Thread: Brown & Sharpe #2 grinder restoration

Originally Posted by Greg Q

Greg on the Gold Coast.

sigh, border security is just so weak these days....

I swam across the Tweed in the dead of night. Plus I was wearing a hat made of banana leaves, which seems to be the border patrol's secret sign

Gregorio

Originally Posted by .RC.

Very nice work there Joe....

plus plus Joe i i get mine half as good will be happy.

Originally Posted by Greg Q

I swam across the Tweed in the dead of night. Plus I was wearing a hat made of banana leaves, which seems to be the border patrol's secret sign

Gregorio

I was trying to hatch a secret plan with Phil, to smuggle my OD/ID grinder into your furniture truck removing any useless stuff like beds or sideboards etc to make room, and get border security to remove it for me at the border when they arrested the notorious El Gregor... alas it never came off..

Just a little update - mainly for Greg and Mike - but also for anyone else interested.
I decided to mount my large old-school Telemecanique Altivar VFD on the back of the grinder (where all the pulleys and belt used to be). I've had this VFD on my mill for the past 20 years (and have now replaced it with a Huanyang 3kW one). It is a 1.5kW model with a frequency range of 5 to 70Hz. No control panel and no parameters....
Anyway, I found a suitable enclosure and tried it out.
The grinder has made it's first sparks! Now I was getting cocky and wound the wheel down to the magnetic chuck: just touching mind, and pushed the table across. Looks like the table slide and the chuck are still flat! Yippee!
The front bearing heated up quite quickly though
A little more research gave me a better handle on the ancient oil viscosity recommendation on the grinder: 100 secs Saybolt at 100 deg F can be actually converted to ISO 22 or SAE 20. So it seems to me that the thin oil sample kindly provided by RC may be running away too quickly. My next try will be with the ISO 10 Greg gave me. That should tell me if thicker oil reduces the heat gain. If so, I'll then go for some 20....
Next I took the motor off to check the drive and found it a little tight axially. That is easily adjusted.
I next surveyed the vertical slides. Greg, the front one is as straight as a die and the rear one has a few 10ths bow (worn hollow in the centre section). That matches the finding on the grinder at Phil's. Since Phil ground the rear spindle box cover, I now have a fitted master to scrape the sideways to. Anyway I spent about an hour today scraping and got it pretty straight and flat, maybe another hour to get bearing should do it.
I've also managed to win a German eBay Siemens 1/3rd Hp VFD (and my sister is visiting from Germany in a couple of weeks ) for the little 3phase gear motor I have planned to use to drive the table back and forth. A bit more design to go into the engagement mechanism yet, maybe a couple fo gears to cut....
Slowly making progress.....

Cheers,
Joe

Joe,

This is all too good!
All I had hoped for was an old grinder to do a handful of small projects and here it has become a thing of wonder!
Very nice to know it is in such caring hands.
More photos please when you can and as it progresses.

Michael

Joe, that is excellent work. Its interesting that the front vertical ways were flat...Without doing a survey I had expected the fugitive grit to have done its worst in wearing that slideway.

installed a vfd on his grinder purely for the slow starting/shutdown. He reckoned that the slow starting prevented the grinding wheel from being jarred out of perfect co-axial mounting and thus negating the need for re-dressing every time.

I don't recall if I mentioned it but Phil Steamwhisperer put me on to a firm in Greensborough that repairs that drip oiler for the spindle. It just needs the glass and a couple of seals.

Greg

@GregQ:
I have a suspicion that the rear spindle slide plate was somehow bowed and allowed the rear slideway to wear more than the front in the centre of travel. Anyway, the wear in the front slideways was visible (worn off scrape marks) but not measurable by me. So I rescraped the entire front, going a little heavier where the previous scraping was still visible and just to break up the surface to hold oil in the centre. Blueing showed not much difference before and after.
I already rebuilt the oiler - I used it in the trial run with RC's thin oil.....

A little more progress on the rear as well: spent a couple more hours scraping and blueing the rear slideways and the back of the spindle block (which sets the slide clearance). All good now! Moves nicely and tightly.
Very difficult to photograph....
A couple of pics of the painted and fitted enclosure for the VFD, the insides of the VFD and it's cover fitted,
I also found a nice period cast iron fuse box that I adapted for the VFD controls - complete with period speed potentiometer knob - modern E-stop button (just sitting on top there for the photo, not mounted where it belongs yet....)

I've also figured out how to mount the coolant system on the right hand side of the base. that way the entire machine is self contained.
More pics to come as the work unfolds....

IMAG0814.jpgIMAG0815.jpgIMAG0817.jpgIMAG0820.jpgIMAG0821.jpgIMAG0819.jpgIMAG0818.jpg

My thin oil Joe, It that the velocite 3 stuff? I think I sent Greg a litre of it... It is the stuff like Diesel.... ISO 2 grade

It was a grade Brown and Sharpe did I believe recommend, but only in the plain bearing model....

Roller bearings should probably be something slightly heavier at a guess.... ISO10 maybe?

Hi Richard. Yes it's the stuff like diesel. I used it in the (front) plain bearing only. The rears are high precision A.C. bearings. The whole spindle is specified for the same oil, just very different intervals - rear bearings just once a week....

I wired up and mounted the VFD 'control panel' just then and I think it looks just right....


Cheers,
Joe

Hi Joe,
Great work! I love seeing all that scraping, it just screams precision.

As for the coolant tank, i'm not sure why but grinders always seem to have big tanks. Mine is 100l, i think the smallest H&F machine with coolant is 50. There is no real way of filtering the coolant before it gets to the tank, so you will need a few baffles. The other thing to do is put a removable tin under the inlet, that way you can lift it out periodically with (hopefully) most of the sludge that seems to build up real quick in there......

Cheers,
Ew

So how does it grind Joe?

Originally Posted by Techo1

So how does it grind Joe?

It doesn't yet.... give me a bit more time to go over all the rest!
Greg warned me about the state of the table ways. I haven't even put a straightedge on them yet....
I will get to them shortly though

Originally Posted by Ueee

Hi Joe,
Great work! I love seeing all that scraping, it just screams precision.

Thanks, Ewan. It's as good as my skills allow - precision is of course a relative term

Originally Posted by Ueee

As for the coolant tank, i'm not sure why but grinders always seem to have big tanks. Mine is 100l, i think the smallest H&F machine with coolant is 50. There is no real way of filtering the coolant before it gets to the tank, so you will need a few baffles. The other thing to do is put a removable tin under the inlet, that way you can lift it out periodically with (hopefully) most of the sludge that seems to build up real quick in there......

Oh. My coolant system holds about 20 or 30 litres at a guess. It has 3 baffled chambers in it, with the pump sitting in the last and biggest one. I intend fitting a removable 'gutter' under the table drain. Thanks to your suggestion, I'll make that deeper than originally intended. I'll also be fitting a few magnets in the first tank chamber and a magetic 'filter' on the pump outlet. As it happens, Josh (Brobdingnagian) and I had a chat about this today and he made a suggestions using an electromagnet and a backwash valve.
I guess if my tank is too small I'll find out quickly. Or should I not even bother with that tank?