Denford Triac Spindle making an odd noise. Bearings at fault?

[m_c]

It does sound like the belt is flapping around, but I'd be wondering why, as unless somebody has recently been slackening the motor of, it shouldn't suddenly become slack. However the spindle does seem a bit noisy in general, but that could just be the video.

Also it heating up that quick is not a good sign. I'd be taking the motor of, and giving the spindle a spin by hand to see how it feels. I'd also be checking for play with a DTI, but to check for correct adjustment, you really have to take the cylinder and the top support housing/bearing of, as the top bearing will mask any play in the main spindle bearings.

[Chaz]

It does sound like the belt is flapping around, but I'd be wondering why, as unless somebody has recently been slackening the motor of, it shouldn't suddenly become slack. However the spindle does seem a bit noisy in general, but that could just be the video.

Also it heating up that quick is not a good sign. I'd be taking the motor of, and giving the spindle a spin by hand to see how it feels. I'd also be checking for play with a DTI, but to check for correct adjustment, you really have to take the cylinder and the top support housing/bearing of, as the top bearing will mask any play in the main spindle bearings.

The reason for this is that the mounting system is not ideal. The bolts are also not locktighted (is there such a word) which means that they can and will come lose.

Ive seen another way to do a servo mounting, which is the extend a shaft down and keep the motor mounted higher up. When I did this mod (this is my old machine), I opted to do something to get me running as my DC motor had died. Multiple ways to deal with the bolts coming lose (there are only 2), ideally 3 or 4 if possible.

The bearings might be tired, perhaps if the lot is being stripped / sorted, a new motor mount could be machined and used that is better than what I had originally put in place.

[m_c]

That'll explain why it's come slack then. IIRC the original mount used 3 bolts, as the other corner is cutoff due to the head casting shape.

To the OP, if you search for my Triac retrofit thread, you'll find how I made a new spindle motor mount to fit a servo, along with some details to rebuild the spindle with new bearings.

[Chaz]

That'll explain why it's come slack then. IIRC the original mount used 3 bolts, as the other corner is cutoff due to the head casting shape.

To the OP, if you search for my Triac retrofit thread, you'll find how I made a new spindle motor mount to fit a servo, along with some details to rebuild the spindle with new bearings.

Ah, that was your mod, wasnt it? Yes, 3 bolts but when I did the bracket I could only get to 2, as the motor effectively is too big to fit. Your idea is better but needs more work.

[andy_con]

Also the spindle bearing is 20 odd years old, mine went and i had to change it.

Bearings don't last forever

[m_c]

My mod was quite a bit of work. I think the lathe work alone took about 3-4 hours, as it was a big lump of bar to hollow out.

Now I've had time, this post gives the process of renewing the bearings - http://www.mycncuk.com/threads/10344...8817#post88817

And the spindle motor mods start a bit further down that page - http://www.mycncuk.com/threads/10344...9732#post89732

[Lieutenant Swarf]

Thanks to everyone who has replied, it really is very much appreciated.

Chaz-Tightening the two bolts holding the motor has eliminated nearly all the noise for now. However the top bearing support is still getting hot. Thanks very much for your rapid response and friendly advice.

MC- Thanks I will take a look at those links you have posted and hopefully get some ideas about a long term solution to mounting the motor.

Andy- I looked at an old post of yours on the Denford Forum and hoped that you might have some good advice. Did you replace your bearings like for like or did you upgrade when you made the swap?

Thanks again guys

[Lieutenant Swarf]

My mod was quite a bit of work. I think the lathe work alone took about 3-4 hours, as it was a big lump of bar to hollow out.

Now I've had time, this post gives the process of renewing the bearings - http://www.mycncuk.com/threads/10344...8817#post88817

And the spindle motor mods start a bit further down that page - http://www.mycncuk.com/threads/10344...9732#post89732

Wow MC that is outstanding work on that Mod! Really inspiring stuff.