WTB: Nice condition small(ish) auto surface grinder

I’ve been scouring eBay and used machinery sites for quite a long time trying to find something that catches my eye, so figured I’d reach out to you guys. I’m in need of a nice auto surface grinder. Not particularly partial to brand, but I’ve been looking at Mitsui, B&S Micromaster/Techmaster, and Okamoto mainly as they seem to be great machines. Auto downfeed is preferred, but not imperative.

Let me know what you have!

Condition is king on surface grinders, you can find some older machines that are pristine. Personal tryout is important to see that the spindle is good, and it will grind flat to .0002 or so.. Good to take your own diamond, grind-stock, and a flat parallel for the test. Auto-down feed is mostly used for rapid and time-saving. Auto down for grinding is less common. Size is the footprint, and part size grinding ability. There are additional good/Ok names like Harig, Reid, parker, Kent, Ko Lee, Landis (all the major brands.)

Morgantown, WV is not a good area because of only a few SG for sale.
Some ball way machines are subject to grit contamination from grits getting in from the collum side, all grinders are subject to air hose blowing, being run with low oil, and can be worn out from that poor practice.

michiganbuck said:

Condition is king on surface grinders, you can find some older machines that are pristine. Personal tryout is important to see that the spindle is good, and it will grind flat to .0002 or so.. Good to take your own diamond, grind-stock, and a flat parallel for the test. Auto-down feed is mostly used for rapid and time-saving. Auto down for grinding is less common. Size is the footprint, and part size grinding ability. There are additional good/Ok names like Harig, Reid, parker, Kent, Ko Lee, Landis (all the major brands.)

Morgantown, WV is not a good area because of only a few SG for sale.
Some ball way machines are subject to grit contamination from grits getting in from the collum side, all grinders are subject to air hose blowing, being run with low oil, and can be worn out from that poor practice.

Click to expand...

What does that mean? I get having power feed in X will save the arms and shoulders on a big grind job, but being able to set to feed down is the cats meow! Think Okamoto with the digital controls, sparkout, creep feed, down at every Y direction change, etc etc...

super95awd said:

I’ve been scouring eBay and used machinery sites for quite a long time trying to find something that catches my eye, so figured I’d reach out to you guys. I’m in need of a nice auto surface grinder. Not particularly partial to brand, but I’ve been looking at Mitsui, B&S Micromaster/Techmaster, and Okamoto mainly as they seem to be great machines. Auto downfeed is preferred, but not imperative.

Let me know what you have!

Click to expand...

Every SG I have ever run, or even looked at for sale, has numbers on them.
Now, as we are a technical bunch around here, we doo like to use numbers
to better help answer your question.

Re:[Auto-down feed is mostly used for rapid and time-saving. Auto down for grinding is less common.[What does that mean? ]
likely the op will find 1 in 20 used machines with auto down feed.

I don't use the term descriptions xyz for grinders because some manufacturers have that differently. I just use long-travel, cross and down.

Digger->Every SG I have ever run, or even looked at for sale, has numbers on them.
like 5-10 6-18 36-70

michiganbuck said:

Condition is king on surface grinders, you can find some older machines that are pristine. Personal tryout is important to see that the spindle is good, and it will grind flat to .0002 or so.. Good to take your own diamond, grind-stock, and a flat parallel for the test. Auto-down feed is mostly used for rapid and time-saving. Auto down for grinding is less common. Size is the footprint, and part size grinding ability. There are additional good/Ok names like Harig, Reid, parker, Kent, Ko Lee, Landis (all the major brands.)

Morgantown, WV is not a good area because of only a few SG for sale.
Some ball way machines are subject to grit contamination from grits getting in from the collum side, all grinders are subject to air hose blowing, being run with low oil, and can be worn out from that poor practice.

Click to expand...

Thanks for the thorough reply! Ya, digging through the heaps of them available looking for something that hasn’t just gotten a nasty coat of paint slapped on it to sell it is exhausting. That’s why I was hoping one of you guys would just have a perfect one tucked away in a garage that you didn’t need!

And yes, the Morgantown area is a black hole for anything manufacturing related. I’ve pretty much come to terms with having to take a leap of faith on any used machinery based on pics and videos.

digger doug said:

Every SG I have ever run, or even looked at for sale, has numbers on them.
Now, as we are a technical bunch around here, we doo like to use numbers
to better help answer your question.

Click to expand...

Of course! I’ve been looking anywhere from the 6-18’s up to around the 10-30 range.

super95awd said:

Of course! I’ve been looking anywhere from the 6-18’s up to around the 10-30 range.

Click to expand...

Of Course ! please check my quote of your OP....no sign of any dimensions listed.....

Mind reading we still can't doo....

I have run a few programable SG but for my kind of work mostly one-ups of high precision, and simple parts, and duplicating parts that were often hot (need it now) jobs I found myself still standing at the machine. Most often running by manual would be just as fast. DROs are handy on a SG.

Yes, I can see in a semi-production environment programmable and/or automatic could be an asset.

Running tool and cutter work the programmable was extraordinarily faster for most work than by hand.

You might state the nature of your work.

Programable TC grinders had probes the could check wheel wear and then run a part in tenths, That could be an aid in semi-production SG work.

If I designed a programmable SG I would add down feed increments at both or just one end of long-travel..and at one or both ends of the cross. may have had that on a Shipley.. I cant remember now but think not..

michiganbuck said:

I have run a few programable SG but for my kind of work mostly one-ups of high precision, and simple parts, and duplicating parts that were often hot (need it now) jobs I found myself still standing at the machine. Most often running by manual would be just as fast. DROs are handy on a SG.

Yes, I can see in a semi-production environment programmable and/or automatic could be an asset.

Running tool and cutter work the programmable was extraordinarily faster for most work than by hand.

You might state the nature of your work.

Programable TC grinders had probes the could check wheel wear and then run a part in tenths, That could be an aid in semi-production SG work.

If I designed a programmable SG I would add down feed increments at both or just one end of long-travel..and at one or both ends of the cross. may have had that on a Shipley.. I cant remember now but think not..

Click to expand...

I have a particular product that I need to grind small parts for, 2.25” OD. I make them in batches of about 200 and they need ground both sides. I figured something with downfeed I could just get set up and walk away while it ran a full magnet of them.

Here is a kent programable SG but it is in California(Oxnard). (kent is a decent machine.)
2010 KENT USA Rotary Table Surface Grinder Programmable KGS 1020SD 10" x 20" | eBay

But the photo does not show a rotary table machine???
2.25" od by x.xxx"
Some/most programmable stop SGs give a take-off amount, so you start at perhaps + .010 going to zero(if you deem that +.10 the high part and grind a little air, then grind parts to size by taking off a specific amount. But having a high variance in rough size and a tight finish size can make hitting spot-on difficult.

OKAMOTO ACC-618DX3 FULLY AUTOMATIC SURFACE GRINDER | Naab Machinery

Probe stop SGs just keep grinding until you actually make size, but they are fancy and expensive.
Home - MachMotion

I have an Acer 12x24 grinder I want to sale. I got it 6 months ago for a job that didn't come through. I want $5000.00 for it. The grinder operates good as far as the feeds and spindle and all, but I haven't ground any parts on it to know how accurate it is. I can get pics if you have any interest. Thanks Jason

michiganbuck said:

Here is a kent programable SG but it is in California(Oxnard). (kent is a decent machine.)
2010 KENT USA Rotary Table Surface Grinder Programmable KGS 1020SD 10" x 20" | eBay

But the photo does not show a rotary table machine???
2.25" od by x.xxx"
Some/most programmable stop SGs give a take-off amount, so you start at perhaps + .010 going to zero(if you deem that +.10 the high part and grind a little air, then grind parts to size by taking off a specific amount. But having a high variance in rough size and a tight finish size can make hitting spot-on difficult.

OKAMOTO ACC-618DX3 FULLY AUTOMATIC SURFACE GRINDER | Naab Machinery

Probe stop SGs just keep grinding until you actually make size, but they are fancy and expensive.
Home - MachMotion

Click to expand...

That Kent machine is nice looking. I never saw it in my myriad of eBay searches actually. I messaged on it.

demoj21 said:

I have an Acer 12x24 grinder I want to sale. I got it 6 months ago for a job that didn't come through. I want $5000.00 for it. The grinder operates good as far as the feeds and spindle and all, but I haven't ground any parts on it to know how accurate it is. I can get pics if you have any interest. Thanks Jason

Click to expand...

Please do! Shoot me a PM.

super you might get better advice with positing the part dimensions

Part is 2.25" od by x.xxx" with a maximum of .xxx" to take from two sides and finish size tolerance of +-.xxx"
Squareness from rough is good enough. or must be qualified to .xxx, and a surface finish of xx.

Acer 12x24 grinder... A decent Acer is a good machine.

Manually running a row of parts you might place two spotters at each (or one) end of the row.
The spotter is grease penciled marked and has a tap of masking tape on its top.
With .010 on the part you hog grind off .008 or so and then become more careful with watching your spotter.
Taking the masking tape you know that you still have .002 to go to part size.

Your finished parts can also be the spotters.

Now you do one or both of two things.
#1. carefully watch to see a wiping of the grease pencil marking, knowing that when it smears you are at your high part size and when it is almost gone you are spot on size.
#2. you take the wheel over to your pre-set height dresser and skim (spot on) dress the wheel. with knowing that dial .001 past the dress number is your spot on part size. Yes, you look at the down dial at dressing and then go +.001 more dial on the part, size might be .00025 past or right on the dress dial number. Once you know you might run/grind all day with not measuring a part.

One trick to fast grinding is to let your machine become the measuring device. Most decent surface grinders can finish to .001 (and even .0002) with no taking the part off the chuck for measuring.

Having enough horsepower you might full-wheel the part by choosing an open, harder wheel and incrementing down with only long travel on the part to +.001 (or what is needed). Then spot dress, cool the part and cross pass the part for size and surface finish.
Down grinding will wear the wheel only where that wheel is on the part so this wheel condition must be considered. With grinding experience, a grinder hand may off-the-part to the close and far with each row to keep the wheel flat, or choose the needed frequencies dressings.

Having a large enough chuck you might fill the chuck with a number of rows.
*Continual setting parts on the bump rail will wear out that area of your chuck and so need more frequent chuck grinding, placing parts all about your chuck will save that need. Having some flat parallels can divide your chuck into 4 different sections so each month you move to the next section (perhaps 1/4 x 2 1/2" CRS would be OK).

"Spot on dress" is dressing to a pre-determined size/height.

Yes I will save this for my book.

oh, and the wheel..
In order to remember grinder wheel hardness one might think of this

B to T grinding wheels hardness. what letter is going harder?
*Wheels are Butter to Tungsten.

A soft wheel has a bond(holding grits) that lets lose easier.

a nice machine..if in good condition(?)
Jung Profiltechnik Surface Grinder | eBay
Another JUNG but having no manual handwheels
Jung JA600 CNC C Grinding machine | eBay

No, I am not tooting Jung. likely it is a good/great machine. I have only had hands-on once.

michiganbuck said:

a nice machine..if in good condition(?)
Jung Profiltechnik Surface Grinder | eBay
Another JUNG but having no manual handwheels
Jung JA600 CNC C Grinding machine | eBay

No, I am not tooting Jung. likely it is a good/great machine. I have only had hands-on once.

Click to expand...

Thanks for all the help! A 618 Micromaster with auto downfeed actually popped up close to me. The ones with auto downfeed seem kinda like unicorns, so I jumped on it right away for $2k.

A 618 Micromaster Is a world-class machine...Meaning very, very good.