Grinder balance

[qwertyu]

I used to use the buffing wheel directly on my grinder's arbor (for unicorn method) but now I have 2 buffers which I want to switch out occasionally to polish some plastic. Therefore I got one of those tapered spindles (its a Josco one I had from total tools) but its not really balanced and now there is HEAPS of vibration.

Is there anything I can do to remedy this?

VID_20210918_105144.mp4 - Google Drive (https://drive.google.com/file/d/1Yc1K1s2qXt7aPL-LG4NQO4d-_4DhWeNP/view?usp=sharing)

VID_20210918_105223.mp4 - Google Drive (https://drive.google.com/file/d/1Y_LZsYhrTnF0E6huM6BmGHiKkE-WT7jc/view?usp=sharing)

Not sure how well these videos show it

[China]

Can't see any problem? what is like when running, without a mop on it, Josco is a low end product ( i.e. Rubbish )

I would consider throwing them out and replacing with this brand

https://www.pretooling.com.au/products/tapered-spindles-for-straight-grinders

[BobL]

The buffer spindle does not look like it's tight up against the buffing wheels bore.
There should not be any gap at the the of the green arrow or teh wheel can easily throw itself out of balance.
501261

Have you got the buffing wheel on the right way?

If the other side is tight up against the plastic bugging wheel flange you may have to open up the hole so teh wheel goes further onto the spindle.
Usually use will dress the wheel but you might also need to actively dress the wheel. I use a thick hacksaw blade - teeth side careully brough up against the towards the wheel rim

[qwertyu]

Can't see any problem? what is like when running, without a mop on it, Josco is a low end product ( i.e. Rubbish )

I would consider throwing them out and replacing with this brand

https://www.pretooling.com.au/products/tapered-spindles-for-straight-grinders


Lots of vibration - basically entire bench shapes and things slide off the top lol

Hmm will look into that product



The buffer spindle does not look like it's tight up against the buffing wheels bore.
There should not be any gap at the the of the green arrow or teh wheel can easily throw itself out of balance.
501261

Have you got the buffing wheel on the right way?

If the other side is tight up against the plastic bugging wheel flange you may have to open up the hole so teh wheel goes further onto the spindle.
Usually use will dress the wheel but you might also need to actively dress the wheel. I use a thick hacksaw blade - teeth side careully brough up against the towards the wheel rim

How can you tell which way the wheel goes on?

I dont think the wheel is the problem - the tapered spindle without the wheel you can see the centre of the spindle wobble as it spins

The hole in the wheel is huge because I drilled I drilled it out to fit onto the arbor direct so the other side is tight. Maybe I should taper the hole....

How do you put a wheel onto the spindle? I did it by turning the grinder on and gently placing the buffer on and letting the machine grab it and spin up the spindle until it stops

[BobL]

How can you tell which way the wheel goes on?
I don't think the wheel is the problem - the tapered spindle without the wheel you can see the centre of the spindle wobble as it spins
Have you tried the grinder with just the new spindle without the buffing wheel - that should have been the first thing to do.


The hole in the wheel is huge because I drilled I drilled it out to fit onto the arbor direct so the other side is tight.
Almost certainly that will be (part of) the prob.


Maybe I should taper the hole....
Yep but you have already drilled it out so maybe replace one flange with a flange with a smaller hole.
See below


How do you put a wheel onto the spindle? I did it by turning the grinder on and gently placing the buffer on and letting the machine grab it and spin up the spindle until it stops
Correct BUT spindle should make firm contain with holes in both flanges.

Here is a thread showing how I take two 4 fold Scothcbrite wheels and turn them into an 8 fold wheel.
You might get some useful ideas about how to rebuild the flange for one with a smaller hole.
Fatter Scotch-Brite wheels (https://metalworkforums.com/f65/t202504-fatter-scotch-brite-wheels)

[Oldmeadow]

I recently got a Josco tapered spindle from Bunnings as the package contained both 1/2" and 12mm options. I measured my grinder arbor to be 1/2" but I wasn't 100% sure.

Anyway, it is 1/2" but upon loading, the spindle had a more pronounced wobble than yours. Surprisingly, it actually ran ok. The buffing mop that I had could be re-loaded onto a point of balance so that it ran true.

I've ordered a whole array of buffing mops etc from Casweld and another tapered spindle. I'll place it on the opposite arbor in case that side is more balanced.

If you're interested, I can let you know how I go RE wobble with a better quality spindle.

For you, I'd agree with BobL and first try to modify the hole so that the mop can properly seat onto the spindle. Perhaps the plastic part on the wider side of the taper can be widened (if not, you'd need to replace one side or add on a new piece with a smaller hole)?

[qwertyu]

Yep would be good to see how you go with the other spindle

Here is the grinder turning on with just the arbor
VID_20210921_171209.mp4 - Google Drive (https://drive.google.com/file/d/1ZoikYi50gHe9hwec5qeu6y6toPb6Z_iJ/view?usp=sharing)

and then with the tapered spindle
VID_20210921_171446_01.mp4 - Google Drive (https://drive.google.com/file/d/1Zmi5lfhwJF_yMC5tFiPC-kY11v2Fuxlb/view?usp=sharing)

You can really see how much wobble there is now with the camera on the tripod! The buffing wheel just amplifies the vibration. I also have a smaller 150mm 40 fold cloth wheel - still lots of vibrations.

So I am inclined to think its the spindle... The other side of the grinder has a CBN wheel and I am pretty sure that is balanced - when I look at the wheel spinning it looks really smooth. Though I never got one of those washers you can get to self balance it...

I tried tapering the hole on the mop for better contact but the bigger side wouldve been too big and hit the nails on the plastic. I will just get a new mop.

[BobL]

Yep its the spindle - I would take it back and get a replacement - no amount of finessing the wheel or balancing washers is going to fix it.
Show the vendors the videos.

[Oldmeadow]

I received the Caswell spindle today.
:hpydans:
You'll find them at the bottom of this page. (https://www.caswellplating.com.au/store/store.php/categories/adaptors-and-extensions-tools)

It took 1.5 business days between ordering and courier arrival which is really good considering Auspost at the moment.

There is a night and day difference. I'm really happy with it as well as the rest of the order. Rather than screwing onto the threads and only being able to seat onto one position, the spindle slides over the arbor and is fixed in place with grub screws which allows fine adjustments for perfect balance. I like that the spindle can slide over a plain shaft as I'm on the lookout for a powerful treadmill motor with adjustable speed.

The spindle has a finer tip and the thread is a lot 'sharper' which allows stronger bite. That could possibly help with your wheel.

[China]

Take it back and get your money back, and replace with a better type again Josco are rubbish