Thread: Rotary Table questons

It does add up to 185mm though, which is close.

Dave

Coming from a guy that wants me to fix a 0.04mm taper :P
Turns out the table is 255.3mm and the gap is 11.8mm which is 90% closer

I'm pretty sure I have a set up that will let me machine the back face. I'll give it a go in the morning.

Stuart

If I was to design a turntable, what would be the attributes?

For starters, ultra low profile, 200mm dia, what else. How many turns of the handle to turns of the turntable? What fixings? Tee slots, provision for a chuck?

You tell me.

Ken

For the work involved and cost of materials, you would be better off buying one.

Dave

Ken I don't think I would ever try to build a full on rotary table. But a simple indexing table would be more doable and cheaper. If you didnt want to make gears it should be ok.
Stuart

Originally Posted by Stustoys

Will I finished the T nuts today. No need to tell SWMBO that I blued/blacked them in the kitchen. They are more blue/purple in the flesh.

If you are interested in blueing, this is a good little book.
Firearm Blueing and Browning - Google Books

Some of the chemical names are old though eg lye for caustic soda.

Years ago when I was on the tools as fitter, I worked with a bloke who was a tradies assistant. ( he was actually a lot better fitter than most of the fitters, myself included) Anyway he did a lot of gunsmithing as a hobby. He used to make some beautiful stuff. All odd ball calibers and cartridge sizes. He showed me how to blue using his own recipe. I can't remember the exact ratios but it was something like about a 500 gram margarine container of ammonium nitrate (fertilizer) per 5 litres of 50% caustic soda solution. The ratio isn't all that critical. In a steel container, bring the solution to the boil (outside as it gives off a lot of ammonia when its first boiling. might have to warn the neighbours unless you want a hazmat unit arriving)
Once the ammonia given off has dropped off (you will know when by the smell) suspend the parts that you want to blue in the solution and cover ( to reduce the evaporation) and keep the solution on a rolling boil. Time depends on how blue (or black) you want your parts. Just keep lifting them out and checking until they reach the colour you want. Then rinse off and scrub under hot water. When cool give them a wipe with oil and you are done. Its very important the the parts are completely degreased before going into the solution. once degreased don't even touch them with you bare hands. Different steel alloys will give different colours as well so it pays to experiment a bit. Like any of these chemical treatments, they really show up any surface finish flaws, so if you want a really finish, it has to be good before you start blueing.
These days the biggest problem is actualy getting the ammonium nitrate. can be hard if you are not a farmer or a shot firer in the mines.
After a while the solution is spent as a lot of the water boils off. You could possibly add water to it (only when its cold) but I never did it (blueing) enough to worry about.
The cold, spent solution also makes a really good drain cleaner.

bollie7

Bollie7,
Looks like a good read. I'm going to have to get one of those booktab thingys.

Well I machined the back only just had enough room to fit it in the chuck backwards. Its now better than 0.005mm. If I need it any closer than that I'll start scrapping.
Now to catch the second one up so I can clean my lathe.

Stuart

Good to hear you got it fixed without it going the other way. Going by the pictures you got a good surface finish on it.

Dave

So I've drilled the mounting holes in the adaptor. To mount the chuck of course they have to be counter bored.
I can either use the boring head to machine to the pencil line 7mm deep so I can use an open ended spanner or machine in from the side 15mm deep with a milling cutter the Dia of the ring spanner or machine to the pencil line 15mm deep so I can use either spanner.
I really don't think it matters.
Anyone?

Stuart

What about socket head screws? That way the sides can be left untouched.

Dave

I'd thought about that but thought that maybe one day I would want to be able to make adjustments it with the chuck in place. I could use socket heads screws and cut some slots in the side for clamps to sit on?


Stuart

p.s. you pm inbox is full but you would know that already lol

Sorry I didn't realise and have deleted, I am sick of emptying it, it should be bigger. lol

I thought about being able to move it, but all my chucks are back plate mount so I can move them on that.
If you want that option I would go with using the boring bar to cut a neat semi circle out of it.
Just remember if a job has been machined in the lathe and transfered over to the rotary table it, the taper will need to be running true as thats the way it was machined.

Dave

But not the face plate.
I was thinking of some job where you might want some offset.(who knows what that might be.)
Having said that, its just dawned on me that the T-nuts for those mounting holes are pretty much at the end on the slots. You wouldn't get much offset with them before you have to move the clamps anyway.

I'm going with the semi circle. Maybe one day I will need it and surly there is enough bearing surface without it.

Stuart

You could just move the job on the face plate.
Saying that starting me thinking about those jobs where you run out of table because it's off set to the centre. Being able to move the adapter over to one side of the table with the face plate mounted to it would come in handy. I will have to measure the bolt holes to see if it can be mounted over to one side, or if I have to add more holes.

Your a bad influence, I have started to cut the steel up for mine. Just working out a mounting idea for the face plate with what I have laying around.

Dave