Thread: Rotary Tables

Originally Posted by wm460

Hi Kev,

Who is the H&F agent in Darwin?

If you are thinking of getting a chuck and dividing plates as well this is a better deal than H&F will have. 6"/160mm Vertical & Horizontal Rotary Table, 3-Jaw Chuck, 3-Dividing Plates Kit | eBay

Originally Posted by Ueee

If you are thinking of getting a chuck and dividing plates as well this is a better deal than H&F will have. 6"/160mm Vertical & Horizontal Rotary Table, 3-Jaw Chuck, 3-Dividing Plates Kit | eBay

Maybe my eyes are deceiving me but the RT seems to have 4 T slots and the chuck has 3 hold down bolts? Doesn't line up very well by the looks.

Probably on sitting on it for picture purposes,there would be no problem setting it up to run true.

Originally Posted by pipeclay

Probably on sitting on it for picture purposes,there would be no problem setting it up to run true.

If the RT has 4 T slots, which it appears to have, then they are are at 90deg to each other, the chuck has 3 hold down bolts, ie at 120deg to each other. Be a bit difficult to line them up to the T slots, wouldn't it?

4 Bolts and T nuts sitting next to it. Short bolts. Looks to be bolts already in chuck. I would think that chuck backplate would mount first with the 4 bolts/T nuts, centre that then attach the chuck to backplate. Just my take on it. It is a nice setup. I have been thinking about a rotary table since I bought my mill but it is a lot of money for what I would use it for.

Dean

Yes that would be difficult if not impossible but that is not the case here as the chuck is sitting on a mounting plate, wouldn't matter how many holes were in the chuck as long as the chuck is mounted concentric to the mounting plate and the mounting plate is set concentric to the rotary table.

I haven't seen a chuck mounted direct to a tee slotted rotary table,but that's not to say that there not out there,if that was the case then you would need a rotary table with corresponding tee slots to accomadate the locating holes of the chuck.

Originally Posted by fxst

well they are not that hard to make. I made my own worm gear and used a 60t gear (old lathe change gear),bought a bearing, welded up a base, milled it and some time and ok its only a 4" but doest the job. Also made my own dividing head as per the book from Harold hall.
Heres a link to another R/T build Building a Rotary Table for the Taig Part Two
Have a go and amaze yourself
Pete

There are a number of builds of rotary tables in other forums. I have recently read thru a couple including the one in your link. Having thought thru the whole process in relation to my materials and equipment I have decided it is indeed doable. The steps need to be taken in exact order at times so care is needed to think before you act. I have some 20mm plate and a round piece of 30mm plate 240 diam with the usual circle starting slot in it from the plasma.

I haven't decided whether to go ahead or not yet. Comments made in this thread (I think) suggest that a 6inch table would not be big enough to cover everything. First I need to work out what size I want. The worm/gear is another issue. A number of people have said that worm and gear sets are available from EBay. I haven't been able to find any. I have read about making these quite a few times. My current lathe is not able to cut acme thread due to cross slide screw slop. I will have to wait until I get the new one installed to do this.

Dean

Originally Posted by pipeclay

Yes that would be difficult if not impossible but that is not the case here as the chuck is sitting on a mounting plate, wouldn't matter how many holes were in the chuck as long as the chuck is mounted concentric to the mounting plate and the mounting plate is set concentric to the rotary table.

I haven't seen a chuck mounted direct to a tee slotted rotary table,but that's not to say that there not out there,if that was the case then you would need a rotary table with corresponding tee slots to accomadate the locating holes of the chuck.

Must have been seconds in that! LOL.

Dean

Originally Posted by pipeclay

Yes that would be difficult if not impossible but that is not the case here as the chuck is sitting on a mounting plate, wouldn't matter how many holes were in the chuck as long as the chuck is mounted concentric to the mounting plate and the mounting plate is set concentric to the rotary table.

I haven't seen a chuck mounted direct to a tee slotted rotary table,but that's not to say that there not out there,if that was the case then you would need a rotary table with corresponding tee slots to accomadate the locating holes of the chuck.

Must admit I missed the mounting plate as I "assumed" the chuck was mounted the same I mounted mine.

https://www.woodworkforums.com/f65/mo...tex-rt-162158/

So there is at least one out there that is mounted direct to the RT.

Seems a lot more work to make sure that first of all the plate is concentric and then do the same for the chuck.

Originally Posted by Big Shed

Must admit I missed the mounting plate as I "assumed" the chuck was mounted the same I mounted mine.

https://www.woodworkforums.com/f65/mo...tex-rt-162158/

So there is at least one out there that is mounted direct to the RT.

Seems a lot more work to make sure that first of all the plate is concentric and then do the same for the chuck.

The chuck should locate accurately to the back plate if all is well but I agree with what you say. It would be more accurate to adjust the chuck indicating off an object mounted in the chuck which would compensate for any wear or inaccuracy in the chuck.

Dean

Originally Posted by Big Shed

Must admit I missed the mounting plate as I "assumed" the chuck was mounted the same I mounted mine.

https://www.woodworkforums.com/f65/mo...tex-rt-162158/

So there is at least one out there that is mounted direct to the RT.

Seems a lot more work to make sure that first of all the plate is concentric and then do the same for the chuck.

Given that a RT is likely rotating at less than 1 rpm (so no out of balance at speed issues) and anyone who wants things accurate rather than 'near enough' is going to use a 4 jaw chuck and dial things in, I fail to see what extra work could be involved.

However I have very limited use for a 3 jaw chuck except for rough work (I go from collets to a 4 jaw as a rule), so maybe it's OK.

PDW

If the 3 Jaw is mounted like Freds and mine is, you can back the bolts off and adjust the work true anyway. Once true the chuck you should be able to re-chuck things to within the chucks accuracy. Of course, for smaller work an ER collet chuck (up to 25mm in ER40) can be used in the RT's taper, or you can use a dead center and drive dog with a tailstock for mandrel work. Like most things there are many ways to do one task.

Originally Posted by Ueee

If you are thinking of getting a chuck and dividing plates as well this is a better deal than H&F will have. 6"/160mm Vertical & Horizontal Rotary Table, 3-Jaw Chuck, 3-Dividing Plates Kit | eBay

Thanks for that link.
I was asking about the agent, as Darwin is only 1000km from which would be a big savings in freight for me when buying machinery, am looking at getting a mill.
Plus if I drive to Darwin I can call in to see Kev, He told me a while ago if I every pasting through to drop in for a beer.

Hi all,

when I was looking at RT, I entertained the idea of making my own. I then looked and looked for worm/gear sets on ebay and other places and never found anything suitable. I ended up buying the Vertex 8" RT. I'm glad I did as now I have one I can see that for me, it would have been a very very difficult task and in the end would have still cost a bit and I would probably not been happy with the end result!

They are reasonably well made. After machining some CI I decided to disassemble the RT to clean (yea OK and to have a sticky beak!) and was reasonably happy with the design and build quality........ I'm so so glad I bought one!

Having said that, I was a little disappointed at the lack or complete absence of any thrust bearings on the worm shaft. Merely a bush at one end (not designed to be load bearing as the instructions state to only machine in CW direction) and another threaded bush (for preload adjustment) with a spring type washer at the other end.

I have nearly completed this rotary indexer:
Rotary table indexer - Page 52 - CNCzone.com-The Largest Machinist Community on the net! If you use scraped parts etc, it should not cost anymore than a set of dividing plates and is much more flexible in use.
(Just waiting on the stepper motor to arrive so I can make the mounting bracket)

Anyway, I was hoping to reduce a small amount of existing backlash (about 6' of arc). I'm now in the process of replacing the bushes with a 1 needle roller thrust bearing and 1 standard thrust bearing. Without making modifications to the eccentric worm carrier, there is not a lot of room to play, hence the needle thrust bearing. These mods should also further reduce any drag and keep things pretty tight.

Once the rotary indexer is complete, I hope to post in the "latest project" thread.

Cheers,

Simon