Member postings for Michael Horner

When you use a DRO or a jig are you then not just a monkey turning the handle?

Just a thought.

Cheers Michael.

Hi Martin

The heat is from the current limit resistors (old technology). Will be fantastic in winter as a hand warmer.

I have just realised I have a stepper card of modern build driving the tool turret on my ORAC lathe, might just borrow that and see if the resonance and lost steps go away!

Hi David

First thing I did was check and lube everything up. You can turn both axis by hand and they feel free enough.

Cheers Mike.

Hi John

Thanks for that.

The Z motor is the one that suffers from resonance, X seems fine.

It's probably worth biting the bullet now, the heat from the stepper load resistors warms the whole of the back of the machine!

Cheers Michael.

Hi Martin

It has the original motors so around 36 years old. The power supply is 20 volts linear and it has Boxfords own stepper driver. No idea on the specs, I could measure the size of the stepper motors and get an approximation. What I am wondering is do the permanent magnets in the steppers lose their magnetism over time and hence their power.

Cheers Michael

Hi

I am converting a Boxford TCL 125 to Mach 3. I have got it working but it is losing steps on the Z axis. I have set the motor tuning to a low level, any lower and it wont be usable. Am I better off replacing the motor and controller?

TIA

Cheers Michael

Hi Geoff

Have you mounted your LEDs to a heat sink? I made some under cupboard lights out of LED strips and they deteriorated overtime which I put down to heat, The ones for my workshop I mounted on an aluminium stip and they seem to have lasted better.

Cheers Michael

Hi John

Take it out! In years gone by I would never have bothered.

Last month my wife's car was written off, not her fault. A transit van hit her on the passenger side, glad there were no passengers. Pushed her over a central kerb into on coming traffic! She needs a car for work and the payment ment she could get another car of similar / better spec quickly.

It was just before our holiday. It looked like I was a wife beater. Cheers Michael.

Try the home page nearly to the bottom on the right hand side.

HTH Michael.

I made an adapter to fit an existing tap wrench.

I put the lathe into neutral and turn the chuck by hand whilst pushing the tapping chuck into the work piece.

Once the tap is running true I slide the tailstock out of the way and remove the assembly from the chuck and put it into a keyless drill chuck and finish off. The bar I am tapping is usually around 12mm.

Cheers Michael.

Hi Graham

You have to be carefull with the trig functions on calculators because the default is radians not degrees.

HTH

Cheers Michael

Thanks John.

I will try that.

Cheers Michael.

Finished my lever tailstock today only to find that when applying pressure to the drill bit the thing twists. The clamp bolt is tight. Looks like I will have to redesign the linkage so that the force is along the bed.

Had more luck with my lantern chuck!

Cheers Michael.

Hi

Below is the reply from simply bearings.

Hello Michael

Thank you for your enquiry. I have checked the remainder of the 7201 bearings as ordered and the direction of thrust is against the non printed side. The axial load is to be presented to the non printed side. I hope this makes sense, these small ones often bring up this question, as they are generally too small to feature any visible physical difference in the races which is commonly found.

If you require further assistance then please do not hesitate to contact me as I will be more than happy to help.

Best Regards

Thanks for all the input.

Simply Bearings have not been in touch so I think I will send them an email perhaps refer them to this thread!

I don't fancy popping a seal off because if they are labled wrong I am stuck with them.

If they reply I will let you know what they say.

Cheers Michael.

Wow!

Thankyou for that Paul. You wouldn't happen to know what the contact angle is?

Just gone back and checked the link from Mike C and there is no mention of contact angle.

From your picture Paul, the ID side is the thurst side.

I will have to see what Simply Bearings come back with.

Cheers Michael.

Hi all

I have measured what I call the id side, the side with bearing number, 7201B. It is 27.96mm. This is in effect the seal od.

The other side measures 28.39mm.

Making the id side the thicker one and the thurst side. So in my design the two id's will face each other.

Just got to make up a locking coller to trap the spring to apply a little preload, find a motor to fit then try it out!

Thanks for all your help.

Cheers Michael

Hi Mike

That's where they came from.

Mine are the cheap as chips variety.

Just done a measurement as per the info and there is a slight differance.

Got to take the cat for a walk, I kid you not.

When I get back I will see if the measurment fit in with what I think.

Cheers Michael.

Hi Ketan

Best I could do.

Cheers Michael.

Posted by Michael Gilligan on 17/06/2015 20:55:11:

Posted by Michael Horner on 17/06/2015 20:39:46:

... in my application Michael G the writing will be on the inside because the spindle will be appling the pre-load.

.

Fair enough, Michael

I'm intrigued ... Do you have a picture ?

MichaelG.

Hi Michael

It is an embryonic toolpost spindle. I think the milling cutter will need to be reduced in length.

If it works I might try it as a milling spindle for engraving type work. The bearings are rated to 20000 rpm.

Cheers Michael

Hi Neil

Tried to measure with a digital caliper, result was inconclusive because of the curve on the inner edge.

Also tried to measure the displacement of the centre bit, again inconclusive. Not good on fiddily things.

Cheers Michael