The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Repairing Stone Mill

sewcial's picture
sewcial

Repairing Stone Mill

 Some time back there was discussion of the Marathon Uni Mill. I have had one since 1977 or 78 and have been using it happily ever since with never a problem. However, suddenly, one day, the stones locked up and I can't loosen them.  They just got tight while milling. I turned off the mill and turned them loose bye hand, but, as soon as I turned on the motor, they locked up so tightly that I can't move them at all. The box is so well put together that, even if I remove the bolts, the glue (epoxy, I think) is so secure that I don't know to access the bar between the motor and stones. I have tried an appliance repair person who knew nothing about a stone grinding mill and couldn't suggest who to go to.

Does anyone know where I could go to get this repaired?  Or does anyone know how I could go about doing it myself? I even bought another Uni mill on ebay. Unfortunately, that one got damaged in shipping and one corner of the box is broken, making it wobble. So I am still needing to know how to get it apart and back together if I replace the good parts into my good box.

I would really appreciate any suggestions anyone can give. I have lived with my mill for so long, I don't know what to do without it... all my nice wheat with no where to go, too.

Catherine

barryvabeach's picture
barryvabeach

Catherine,  sorry to hear about your problem.  I don't have a Marathon, but have fixed a few mills before.   According to a you tube video, , the stone closest to the front should move in and out when you turn the knob, the rear stone just rotates  https://www.youtube.com/watch?v=sXE_u__5X24    I assume you have tried to turn the knob to move the front stone to separate them- is the knob stuck, does it turn freely and yet the front stone doesn't move?  My guess is that the last time you used it, the grain had too much moisture, and has formed a glue of sorts to stick the stones together.  If you can get them apart, you can try to put some rice in there, with the stones set fairly far apart, to see if they will clean off the stones.  

sewcial's picture
sewcial

Your suggestions sound good, but the problem must be more than moist flour. When I began grinding, the stones tightened. I loosened them by turning the back stone by hand. Then they tightened again as soon as I turned on the motor. I attempted to adjust the fineness knob looser, but it just unscrewed from the bolt. I can put it back on or take it off, but it does not move the stone looser. It will attempt to make them tighter, but they are already as tight as they could possibly go. There is no way to grind rice or anything. I have tried rotating the back stone by hand using a rubber grip pad, but still nothing.

I was thinking of unbolting the motor to see if moving the rod between the motor and stones would help. Do you think that is wise? I don't want to make things worse.

barryvabeach's picture
barryvabeach

Catherine, the key is the fineness adjustment screw.  You need to get that to turn to fix the machine.  Either the knob has come loose on its own, or the screw itself is stuck. Can you take a photo of the end of the sides of the adjustment knob as well as the screw that it fits in to, that may tell me that the knob is just loose, and once we fix that it will work fine.    Another possibility is the screw is stuck. Is it possible that the screw got some moisture and was not turned for a while and has developed some rust?  If both of those issues are okay, I am not sure, but from the video, it looks like there are 4 guide posts that keep the front stone from twsting as it moves in and out. It is possible that one of those is frozen.  Can you take some photos of those guide posts?  It make take a few tries but we should be able to fix it, and it should cost more than a few dollars, but we have to confirm exactly what it causing the front stone to get stuck.  You can send me the photos by private message if you prefer.

Taking apart the motor assembly won't help.  The rear stone does not move front and back, and the reason it is stuck, most likely, is the pressure from the front stone.   

sewcial's picture
sewcial

I found a person who had fixed a similar stone mill for his wife and took my mill to him. It seems I was just being too timid and didn't tighten the knob far enough to get it to move the stone. I thought it was tightening the stones too much in trying to put the knob back on...no rust or anything, the adjustment knob had just come loose and when I tried screwing it back on, it didn't grab the threads that allowed the stone to move. It is working again. A bit hard to explain, but he didn't really have to do much to it. 

I am so glad to have it fixed. I love that mill and have been using it for so long, I'd be lost without it. I also think it is the best and nicest looking stone mill I've seen. Too bad the company stopped making them.

barryvabeach's picture
barryvabeach

Catherine,  glad you got it fixed.  Some of the old machines will last nearly forever.