ucki

Long time no post! I've almost completed my machine, it's only missing one outer panel. After the first few test runs it was evident that a engine protection circuit or whatever it is called in english was required, also the feeding mechanism is to noisy and unreliable, so i'll have modify that or change to a more conventional vise-type contraption... BUT ATLEAST THE DAMN THING IS HEAVY!!! It weighs atleast 40kg empty, so when i add 4 litres of water 1 kilo aluminum scrap and 4kg grinding media It weighs about 50 kg! fortunately it has wheels... i'll try to get some photo's of the damn thing soon, any suggestion or evident design flaws can pointed out and will be appriciated.. The main thing is that it works! after less than one hour of sporadic grinding during the first testing, the grinder produced 100 grams of easily separatable ( d'onno if dats a woordd) coarser Al and around 40grams of uber fine stuff that was a bitch to separate, so i didn't Anyways, after next week when schools basically over i'll start to improve the damn thing and i'll try make some thermite in the process. I just bought a 2kg cap digital scale that has 1 gram resolution so that will be a great help when mixing that shit up, earlier i've just questimated or used an antique mechanical scale... BTW how long do you guys think i'll need to mix the thermite mixture in ball mill?

To be exact i wasn't going to use an actual "paper" sand paper , it's really a cloth or textile backed stuff... I guess i could coat it with self-vulcanizing rubber of sorts... my concern is that ,when i increase the outer diameter of the drum i also would increase the tangential velocity(?) (can't be bothered to check if that's the correct term) which would lead to splashing the coolant water all over and making a mess of the damn thing.. Well i'm going to the school next week, even if it is winter break and i'm gonna build the feeding mechanism for the grinder and i'll try get started on the outer casing.. I'll try post pics for this post if i'll try to coat the drum with corundum or with some other grinding media...

Hi i was just wondering that has anyone here tried to replace the sand paper with for example , epoxy-SiC paste, i think it would be a lot more cost effective, i just found a site that sells SiC powder in 500g bags for just 7 euros, that amount of 80 mesh powder would last a long time, and you could glue several layers on to the drum, two or three millimeters of that stuff would grind for ever... and it would look a lot more industrial The only problem would be choosing the correct epoxy resin , because there is lot's of differences between them, and i doubt the manufacturers would give away their secrets.... Reason why i am considering this is my concern regarding the performance of the tape i would be using to attach the sanding paper to the drum in cold and wet condiions it would be put through

well today i got everything bolted to the frame and i also forgot to bring the motor's wiring , so i was force to turn the damn thing by hand... this of course resulted a sore finger or to and almost a blister, it's still pretty fucking noisy, but at least the chain stopped jumping after aligned and tensioned the chain properly... This the first time i've run a moped chain without a noisy combustion engine attached to it, so really don't know how quiet can be, i suspect that the tiny 9 tooth motor sprocket is the main reason for the vibration and noise, it's now contacting the chain 150-170 degrees , it should get quieter if i can reduce the angle of attack? now i'm starting to get some regrets , i propably would have better of with toothed belt or with a V belt, but getting the running gear for those would have much more expensive, unless i would have able to find the correct sizes from scrapped car engines... 9:15:58 propably isn't too common in vehicle accessory devices. But if the noise doesn't cause premature failure of the motor or any of the sprockets or bearings it really doesn't matter to me, i'm not gonna run indoors anyways, and i was going to sound-proof it's casing anyway. i'll try to get decent video of the damn thing running in the near future. Now all i have to do is to fine tune everything and make the feeding mechanism and water tray for the grinder, that's about 6 to 12 hours of work and of course the frame and panels for the casing and the hatches all 4 of them for the casing. have a nice weekend ya'll! i'm gonna get my drink on...

Hello evripadi! I finished the motor-mount and the chain tensioning mechanism yesterday and i did a little mock-up mounting i also made the axels and bearing mounts for the ball mill, the mounts are actually still lacking their flanges , mainly because the damn tensioning mechanism gave me so much grief . Anyways here are some crappy pics of my progress... Only thing missing besides the bearing mount flanges, is the ball mills sprocket, when i get those done i'll be able to align everything up and do the first test run...finally! The steel sheet floors that i welded to the frame are pretty crappy , but i was in a lot of pain that day and all those ibuprofen and parasetamols really affected my concentration ... (don't eat more than 1500mg of those at once ) yady yady yaa explain explain explain!!!

My back has been killing me this week and to make matters worse my computer's HD broke, 2 procents of bad sectors or like the germans say it iz kaputt But now i have a new, much quieter and faster PC, but i had to go to work today and again tomorrow so i am able to pay for the damn thing... traded in the old and still had to pay 550 euros, but these shop that actually give you some money for your old equipment are few and far apart or something like that.. And to answer your question concercing my whereabouts, i can only say that it is sad to see that a real bonafide Californian can be fooled by a mere Finn... I didn't realize that my english is that good... I know of the governator-thing because i watch Conando on telemundo or was it Late night with Cornhole O'Bunion ??? And i follow world events (in horror), especially events concerning the WPD (World Police Department) also known as the Americans. So, no i'm not an American , i'm from the Soviet republic of Finland , from near the south eastern border , that's all the personal info you'll get from me, for now. The project hasn't advanced much this week, i've begun making the chain tensioning mechanism and i made a floor out of 1mm sheet steel to the frame , i'll try to take pics next week again and i'll hopefully have running at end of the week, keep your fingers crossed if you give a shite :P

No phots this weekend, sorry guys, my back was killing me yesterday, and i had to leave after only 3 hrs of work... It really isn't pleasent to work when you are dripping with sweat because of the constant agony and stabbing pain... And drive home wasn't lovely either, i have thank my lucky stars or something that i even made it back, every bumb and turn was just a pain filled and agony encrusted piece of cake... Plus the weather was awful, couple of people had slid and slided their cars out of the highway, luckily there were no casualties, only bruised egos.. I only managed to complete the bearing mounts for the grinder and i started to make a sheet metal floor and sides between the main frame rails. Today i modified the design of the chain tensioning mechanism, i simplified them considerably and they are now probably easier to fabricate and will function better.. me hopes Nowadays it doesn't suprise me as much as it used to, that my best ideas come to me just as i'm waking up or going to sleep, i always keep a pen and paper near my bed so i can write and draw them down...

Yeah but when i last used it i was under a strict schedule and hurrying is not for TIG... But i guess now when i can do at my own pace it really isn't that hard, and the great thing about tig is that you can't make mistakes that fast ... It really is the best choice when u r unable to machine the welded areas .. BTW i finally got the motors small sprocket done right and the bearing mounts are almost finished the only thing left to do to them tomorrow, is to weld the mounting flanges to them... I wish i was more of a perfectionist, the photos and this whole darn thing would have been much prettier, but i very rarely do anything perfect, "just right" or "close enough" suites me better... Functionality has always the priority to me in my projects, the aesthetics i leave for the artist and designers. I'm just a metal grunt, all go no show . I must apologize for my gibberish , i'm very tired and dehydraded I'll take some pics of the "banana" frame and the other scrap i've been producing this week for the forum tomorrow , until then it's bye bye and nighty night.

Tungsten Inert Welding has not being used during this project, although today it would have been the best choice, because when i welded up my machine's base frame (using a massive 500amp MAG with an attitude), the main mounting rails arced about 3mm at the middle , that mistake could be fixed by simply hot spotting the tubing from the opposite side (with a blowtorch or ace-oxy torch) compared to the original heated area which caused the tubes or rails to warp. But the warping is symmetrical and propably doesn't cause any problems so the damage really is only cosmetic.... Heat warpage is bitch, i remember when i was building my gun safe i warped the door of the safe because i forgot to weld it in the right order, i should have welded the crowbar-shield to door using a certain sequence instead i rushed things too fast and welded the seam from end to end... the result was 4 hours of hot spotting and using a 20lb sledge hammer to straighthen the damn door. If anyone here didn't understand any of this this link might help: http://www.welding-advisers.com/Welding-distortion.html The good thing about working with steel is that most of the time you can fix whatever you have F*cked up IF you know the tricks...(and that very often is a BIG IF) I'll maybe use TIG when i'll weld the bearing mounts and if i'll do the water tray out of SS sheet i will have no choice but use the dreaded Ti Aiiight Ge (5 years has passed from the last time i used TIG, so i'm a bit scared of the damn thing...) I have welded lots of delicate objects with Mag , even pressure vessels , but my schools metal lab doesn't have SS MAG wire, so really can't use it for making the tray.. I'm sorry to have to point out to you SoulPredator that those welds of mine are pretty rubbish, but luckily the amount of stress they will have endure is quite puny, so the quality of the welds really doesn't matter. Practise makes perfect i guess and John Practise makes divine. (P.S. you have to pronounce john practice "Jaauuuhhn Prauyctiz" , because that's the Governator way..) Oh now i see why you thought that it was TIG welded, the seams seem so smooth because the drums ends were machined after the welding, so sorry no pipe welding machines or super welding skillz here... Okay now i really have to quit again, because my stories are coming too complex and incoherent. I'll try post more pics this weekend and hopefully i'll have the damn thing spinning along next week. here is the ugly truth in high def.... :P

Well finally i remembered to take my camera with me to the lab... Finished the adapter for the grinding drums sprocket i also managed to ruin the electric motor's 9 teeth sprocket , the rotation center changed, because i removed the axel for the welding work and i didn't notice the miss-aligment before it was too late (after i drilled the hole for the motor's axel), and my attempts to rectify the mistake only made it worse, so 5 euros worth of sprocket is now scrap... oh well now i have a new idiot-proof (yeah me stuupid) working sequence, which should eliminate the possibility of miss-aligment. anyway here are the new photos showing the grinding drum, axel, sprocket, sprocket adapter and bearings.. Next job will be the frame or the bearing housings for the drum's bearings... Yesterday i came up with the plans for the grinder's feeding mechanism , let's just say it will look suprisingly much like the feeding mechanisms of some blenders , i'll also make it sectioned so i can control wear of the drum and target for example only 25 percent of the drums surface. It sounds bit complicated but really shouldn't be more than two hours of welding and buzzing around with the venerable angle grinder :(

well, the grinding drum is complete, and so is it's axel, the drum has 0.4mm of radial throw in it, but i'll test it for awhile, and see if it causes any problems... i'm just too lazy to be bothered to fix it just because it is not perfect... I forgot my camera again so i won't be posting any new pix this weekend, sorry. I only worked for 3 hours so I guess I can forgive myself for not getting anymore done than that. Man the weather here is awful, visibility on the highway was like 20 meters , and the sidewind was pretty stiff, but i can't complain, when i consider what kind weather you guys in middle-europe have had thanks for the feedback and info, it will save me time and money, mainly because i don't have to buy any more copper or brass , that shit is EXPENSIVE.... I'll most likely use mix of copper and inox tubular bar for grinding media... I think i saw several meters of ^12mm SS in the machining labs warehouse, so that won't cost me anything, it's pretty nice that we use every material in the lab for our own projects, i should have modified my plans in way that i could get everything i need from the lab, now this machine is going to cost me around 150 euros, which still pretty cheap, considering that the cheapest ball mill i saw for sale in my country is 600 euros, and additional drums (ceramic) cost 100-300 euros a piece . Bye for now have a nice and SAFE weekend you all!

thx a lot , that sounds plausible... , i'm also considering adding some glass spheres to my grinding media arsenal, when i was a kid i bought a big bag of glass balls from trinket shop, i wonder where i put them? maybe i'll run copper bits with both brass coins and glass spheres, atleast it will be loud!! I'm also getting mixed info about using stainless steel grinding medium for aluminium, what's verdict on that my fellow pyroes? About the grinding drum, i'll propably use 40grit 30mm wide sanding paper on the surface, what do you guys recommend for attaching it to the drums surface? hot glue, epoxy , some sort mechanism or what? or duct tape BTW I love duct tape, it's great stuff, especially for my pneumatic cannon's projectiles, i have a same sort of CNG-rated tubing for it's barrel and it's inner diameter is 70mm and soda can diameter is (if i remember correctly) 66.8? so some sealing is required, that's where duct tape and plastic foam comes handy... I really have build second this year, maybe a portable one, the old one weighs 30kilos and that's excluding the chassis or the base...Now i have to stop writing because i'm getting sidetracked big time. ;)

Oh i just remembered what i was supposed to ask yesterday... I was just wondering if anyone here has mixed thermite compositions in a ball mill... and i really mean only mixing the already pulverized components together with no grinding media.. Is there a possibility that it will ignite? Is that that possibility very high or one in a billion? I'm just trying to visualize the mechanics involved in that mixing process and it's hard to imagine that they would ignite, of course static discharge can ignite anything that has sufficiently low mass and/or low mass to surface area ratio... if anyone has personal experiences or links to hard fact and research by professional, i'd love see it. I'm not interested in BFBS ( Basic.Forum.Bull.Shit) or semi-fictional hearsay...

I almost finished the grinder roll... It's bit of an overkill, weighing about 4 kilos. Tomorrow I'm buying a 20mm drawn axel for it and with that i'm able to align those drum post up, after properly aligning them , i'll slide the jacket (red CNG-rated steel pipe shown in the pics) over the post and weld it to them... Sorry about the poor quality of the pics, I forgot my camera at home , so I had to use my cell phone. I'll try weld up the basic frame of the device tomorrow as well. Man it's pretty weird to be the LAST person to leave the school , usually i'm among the first to bolt, because most of the stuff and the staff in that school is pretty lame, so i get bored..... Fast!, luckily i have no courses tomorrow so i'll be able to help my friends at the CNC lathe and do my own thang...... I thought that ball milling took only 12 to 24 hours, when using fine enough powder my electrical bill will go through the roof if i have to run that motor continously for a week... that's like atleast 100watts per hour... so week would be 7x24x0.1kw=16.8 kwh electricity costs here about 0.06€ per kwh so 16.8x0.06€= ~1euro!!! OMG! i'll be bankrupt BTW my order for boric acid and pigment grade fe304 arrived today ... 1kg of boric and 5 kg of black rust and five of the brownish kind... it's actually made in Holland or atleast it's called Holland rust... the black stuff is 96-98 procent fe304 and 600mesh , the brown stuff is a bit coarser... hopefully it's not too fine i don't want flash thermite, it won't penetrate as good. I ordered all that shit from a big ceramic store. They had all sorts of metal oxides and chromates in their selection. So i'll most likely add some more pictures this weekend i'll also try describe the different phases of the construction as well.

I just used google for the thickness, i'm gonna check it with a micrometer later today.... Oh BTW i'm planning to use cylindrical copper bar 10mm diameter.... I found 900mm of it in our basement, so i'll probably cut it to about 80 pieces... I do have foreign outdated coins that i could use also.. but i'm not that sure if they'll tumble correctly, i'll probably mod the ball mill tube so that it will have some collider flanges inside it so maybe they'll work better after that.

Hi ! I'm in the process of building a ball mill- grinder combo machine, i'll try to post a few pics of the project and the different parts of the machine in the near future... , this week i'll probably finish making the grinding drum and the chassis of the machine. I'm using a 350W@1450rpm electric motor in it and a chain drive.. It's a fun little project that will refresh my rusted machining and welding skills and will able me to make lots and lots of THERMITE!!! Mmmmmm....thermite.... Today I bought the neccessary sprockets for the machine and i'll try to mod them to my needs. I also "nicked" 3kilos of aluminium scrap from my polytechs machining lab... There is also a 100kilo roll of aluminium foil there, but I think they would notice if I started hauling that stuff out of there, besides it's fairly thick, so I don't it's worth the effort. I calcumated that a your run-of-the-mill kitchen foil roll (290x1500x0.10?) contains about 300grams of that sweet sweet Al so i'll settle for that if need be... Wish me luck, i'll need it! :(