Brown&Sharp No2 surface grinder any good?

[Eyecon]

Hello All,
I’ve been on the lookout for an affordable surface grinder for my small garage shop and I can’t really afford (money and space) any of the import ones I could find online. I found a Brown and Sharp No. 2 surface grinder which appears to have a small enough footprint to fit in my space. Machine is obviously old and appears to be in decent condition(still haven’t seen it) but will require some work including major cleanup and possibly replacement of the 3 phase motor. I don’t have much experience restoring old machines other than my grandfather’s machinist hand and metrology tools, but I’m willing to take this on as a fun project and end up with a decent surface grinder. Is this a good idea? I don’t know much about surface grinders but will probably be able to look for signs of extreme wear if I go to take a look.

 

[DavidR8]

I have a friend in CA with a B&S surface grinder. Bigger than a #2 mind you but he says the quality is excellent.
They came with two motor arrangements; belt drive with the motor in the cabinet and direct drive. If it it's a direct drive and the motor needs replacement be prepared for a big shock as they are not cheap.
Surface grinders by their nature tend to end up pretty grungy. My 1966 Parker Majestic spent it life in a tool and die shop where it was well maintained but it was still a dirty, gritty mess to clean up.

That said, I think @Dabbler has a B&S surface grinder and will likely have some good advice.

 

[Xyphota]

I know nothing about surface grinders, but just a comment about the motor replacement; Does it need replacement because it is shot, or because you don't have a 3 phase power source? If it is the latter, a VFD will turn whatever single phase power you have available into 3 phase and be cheaper than a replacement motor.

 

[Eyecon]

I know nothing about surface grinders, but just a comment about the motor replacement; Does it need replacement because it is shot, or because you don't have a 3 phase power source? If it is the latter, a VFD will turn whatever single phase power you have available into 3 phase and be cheaper than a replacement motor.

The motor is in "working condition" according to seller, I was thinking I could run it on one of the cheap huanyang VFDs I have and replace it with a modern motor when it dies. I'm guessing these old motors are the bronze bushing kind and I'm not even sure what kind of power it draws..I read any where between 1 to 2 HP on the B&S No. 2. I also don't know if the grinder is the belt driven or direct drive version.

From @David_R8 comments, I think it's worth the 1 hour or so drive to at least go see it.

 

[DavidR8]

It is very likely it has bearings not bushings because it is a high precision spindle and bushings are not sufficiently precise.

 

[Eyecon]

I have a friend in CA with a B&S surface grinder. Bigger than a #2 mind you but he says the quality is excellent.
They came with two motor arrangements; belt drive with the motor in the cabinet and direct drive. If it it's a direct drive and the motor needs replacement be prepared for a big shock as they are not cheap.
Surface grinders by their nature tend to end up pretty grungy. My 1966 Parker Majestic spent it life in a tool and die shop where it was well maintained but it was still a dirty, gritty mess to clean up.

That said, I think @Dabbler has a B&S surface grinder and will likely have some good advice.

Is there anything specific that I need to be looking at in terms of wear or other things that affect accuracy on the machine when I go to inspect it? The asking price is CAD1500 but I don't want to end up with a 2000lbs useless piece of cast iron

 

[Eyecon]

It is very likely it has bearings not bushings because it is a high precision spindle and bushings are not sufficiently precise.

sorry I meant on the motor specifically...AC motors I saw online from the 30's and 40's tend to be very simple and are usually bushing based....I could be totally wrong

If the motor is running and I can run it on a VFD I'm totally going to if I end up getting this machine...I just don't have very high hopes

 

[Dabbler]

replacement of the 3 phase motor.

They came with two motor arrangements; belt drive with the motor in the cabinet and direct drive.

Is there anything specific that I need to be looking at in terms of wear or other things that affect accuracy on the machine

I have a B&S Valuemaster 612, a little bigger than a #2.

The motors that are included with a surface grinder are usually balanced, and not regular run-of-the-mill motors. That being said, you can still do good work if you put a 1Phase motor on it. You surface quality will suffer, but you can still hit your dimensions.

What will make the purchase worthless is if the main spindle bearings need replacing. On mine just the 2 Abec7 bearings are just north of 2800US$
For less accuracy and surface finish, you can go ABEC5, but still be prepared for north of 400$, at least for the size my grinder uses.

You want to run it, and it should be quiet. Certainly no slowly rising harmonics that falls off with a period of 2 seconds or greater... Check the ways. If scraped, there should be scrape marks. If ground, there should be no scoring. Every hand crank should be easy to move in both directions. The chuck should not have smiles or crash marks on it. Check for rust where precision surfaces should be. That's about it. Check for side play if a grinding wheel is mounted.

Every one of these becomes a price modifying thing if present. A 2000$ grinder can become 200$ grinder if every one of these checks fails.

All the best!

P.S. I ran my grinder under power and ground a coupon 1" X 2" and checked finish. I turned it over then ground again, checking for end-to-end dimension. on 2" it should be less than 1 tenth of a thousandth of an inch difference, even without coolant and an undressed wheel. More than, say, 3 tenths, and you should only buy it if you know how to rebuild surface grinders.

 

[DavidR8]

+1 on the silent running. Running my Parker Majestic off a VFD I could hear the VFD over the motor. Quietest machine of any sort I have ever heard.

 

[Eyecon]

I have a B&S Valuemaster 612, a little bigger than a #2.

The motors that are included with a surface grinder are usually balanced, and not regular run-of-the-mill motors. That being said, you can still do good work if you put a 1Phase motor on it. You surface quality will suffer, but you can still hit your dimensions.

What will make the purchase worthless is if the main spindle bearings need replacing. On mine just the 2 Abec7 bearings are just north of 2800US$
For less accuracy and surface finish, you can go ABEC5, but still be prepared for north of 400$, at least for the size my grinder uses.

You want to run it, and it should be quiet. Certainly no slowly rising harmonics that falls off with a period of 2 seconds or greater... Check the ways. If scraped, there should be scrape marks. If ground, there should be no scoring. Every hand crank should be easy to move in both directions. The chuck should not have smiles or crash marks on it. Check for rust where precision surfaces should be. That's about it. Check for side play if a grinding wheel is mounted.

Every one of these becomes a price modifying thing if present. A 2000$ grinder can become 200$ grinder if every one of these checks fails.

All the best!

P.S. I ran my grinder under power and ground a coupon 1" X 2" and checked finish. I turned it over then ground again, checking for end-to-end dimension. on 2" it should be less than 1 tenth of a thousandth of an inch difference, even without coolant and an undressed wheel. More than, say, 3 tenths, and you should only buy it if you know how to rebuild surface grinders.

Thank you for all the information! I’m going to go see the machine on Thursday and the seller says it runs well. Should i take some measurement tools with me or would that be inappropriate? Sorry for the dumb question but I never bought a vintage machine before and as mentioned have no experience with surface grinders at all

 

[DavidR8]

Thank you for all the information! I’m going to go see the machine on Thursday and the seller says it runs well. Should i take some measurement tools with me or would that be inappropriate? Sorry for the dumb question but I never bought a vintage machine before and as mentioned have no experience with surface grinders at all

The last bit of Dabbler’s post is super relevant.
I’d look up Suburban Tools videos on grinding. It’s a bit of a black art but I was able to produce decent finishes with some practice.

 

[garageguy]

If you haven't already done so, check Vintage Machinery for manuals. They have a download site and you can make a donation to help keep it up.

 

[Eyecon]

The last bit of Dabbler’s post is super relevant.
I’d look up Suburban Tools videos on grinding. It’s a bit of a black art but I was able to produce decent finishes with some practice.

So bring a small blank with me to grind? I’ll definitely check out those videos before going to see the machine. Thank you!

 

[DavidR8]

So bring a small blank with me to grind? I’ll definitely check out those videos before going to see the machine. Thank you!

Yup and a micrometer that will read tenths if you have one.

 

[Eyecon]

Managed to find the manual for the No. 2 surface grinder, apparently it’s normally a plain bearing spindle machine. Is this a bad thing for a surface grinder?

 

[DavidR8]

Managed to find the manual for the No. 2 surface grinder, apparently it’s normally a plain bearing spindle machine. Is this a bad thing for a surface grinder?

Not in my eyes if it been well maintained.
@Dabbler?

 

[DavidR8]

Also @Eyecon

Yet another B&S No. 2 surface grinder.

Picked this one up in Arizona. Brown & Sharpe No. 2 Surface Grinder. Serial number 9803. What's the approximate age? From reading other threads on various fora I know it's pretty far before WW2 and quite a ways after WW1. Brown & Sharpe #2 grinder - a set on Flickr Upon lifting the table...

www.hobby-machinist.com

 

[Eyecon]

Thanks again for all the info…looks like there are several variations of this machine depending on the year. I’m also concerned about the motor which the seller says is a 600V 3 phase. None of my vfds can do more than 380v line voltage so I’m not sure if this unit will be usable in my shop unless I change the motor. Also to @Dabbler’s point about specialty motors for SG spindles , I guess that’s for direct drive and I’m not sure if this unit is the direct drive or the belt driven version. I’ll go and take a look anyway if for nothing else to learn…seller seemed friendly on text messages

 

[DavidR8]

Thanks again for all the info…looks like there are several variations of this machine depending on the year. I’m also concerned about the motor which the seller says is a 600V 3 phase. None of my vfds can do more than 380v line voltage so I’m not sure if this unit will be usable in my shop unless I change the motor. Also to @Dabbler’s point about specialty motors for SG spindles , I guess that’s for direct drive and I’m not sure if this unit is the direct drive or the belt driven version. I’ll go and take a look anyway if for nothing else to learn…seller seemed friendly on text messages

I've only had 240v 3-phase machines so I can't offer much help on that front but @Tom Kitta can likely shed some light on 600v 3-phase options.
And yes it's worth a look.

 

[Dabbler]

Multitap transformers are available to boost the 3 phase voltage. Most of the smaller SGs used 1HP motors so the required transformer would be very small. On that small a set up, it would be practical to put the transformer on the output side of the VFD, a practice not recommended in larger motors.

Belt drive SGs by B&S used specially balanced motors to minimize vibration.