Awesome! Thank you very much for sharing. I saw a video a few years back of someone using the same approach for a surface grinder. So basically your setup, but a grinding spindle and wheel instead of a milling spindle. Very cool to see aluminum plates float like that! I also saw a video interviewing the KERN people a few years ago where they flatly stated that they use aluminum because of the better thermal conductivity. You were spot on.
Chasing flatness is always a pain. There was a job i used to do where i milled 25mm off one side of a plate and had to keep 0.1mm flatness over a 300mm square area. Started by cutting the skin off both sides off all the material and leaving them sitting on a flat surface over the weekend, the stress can take some time to release in the material. Skim cutting one of the sides again to remove any remaining bow and then marking that face so i placed it down on the fixture. Key factor here is clamping very gently from the side to not bow the plate, this is much easier with thicker material. This process helped a lot in keeping within the flatness tolerance. However my company changed material supplier and the next batch i did i had some plates with flatness worse than 5mm. Material heat treat and aging play a massive part in making your life easier. Nice job, looking forward to the finished upgrade.
Omg. Your experiences sounds quite extreme. You would expect metal to be solid, but it looks like it behaves just like wood.. One good thing it doesn't change shape with humidity ;) 5mm deviatuon you mentioned is over 300mm?!
@@PiotrFoxWysocki Yes, i put the part on the surface plate and could fit a 5mm slip gauge underneath it at one end. CNC precision banana plates lol. Had to bend them all back straight again with a press
Dedication ;) i just dont know when i would have a time to upgrade it again. And i couldn't look in the mirror knowing i could have done a better job ;) beside i need this machine for work where i make a high-end prototypes. So it will pay off on a long run. Also its highly addictive to see how far i can push my self ;)
Plate stock has more stress than cast plate (tooling plate). Typically you use a softer material for a lap, alum lap for steel, zinc lap for alum. For initial flat milled face double sided sticky tape works well with little distortion. I like what you are doing thought a few points might help.
Thanks for the video, it just show when you really spent a lot of time with granite lapping you get a really good result. I wonder if the aluminum plates where produced from rolling material or was originated from cast aluminum. If it was from rolled material the stress inside the aluminum plate is higher in the rolled direction and properly this stress is partly released over time. Therefor cast aluminum and tempered will stay more flat over time. You could measure the thermal expansion with strain gauge rosettes in 120 degree angle and compensate for this. If you want to find temperature stable material look for Invar material, which has a very low expansion coefficient. Used in microscopes, watches, transducers and in combination with active controlled pietzo elements for movement control.
thanks for the warm words :) aluminium was stretched - T-651. Invar - everyday with you guys i learn something new :D I will look it up and study its properties and i will look for possible applications. thank you for the tip :)
I nearly forgot about your upgrade because there was no video about it recently and now you are already finished. Looking forward to watch all those videos and the final result :)
Fox, this is madness! 😄 I admire Your work and time that you've sacrifice for this. It shows some problems when you're trying to make as precise as you can get aluminium parts for cnc. I'm designing 250x300mm X/Z holder for my fixed gantry milling machine. I was considering PA9 (7075) bought "around the corner" but now i'll think about using precise Gleich plate. Pozdrowienia z Polski ;)
Haha ;) this is sparta! No doubt ;) definitely you should get as best cast plate you can to make your life a bit easier later on. Pozdrowienia z cieplej nowej zelandji :D
I may have missed something but how can the material not move on you when you will drill or mill features ? I mean, is it easier and better to do the scraping before the machining ?
great question, i kinda forget to mention about it in the video. my main goal was to make both sides parallel. in case of the z axis is important so it doesn't travel on an angle or wavy surface. i wanted for the rails to have perfect contact surface. drilling holes don't change the the overall geometry, but cutting slots does. in my further design i cut wide slots for ball screw on both plates, and this made them bow outward from the cut. with the both plates bolted to the rails and blocks, this bow is canceled. obviously it would be better to repeat the process of scraping again once everything is milled out. but the variations are not so bad so i decided to skip it. uniform thickness was much more important for me as it is sandwiched between x axis rails and z axis rails. not sure if it does make much sense, but I'm sure it will, once i will upload the next episode.
Witaj Piotr Wyszła ci fajna maszynka cnc no i pomysłów na testy to ci nie brakuje. Pytanie tylko czy to aluminium które frezowałeś nie wygnie się z czasem , zbierałeś mało może będzie dobrze. Mógłbyś dać linka do sklepu gdzie kupiłeś ten frez z testów nieźle zbierał. Pozdrowienia z mroźnego Poznania.
Wygiac to sie chyba za bardzo to nie wygnie juz. Bardziej mi zalezalo na tej samej grubosci. W nastepnym filmiku wyjasnie na przykladzie. A ten frez to jest 25mm frez do drewna ;) jak ma carbideowe inserty. To da rade i w aluminium ;) Wszystko jedno jaka firma.
Piotr, my viewers send my over. I'm currently building a fdm 3d printer out of an old Johannson CMM! So quite a lot of precise granite, too! I have to relapp an air bearing out of brass and this helped me a lot. Do you have information on how this brasso stuff works? Don't you have fear it might destroy your granite plate? Otherwise it would be an interesting solution to my problem!
brasso is made out of liquid hydrocarbons and ammonia. will it destroy your granite? hmm.. every rubbing action on any surface destroys it. would it be much, i don't think so. In my opinion you have to break some eggs to make a omelet :) if you will use the whole surface of surface plate the difference after you done might be not noticeable. but you have to consider the possibility of resurfacing the plate once you are done.
I have had problems with Russian alluminum in the past so I only use USA made stuff. But what you should have used is mic6, it is meant for fixturing and has very little stress.
In New Zealand our choice is quite limited. And everything cost arm and the leg as most of the products are imported. Maybe i haven't been looking hard enough for anything better. But i haven't seen anything like mic6 before on the market here.
@@PiotrFoxWysocki the number of times I have seen a US turner / woodworker grab a piece of mahogany from his "junk" pile - something that would cost 100s of dollars here in Aus. Eesh. Much jealousy!
thank you :) yes this idea has crossed my mind. but then it would take much longer and i would charge those plates with lapping compound. and when it would come to milling endmill would cut it self on cutting this plate. But i was very tempted especially at the end of sanding where this could potentially help :)
Hey Alex! I'm glad really, really glad you liked it :) I remember when you were talking about making a base for the motion control out of 2 plates with oil in between. you are my old colleague and my favourite director :D I had the best time of my life working with you on the blade runner 2048. I wish there would be another movie like that.
Amazing and incredibly inspiring Fox! Just wondering, is there any way to destress the alu with a heat cycle? Now, don't blush, but what you do is extremely cool, but better yet, your humble approach and not buying into dogmas is such a pleasure. The whole no-frills "production" of the videos prove what too many youtubers forget, that content really is king. That said, well done on making sure we get good audio and it looks like you even lit the "talking head" clips;)
i have no idea. i know when they do extrusions they keep it in the oven for some time. well.. i don't have oven anyway so i wasn't even looking for any information in this field. but if someone with experience would like to comment, it would be cool.
Thank you for the edit ;) Dogma or not. For me the results are more important than an hour of lecture and average results ;) I'm afraid that my content is so specialized that is not digestible by most of the people. I suspect most of the people are more than happy with shapoko or some other cheap hobby machine, cutting wooden gadgets. And those who are more serious are running big milling centers. I'm not planning to change it, becayse it is something what is interesting for me and couple other guys like me. Looks like you also dig this stuff ;) I have to say you do have great eye for details, noticing fill light on my face ;) Lighting in my shop is not best for people but really good for the stuff you work on. Thanks for the warm words, sometimes its good to hear a validation of your work :D
@@PiotrFoxWysocki I am a photographer by trade so could tell you put a bit of work in it. Also, I think you found the best, most quiet corner of your workshop to use a backdrop and it works great and I don't think the measuring tools on the table next to you were placed there by accident;). I mentioned this in another thread, I am building courage/knowledge to build my own machine and I have done some modeling of it already. While others are doing mill type machines out of granite, I actually think I will adopt your router approach with the high sides. I will make it a bit smaller though but since I will be running it in my apartment, I am hoping that the high sides will help keep chips in. Also, I will make it such that I can bolt some acrylic plates to the end and maye even make gaskets/o-rings for those plates so I can make a waterbath for cutting carbon fiber parts. Mostly I will be doing Delrin, Alu and CF but parts will be small and wont be production parts speed is not an issue for me. Just need to be stiff enough to hold some nice tolerances in alu (I'd be happy with +/- 0.05mm). I am supposed to be based in China though stuck long term in the Philippines, but China is an amazing place for building things like these. I can get pretty much all the parts and materials online and delivery is fast and cheap. Also, there are vendors that sell proper quality secondhand servos, rails and ballscrews - often pulled from Japanese machines (I guess you found a good one, too). Once I get back there and manage to top up my bank account again, the build will commence;)
Hey Fox you are a true "tinkerer" with a curious mind. You constantly strive for excellence in short a Masterclass. I have a question, when sourcing granite for cnc for flatness what type should one search for - would off cuts/ discarded kitchentops granite tops be any good?
I went with particular dotted pattern, I suspected that veiny granite might not be as strong. And 50mm granite top should be fine. Note. Counter tops are not as flat as granite surface plates
@@PiotrFoxWysocki I did not realize that the pieces you aquired were surface plates. and not the run of the mill granite blocks. Everyday is a school day for people like us :) Finding secondhand surface plates here in the UK would be challenging but I will begin my search and see where it leads me. Take care my friend down under in NZ.
I have seen cnc machines built on prefinished 20mm thick aluminium base plates produced with less than 0.15mm deviation per metre measuring length. For sure that would be a good choice. I was also thinking along those lines too before I found Fox's interesting channel. It will not be as flat as the granite surface plates which have 4-5 um flatness. That is why with the upgrades Fox has added to the granite base has given him the ability to get an overall accuracy at probably less the 10 um which is would be mighty difficult to match with the high end commercially made machines for the price and size. Hat's off to Fox :)
Hello! It's hard to find any video about flattening / scraping aluminium plates. I'm into the proces of flattening cupped aluminum 3d printer bed. Your input is very educative ! Dzięki z dobre video w dość niepopularnym temacie. Czeka mnie mnóstwo ręcznej roboty, nie mogę stołu zapiąć w maszynę a do zebranie 0,2 mm na brzegach :/ Pozdrawiam,!
powodzenia :) 0.2mm recznie to bedzie masakra. ja caly dzien sie meczylem zeby 0.01mm wyrownac. sprawdzaj na plycie traserskiej co chwile, zeby cie nie ponioslo :)
@@PiotrFoxWysocki Na szczęście praca nie wymaga totalnej precyzji i gładkości na całej powierzchni 235mmx235 mm. I tak dylatacja po włączeniu grzałki zniweczyłaby osiągniętą równość. Będę zadowolony z zejściem do 0.02 0.05 mm
Interesting thought experiment 🤔 On such a large surface it will be the same problem. When you start the cut its straight but when you exit the begining woult distort. So i gues you would have to do couple of passes anyway. Wire might me straight but not sure if the axis along which you will cut is perfectly straight. I think it can be done, but not at once
By measuring the top surface of the plate while the bottom surface is referenced to the surface plate are you not measuring parallelism of the two surfaces relative to each other rather than flatness of the top surface? (Perhaps this makes no difference for your application....) To inspect the flatness of plate surface I think the aluminum plate would have to be supported above the surface plate on three identical height points and the bottom surface of the plate would need to be interrogated with the test indicator.
I guess I took few shortcuts here and there, explaining stuff on camera ain't easy 😉 check the video where I assembled the z axis. I know the theory behind 3 points, white gloves and other metrology black magic. But sometimes I just can't be ... bothered 😉 to me the end result is most important, not the longest path to get there.
@@PiotrFoxWysocki Yes, I understand what you mean. All that matters is that it works for the application. Although parallelism isn’t the same as flatness it’s hard to imagine a non-flat plate floating on the surface plate as you demonstrated. It would be interesting to know, however, how flat you were able to get those plates with the method you demonstrated in the video.
I guess it would. But for very short time and non significant amount. As thermal conductivity of aluminium would absorb and spread the difference uniformly. I guess it would be interesting experiment for some big parts so you can actually measure it.
@@PiotrFoxWysocki Amazing lapping by the way. You should push it further with some optical flats 🤣. On a side note - is the granite surface plate on your CNC resting on 3 points?
Ofcourse I could try optical flats and never finish it 😉 I can live with micron or two 😉 cnc rests on rectangle frame around bezel points. It's a cnc not a measuring instrument.
Not at all ;) next week i will post another video and i will post a link to the 3d model of the machine with all the upgrades. So it might be easier for you to copy things ;)
@@PiotrFoxWysocki you are the man! My friend if you ever visit Serbia you must be my guest of honor. Iam struggling whit a find like you did at the start of yours yurney
