Question: Turntable roughness

[Ste82]

Hy all!
I have a big question...i've just bought a GRS tourntable, it is much more stable than a lazy suzy but i was expecting a much more smoothnes, it is much harder and noisy to spindle around than the bearings of the vise, and if i try to spin it quite hard, it makes less than a quarter of rotation (the brake system is off).
Here in Italy there is no one to compare it, so if some of you could tell me if it is normal or if i have to do some maintanance to the bearings!?
And sorry for the bad english! :thinking:
Stefano

 

[Arnaud Van Tilburgh]

I had to adjust the brake system spring a bit, as the table didn't run smooth even when the tension on the brake off. The leather kept touching the table until I adjusted it.

arnaud

 

[Ste82]

Thanks Arnaud,
But i had completly take away the brake system!
I dont know but it is quite noisy, looks like the plastic balls need some lubricant????

 

[silverchip]

I recently took mine apart and discovered that they use ceramic ball bearings.Mine was rough and getting worse,So since I had the appropriate size steel ball bearings, I just replaced the ceramic ones and used a little bearing grease in the groove.TA DA!!!!! it works very well for me!!!!

 

[scott99]

Hi, I have a GRS turntable and it runs super smooth. You might have some metal filings or grit in the bearing track. :thinking:

My table got rough and that was my entire problem, rather than taking the table apart I flushed it out with some WD40 using a thin plastic applicator (comes with the can of WD40). I suppose any oil based cleaner would work. To clean,spray, rotate,spray again, continue until the table runs smoothly. then you will probably have to set it on its edge for a while so the excess oil drains away.

If its like mine you will be surprised at all the chips that come out, :clapping:

All this assumes that you have not dropped the table and bent the bearing shaft. :thinking:

I then made a cloth cover that hangs over the edge of the table so as to keep the chips out. It just sits under the vice and is just big enough to fall over the edge of the table and should rotate along with the table.

Scott99

 

[Ste82]

Thanks guys!
You are fantastic!:clapping:
The turntable is new and never used or dropped..at least by me!
I think you're right, i'll try to open it and clean or change the ball bearings...

Ste

 

[Fred Bowen]

I had trouble at first, but squirted some powdered graphite between the tables and that smoothed it out.

 

[Ste82]

Ok...
I've tried to spray some WD40 btwn the plates...only slightly better results...
But can you confirm me that it is quite noisy when spinning??
Stefano

 

[Brian Marshall]

WD40 is a mistake. WD stands for "water displacement". Go look it up...

It works as a lubricant while fresh, turns into a sticky varnish as it ages - and finally freezes the bearings.

A student once sprayed the stuff into some delicate pantograph bearings. We didn't use the pantograph for a year or so. Had to take out the bearings and replace them all.


Brian

 

[KCSteve]

The GRS turntable should not be noisy when it turns. Something must have happened to yours during shipping.

A tip for when you open it up: get a large, clear plastic bag (like the ZipLock brand bags) and take it apart inside the bag. Once you see all the little balls roll out (and they almost certainly will) you'll be glad to have them trapped in the bag. There's a spacer disk inside that keeps the balls in place so you have a way to make sure you're not missing any.

 

[bildio]

I've had mine a couple of years, but it doesn't get much use. I removed the vise and gave it a spin. It makes a uniform noise throughout the rotation, but turns smoothly. If this topic hadn't come up, and I gave it spin, I don't think it would have registered with me as other than its normal sound.

 

[Sam]

Oil will only foul up the works. Take it apart by turning it upside down and lay a towel over it to catch the retainer. Then use two screwdrivers to gently separate the disks causing the retainer to pop off. Clean really well with spray furniture polish (Lemon Pledge works great!) and reassemble. Using oil will cause the plastic spacer to stick to the disks and create drag. I clean mine about once per year.

The balls are nylon, not ceramic.

 

[Roger Bleile]

Stefano,

I don't know what part of Italy you live in but if you are near Gardone, the only engraver that I know there who uses a microscope is Stefano Pedretti. Perhaps he has some advice for you. Here is his contact information:
Via Matteotti, 129 25063 Gardone Val Trompia (Brescia) Italy
Tel +39-030-832310 Fax. +39-030-8916217
E-mail: info@pedretti.com

Saluti,
Roger

 

[monk]

never a problem for me. i have it & the grs positioning vise. just below the tightening screw, i taped an apron all around. made of slippery, light weight, nylon type- the kind barbers use. the apron doesn't hinder rotation or re-positioning. it hangs down about 18" that protects the jack screw as well. once it's cleaned out, the apron gives full chip protection-- except the bleepin chips that get into my shoe !

 

[rod]

Stefano,

Your english is excellent!

I also had some friction on my GRS turntable, here is what worked for me.

By the way, the balls are ceramic, not plastic.

Lift off your turn table, carefully turn it upside down, while holding top and bottom so the balls do not come up

Once it is upside down, you can remove the plate, as the other plate has a groove in it, and balls will stay in the groove.

Remove the plastic separator disc, that keeps the balls apart, for me this causes too much friction.

I used short pieces of brass round rod, say 3mm dia approximately, about 25mm long between each ball, and replace the steel disc, and again carefully turn the unit back to the correct side, and it should work smoothly with less friction?

It is also possible to get metal chips in the balls, and this of course interferes with the smooth running.

Rod

 

[Ste82]

I can only say a BIG thanks to all of you!
I will try to disassemble the turntable and ill let you know the results...i hope i do not have to wait for a replacement from US..it's quite a long trip!!
Stefano

 

[Beathard]

Take some photos and post them. It would be nice to see the documented process.

 

[Ste82]

Ok, I did it!
Like Beathard asked i tried to take some pictures of the process, forgive me for the quality but the camera was a cell phone....:beatup:
I've started turning it upside down and covering with a cloth(thanks for the tip Sam!), i covered also the tips of the flat screwdriver's to avoid scratches betwen the plates, then i had turned the screwdriver separating the plates and popping out the little retention ring

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This is what i founded inside...part is my wd40 spray the other i think is old grease (maybe the turntable was an old stock, in Italy really few people use it and it could be years old...who know's!!)

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i've cleaned everithing with a degreaser:

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now i reassembled the two plates, and to insert the little retention ring i had arrange with the hole of a tweezer (i hope it is the correct term!) and a soft hammer, in the photo it is barely visible...

[/IMG]

Now the turntable is much more easy to spin, the problem i think, was the stiki grease...it is still a little rough and looking closely to the plastic sphere i've noticed that they look stamped and they still have some little pins of plastic that probably create the noise and little roughness, quite sure it will desappear with use, smoothening the plastic balls

This is my experience with the turntable, i hope it can help someone!
Again a big thank to all the people that helped me...

Stefano

 

[Sam]

As you discovered, oil makes a mess of the turntable and causes the plastic spacer to drag making it extremely difficult to turn. Keep it dry and clean.

 

[Beathard]

Thank you for the documentation. Now we will know what we are getting into when he have the same issue.