Granite CMM 3D-Prints It's Own Covers + Air Bearing Lapping

[@chronokoks]

To remove almost any mark (bronze, aluminium, bluing paste etc) from granite, use proper strong rubbing with a Radiergummi. Yes, ordinary one with one side blue, the other red/orange/pink/white (white is usually not real rubber. .but it kind of works). Not only pencil eraser's rubber material itself has amazing properties which can clean porous stone materials like granite (it can grab dirt from pores and bring it to the outside surface). It has also pumice mineral abrasives incorporated in it which strengthen the cleaning (abrasive effect on paper) and pumice is softer than granite. If even the vigorous rubbing with the blue side of the eraser (which is more aggressive) won't help, you can always try a Cratex stick that has silicone carbide in it - gentle rubbing needed.

[@Roetz40]

Very interesting, will try to get rid of the last few spots on the granite!

[@chronokoks]

@@Roetz40 Amonia should be used only to remove 3 week old peanut butter stains from the plate ;)

[@GuyFawkes911]

@@chronokoks the blue side contains some grid if I remember correctly

[@chronokoks]

@@GuyFawkes911 Aluminium and brass/brone can be cleaned with the non-blue side too of course. If you're concerned about the abrasive type in the blue side you can always try on hardened steel (which is still softer than granite) and look for scratches.. In my experience most of the normal european brands did not scratch hardened steel (+60hrc).

[@Dr_Petey_Wheatstraw]

Another problem causing warping and lifting is temperature gradients. Not sure the temperature of the shop, but your hands left quite some condensation on the granite so it's probably pretty cold. That's why most decent printers have heated beds, and why high end ones have full enclosures. Very interesting project, I enjoyed following along. Glad everything is working again.

[@Xlaxsauce]

@5:52 we call those "squares" but there are different types and the the type you have we can a "machinists square" was that 1 layer being printed straight up on your case? If so, damn that is awesome

[@Roetz40]

Yes. One extrusion wide, (1.2mm) Worked aweome until lifting... :P

[@hereticswissery9010]

Nice to see everything working again man

[@Roetz40]

Yes, always bad to see project down

[@ChrisTuttle]

Many years ago I discovered accidentally that Accent DRY ERASE MARKERS perfectly remove permanent Sharpie marker ink. Just scribble over Sharpie ink, wait a moment for it to dry, then wipe it away with a dry rag! This is now one of my go to gags to play on friends (and enemies). I would walk up, write on their monitor screen, and watch the horror wash over them. Then like magic, I would do as above and presto, gone-o, and no residue at all. I have not found a surface that couldn't be cleaned this way; glass, whiteboards, office desks, plastic. Your granite table has probably been treated with a sealant to prevent liquids from being absorbed, so I believe this technique will work. Give it a shot! Looking forward to hearing the outcome. Cheers mate! - Chris

[@Nyson]

Very nice. To remove the sharpie marker, you can use Xylene solvent. If it stands up to Xylene, you may have discovered something new. Really like the ideas and videos.

[@maxekb77]

Hello, what’s diameter air hole in bearing ?

[@Audio_Simon]

Is there not a ballscrew support on the repaired axis?

[@Roetz40]

No there isn't. If I stay under 2000rpm it is working great, above that it starts to wobble. But I don't need these high speeds

[@Audio_Simon]

@@Roetz40 Is it lost / missing or not by design? It's kind of shocking to me on such a high accuracy machine to let the screw hang.

[@Audio_Simon]

P.S. love this build and videos! Exciting to see the Kuka.

[@Roetz40]

In the original state there is no ball screw, they did drive the axis by friction. In my case I installed the ball screws for higher acceleration values and easier feedback system. I could support the end but there is a formula on how to determine if you even have to do that. Takes rpm, free hanging length and geometry into account. Mine has critical point at 2.000rpm and I do stay below that anyways since it is a direct drive.

[@Audio_Simon]

@@Roetz40 Thanks for the details. You are talking about the 'critical speed' due to resonance right? I think for the cost of a BF block it may be supported :)

[@Ryan-dz3jo]

Nice work, glad you are happy with the results 👍

[@aleksandarsentice3028]

​ @Roetz 4.0 I joined this video series a little bit late. Wanted to see what went out from the original machine. Like model numbers of linear scales, drives, and maybe some pictures from the control board electronics. Just I enjoy seeing how precision movements are controlled. Is there any documentation for the machine?

[@Roetz40]

I do have full german documentation on the machine but they don't really show how it is built. There is so much know-how involved and you have to be certified anyways so I guess these machines aren't meant to be repaired by yourself. Measurement system is made by teledyne gurley and drives are swiss made dc drives. If there is anything in particular you want to know, post it here. Maybe I can insert that into next video.

[@bill4639]

I always wondered why more CNC machines are not made with air bearings. Why?

[@torstenb5248]

Would a strip of felt at the ends of the air bearing to wipe of any debris be a good idea?

[@Roetz40]

Yes! Either that or some kind of air courtain to keep everything away. But next 20 working hours I'll keep an eye on the debris to make sure there is no contact!

[@SergeiPetrov]

You should try to print a very detailed piece with a 0.1mm nozzle.

[@frollard]

Way late - the servos probably provide more than alarm state, you could use the BTT marlin accessory input to act like a filament runout sensor or other pause function when the motor detects even a few% overcurrent out of tolerance to really catch any problems early. Also, an air-pressure sensor could do the same. If the compressor fails you don't want to ruin the bearings!

[@franziskahilger3268]

Great Video :) Btw - I love your intro!!! What an excellent Idea^^

[@DonStinger]

I guess you mean proud (erhaben) instead of prone (liegend). Also I guess it isn‘t a bad idea to teach the english viewers some german. So guys in this lessons you learned that brass means Messing in german. Although officially it is called Kupfer-Zink-Legierung today which means Copper zinc alloy and is unnecessarily complicated so we germans prefer this of course :)

[@Roetz40]

Hey Markus. Youre 100% right on this one. Thanks for the heads-up! I don't want to know what other words I'm mixing up all the time and have no clue about it :P

[@GuyFawkes911]

what dind of marker is it? ammonia (diluted to roughly 5%) should work, aceton works for most markers, mineral spirits/gas/Benzin/Diesel work OK for waxy compounds. Look at suburban tool (don bailey they clean their surface plates always with ammonia (household which should be 5%) Now I got a question as a german where can I get precision ground stones here (for an OK price)?

[@Roetz40]

Thanks for information, I will check! You can get precision ground stones from Stefan Gotteswinter. Other than that I dont have a shop at hand on where to get them.

[@bent540]

they problem with people measuring like this is they forget all about the other side!