Old surface grinder; worth buying?

Last weekend I went to have a look on an old surface grinder (Erma). I don't really need one, but sometimes one would be nice to have (planer and shear blades, knives, odd parallels etc.). The small ones are really rare here in Finland. This is the first one I've seen while looking for them during this autumn.

The obvious fault with the machine is that there is no magnetic chuck. However, the price for the machine is not that high (250€=$290). A suitable magnetic chuck costs about the same.

I did some tests with a dial indicator. There is no runout in the spindle. The table seems to move as it should. There was 0.02 mm z-direction difference from left to right. It was more or less linear.

It didn't have a diamond dresser (or anything else with it) so I wasn't able to true the stone. However, I did a small test with a piece of steel attached to a drill press vice. There was obviously a little bit of chatter. I don't have a reference surface, but using my parallels and looking in front of a light it seemed to be quite flat. More or less comparable to having two parallels together. The stone was attached to the spindle using plastic bushings.

The biggest worry I have is that the ways seem to be quite worn on both ends. Middle part is in good condition. When the table is in the middle there is no up and down movement, but when moved to either extreme I can make it rock a little (~0.04 mm).

I've never worked with a surface grinder before, so I need bit of help in deciding whether to buy this or not.

Certainly your needs determine what to buy. It Is an oil way machine so a bit of scraping could make it near new.
Spindle should run smooth with a fresh wheel or need new bearings..Old wheels are often out of balance if left in the same position..even with a fresh dress.
Would make a nice cut off machine or a drill sharpener with adding simple bought or home made fixtures and a true surface grinder with a little scraping..
QT:[but when moved to either extreme I can make it rock a little.} .0015 or so rock total so some scraping may be needed...but it is a quality machine so worth the scraping...Don't knoe what grinder cost their so don't know if that is a good deal.

Check the down feed nut with setting wheel on a block of wood ans see the free spin over half turn and you should make a new lead screw nut..is the cross feed hand wheel graduated.. and the down wheel graduated.If an oil spindle does it have oil?

Think it has been setting for a time so a lower offer might be tried..
A very simple long V block mounted to an angle plate makes a good drill sharpener.

Surface grinders here seem to be common and unwanted. If you're willing to put in the time and effort of cleaning it up and maybe doing a bit of scraping, it could be a nice thing to have. My old Boyar was extremely ugly, but works well (after much tune-up) and though I thought I wouldn't use it much, it's become an essential part of the shop. It seems to get used every time I go out there, and has paid for itself several times over in less than a year. Not a hard trick when it only cost a few hundred dollars to fix up.

I would find a decent magnet before buying it. Or look for a grinder that has a magnet. A new magnet can easily cost you 5x what the whole machine is worth.

Larry Dickman said:

I would find a decent magnet before buying it. Or look for a grinder that has a magnet. A new magnet can easily cost you 5x what the whole machine is worth.

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At least know where and how much for a magnet. why did the magnet come off..another reason to think a lower bid might be made.

Here around Detroit a clunker but OK SG with a magnet perhaps 200 to 350 and even free with you removing it.
500 to 2500 for a fair to good older machine.

Yes Magnets alone often go for 200 and up.

The cross feed wheel is graduated, didn't pay attention on the down feed wheel. I need to check it the next time.

Would you have a picture/video to show how to sharpen drill bits with a surface grinder? How do you make a relief angle?

There is a flat way and V-way. If I scraped the flat part, then shouldn't I also scrape the V-way? That sounds too much work for a machine that I don't expect to use much.

Would this be a decent magnetic chuck:
SCT Rectangular Magnetic Chuck 35 x 15 mm x 48 mm Milling Machine etc Grinding | eBay

chuck looks ok but you need 13.8 long travel and then a little more to grind the chuck.
6-18 grinder that would be fine.
Drill sharpening is simply to turn the fixture to the point angle and the clearance angle and straight shash acrross reach end..s for a 118* poinr at 69* turn and perhaps 10 or 12* tip up for clearance.. perhaps a long V block with ability to hole up to 1 1/4 would be fine..yes you need to hand back off the heal under the cutting edge..Don'r have a photo of such.
Yes you need to have the grinder to then buy the chuck.. chuck should have stop rail screw holes at the front of the chuck.

As someone thats had a slightly larger fully manual machine then had a hydraulic Jones and shipmen 540 i would never want to go back. Surface grinding is akin almost to shaping, lots and lots of back and forwards, powered traverse on a mill is a luxury, on a surface grinder its damn near essential. Would seriously get a bit bigger hydraulic machine and not look back. they both end up taking much the same in floor space.

Thanks for all the feedback. I guess I will keep on searching.

While you are searching - The mag base indicator on the table indicating the top of the table won't give a true picture of way wear. It can be informative if placed to indicate a good distance from where the wheel would ocntact. But even out toward the ends of the ways, it might not give a true reading over the last time the chuck was dressed.

It is like indicating on a lathe - the surface is round, but the indicator needle does not move, because in mirrors the tool position as far as the work is concerned. So the chuck ways could be quite humped, but if the table was dressed recently it will be parallel to the humped surfaces (top of chuck) and indicate -0-0- with maybe some rocking at the extremes.

You were indicating the table top, but "normal practice" for replacing a chuck is to grind the chuck pad on the table before placing it. (I grind, then scrape flat). On an old grinder, no one knows when or how well that operation was done.

smt

Still it is good iron..with plenty of scraping time it would be handy depending on your grinding needs and use of time.. if bought at the right price..perhaps just the time to move it if unwanted..

Agree with Stephen about flatness.. you could shim up a good straight edge or parallel zero /zero at the ends and the travel an indicator across that. How long do you suppose to hand scrape .002 (or what needed)?
but yes bearings and scraping would be a lot if needing that..

in the USA $500 for such would be way over priced..(machine and magnet with not the bearings if needed)

I have run manual surface grinders all day long.. it is a chore as you do what you have to..but for one-ups a manual is not that bad..IMHO. I figure you have to stand there watching so why not be moving.

Agree that machine takes up as much space as a normal 6-18 that might have better features..

Yes an operation you can program and walk away to do another task is good.

^ I DISAGREE STRONGLY!!! If grinding flat surfaces you just set the stops and leave it too it, there’s really nothing to go wrong with grinding when your use to it and have a good wheel - material combo. Compared to say a cnc mill were the cutters will go blunt and snap a grinder will just keep on grinding.

Honestly wish i had more work for it, because its so effortless and damn cheap to run compared to damn near any other tool i have.

I have run manual surface grinders all day long.. it is a chore as you do what you have to..but for one-ups a manual is not that bad..IMHO. I figure you have to stand there watching so why not be moving.

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Michigan - you are more ambitious than me. Being lazy, I put a part on, set the stops, and go hang out on PM

smt

That was my first job... Cutmore Tool Co.. Did not know any better but made good money running an old oil ways Reid with hard pulling, often running a full chuck with laying down form cutters to a marked spotter..Much +- .001 and .0005 and some close.

Nothing against auto feed and CNC..but for the Op if getting a hand machine needing scraping and a chuck.. I would offer way less than 250 if needing a surface grinder for light one ups not production work..for free it is still a lot of work if not having enough free time to practice ones hand a scraping...Yes if being able to afford a better machine he should go for that and be grinding the next day...

I'll offer a couple of comments. In another life a good chunk of my work week was spent on surface grinders, some hydraulic and most manual for die/mold components. I would usually pick the grinder per the size/shape and operation needed. For larger flat plate work just back from HT there wasn't much question, hydraulic. Load up the big wet grinders, set the stops (if equipped)and go to another task. But for a lot of the work putting in small geometry on a perforater,core pin, form punch, etc. the scale of the machine (hydraulic) just felt clumsy to work with compared to a 6x12 manual grinder. I like scaling the machine to the work required but that's just me. There were even plenty of times I had to stop the table travel in "x" that was more easily done in a manual that would be difficult with some of the older hydraulic grinders. Don't get me wrong, I liked firing up the Okamoto/Thompson/G&L when the job made that selection easy. But for quicker, smaller, or detail jobs I'll take a smaller manual over a larger automatic machine just for ease of use. Getting coolant on/in a spin-dex doesn't seem a good idea anyway. I'd dearly love to get a newer Okamoto but that's not going to happen and am hesitant to purchase an old hydraulic that's likely leaking fluid and has expensive maintenance in the future. If I had enough work to pay for that I could easily justify the added cost but for the OP and others that don't have enough occasions to run larger/production oriented work a manual is simpler,less expensive, and sometimes better suited for what the work requires. It's always about what you do in any shop and how often you need one. As for the drudgery of hand cranking on an endless sequence, I became accustomed to it and would time my fatigue to the point I needed to let the work cool anyway before final pass. Coolant systems can easily be added as well on a much more temporary basis if available work space is critical too. A small air-line spitter or drip can isn't much to rig up. There are also techniques for removing large chunks of metal (engineering change....) I do find times when my 6x12 Mitsui is lacking but the expense, footprint, and hurled coolant/particles (all over the shop) from a nice 12x24 hydraulic just cause me to find an outside shop for those occasions that warrant. Potential is nice but that has to show up now and then. A manual surface grinder should not be ruled out, tailor the machine purchases to what pays for itself. JMO

Used a little Browne & Sharpe with a lever instead of a wheel for the traverse at one time ... it was fast and easy for little parts. Didn't have to set stops or anything, just throw the part down and chunk chunk chunk chunk a few times, all done. I wouldn't discount having a very basic little grinder around, you end up using it a lot more than you'd expect.

Or maybe that stuff didn't need to be ground at all and I was just playing with myself

A 612 manual is all a home shop probably needs, but I can see where any sort of quantity production work would make one long for an automatic machine. In decent weather my old Boyer is easy as pie, but the shop is unheated. As it gets colder, that crank becomes a real muscle builder. That's one cue it's time to shut down for the winter.

It's worth having at least a 6-18 (over a 6-12) because a surface grinder is one of those machines that uses up a lot of real estate on the table fast. Put a sine chuck and a dresser on it, and you are about out of travel. Or especially, put some work on it, and a R & A dresser at one end to maintain the form, and you are about done with space.

From the commnents above, it's also pretty obvious that no one can afford to have only one.

I have an old mechanical B & S #2 6-18 that i completely rescraped a dozen years or so ago. Good for small stuff and tool work, though it now needs spindle bearings.

Selectively quoted with apologies to AD-D -

For larger flat plate work..... there wasn't much question, hydraulic. Load up the big wet grinders, set the stops (if equipped)and go to another task. I do find times when my 6x12.... is lacking but the expense, footprint, and hurled coolant/particles (all over the shop) from a nice 12x30 hydraulic.....

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Hey, I kind of resemble that remark!

surface grinder flattens planer table - YouTube

(12" Powermatic wood planer bed)

smt

I was the same way.Didn't think I really needed one but
just wanted one for the shop.I bought a Reid 618HR .I had a choice from the seller on a couple of machines.They all looked sad.Back at the shop cleaned it up,replaced the keypad covers on the Sony Magnascale dro and the oiler metering valves.Remounted the magnetic chuck and I bet ground it for the first time in it's life.Had to make a wheel guard , mist coolant system and a wheel balancing stand.Now I find that I use it more than I thought I would.No production but standing there for a few hours once in a while is not bad.

Once one gets handy with a SG it is hard to look back to fighting a mill to get close when a few minuets tickle can get you dead size or dead square...Back in the day we (I) thought a mill was for +- .001 to .005 and another few minuets on the grinder for square or close.

Yes now with ball lead screws mills are much closer than back when but fixtures, vise and table error or nicks much the same..