Need Help!- 9x20 Alignment.

[Dougal]

Hi guys.

I have a 9x20 mill which seems to have alignment issues. I haven't taken the dial-gauge to it yet, but the headstock seems out of line with the bed.
For short items it doesn't matter, for longer items held with a live centre it doesn't matter, but for medium length parts which I need to drill it's a PITA.

I'm considering my options to fix it, the best one I've come up with is getting the spindle bearing holes rebored and fitting sleeves or bigger bearings. Are there any options I've missed?

[acondit]

There are adjustment screws on the bolts that fasten the headstock to the bed. You can use them to adjust the spindle alignment. And if it needs to be raised you can use shim stock to raise the headstock.

Also you need to be sure that you have the preload set correctly.

Alan

[Dougal]

Originally Posted by acondit There are adjustment screws on the bolts that fasten the headstock to the bed. You can use them to adjust the spindle alignment. And if it needs to be raised you can use shim stock to raise the headstock. Also you need to be sure that you have the preload set correctly. Alan

Aha, thanks. It looks like I need to take off some covers and guards to find these screws.

[acondit]

Here is some info I got from the 9x20 lathe group some time ago.

On the headstock picture the adjusting screws are shown as #14.

Alan

[ibuildstuff4u]

Before you mess with the headstock alignment I would make sure the bed is level and mounted correctly. You can easily create a twist in the bed if mounted wrong which will cause this problem. You need a good machinist level and test bar to properly set it up. The head is dialed in at the factory and I would not mess with it until you check out every thing else first because playing around with the head can be very time consuming and you can make the problem worse if it's the bed that is misaligned.

I have a 9X20 my self and have it set up pretty well, but still need a machinist level to fully dial it in. A good solid bench with leveling feet is needed too!

Dale P.

[Dougal]

Great information Alan, thanks again.

Dale, good points too. My lathe isn't bolted down, it just sits at the moment and this problem has persisted through three different locations. So I'm convinced that mounting is only the second or third alignment problem rather than the first.

Cheers
Dougal

[Dougal]

Well that was interesting.
I spent an hour with a dial gauge testing how round my bars of aluminium and stainless are.
After finding an acceptably straight piece, I found that the headstock and tailstock are as well aligned as my measuring gear can detect.

I also found my headstock bearings were loose and the compound slide jibs were too. Not loose enough to easily see. But loose enough to measure.
Adjusting those has made a huge difference.

[acondit]

Originally Posted by Dougal Well that was interesting. I spent an hour with a dial gauge testing how round my bars of aluminium and stainless are. After finding an acceptably straight piece, I found that the headstock and tailstock are as well aligned as my measuring gear can detect. I also found my headstock bearings were loose and the compound slide jibs were too. Not loose enough to easily see. But loose enough to measure. Adjusting those has made a huge difference.

For the longest time I couldn't get a good finish on any kind of turning. I tried everything but adjusting my spindle bearings, all to no avail. Finally, one day I decided to bite the bullet and check the adjustment of the spindle bearings. Voila, suddenly I was getting beautiful finishes on my turnings.

Alan

[ngr1]

Alan, can you please describe the process for adjusting the spindle bearings?

Thanks!

[acondit]

Originally Posted by ngr1 Alan, can you please describe the process for adjusting the spindle bearings? Thanks!

Here is some info I collected from the 9x20Lathe group. It is just a series of e-mails that I put together in a pdf but they helped me.

Alan

[ngr1]

Thanks Alan!

[acondit]

Originally Posted by ngr1 Thanks Alan!

You're welcome.

Alan