Most of these threads are years old, and I just know you guys change equipment more often than that. I am going to be looking at building a muller and wanted to see what kinds y'all are using these days. While I had good success with the "Tarp Stomp" method, I wanted to build something and try to reinvent yet another wheel (pun intended). Thinking of getting a 55 gallon drum to start. WAY overkill for a hobby operation, but I do exist to make sure the word OVERKILL gets used more often than it does today.... I make things, and I experiment, because I can. Where's the fun in just recreating what someone else recreated? I really miss the KEG I had in Kentucky, that was the perfect size for a muller for my little operation.
Currently I am using a small HF concrete mixer and one of a selection of round rocks. I think it's time for the annual refresher course on muller safety courtesy of @HT1 :
Mine is a cement mixer conversion, very similar to HT1's or this guy's: I went out and got a couple pics of mine for you: Note the texture I had to grind into the wear plate along the wheel's path, after chewing up petrobond for a couple of years had it sanded smooth and well oiled. It got to the point where the sand would just pile up in front of the wheel and slide, rather than keep moving forward and getting rolled over. It took a while before this texturing was necessary. I think that idea was Petee's, anyhow it worked like a charm. The one way mine is different from other cement mixer conversions is that my wheel is being pushed rather than pulled. More sand makes it want to press down harder not lift up. I did not built it this way intentionally, it's just the only way I could get the wheel to fit after I installed the plows. I have mixed feelings about it. It works well and I don't need any springs or weights to hold the wheel down, but occasionally if I put in a little too much sand, it'll pull down right to the wear plate so hard it'll stall out the muller and I'll have to turn off in a hurry and roll it by hand back half a turn (and maybe take out some sand, or not) before restarting it. So I don't like to let it run unattended. 20 pounds of dry ingredients is the biggest batch size that it seems to like for making new greensand or K-bond sand using this 8" OD wheel. It seems to like about a half a bucket of used sand per load when reconditioning. You also asked for video, so here goes. This is pretty recent and there's several angles of the muller shown in operation, hope it helps. I have a friend who uses an unmodified cement mixer and a large heavy rock and a length of chain thrown in with the sand, similar to what some others on here are doing. His can process a little more sand at time than my muller can, but to my knowledge he's only maintained his few hundred pounds of sand through around 20-25 castings so far. From what others here have posted about their big rock in a cement mixer mullers, I expect it'll be able to keep his sand in good shape for a long time, but I can't say how well it'd work for making new sand. Someone who's actually tried that would know more. Anyhow, I like mine so much I have a second one half built. Actually someone else built it (wrong - he attached the crossbar to the legs not the yoke, so you can't dump it out. Plus the wheels are too skinny to be of any use) and I ended up with it, thinking it'd be nice some day to fix up so I will have one for petrobond and one for greensand. It'd be really nice to have room for 2 mullers too... I created a sand muller (and reasonable alternatives and facsimiles thereof) YouTube playlist for myself. I found enough videos that this only includes part 1's of the different build series I found. Maybe something here will inspire you: https://youtube.com/playlist?list=PLo6k_ZP-VFj6756qw1sxU2jKxrU76a4I6&si=j0IQ9_pdTKEwVBge Good luck! Jeff
My muller is covered in this video... from 7:33. It is only 370W, so it cant do too much sand at once, but will do one of my standard sized flasks of sand. I really should make up a new plough for it, and make it adjustable. A fair amount of sand gets smooshed against the wall and sticks there. It would be more efficient if the plough would scrape that better. However it does a really nice job on the sand. It comes out nice and fluffy.
This came to me as a rotating table out of a production facility for assembling, gathering, playing checkers, who knows. The table top was about 5 ft in diameter. I simply cut the table diameter down with a jig saw and fabricated/installed the drum, plows and wheel, and speed control linkage. I say simply, but every aspect of it was quite a project. The motor is interesting in that it is a variable speed AC motor. It also goes in reverse but I don’t need to do that. I can get about 50lbs in there. Lots of room for dumping and scooping. I originally got the idea from an Ironsides video, and when I saw the table for sale from one of my printing equipment auction sites I snagged it. This is my first muller made from the George VonTorne design available online. Works great for greensand but not so much for petrobond. That’s why I made the rotating muller shown above. Pete
Many thanks folks! I bought 55 gal drums for $10 each and I have found SO MUCH use for them! First being, the drum for a muller, however I have realized the extra metal cut from the middle, being 1mm thick, malleable and very weldable, I have been able to make a body for my first ribbon burner quite easily. Anyway, not to derail my own thread. One section of a drum, on semi-industrial casters, it spins freely and nicely. It can derail itself. I built a ('gantry'?) and was able to hang some pretty heavy weight from it to suspend into the barrel. I was able to suspend almost a hundred pounds of weight off it. Yeah, that ain't even gonna work. From perusing all your videos, as well as anything I can find on the interwebs, the wheel/blades have to be solid built, not 'floppy'. I have not figured out the drive train for it. I re-wired a 3/4 HP motor last night and it seems beefy enough to do what I want. No gear box handy, yet, to be able to transfer power. Thinking of a setup with the tub FIXED, motor/gearing/belting on the top with the wheel/scrapers hanging down, that unit attached to the sides of the tub. This is appealing as it allows there to be a trap door for emptying the muller which I love the idea of.
Worked a lot on the muller, or more importantly the engineering of "A" muller. I forgot I had an old 55gal drum stirrer. That had a half inch upper section I could flip over a socket and then use a bolt as the driver with. The lower section had another piece welded over it. I had some 1 inch thick-walled aluminum tubing I cut out recesses it could press fit into to act as a steady for the bottom. Almost handled two 5gal buckets full with a simple hand drill It's coming together....Now to find a blasted 90 degree gearbox.
Posting pics of the Mini-Mite I inherited from my father. If you are interested in it I just posted it in the for sale section.
@Paul Martinson welcome to the forum and nice muller! Those do a great job, perfect for an avid hobbyist. The neighbor a few doors down has a treadmill in a free pile. Treadmills make good donors for mullers, right? M-u-s-t r-e-s-i-s-t starting another project...
Well, I've always kind of cheated and used these auger type drills. I used a small one, about 2" Dia., then found this larger one, a little over 3 inches. It works pretty well. I mix the sand for good amount of time and then dump it into another bucket and mix it some more. I have 2 buckets of Petro bond and 2 buckets of green sand. Works well on both.
Here my makeshift sand muller: just a cheap cordless drill and a cement / stucco mixer for preparing the sand befor molding.
