills aiming to ream the bores 10mm for round tools. It was visually obvious that the drills had not remained on centre so had to use a 12mm milling cutter to bring the holes to truth, then reamed to suit 1/2" tooling.
Used a flap disc to clean the scale and rust off the plate, finished with some oil base matt black to save the plate corroding/rusting, would be better if chemically blackened but I don't have any chemicals in stock and they are not as low cost as paint from stock !!!!

 

[xpylonracer]

First job for the turret was to make the Tool collets for the 4 round tools, used 1 for a centre drill and another for a 10mm boring bar, 2 spares left undrilled and not slit. Tool rigidity appears to be OK, turned and parted without problems as you would expect with brass, will confirm again later when I have some tough steel to turn.

 

[xpylonracer]

Quick update on use. Normal turning of tough steel did not cause any problems for the turret, using the 1/2" round sockets for tools does need some thought to prevent colliding with the chuck when in use. If a 3" chuck was used there would not be the same problem, current chuck fitted is 4" diameter. More pictures to follow.
Emgee

 

[lsteele]

Hi Xpylonracer,

It looks like you've modified the tool changer from the original drawings. Do you have drawings or better still CAD models for your version?

Thanks,

Luke

 

[xpylonracer]

Hi Luke

Toolplate is almost the same as plans, had to modify the block, spindle pawl etc to suit my lathe cross slide to centre height, also to use materials I had in stock such as Cast ally block, 1" Stainless for shaft, EN8 1.75" diameter for pawl, phosphor bronze bushes. The toolplate is only 20mm thick, another stock piece, I did have to buy some socket caps and grubscrews. I have some drawings but dimensions may need changing to suit your lathe centre height, I will look these up and post ASAP.

Rgds, Emgee

 

[lsteele]

Hi Emgee,

Actually I have an Orac too - correct me if I'm wrong but I believe that's what you're using this on?

The drawings or anything else you have would be great.

Was the tool changer in the drawings you posted designed for a standard Emco compact 8? I'm just wondering if you have any clearance issues with the tool plate as designed.

Thanks,

Luke

 

[xpylonracer]

Hi Luke
Some files attached showing main dimensions, these suited my Orac without too much toolplate rotational adjustment, then locked off to retain repeatability when indexing turret.
Only clearance issue is as stated earlier, round tools fouling the chuck if not planned correctly. This could be overcome to some extent by increasing the diameter of the toolplate, thereby spacing the tools further apart and at greater diameter than the chuck, only if the jaws don't extend from the chuck increasing the OD.
Unable to upload DRG files so converted to jpg, are you in UK ?
Rgds, Emgee

 

[lsteele]

Hi Emgee,

Great, thanks.

Yes, I'm in the UK - London.

Do you have the drawings for the body that houses the bearings etc? What kind of bearings did you use?

Is there any chance you could upload a zip file with the original CAD models? (zip files are permitted as attachments apparently).

Thanks again,

Luke