Making a Real Frame! - DIY CNC Metal Lathe Build! #2 

I think I'd go with the sand / gravel mix but without epoxy so there would be a possibility to remove the it if necessary

@@GBWM_CNC go for it

@@GBWM_CNC Sand with thick motor oil.

@@tugrulcagr7640 that would sound interesting

@@GBWM_CNC It will also give you thermal stability. Gets hot or cold more evenly.

Hi! That's a good hint! I'll consider mixing up sand and gravel for that!

Epoxy granite maybe

​@@GBWM_CNC There is a series of videos on RU-vid about a prof of mechanical engineering iirc. He has an Air Bearing lathe with the bed made from granite parallels epoxied together.

Sika Grout have ready to go no shrinkage mixes for that , they designed to repleace epoxy granite etc , cost fraction of epoxy granite mix

@@ErtsenPlayGames Could you post a link to it or tell me the exact name?

This is why is hard to make a welded structure , if u dont have tools to make it , all can weld , but not all have the tools to make stress relief , and make a good structure for a good cnc .

But how to do it with a big steel structure? Does heating with a butane torch would help? Regards

@@matthiashilber2043 se manda a talleres especificos que tienes hornos grandes para eliminar tensiones y con un costo muy economico..el alivio de stres en piezas soldadas es el dia a dia en la industria del mecanizado

@@matthiashilber2043 any heat that will reach its annealing temperature will help, starting at about 260degC.. better than not doing anything at all. the aim is to reach the annealing temperature uniformly, hold it for a while. and cooling down to room temperature very slowly.. you'll need a very good heat insulation. for days if possible. annealing only at slightly higher than 260degC with proper technique really help tremendously. but in a precision machine production, they tend to age the structure like for months or even years. they really let it rust outdoor. but then, actually its not that hard. for mild steel this thick and size a simple hitting with hammer is proven to speed up relief some of the stress, and it does help a lot.. you just don't want your structure suddenly bowing in unpredicted manner. its like a ticking time bomb, and start ticking as you weld. when this machine finished and start to introduce vibration like from rotation of the spindle or the tool without proper stress relief it will definitely release some of the stress and will start to change its geometry. if its me. I'll do whatever i can and keep measuring its critical dimension for days and after each try. and keep trying until its stable to a degree that is acceptable. you'll never know until you really try yourself. i wish you good luck trying.

It helps , best is if u make it , weld , and let it for a 1 year to settle if u dont have an oven to heat it .

¡Me alegra mucho oír eso, jaja! :)

Mulțumiri! Ai propriul tău magazin sau lucrezi într-o fabrică?

Vava la yerba! thanks! :)

¡Estoy haciendo mi mejor esfuerzo! :)

I'm not 100% sure but I've heard some manufacturers actually produce such machines :D

thank you my friend! :)

Sure. Well actually the weld usually pulls the welded piece in the direction of the weld just when the material starts to shrink. I'm not a professional in my opinion, but from my experience sometimes when I see the angle get's in one direction - welding on the opposite corner helps to straighten it up. Also when welding such a frame it helps to weld some welds from one side of the frame and then turn it around and weld the other side so all the stress is kind of canceled during the process. That takes a lot of experience to do it properly (i'm lacking still experience) but it is possible to somehow control the stress in the material. It's also crucial to prevent weld breakage later. Some welders also do preheat the material before welding, so there is less heat input stress involved during the welding (the stress is caused by temperature differences in different zones of the material - the material shrinks in different time which causes stress and therefore deflection). This is what I observed during some of my work - hopefully I'm not writing any stupid things here - haha! :) Maybe I'll make a video someday showing some examples what happens when material is welded and the deflection occours.

@@GBWM_CNC This makes sense. Thanks for the explanation! Rewatching the video, I seem to understand what you did. Welding distortion seems like the final boss of welding to me ;) Looking forward to the next part of the build! I was lucky enough to find an old lathe bed for my own cnc build, but DIY is much more exciting!

@@lordlorz i was thinking about the same. Hopefully you're going to mount linear rails instead of using the factory rails?

i think its always best to get it done in one go with work holding changes. How accurate do you want your ways? if it were me, i'd get a price for a bigger machine to do it in one setup.

​@@JulianMakes I want it as accurate as possible within reasonable price - I'm trying to keep in mind that it is just a homemade machine made for fun, haha! :) But I think you might be right - it might be worth paying more to get it right

@@GBWM_CNC paga por que el trabajo te lo haga una maquina grande cnc y asi te evitas problemas y ganas tiempo y precision...el dinero del pobre va tres veces a la tienda..un saludo

Chłopie nie wyprowadzisz nigdy geometrii beż narzędzi. Lepiej zapłacić tysiaka i mieć spokój i mnóstwo czasu zaoszczędzone

I think the sand + gravel mix should be good without the epoxy so I'll be able to remove it if needed

Usually I'm spot drilling but the stiff milling machine spindle made me too much confident and I've gone with direct aiming for the right size, haha! :) I'll try to improve next time! :)

thanks! I'm using the drills I have if I can do what I need with them :) About the stress relief - I'm still thinking how to deal with that before milling. Maybe some kind of heating + some hammering. About the milling - I have a possibility to take it to a big milling machine which I'll probably do. I thought initially about milling using 5-6 setups with my metal milling machine but it would be really difficult to set it up each time withing like 0,01mm each time - I was going to try my best but reading all comments over here - people convinced me to not to do it, haha! :)

@@GBWM_CNC afaik the whole part needs to be soaked at ~600 degC for a couple hours and then cooled slowly back to room-temp, ideally in a non-oxygen atmosphere for stress relieving. A one time "kiln" from some cheap brick might do the trick? Without this the subsequent precision milling (or scraping) will be for naught as material removal will lead to the part deforming under it's own stresses.. so yeah. Keep up the good work!

谢谢你的提示！

💪 :)

Definitely!

Thanks but the works isn't finished at all, haha! yes - it's my second one and this time I'm trying to adjust my faults from the first one

Thanks my friend! :)

Intento hacer lo mejor que puedo, pero lamentablemente estoy ocupado con muchas cosas últimamente, por lo que el proyecto avanzará lentamente. ¡La yerba mate es increíble!

Zobaczymy co się okaże, gdy rama trafi do frezowania :) Dzięki i pozdrawiam!

Wszystko wymaga czasu, ale powoli idzie do przodu! :)

obrigado! :)

To są cubitrony. Co prawda nie miałem na celu robić jakiejś ich reklamy, ale one reklamują się same - jedna tarcza wytrzymuje tyle, co kilka innych tarcz a prędkość cięcia widoczna na filmie. Co do wypełnienia, to jeszcze mam z tyłu głowy, że chciałbym mieć potencjalną możliwość opróżnienia tej ramy w razie czego i dlatego myślę nad czymś sypkim zamiast czegoś związanego.

💪😁

@@GBWM_CNC Where are you from? I live in Alba Iulia city, Romania.

@@sergiucioanca8763 Poland over here

:)

merci :)

That would be so cool but I but I'm not the best at using cement - I prefer metal, haha! :) Well, in metal I'm not best too, but i'm giving my best :D

yes!

!!!!!

160A to mało? :D

@@GBWM_CNC a widzisz że spoina nie wtopiona jest i garbata? Pachwina w nabocznej to w najgorszym wypadku płaskie lico ma mieć. Nie wróżę tej maszynie poprawnej pracy jak spawać nie potrafisz. Uchwyt 15, drut pewnie 0.8? I do tego chińska spawarka?

@@Micha-nd1cs owszem, uchwyt 15, drut 0,8 i na domiar złego chińska spawarka :/

@@GBWM_CNC no właśnie, i na gwóźdź do trumny chiński półautomaty zasilany 230v?

@@Micha-nd1cs wszystko się zgadza, no nic to nie spawa :(