Surface Grinder Ripples

[CarbideBob]

I'm a little confused about the terms being used - "long travel" is side to side, as in reciprocating, yes? And cross feed is in (or out), for the stepovers?

In the surface grind world X/Y/Z.
Standing in front intuitively Z is up/down.
By standard machine definition Z is the in/out.
So we say long or table travel and cross feed.
On my cnc SGs I put Z up/down since it easier to grasp. This is all so wrong.

Down grinding is sometimes call plunge grinding.
Also related to creep feed grinding where you take a lot in one pass at slow table speed.
We will take .250 or more deep in carbide in one swipe on the grinders.
Think making a drill or endmill flute from solid, no way you have time for lots of passes.

 

[eKretz]

I'm a little confused about the terms being used - "long travel" is side to side, as in reciprocating, yes? And cross feed is in (or out), for the stepovers?

Yeah, Buck is just using "long" for longitudinal - or side to side as you face the end of the spindle. Cross for crossfeed - or in and out, toward or away from the end of the spindle. So yup, you've got it, you're not confused at all.

And to add to Bob's comment, plunge grinding is also sometimes called "slot" grinding.

 

[michiganbuck]

There are a number of surface grinder manufacturers around the world that have XYZ different, with Z and Y opposite... so I call the three travels on a non-CNC grinder Long Travel, Cross and Down.
I have the odd companies listed somewhere in my notes.
For everybody to agree to one XYZ would be good.
I used to run and write programs for a CNC grinder with WXYZA&B...It could do almost anything..even catch on fire.

 

[michiganbuck]

We are getting off-topic but to justify my coining the term Down Grinding, we need a word to describe that kind of grinding. Incremental cross-feed grinding is feeding across with the cross-feed in increments to take stock. Down grinding is incremental feeding with the down feed to take stock.
If one wanted to make a crew sheet* for a particular job/part and that kind of grinding had proved best then a descriptive word for that kind of grinding would be needed.

RE: *Crew sheet: a written description for a job/part procedure made so a/each person does not need to re-engineer the work process for the part.

* We need Juston to finish his part and post a photo of it with a near-perfect surface finish.

 

[michiganbuck]

OT: A small portion of my not yet completed/published book
:
My words related to surface grinding:

-The part: The workpiece to be ground.

-Parked; Not moving, most often referring to the wheel.

-Down side: Most often the part side set on the chuck or on a surface plate.

-Wheel loading and dulling: The wheel becoming loaded with stuck material fused to the abrasive grits, and dulling when abrasive grits becoming less sharp.

-Dressing: Reconditioning any area of the wheel, most often the bottom or OD.

-Intermittent cross feed grinding: Grinding with a set down feed and then crossing over the part with incremental step-overs using the cross feed.

-Down Grinding: Grinding with the wheel stationed over the part and using incremental down feed travel along with long travel movements to grind the part.

-The grind side: The wheel traveling onto the part with the grinding action and wheel rotation pushing the part away from the direction of the feed.

-The climb side: The wheel traveling onto the part in a manner that the grinding action and wheel rotation pulls the part onto the feed direction,

-Feed side: The side of the wheel where the direction or force of feed is exerted on the part, for example the direction of cross feed on a part.

-The Go direction : Where the part would go if free from all holding.

-Block-ins: noun: A thing placed on the chuck that blocks the part from traveling in a direction due to wheel or feed pressure on the part.

-Block-in Verb: The action of placing a thing that stops the part from moving.

Yes, in the text explanation is given such as "The climb side" may have specific problems that need further description that is given in Grinding Technics.,

 

[richard newman]

Thanks for helping us all understand the lingo and techniques. Of all the operations I've done, grinding remains the most mysterious to me, seems as much an art as a science.

 

[michiganbuck]

Thanks for helping us all understand the lingo and techniques. Of all the operations I've done, grinding remains the most mysterious to me, seems as much an art as a science.

Descriptive words are important.
For example: "The Go direction"...
The primary Go Direction would be flying off the chuck the way the wheel rotation would throw it to go flying across the shop, and a secondary Go Direction might be the direction of the cross-feed stepover because the wheel's far edge pushes in that direction, and may increase if the wheel is too hard and loading occurs. (the Ops part in photo #1 is an example of problem causers being *burning, *snagging, *stalling and *skipping ... other special words..
Another potential Go Direction is the part sliding on the magnetic chuck because
*hog-grinding is exerting more pushing than the holding ability of the chuck, another is a part tilting because of having only one clamp when held to an angle plate, and another is the part it toppling over because it is too tall to stand with a small area on the chuck with not being blocked in or clamped to a solid structure, another would be downward if the part was thin and warped to a hollow under the part allowing wheel pressure to push is down at its midsection.

All/Many of these things need descriptive words so when teaching an apprentice talents are not easily forgotten..so he/she might know the factors, not just that one set-up.

 

[DrHook]

I recently acquired a Brown and Sharpe No2 from 1941 which shows no sign of coolant ever being used on it. (no rusting or fluid "flow stains" anywhere) Was oil based coolant used "back in the day", or did it likely just get used for light duty work where coolant wasn't a necessity? I haven't disassembled it yet,(or run it) but everything operates very smoothly.

 

[4GSR]

I run mine dry. I do have flood coolant setup but just never use it on mine. The main reason for not using it is, I don't use it enough deal with the coolant mess when it goes sour.

 

[eKretz]

I recently acquired a Brown and Sharpe No2 from 1941 which shows no sign of coolant ever being used on it. (no rusting or fluid "flow stains" anywhere) Was oil based coolant used "back in the day", or did it likely just get used for light duty work where coolant wasn't a necessity? I haven't disassembled it yet,(or run it) but everything operates very smoothly.

Either is possible. There absolutely was water soluble oil coolant, but it could certainly still leave stains. Looked like milk. If it was changed regularly enough staining was less likely.

 

[michiganbuck]

I run mine dry. I do have flood coolant setup but just never use it on mine. The main reason for not using it is, I don't use it enough deal with the coolant mess when it goes sour.

It is not uncommon to run dry. I know of a major manufacturer of special cutting tools who would not allow any coolant use on a surface grinder. that takes a little time and caution.

Some grinders had a special/unique spindle end cap for wet grinder/coolant use.
Grinding carbide wet is best for surface finish, edge, and wheel life. IMHO.
My #2 B&S SG is likely that old and still a very good machine. It has a homemade spindle replacing the plane-bearing spindle (That way when I bought it). I think a plane-bearing spindle gives a better surface finish but takes a few minutes to warm up.

 

[richard newman]

I'm glad to hear running dry is ok. I have a simple Boyar Schultz 612, and in a woodworking shop I'm very reluctant to use coolant, could be a major problem if it got on the wood. I use it only occasionally, mostly on high speed and carbon steels. Never in a hurry, or have a huge amount of parts.

 

[Zap921]

Good thread for sure. I'm still waiting to hear more from OP after all this input and guidance. On another note, actually took the time last night to try some suggestions from this thread. My Reid Hydraulic definitely does grind a better finish when cross-feeding front to back. Also took a look at a couple of finishes with different speeds when dressing the wheel, again another eye opener. Thank you guys that do this for a living and help us home wannabies out. Much appreciated!!

 

[michiganbuck]

If you don't have an air system you can remove the stop barrier at the left end of the table, add a sheet metal box with an angle down deflector leading into a 20-gallon open barrel and almost all your dust grits will go into that barrel/bucket...Washing soda and wither makes a decent anti-rust coolant that is safe to dump....but if touching near very hot steel it can go solid and need wiping off the part.

We are getting way off the Op's topic..

Surface Grinder Ripples​

I'm sorry Justin...still waiting for follow-up on your part with a perfect finish
Buck

 

[CarbideBob]

Also took a look at a couple of finishes with different speeds when dressing the wheel, again another eye opener.

This is the 800 pound gorilla in the room.
From slow to what seems way, way too fast.
In deep and fast like trying to put threads in the wheel surface one way.
Lessons here.

 

[eKretz]

Yes, dressing speed is very important. While all of you less experienced fellas are reading this thread and thinking about wheel dressing, if you haven't already got this, you might want to download a copy:

Norton's "For Grinder Hands Only" Wheel Dressing Manual

I was looking through some of the hanging folders of papers, reference materials and various other things I've collected throughout my days working in the machining trade and ran across this little 20'ish page booklet. I remember getting it a very long time ago but had forgotten I'd even had it...

www.practicalmachinist.com

 

[michiganbuck]

I used to tell an apprentice to dress at a comfortable speed @.001 and .002.
Steve Barton of solid rock posted sticking the freshly dressed wheel with a piece of wood to dislodge the loose grits, he said to use a popsicle stick ...and somebody posted charging a wheel with rouge and beeswax ( I have not tried that, but I used to mark up a part with the old grease pencil. I haven't seen the old grease pencils lately and now people are using a china marker for a grease pence that is hard grease and doesn't help finish..
Also told them that some grinders have a sweet cross direction that gives a better dress and finish..and for some grinders, direction doesn't matter.
I think that a big step over is bad for the finish and a small step over ,02 - ,o50 often will give the best finish.
Way back before, my time guys would re-braze a diamond to a sharp facet..

 

[eKretz]

I occasionally clear vitrified wheels of loose grit with a block of scrap steel. Wood would probably work okay too. Of course I never advise anyone to try this, but the loose grit particles sticking out of a freshly dressed wheel can actually be felt if you very lightly touch a finger pad to the wheel OD immediately after dressing. They stick out past the dressed surface and are only hanging on loosely. They can cause finish issues sometimes, but if you'll be taking more than a couple thousandths off the work after dressing they'll usually pop out on their own.

To the lesser experienced: Observe precautions if touching anything to the wheel, only approach from the right side of the wheel as it's spinning clockwise and be sure there's plenty of clearance under the wheel - DO NOT place your fingers or anything else anywhere near what could become a pinch point. A fresh dressed grinding wheel is VERY capable of removing a finger in such a situation. Very gentle touch on the bottom of the wheel with the left top side of the item only while holding from the right side of the item being touched to the wheel. No danger of jam up that way. Good idea to make the item of decent length to keep well clear of the wheel.

 

[michiganbuck]

Good thread for sure. I'm still waiting to hear more from OP after all this input and guidance. On another note, actually took the time last night to try some suggestions from this thread. My Reid Hydraulic definitely does grind a better finish when cross-feeding front to back. Also took a look at a couple of finishes with different speeds when dressing the wheel, again another eye opener. Thank you guys that do this for a living and help us home wannabies out. Much appreciated!!

Thanks Zap, good to have someone confirm that happens on some surface grinders.

 

[michiganbuck]

QT: Justin...the Op.
(I am new to surface grinding and have been experimenting with our Proth surface grinder on a test piece of steel.)

Justin, don't abandon this thread. Everybody is waiting for a photo of the final grind on your part. You might strive to become your shop's grinder hand. that is a great position, and once you know the ropes an easy but highly respected position.
Buck

Ps : If that is your piece of steel you might grind it perfectly flat and perfectly square on the ends so it might become a special fixture/gauge/parallel for your toolbox. shoot for .0002 or so. You might box it in with 123 blocks to get the narrow sides, grinding the ends might be tricky so double clamp to a solid structure/fixture and be very careful.