Nice John. A couple of things I've picked up, for what it's worth. Sometimes on the grinder it's best to think outside squares. We're so used to square in mills etc. Small objects like this will often grind better if they're set at an angle on the table, it tends to put less heat into the work and is a more gradual transition as the wheel hits the piece. I would set your travel stops further apart so the part is fully up to speed as it passes the wheel, you have them set quite tight and the table is still accelerating significantly by the looks of the video. Similarly, when doing it by hand I'd suggest a much faster traverse. Look at videos of hydraulic grinders and note their traverse speed for an idea. Again, less heat and better finish. Finally, even with a fine pole chuck, I think it's still good practice to block in little piddy pieces like this, just to be safe. I had to chuckle when you commenced the video with the statement "it shouldn't be too hard". Making an accurate gauge block that wrings correctly is really REALLY difficult, so again I admire your go for it attitude. It may not be a gauge block in the true definition of one, but you've filled the hole in your set that should do the job for most purposes. Thanks for sharing!
Even cheap gauge blocks have some precision. Before separating the stock (bandsaw) I would have lapped the top surface flat so that the magnet chuck would not pull the block out of shape. The bandsaw might relieve some stresses, but you could evaluate that with a sharpie and surface plate. After grinding to 0.002" or so over size, it also should be hardened before a final lapping to dimension. A length standard with 0.0001" specified precision should be evaluated at a few tens of millionths... a tenths indicator is not really sufficient. Keep in mind that the errors accumulate as you stack the blocks. Your thousandths blocks should be flat, parallel, and dimensioned within 2 tenths.
If you not take care to have the right temperature, you will not get a good Johansson Gage Block. Just try to ring them together, and pull them part. A real new Johansson original Gauge Block could be ringed together and hold a pull of 120 kg. They can measure change because of the heat from your hand. But yes, you did a good job with what you got.
At a company I was working for, we have just put the compressor into its own room, applied noise damping material and put the exauste and intake outside. That really helped with the noise and in addition the compressor stayed cool, because it wasn't intaking air from the the inside anymore. And the compressor was, so far I remember about 30kW.
I often wondered why you don't see machinists making their own precision tools very often. I guess, like many things it comes down to the cost of buying vs. the time cost of doing it yourself. I'm glad you decided to make your own .107 block. Very interesting video. Thanks! -mike
Good job! Do not forget to demagnitize workpiece after you are done - if not, it picks shavings badly. Also, ultimate test for flatness and surface finish is stick test - two blocks wiped with fingers should stick together if pressed and slided a little. Your gauge blocks should do it.
the issue is running flood coolant . Stopping the wheel wet will allow the coolant to run and settle in the low side of the wheel throwing the balance. out. Allow the moister to spin out and all will be ok
Just going to post this up here for folks interested in metrology in general and gage blocks in particular: emtoolbox.nist.gov/Publications/NISTMonograph180.pdf The Gauge Block Handbook is a freely available (digitally) publication of NIST (National Institute of Standards and Technology) and will greatly broaden one's understanding of true precision gages and their use.
Gauge blocks need a lot better surface finish than that one has. Grinding something flat is easier than keeping both sides flat & parallel while you lap them to a finish that will wring together with other gauge blocks,
Fantastic video - thank you! Would you mind to enlighten me as to whether using a micrometer instead of the GB / indicator setup would have yielded more accurate measurements? Or less?
Hi John Great video and just show if you think about it there is a way you can DIY, thanks for showing us In relation to the air compresser mine is only a small one but noisey non the less on speaking with a man at the local engineering company about this he has advised to place the compresser outsside with a suitable a weather proofing cover around locate the tank inside and provide a air feed from within the shop to reduce moisture and eliminated changes in air quality etc, When the weather picks up I will be giving this a go. Regards Mark Over the pond in the UK
you can't turn off the wheel after you dress the well, reason being is a very simple one: the wheel is running true when it's spinning and as soon as you turn the spindle off the wheel settles into a resting position which makes it untrue to the magnet vice. Spark out allows the wheel to clean up what's left. which means of there's any high spots the spark out gets rid of it. and it makes a better finish. you should also have your part on an angle when you're grinding. you'll have less travel per pass, that actually makes your surface finish and sizing excellent
If it were me I'd avoid pulling outside air for the compressor. Its always a lot more variable, morning fog, evening dew, rain snow etc. All result in more water in the tank and to have to remove for painting etc. Plus mid-day heat makes air less dense lowering efficiency. Inside air might not perfectly conditioned but it is significantly better than the variability of outside air. if there is a power source on the other side of the shop see if you can hide it over there and supplement with a reservoir on this end of the shop. Maybe plumb into the office/tool room for sound reduction if moving the compressor is not an option. Otherwise consider a lower end or used rotary, especially if you plan to do a lot of blasting or see your future air demands increasing.
Hi John! First of all, thanks a lot for putting up some awesome cnc content, I'm a big fan! I found this video very interesting and I was wondering if you were to do other videos on measuring accurately, I think it would be a great addition to your channel. Thanks again and keep up the good work!
If they don't wring.... probably still not precise enough to be "true" gauge blocks. btw, even "T" grade gauge blocks should fall within 6 microinch, and a flatness of 1 micro
after spending a great deal of time grinding "endseals" on a cnc surface grinder that had to be with in .0005 I found out right off the start you have to be careful even running a coolant system. The heat you put into you part will tend to bow up in the middle. This causes two problems one the obvious concave shape you get as the part moves up off the magnetic chuck. Second the part will want to shift and move if you taking heavy cuts as you are loosing surface contact with the magnetic chuck.
Hi John, Not bad at all, with minimal means to quality control. The accepted norm for testing in reference control is: Your measuring equipment has to be at least 10 times more precise than what you try to measure or achieve. In your case it's going to serve the purpose. A little safety advise when you grind very small parts, just install a larger plate of steel a little lower to the one you grind, so it's not flying under a heavy cut... (I know you have a fine pole chuck but....) Nicely done though.. Pierre
pierre beaudry Pierre is right on, the true measure of suface finish on gauge blocks is if they will "ring" together. They should stick like glue. Thanks for sharing, great video on making the part.
I would second the other comments about lapping. The most difficult part is keeping a flat surface for a part this size while lapping. Use ticky-tac or a similar compound to mold a good grip on the top of the gauge block, that way you can apply an even pressure. Also, when you are using a surface grinder and you have an interrupted cut on a precision part (here, on either end) you will want to lock the head (z axis). This slight change can roll off either end and your gauge block might not wring right. This is also especially important when grinding/resurfacing punch dies (that sharp edge being rolled will reduce the life of the part before the next resurfacing).
+Jason Rucks Also! I think the opinions about turning the wheel off before getting your hands near it is ridiculous. It's probably a result of safety protocol at job shops to reduce workers comp claims. You use bench grinders, right? This isn't much different. In addition to that, you really should dust the chuck when you're making something this precise. Even a very slight error in the chuck can manifest itself in your part, and it could be up to half a tenth bigger on one side. And, when you put your part on, ALWAYS (if the part dimensions allow, of course) SLIDE the part on from the edge after stoning the chuck and your part and wiping it clean.
+Jason Rucks And if you haven't, don't forget to balance the wheel. I just started teaching myself how to use the surface and cylindrical grinders at work, and I guarantee you will not get the most out of your machine if you do not balance the wheel first.
+NYC CNC No problem! This is all new to me too. I'm working part-time in a shop that used to have over 55 machinists, welders, and fabricators - now it has 4 because of offshoring of manufacturing. The upside is that I get to repair, play with, and teach myself to use all these great machines. It's good learning because there's no master machinists left in the shop to teach me! Slide the part on because there may be grit or dust on the chuck or workpiece. It'll get pushed/scraped off and not sandwiched between the two.
What was that dial indicator you had on the grinder ? Was it a tenth of a thousand. Can you change the backing plate of this indicator if required? - for final checking only of course...
Been wanting to get a superfly cutter for some time now. How well does it do with aluminum? I deal mostly with aluminum (6061-T6), and the face mill I'm using just isn't cutting it (no pun intended).
Make 10 and stack and measure then you'll have an average: it's a touch more accurate. Sparking out is pretty critical when grinding really counts. Othertimes no not so much, you do what you think makes sense. I would spark out a gage block. Lots of cool stuff in this video!
NYC CNC I don't wanna hurt feelings here. Sparking out won't matter on a Tormach(or most of what I see on youtube). When you can consistently measure a tenth(which is a joke among toolmakers) sparking out will make a difference. In a plant like GM or Alcoa or Deere tenths can be measured and removed. The small shop working for these companies know their limits; some can get very accurate work out- within a tenth. Sparking out is a given with grinding equipment. Those grinders are worth as much as your whole shop. It's an unfair comparison. Spring in thin parts is a B. Good luck with that! This is all way above my experience and pay-grade FYI. I have a heck-of-a-dad. Sometimes tho what he says and what younger guys are doing doesn't match up. Old toolmakers wrote the book, but they didn't finish it. You are a great innovator, picking up where they left off. Tormach is very exciting and I enjoy learning from some of your toolpaths that you setup. You've also made a believer out of me as far as Tormach goes. When I retire I hope to find some nicely used Tormach equipment... in 30 years that is.
NYC CNC One more thing. When folks on YT are running a BP and talking about removing a thou they are talking out their asses. A thou on a BP is almost impossible. You simply cannot get enough tool pressure to cut that and remain accurate on a BP. That I do know from experience. You gotta be able to measure what it is you are machining. And machine rigidity for Pete's sake! Most folks miss that part and trust the dials to do the measuring for them. I'll go back to my hole now for the day; back where I belong. Stop watching Fenner. Period. I'm not a hater, just practical is all. Guess-work is not machine-work. Working without tolerances is lazy and impractical.
That is correct. If each block is 0.0005 over it is easier to find when 10 are stacked and measured. Also a high spot shows up when they are stacked. Adjust and make a final part.
If you love grinding, you need to pickup a manual grinder. A lot more versatile than this toy (sry to say) you'll be grinding angles and radi in no time! :)
$25 is too much to spend on a real gage block with micron accuracy what is your hourly shop rate, it looks like you spent 2 hours on that project between the programming milling sawing and grinding I think you just made under $15 an hour including shop overhead or about $7.50/hr. Plus you didn't get a micron accuracy gage block just a placeholder that probably won't wring without lapping. Nice try but I don't think you made a gage block sorry....
Will that new block adhere to the others if you need to stack the blocks? Do the other blocks adhere to each other? Sorry, I know adhere isn't the right term, but was just curious on whether they have to do something special to gage blocks to get them to be able to do that.
NYC CNC When gage blocks "stick" to each other it is a phenomenon known as wringing, which is a combination of pressing the air out and a thin film of "unknown" composition. It requires an exceedingly flat and highly lapped surface. www.aspe.net/publications/Annual_2005/POSTERS/3METRO/6SURF/1831.PDF
atomkinder67 I believe that it has also been argued, though not by anyone as uneducated as myself, that wringing may induce a form of van der Waals' interaction in the surfaces via the static one imparts into the gauge block during the wiping of it across your wrist. I haven't the article to quote, but did discuss it with Tom Lipton, and he's pretty much bathed in science daily ;) Cool project, and I had wondered if you were going to lapp the block after surface grinding, and if so how you would do so in an accurate manner, or "on plane". I guess I've got my homework for tonight...Aloha, Chuck
Knolltop Farms In a lab environment gage blocks are never touched with bare hands. Very common to wear cotton gloves to partially insulate high grade blocks from the heat of one's hands.
gbowne1 As a micron is just shy of .00004" I would hope so. This depends on grade though and block length. Lab grade gage blocks one inch and under have to be within .000009" of nominal size IIRC. That's total tolerance, not +/-.
+NYC CNC I would expect you could get down to a thou or less on the Tormach with a flycutter and the appropriate feeds and speeds, and manual setting of the Z axis with indicators. It would be an interesting experiment to see what you can get out of the machine.
If yo profiled the part with the .107 in Y and cut and measured you should be able to get it within a couple of tenths just with a milled finish. I wouldn't se tool deflection being an issue over something the length of a slip. Run a spring pass, clock the tool.
Its quite a good way of marking tools actually. You can do stencils out of plastic as well then set one pole to the material, and sponge with a clamp to the other pole and dip it in vinegar then slowly rubbing through the stencil marking the part. =)
Print with a laser on overhead film (old school plastic film) and then take a excato knife to it.. in your case.. spray glue it to something, take a reeaaaaly small mill.. and well.. mill it..
NYC CNC Try this mate. 1. Use Photoshop or a similar program to create a reverse image of the numbers you want to print on the gauge block. 2. Print a black and white image of the numbers using a hi res laser printer onto a sheet of white copy paper. (Don't use photo paper.) 3. Clean the steel gauge block thoroughly with acetone or isopropyl alcohol. 4. Using a hot clothes iron, transfer the image to the gauge block. (The toner comprising the image will melt and stick to the steel of the gauge block... Well, it should.) 5. Peel the paper off the block carefully and if there are any exclusions, dab a bit of girl type fingernail paint onto the exclusions with a real small, fine brush. 6. Using another real fine brush or a bit of cotton wool twirled round the end of a tooth pick, dab ferric chloride onto the exposed steel that you need to etch. You should be able to get ferric chloride at one of your Radio Shack stores. 7. Gently wash off the etchant after five minutes or so and inspect the result. If you are not satisfied, gently apply more ferric chlorids and wait a few more minutes before washing off. Repeat as necessary. The ferric chloride should etch the exposed steel pretty well and leave a high contrast result. . Well it should. Yair... That's about it I reckon. Cheers. PS You do good stuff.
I know it might not be the appropriate place to ask this, but what kind of an education do you need to learn about machining and designing mechanical parts / machines with cnc / machining equipment?
Im also self learner, came in to metalworking 4y ago with 0% experience. Now I run 2x CNC milling machines, doing setup and programming from start to finish. Best place to learn is a machine shop ;)
Granite is harder than steel, and far, far more dimensionally stable. There are cast iron surface plates as well, but they are generally hand-scraped very, very flat, and are used commonly for lapping operations.
I am very disappointed in this video. It"s OK to make a quick and dirty replacement for a missing game block but it must be clearly understood by all that is what you are doing for the start pending arrival of the calibrated and certified article. Further, a quick and dirty gauge block must be made of good stuff you can harden to Rc 60. 4141 as quenched in oil goes to Rc 50-55. Leave off all the process control, lapping etc. You can check a 0.107 gauge block by stacking a 0.103 block on a 0.104.and stack the block you are making on 0.100. Working from a granite flat and using a gauge head and gage amplifier you can certify parallelism and size to the limits of your apparatus BUT the best you can do is make the block, determine its size to 0.0001" etch the actual size on the block, and use it only until the certified calibrated block arrives. THEN you deface and scrap the bogus block. I know this is just to see if you can make a gage block. Of course you can. Most any machinist or tool maker can, with a little care, make a close approximation of a gage block for a special purpose. In my year in the motor shop I dug up a dozen defunct ring gages and repurposed them to suit common ball bearing outer race dias. But these were plainly marked "NOT CALIBRATED! PROCESS USE ONLY. DO NOT USE FOR FINAL ACCEPTANCE!" That they were round to 15 millionths, had mirror lapped gaging surfaces, and marked for size to 50 millionths meant nothing to the QA people. They weren't in the cal and cert program. PERIOD. Deceptive looking home made gage blocks are anathema to any QA program. It's a bad apple whose presence raises doubt about how precision tooling certification and consequent product quality is assured within the organization using it. If discovered and denounced by a reputable third party your entire QA effort will fall in instant disrepute. Legal and financial consequences may follow. Shars gage blocks ain't bad for open shop use. I got Metric and Imperial and a set of Mitutoyo gage block attachments but I wouldn't use them to certify any work to tolerances closer than +/- 0.0003". Sorry this wound up a lecture. Make your gage block, demo your process, plainly and loudly declare it a demo/expedient, deface and trash it when you're done, and spend the money to buy a certifiable replacement 0.107 gage block. Noobs are watching. You are a recognized source of machine shop lore: you have responsibilities you may not have anticipated. Make your own gages to suit your work. But never slip a home brew duplicate where it might be mistaken for the genuine calibrated article.
So that is +\- 50 millionths of a inch and your indicator is only capable of 5 tenth thousands. So yea it really wont be a gauge block certified although with a good ground mirror finish if it wrings together your flatness is gonna be gage quality. It u will have no way to certify it.... now on the flip side u and i both know that if u are within .0002" or better yet .0001" u are more accurate than most any job will ever call for. It is just the entire Point of a gage block is to be more accurate than anything u can create aside from grinding. Also it needs to be seasoned steel heat treated to 65 Hrc so 4140 lre hard is only 30Hrc and that is not even close to hard enough. A2 tool steel hardened and tempered at the lowest temper range will yeild 60hrc so that will work and even better yet S7 tool steel will get to 65Hrc.
NYC CNC chevalier cnc surface grinders climate controlled also parts are frozen to restructure the steal so it will always return back to it size in a nut shell
Your measuring in 0.001” which is absurdly coarse for a gauge block, how about for starters using a 0.001 Millimeter gauge? These things are measured in light wavelengths and you are trying to make one with a ruler. 1 thou equals 1/200 millimeter /0.0254 millimeter while a metric “thou” equals 1/1000 of a millimeter or 0.001mm and a gauge for measuring that can be found worldwide at just about any hardware/toolstore, but apperently not in the usa. But he!? , 1 thou sounds cool and sounds quite accurate.
I don't have any experience with surface grinders, so it's refreshing to see it used in a "home shop" setting. Very helpful John, Thanks.
Nice John. A couple of things I've picked up, for what it's worth. Sometimes on the grinder it's best to think outside squares. We're so used to square in mills etc. Small objects like this will often grind better if they're set at an angle on the table, it tends to put less heat into the work and is a more gradual transition as the wheel hits the piece. I would set your travel stops further apart so the part is fully up to speed as it passes the wheel, you have them set quite tight and the table is still accelerating significantly by the looks of the video. Similarly, when doing it by hand I'd suggest a much faster traverse. Look at videos of hydraulic grinders and note their traverse speed for an idea. Again, less heat and better finish. Finally, even with a fine pole chuck, I think it's still good practice to block in little piddy pieces like this, just to be safe.
I had to chuckle when you commenced the video with the statement "it shouldn't be too hard". Making an accurate gauge block that wrings correctly is really REALLY difficult, so again I admire your go for it attitude. It may not be a gauge block in the true definition of one, but you've filled the hole in your set that should do the job for most purposes. Thanks for sharing!
Even cheap gauge blocks have some precision. Before separating the stock (bandsaw) I would have lapped the top surface flat so that the magnet chuck would not pull the block out of shape. The bandsaw might relieve some stresses, but you could evaluate that with a sharpie and surface plate. After grinding to 0.002" or so over size, it also should be hardened before a final lapping to dimension. A length standard with 0.0001" specified precision should be evaluated at a few tens of millionths... a tenths indicator is not really sufficient. Keep in mind that the errors accumulate as you stack the blocks. Your thousandths blocks should be flat, parallel, and dimensioned within 2 tenths.
Love that Starret indicator, I use that same model all the time to indicate my vises and table tram
If you not take care to have the right temperature, you will not get a good Johansson Gage Block. Just try to ring them together, and pull them part. A real new Johansson original Gauge Block could be ringed together and hold a pull of 120 kg. They can measure change because of the heat from your hand.
But yes, you did a good job with what you got.
I've recently learnt that surface grinding is only level 2 of flatness, I made some lapping plates for a friend of mine so he can do optic lapping.
At a company I was working for, we have just put the compressor into its own room, applied noise damping material and put the exauste and intake outside. That really helped with the noise and in addition the compressor stayed cool, because it wasn't intaking air from the the inside anymore. And the compressor was, so far I remember about 30kW.
I often wondered why you don't see machinists making their own precision tools very often. I guess, like many things it comes down to the cost of buying vs. the time cost of doing it yourself. I'm glad you decided to make your own .107 block. Very interesting video. Thanks!
-mike
Good job!
Do not forget to demagnitize workpiece after you are done - if not, it picks shavings badly.
Also, ultimate test for flatness and surface finish is stick test - two blocks wiped with fingers should stick together if pressed and slided a little. Your gauge blocks should do it.
You are a very generous man, thank you.
the issue is running flood coolant . Stopping the wheel wet will allow the coolant to run and settle in the low side of the wheel throwing the balance. out. Allow the moister to spin out and all will be ok
Just going to post this up here for folks interested in metrology in general and gage blocks in particular: emtoolbox.nist.gov/Publications/NISTMonograph180.pdf
The Gauge Block Handbook is a freely available (digitally) publication of NIST (National Institute of Standards and Technology) and will greatly broaden one's understanding of true precision gages and their use.
Gauge blocks need a lot better surface finish than that one has. Grinding something flat is easier than keeping both sides flat & parallel while you lap them to a finish that will wring together with other gauge blocks,
Fantastic video - thank you! Would you mind to enlighten me as to whether using a micrometer instead of the GB / indicator setup would have yielded more accurate measurements? Or less?
Hi John
Great video and just show if you think about it there is a way you can DIY, thanks for showing us
In relation to the air compresser mine is only a small one but noisey non the less on speaking with a man at the local engineering company about this he has advised to place the compresser outsside with a suitable a weather proofing cover around locate the tank inside and provide a air feed from within the shop to reduce moisture and eliminated changes in air quality etc,
When the weather picks up I will be giving this a go.
Regards Mark
Over the pond in the UK
you can't turn off the wheel after you dress the well, reason being is a very simple one: the wheel is running true when it's spinning and as soon as you turn the spindle off the wheel settles into a resting position which makes it untrue to the magnet vice. Spark out allows the wheel to clean up what's left. which means of there's any high spots the spark out gets rid of it. and it makes a better finish. you should also have your part on an angle when you're grinding. you'll have less travel per pass, that actually makes your surface finish and sizing excellent
If it were me I'd avoid pulling outside air for the compressor. Its always a lot more variable, morning fog, evening dew, rain snow etc. All result in more water in the tank and to have to remove for painting etc. Plus mid-day heat makes air less dense lowering efficiency. Inside air might not perfectly conditioned but it is significantly better than the variability of outside air. if there is a power source on the other side of the shop see if you can hide it over there and supplement with a reservoir on this end of the shop. Maybe plumb into the office/tool room for sound reduction if moving the compressor is not an option. Otherwise consider a lower end or used rotary, especially if you plan to do a lot of blasting or see your future air demands increasing.
You get so excited about this things, you crack me up. I love it!
NYC CNC
please dont, its great to see someone excited in what they are doing
cheers
Ha ha, I got it this time.
Hi John! First of all, thanks a lot for putting up some awesome cnc content, I'm a big fan!
I found this video very interesting and I was wondering if you were to do other videos on measuring accurately, I think it would be a great addition to your channel.
Thanks again and keep up the good work!
Wow I am shocked to see negative comments. Love all your videos.
If they don't wring.... probably still not precise enough to be "true" gauge blocks.
btw, even "T" grade gauge blocks should fall within 6 microinch, and a flatness of 1 micro
Being a grinder, I laughed watching you run that surface grinder. In all fairness though, I couldnt run a mill or lathe to save my life.
How awesome is that surface grinder! I’m new to watching machining videos and I think this is so cool!
Awesome job John!
Very Cool! Great job!
Dale d
Very nice stuff John. I love it. Great job. Rick
after spending a great deal of time grinding "endseals" on a cnc surface grinder that had to be with in .0005 I found out right off the start you have to be careful even running a coolant system. The heat you put into you part will tend to bow up in the middle. This causes two problems one the obvious concave shape you get as the part moves up off the magnetic chuck. Second the part will want to shift and move if you taking heavy cuts as you are loosing surface contact with the magnetic chuck.
Hi John,
Not bad at all, with minimal means to quality control. The accepted norm for testing in reference control is: Your measuring equipment has to be at least 10 times more precise than what you try to measure or achieve.
In your case it's going to serve the purpose.
A little safety advise when you grind very small parts, just install a larger plate of steel a little lower to the one you grind, so it's not flying under a heavy cut... (I know you have a fine pole chuck but....)
Nicely done though..
Pierre
Have you tried if it will "Ring" with the other blocks?
pierre beaudry
Pierre is right on, the true measure of suface finish on gauge blocks is if they will "ring" together. They should stick like glue. Thanks for sharing, great video on making the part.
Refer to your older videos where you were experimenting on polishing...
I would second the other comments about lapping. The most difficult part is keeping a flat surface for a part this size while lapping. Use ticky-tac or a similar compound to mold a good grip on the top of the gauge block, that way you can apply an even pressure. Also, when you are using a surface grinder and you have an interrupted cut on a precision part (here, on either end) you will want to lock the head (z axis). This slight change can roll off either end and your gauge block might not wring right. This is also especially important when grinding/resurfacing punch dies (that sharp edge being rolled will reduce the life of the part before the next resurfacing).
+Jason Rucks Also! I think the opinions about turning the wheel off before getting your hands near it is ridiculous. It's probably a result of safety protocol at job shops to reduce workers comp claims. You use bench grinders, right? This isn't much different. In addition to that, you really should dust the chuck when you're making something this precise. Even a very slight error in the chuck can manifest itself in your part, and it could be up to half a tenth bigger on one side. And, when you put your part on, ALWAYS (if the part dimensions allow, of course) SLIDE the part on from the edge after stoning the chuck and your part and wiping it clean.
+Jason Rucks And if you haven't, don't forget to balance the wheel. I just started teaching myself how to use the surface and cylindrical grinders at work, and I guarantee you will not get the most out of your machine if you do not balance the wheel first.
+NYC CNC No problem! This is all new to me too. I'm working part-time in a shop that used to have over 55 machinists, welders, and fabricators - now it has 4 because of offshoring of manufacturing. The upside is that I get to repair, play with, and teach myself to use all these great machines. It's good learning because there's no master machinists left in the shop to teach me! Slide the part on because there may be grit or dust on the chuck or workpiece. It'll get pushed/scraped off and not sandwiched between the two.
I'm jealous... I want to expand my shop and get some new tools like a surface grinder.
Yeah just need more business to pay for those deals. I'm getting there but I'm chomping at the bit the entire time.
Excellent procedural work on this one.
Pity for the indicator, but hey, it happens. "Whaddya gunno do"?
John, could you have used the tenth indicator you have in the surface grinder to do your comparison tests? Is it easily removable from the grinder?
NYC CNC
Not quirky. It's a good rule. It makes a lot of sense. :)
What was that dial indicator you had on the grinder ? Was it a tenth of a thousand. Can you change the backing plate of this indicator if required? - for final checking only of course...
Very nice job.
Congratulations from Brazil.
Eng. Nilton Polydoro
Been wanting to get a superfly cutter for some time now. How well does it do with aluminum? I deal mostly with aluminum (6061-T6), and the face mill I'm using just isn't cutting it (no pun intended).
you should have stamped it 107 and take a skim cut to get it flat before you cut it with the band saw, just for identification purposes..
I hate to ask but would it have been practical to engrave the .107 into the surface before final grinding to thickness ?
Would it be better to leave a thou on the block and then lapping half a thou off each side?
Thats pretty cool John! nice job, did you try to wring them together?
Yes, it would be the icing on the cake
Lol, can't wait to see some turret lathe work.
Make 10 and stack and measure then you'll have an average: it's a touch more accurate. Sparking out is pretty critical when grinding really counts. Othertimes no not so much, you do what you think makes sense. I would spark out a gage block. Lots of cool stuff in this video!
NYC CNC I don't wanna hurt feelings here. Sparking out won't matter on a Tormach(or most of what I see on youtube). When you can consistently measure a tenth(which is a joke among toolmakers) sparking out will make a difference. In a plant like GM or Alcoa or Deere tenths can be measured and removed. The small shop working for these companies know their limits; some can get very accurate work out- within a tenth. Sparking out is a given with grinding equipment. Those grinders are worth as much as your whole shop. It's an unfair comparison.
Spring in thin parts is a B. Good luck with that!
This is all way above my experience and pay-grade FYI. I have a heck-of-a-dad. Sometimes tho what he says and what younger guys are doing doesn't match up. Old toolmakers wrote the book, but they didn't finish it. You are a great innovator, picking up where they left off. Tormach is very exciting and I enjoy learning from some of your toolpaths that you setup.
You've also made a believer out of me as far as Tormach goes. When I retire I hope to find some nicely used Tormach equipment... in 30 years that is.
NYC CNC One more thing. When folks on YT are running a BP and talking about removing a thou they are talking out their asses. A thou on a BP is almost impossible. You simply cannot get enough tool pressure to cut that and remain accurate on a BP. That I do know from experience. You gotta be able to measure what it is you are machining. And machine rigidity for Pete's sake! Most folks miss that part and trust the dials to do the measuring for them. I'll go back to my hole now for the day; back where I belong. Stop watching Fenner. Period. I'm not a hater, just practical is all. Guess-work is not machine-work. Working without tolerances is lazy and impractical.
NYC CNC and I don't know enough to talk on the subject. I know what is practical; I am not on this subject.
Stacking would give you the average essentially, but would not tell if even one of them was to size?
That is correct. If each block is 0.0005 over it is easier to find when 10 are stacked and measured. Also a high spot shows up when they are stacked. Adjust and make a final part.
If you love grinding, you need to pickup a manual grinder. A lot more versatile than this toy (sry to say) you'll be grinding angles and radi in no time! :)
$25 is too much to spend on a real gage block with micron accuracy what is your hourly shop rate, it looks like you spent 2 hours on that project between the programming milling sawing and grinding I think you just made under $15 an hour including shop overhead or about $7.50/hr. Plus you didn't get a micron accuracy gage block just a placeholder that probably won't wring without lapping. Nice try but I don't think you made a gage block sorry....
Nice work, I really enjoyed watching that! Thanks
Buddy
You missed one thing, you should have put them together to see how well they stick :)
But do they wring together??? That's the question.
Will that new block adhere to the others if you need to stack the blocks? Do the other blocks adhere to each other? Sorry, I know adhere isn't the right term, but was just curious on whether they have to do something special to gage blocks to get them to be able to do that.
NYC CNC When gage blocks "stick" to each other it is a phenomenon known as wringing, which is a combination of pressing the air out and a thin film of "unknown" composition. It requires an exceedingly flat and highly lapped surface.
www.aspe.net/publications/Annual_2005/POSTERS/3METRO/6SURF/1831.PDF
atomkinder67
I believe that it has also been argued, though not by anyone as uneducated as myself, that wringing may induce a form of van der Waals' interaction in the surfaces via the static one imparts into the gauge block during the wiping of it across your wrist. I haven't the article to quote, but did discuss it with Tom Lipton, and he's pretty much bathed in science daily ;)
Cool project, and I had wondered if you were going to lapp the block after surface grinding, and if so how you would do so in an accurate manner, or "on plane".
I guess I've got my homework for tonight...Aloha, Chuck
Knolltop Farms In a lab environment gage blocks are never touched with bare hands. Very common to wear cotton gloves to partially insulate high grade blocks from the heat of one's hands.
atomkinder67
Most gage blocks are hand or machine lapped to submicron so that they will wring together.
gbowne1 As a micron is just shy of .00004" I would hope so. This depends on grade though and block length. Lab grade gage blocks one inch and under have to be within .000009" of nominal size IIRC. That's total tolerance, not +/-.
How precise do you think it would be had you just milled it. About a thou or 2?
+NYC CNC I would expect you could get down to a thou or less on the Tormach with a flycutter and the appropriate feeds and speeds, and manual setting of the Z axis with indicators. It would be an interesting experiment to see what you can get out of the machine.
If yo profiled the part with the .107 in Y and cut and measured you should be able to get it within a couple of tenths just with a milled finish. I wouldn't se tool deflection being an issue over something the length of a slip. Run a spring pass, clock the tool.
You can do electro etching with vinegar, battery and printout from a laserprinter. =)
Its quite a good way of marking tools actually. You can do stencils out of plastic as well then set one pole to the material, and sponge with a clamp to the other pole and dip it in vinegar then slowly rubbing through the stencil marking the part. =)
Print with a laser on overhead film (old school plastic film) and then take a excato knife to it.. in your case.. spray glue it to something, take a reeaaaaly small mill.. and well.. mill it..
NYC CNC Try this mate.
1. Use Photoshop or a similar program to create a reverse image of the numbers you want to print on the gauge block.
2. Print a black and white image of the numbers using a hi res laser printer onto a sheet of white copy paper. (Don't use photo paper.)
3. Clean the steel gauge block thoroughly with acetone or isopropyl alcohol.
4. Using a hot clothes iron, transfer the image to the gauge block. (The toner comprising the image will melt and stick to the steel of the gauge block... Well, it should.)
5. Peel the paper off the block carefully and if there are any exclusions, dab a bit of girl type fingernail paint onto the exclusions with a real small, fine brush.
6. Using another real fine brush or a bit of cotton wool twirled round the end of a tooth pick, dab ferric chloride onto the exposed steel that you need to etch. You should be able to get ferric chloride at one of your Radio Shack stores.
7. Gently wash off the etchant after five minutes or so and inspect the result. If you are not satisfied, gently apply more ferric chlorids and wait a few more minutes before washing off. Repeat as necessary. The ferric chloride should etch the exposed steel pretty well and leave a high contrast result. . Well it should.
Yair... That's about it I reckon.
Cheers.
PS You do good stuff.
Better than nothing but it won't wring and will be a pain to use.
I know it might not be the appropriate place to ask this, but what kind of an education do you need to learn about machining and designing mechanical parts / machines with cnc / machining equipment?
Im also self learner, came in to metalworking 4y ago with 0% experience. Now I run 2x CNC milling machines, doing setup and programming from start to finish. Best place to learn is a machine shop ;)
What is the theory behind the granite block? wouldn't a steel block be better in the long term?
Granite is harder than steel, and far, far more dimensionally stable. There are cast iron surface plates as well, but they are generally hand-scraped very, very flat, and are used commonly for lapping operations.
Granite is more stable in variable heat conditions etc.
@4:00 Did someone start welding nearby?
You should've rung them to show accuracy
Does it wring?
I am very disappointed in this video. It"s OK to make a quick and dirty replacement for a missing game block but it must be clearly understood by all that is what you are doing for the start pending arrival of the calibrated and certified article. Further, a quick and dirty gauge block must be made of good stuff you can harden to Rc 60. 4141 as quenched in oil goes to Rc 50-55.
Leave off all the process control, lapping etc. You can check a 0.107 gauge block by stacking a 0.103 block on a 0.104.and stack the block you are making on 0.100. Working from a granite flat and using a gauge head and gage amplifier you can certify parallelism and size to the limits of your apparatus BUT the best you can do is make the block, determine its size to 0.0001" etch the actual size on the block, and use it only until the certified calibrated block arrives. THEN you deface and scrap the bogus block.
I know this is just to see if you can make a gage block. Of course you can. Most any machinist or tool maker can, with a little care, make a close approximation of a gage block for a special purpose. In my year in the motor shop I dug up a dozen defunct ring gages and repurposed them to suit common ball bearing outer race dias. But these were plainly marked "NOT CALIBRATED! PROCESS USE ONLY. DO NOT USE FOR FINAL ACCEPTANCE!" That they were round to 15 millionths, had mirror lapped gaging surfaces, and marked for size to 50 millionths meant nothing to the QA people. They weren't in the cal and cert program. PERIOD.
Deceptive looking home made gage blocks are anathema to any QA program. It's a bad apple whose presence raises doubt about how precision tooling certification and consequent product quality is assured within the organization using it. If discovered and denounced by a reputable third party your entire QA effort will fall in instant disrepute. Legal and financial consequences may follow. Shars gage blocks ain't bad for open shop use. I got Metric and Imperial and a set of Mitutoyo gage block attachments but I wouldn't use them to certify any work to tolerances closer than +/- 0.0003".
Sorry this wound up a lecture. Make your gage block, demo your process, plainly and loudly declare it a demo/expedient, deface and trash it when you're done, and spend the money to buy a certifiable replacement 0.107 gage block.
Noobs are watching. You are a recognized source of machine shop lore: you have responsibilities you may not have anticipated.
Make your own gages to suit your work. But never slip a home brew duplicate where it might be mistaken for the genuine calibrated article.
Thanks for this.
T. Noob
But do they stick?
Thanks! Great video.
Outstanding!
Should've left it two tenths big and lapped it, it won't wring very well off the grinder. Too high of a RA
lol, "i dont want to offend someone that overthinks this stuff" a little passive aggressive but ill buy it ;)
Striations. I would go for that word.
So that is +\- 50 millionths of a inch and your indicator is only capable of 5 tenth thousands. So yea it really wont be a gauge block certified although with a good ground mirror finish if it wrings together your flatness is gonna be gage quality. It u will have no way to certify it.... now on the flip side u and i both know that if u are within .0002" or better yet .0001" u are more accurate than most any job will ever call for. It is just the entire
Point of a gage block is to be more accurate than anything u can create aside from grinding.
Also it needs to be seasoned steel heat treated to 65 Hrc so 4140 lre hard is only 30Hrc and that is not even close to hard enough. A2 tool steel hardened and tempered at the lowest temper range will yeild 60hrc so that will work and even better yet S7 tool steel will get to 65Hrc.
Ummmm, a small part like that should really be blocked in with parallels etc!
I"m amazed
O sold half my tool to eat
The trade has not been to good for me where im at. I need $and hours
i can make you one if you want and can send a cert with it i work at vermont gage and we make thing like this and measure down to .00002
NYC CNC
chevalier cnc surface grinders climate controlled also parts are frozen to restructure the steal so it will always return back to it size in a nut shell
Great video. Check out Suburbon Tool on UA-cam, they have a series on surface grinder that is excellent. Dave
No wringing test? Sniff... ;-) !!
Your measuring in 0.001” which is absurdly coarse for a gauge block, how about for starters using a 0.001 Millimeter gauge?
These things are measured in light wavelengths and you are trying to make one with a ruler.
1 thou equals 1/200 millimeter /0.0254 millimeter while a metric “thou” equals 1/1000 of a millimeter or 0.001mm and a gauge for measuring that can be found worldwide at just about any hardware/toolstore, but apperently not in the usa.
But he!? , 1 thou sounds cool and sounds quite accurate.