Small rotary table...........

[slim_boy_fat]

Bought this 4" rotary table on the 'Bay and it arrived today. A bit stiff in operation [ooh, er, Missus.....keep it clean, lads ] so I planned to strip it down and clean it all before having a go at removing the surface rust by electrolytic action (except the alu bits which I assume the scale(s) are made from - currently all soaking in paraffin so can't check for being magnetic ) [never tried it, but hey, life's a learning experience..... ]

I'm unsure how the table surface is held in the body, and after removing the locating Allen screw and collar in the bottom here

I can't for the life of me work out how I should proceed with separating the parts

I don't want to bash ahead [literally]and fubar the thing, anyone know the answer? It might be that a thorough clean, dip treat in the electrolytic solution and re-lube will do the trick, but Sod's Law dictates.......

 

[Fintray]

Not ever having separated one of these my first guess would be some gentle taps around the area of the table that the Allen screw came out of. A socket to fit inside the bearing and give it a tap.

 

[Digger6135]

Once the worm has been removed, it should press apart fairly easily if it has been left soaking in paraffin.

Digger6135

 

[slim_boy_fat]

Thanks, guys

.......... A socket to fit inside the bearing and give it a tap.

Once the worm has been removed, it should press apart fairly easily if it has been left soaking in paraffin.

Digger6135

So it should drift out upwards, using a suitable socket as the drift?

 

[Digger6135]

Thanks, guys





So it should drift out upwards, using a suitable socket as the drift?

Yes I would think so, there is another method you could try, that is a metal bar, with two holes at the same distance apart as the mounting holes, interpose a small distance piece, into the centre, then use two threaded bolts fitting into the mounting lugs, progressively tighten both till the table is jacked out, (easier to do than explain), but please do be careful not to over tighten and break the lugs.

Digger6135

 

[slim_boy_fat]

Thanks for that, as long as I'm pushing it in the right direction - never dismantled one of these [nor seen it done].

Will see what it looks like tomorrow after an overnight soak and a bit of a scrub.

I just found this YouTube video just now which helps a little [a very little] and you may as well jump to 9:00 in as the guy who built it can't initially recall how to dismantle it. Looks like it's just the bushing in my case which is tight, because I already have the worm drive out.

 

[slim_boy_fat]

Success!! Ta dah........

Drifted it out with a socket without too much 'banging'. The gear is brass, although looking before cleaning you'd never have guessed. Internals were all gummed up with what looked like copper grease + a few milling 'shards.

Now to set up electrolytic tank etc and leave overnight. It's painted with what looks like enamel [or Hammerite], any suggestions as to how best to strip it and start again with fresh enamel/paint?

 

[JohnRUFC]

Sandblasting? Just cover up anything that needs to hold a tolerance. We used to do it on a regular basis at work cleaning up lathe chucks!

 

[JohnRUFC]

You could always try something like Nitromorse but I'd imagine it's much more labour intensive.

 

[slim_boy_fat]

Blasting is out, I've only got a very small [10 litre?] compressor which came to me as a 'freebie' and it runs out of puff very quickly

I seem to recall reading that the formula of Nitromors was changed a while back due to having 'nasty' stuff in it, and it wasn't as effective before - is this right?

 

[DanielW]

Success!! Ta dah........

Drifted it out with a socket without too much 'banging'. The gear is brass, although looking before cleaning you'd never have guessed. Internals were all gummed up with what looked like copper grease + a few milling 'shards.

If you would have heated the metal up outside around the bearing it would have dropped out of its own accord,the same way it can be done for putting it back in place.

 

[DanielW]

I seem to recall reading that the formula of Nitromors was changed a while back due to having 'nasty' stuff in it, and it wasn't as effective before - is this right?

Yep,it still works but takes ages to strip paint.

 

[DanielW]

Dunk it in brake fluid?

 

[Wendelspanswick]

Blasting is out, I've only got a very small [10 litre?] compressor which came to me as a 'freebie' and it runs out of puff very quickly

I seem to recall reading that the formula of Nitromors was changed a while back due to having 'nasty' stuff in it, and it wasn't as effective before - is this right?

Yes Nitromors is pretty useless now, I use Starchem paint stripper, it's fully of lovely Dichloromethane.

 

[DanielW]

You'd be wise when putting it back together to change the bearing as well,chances are it will be also rusty?

Bearing is stamped with the type and size

 

[slim_boy_fat]

Bearing looks to be the rubber sealed type, although what immersion in cleaning solution will do to it, Heaven knows. Saw the markings so if need be a replacement won't cost the earth.

 

[ronan]

I seem to recall reading that the formula of Nitromors was changed a while back due to having 'nasty' stuff in it, and it wasn't as effective before - is this right?

Completely useless now, the good old busybodies in the EU got the nasty chemicals removed. Go to your local car paint shop and see if they have the good stuff.

 

[slim_boy_fat]

OK, what am I doing wrong? Sorted out the solution for the cleaning [2 gallons + two good desert spoons of washing soda], suspended the parts, connected up [positive feed to anode] and switched on battery charger.

After several hours, there's no sign of activity/bubbling, which from YouTube I understand that things should start happening very quickly. Charger is working OK when connected to my spare battery.

Only thing I can think of is I used MIG wire to hang the bits from....... Anode and 'cross hanger' are flap disced clean.

 

[DanielW]

Link to the vid please?

Copper plate in solution or hanging on side of bucket into solution.

 

[DanielW]

Erm! 'washing soda'? shouldn't that be Caustic soda? you'd be better off with fairy liquid.