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Essential grinding tooling

Inspect your spindexes for parallel to base, square to front, and camming.
(simple checks) If they are good, or if the unit is good enough to be worth fettling so they are (qualtiy of these units varies quite a bit) it can easily be more than adequate for most spinning and simple angle stuff. Where Mastergrinds et al shine, is the ability to move parts off center, precisely, with the rack and pinion sliding Vee block. & setting stops for the various motions.

I have a Suburban mastergrind and use it from time to time,
But for making punches for the rotary broaches, and for simple spinning, i save it in its case in my office, and use a cheap import spindex that i qualified decades ago.

Grab a 16th's or 32nd's set of 5 ST collets when you see one - the extra engagement length allows accurate grip on the body of a drill or tap, or other round tool, for shaping/sharpening the lips.

Never turn down the opportunity to pick up cheap magnetic transfer blocks. Keep a good set(s). But orphans and oddballs have a lot of use, remilled/ground into angles, small pot-type chucks, ledge or groove, etc, etc. I sometimes leave a ledge when making an angle, so the part can't slide downhill.

If you plan to make cutting tools or regrind odd balls, keep an eye out for an All-Tool rotadex. They aren't cheap anymore, so don't rush into it. But keep an eye on auctions especially local machine shop auctions where there is not a big audience paying attention. Maybe one will come your way in a few years by the time you actually need it. :) Be sure it has the over-arm ("under arm"?) and a good crank/draw bar. There are a lot out there beat to death with missing parts and a huge price tag. This one shows what should come with one.


All-tool-rotadex-5C-compound-grinding-fixture-nice-picture-3.jpg


Also for small tool making, keep an eye out for a PC 101 and be sure it comes with all the parts, in good condition, too. They were designed for sharpening taps, but work well for making wing type cutters with cam relief.

BMCPC101SharpeningFixturePolyChokeE.jpg


Your idea of a single angle mag sine chuck is good, too.
The double angles are wonderful when needed, but that is rare. And by the time everything is set up, there's about 1/2" of daylight left under the wheel with it all the way up! (Exageration, but it happens)

Radius and angle dresser. There are some simple ops, that just are easier with the angle dressed in the wheel. I was reminded of that recently, making a couple step drills.

Good luck!
smt
 
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The very basic is an angle plate with a couple of clamps, a V block with a clamp(one that can be set on its side is good), a pair of 123 blocks, a bar diamond dresser, measuring devices perhaps a 1 2 and 3 " micrometer, and perhaps a digital caliper to .ooo5, a small surface plate, A device to check squareness like a V nose surface gauge. A simple height gauge with an indicator, a bump rail for the chuck, a right-angle triangle to right-angle off the bump rail, and some block in blocks.
 
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Grind a size to .0002, , Grind a rectangle to .0002 squareness. grind a step and step distance to an edge to .ooo5, grind a nice looking edge bevel to all sides of a part (perhaps .015 x 45*, try down grinding and incremental cross grinding. practice some kind of coolant use, grind a second part by using another part for a spotter with not losing any size from the first part.

Parting wheels can be tricky to n=ot break the at installing to a mount, but once you get the hang of using them they can save a lot of grinding time.
 
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I need to make a squareness gauge for the surface plate and should be set for a lot of things. Still waiting on backordered Bijur metering valves for the machine.

I used my tool grinder to make a d-bit reamer for a taper pin, by indicating from a base sliding on top of a sine bar to the top of a pin held in the univise. It was a cumbersome approach but worked just fine. A mag sine plate and a fixed spin device would have been easier.

I’d appreciate more detail how to qualify a spindexer’s squareness. Should I reference a collet-held pin or the indexer bore?

Once I have a squareness gauge I can determine my angle blocks’ accuracy.
 
I’d appreciate more detail how to qualify a spindexer’s squareness. Should I reference a collet-held pin or the indexer bore?

Once I have a squareness gauge I can determine my angle blocks’ accuracy.

The way I did mine was to put a straight, round bar in the spindexer with a good quality collet (I used a Hardinge) then indicate the pin/bar at both ends (near collet and some ways out) while spinning the spindexer to make sure it's running true. From there set to the pin with an indicator for milling and/or grinding the base.
 
Here is a V nose surface gauge, you just put a ball in the V and then roll an indicator to your part to check squareness. A rough square check is to just bump your 123 block to the part.

Like ekretz said an indicator striking a held pin is great, sometimes the last .oo1 or .oo2 can be better adjusted with a slip of copy paper set under the spin index. a block-in block touching the go side is good practice with any set-up.

Sometimes one can true the radial error by turning the collet a quarter or half turn.

In making cutting tools it can be good to spin circle grind and then add clearances.

Being able to dress and then grind an angle is very handy in making cutters..
 
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An option for pins, are dowel pins. (cheap)
They are very uniform in size, meaning you can use 2 or 3 out of the same box, for some gaging and spacing purposes. (where you are locating things. I would not use a dowel pin for specific size reference, generally

Small dowels are cheap by the box, but my jobber will sell singles in the larger sizes. They are still cheap. I have some long ones in 1/2", 5/8" & 3/4".

It's worth checking the larger dowels, but they are generally very straight and round for run of the mill use. It is possible to get some occasionally that have lobing errors, but i think that is rare these days.

I do what eKretz described, and Buck expanded on.
Use your best collet, but also rotate and dial out the error, comparing at somewhat distant points. Mark the high spot close to the collet, then out 3" away. if the error is in the collet or pin, turning to split the difference between the high spots will be very close.

If things look suggestive of cutting metal/grinding on the spindex, then best first to indicate the spindle inside and out, to be sure the collet seat & bore for the draw tube are concentric with the OD. Indicating the taper directly can be tricky, because these generally cam a little bit axially. If prelim checks suggest the spindle is ok, then sort of the first actual attack could be fixing the camming. I have to be honest and say "I always meant to get around to that" :) But in fact it does not matter for most spinning, and even for punches like hexes and squares for rotary broaching. Unless you have to hold a square shoulder on something or spin grind a true flat face. Usually that is when the Master grind comes out. Otherwise the spinner would get fixed.

smt
 
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A paint brush with a wooden handle. Use the handle to knock loose grit from a reach wheel. It helps improve surface finish.

Also a Optidresser if it fits on you machine. Dead handy for dressing radii and angles and a combination of both on the wheel profile.
 
Impossible task: grinding angular serrations on a 14 " diameter knurling wheel.
Going across the part at an angle requires rolling the part on a big radius as you cross the part with a wheel.
I never tried it on a CNC but on a manual grinder failed to get it right.
 
Those Grind-All fixtures have been sold under various names. Mine is an Atco Punch-Mate #1. Wouldn't trade it for the world as I use it constantly. Something else to consider is fabricating a vacuum chuck- I need to do this. I'm constantly getting stuck grinding thin non-magnetic stuff and double stick tape isn't all it's cracked up to be- you'll often bend the part removing it, plus you need to flip it a lot to avoid warpage. A sine bar is near to useless, but a sine plate with mounting holes is quite useful- https://www.shars.com/products/workholding/sine-plates
 
I need to make a squareness gauge for the surface plate and should be set for a lot of things

Once I have a squareness gauge I can determine my angle blocks’ accuracy.

The V nose surface gauge and a ball bearing is good. I modified a surface gauge about 30 years ago using a short piece of 1/8" CRS set into a slot ground into the surface gauge. It's served me well over the years. A similar one is found in the link below.
 
Don't forget a couple parallel clamps to clamp your work to the angle plate. C-clamps can cause the work to twist whereas parallel clamps squeeze without twisting.

Roger
When squaring blocks; grind top and bottom of all the largest surfaces first. Then lay your six-inch scale on the chuck. Turn your angle plate upside down on the six-inch scale and turn on the magnet. Lay your work next to the angle plate "on the chuck" and clamp it to the angle plate with two parallel clamps and grind one side of the next largest surfaces. Raise the grinding wheel one turn and continue to grind until all the blocks are complete. This will help you become efficient without working you to death. Turn your angle plate on its side on the chuck. Clamp with two clamps and grind the ends of your block. Be sure to block any blocks standing on end.
All the Best
Roger
 
I think it is a good idea to inspect your 123 blocks to find a long-way that checks to under .0002 to square and gun blue those to sides so as to be the checking fixture and to check your checking method.. Many chucks get low at center chuck on the bump rail. It is really a bugger to grind 2 tenths or 20 millionths with an error chuck

Someone (rogertoolmaker)
said 2 clamps.. which is a must-do with grinding.

One cant beat a simple v nose surface gauge for checking square.
 
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