How to repair doser on a coffee grinder?
July 24, 2015 8:16 PM Subscribe
I recently obtained a used Anfim Best grinder for a great price, but the doser was not working and missing a few parts. I've bought the spare parts now and nearly have it back to working condition, but need some advice on the handle and gear mechanism which is causing me problems.
The replacement brass gear does not move smoothly inside the handle. So when I assemble everything and try to use the handle, the gear sticks in the handle. Then it either doesn't move the gear far enough for the return spring to drop into the gap of the gear teeth; or it get stuck and pushes the return spring out of the way. I suspect the inside of the handle is not a true circle, and may have been dropped or squashed out of true at some point in the past.
I'm not a mechanic or engineer so I may not be using the right terms for the parts - but here are some photos to help explain my problem. There's also this parts diagram.
I'm hoping some handypeople or coffee addicts here on Mefi might have some knowledge about these things and tell me
1) am I reassembling this properly?
2) am I on the right track by thinking that this gear should be moving freely inside the handle? and if so...
3) how do I make it happen - do I attack the gear with a file, or somehow try to expand the handle, or file the inside of it? I don't want to damage the doser in my ignorance.
The replacement brass gear does not move smoothly inside the handle. So when I assemble everything and try to use the handle, the gear sticks in the handle. Then it either doesn't move the gear far enough for the return spring to drop into the gap of the gear teeth; or it get stuck and pushes the return spring out of the way. I suspect the inside of the handle is not a true circle, and may have been dropped or squashed out of true at some point in the past.
I'm not a mechanic or engineer so I may not be using the right terms for the parts - but here are some photos to help explain my problem. There's also this parts diagram.
I'm hoping some handypeople or coffee addicts here on Mefi might have some knowledge about these things and tell me
1) am I reassembling this properly?
2) am I on the right track by thinking that this gear should be moving freely inside the handle? and if so...
3) how do I make it happen - do I attack the gear with a file, or somehow try to expand the handle, or file the inside of it? I don't want to damage the doser in my ignorance.
The shape of the lever doesn't match the one on the exploded diagram you linked. Are you sure you have the correct parts?
I would not go trying to reshape any of the parts. Defects in the parts themselves are a lot less likely than incorrect assembly or simply having the wrong parts to begin with.
posted by jon1270 at 3:34 AM on July 25, 2015 [1 favorite]
I would not go trying to reshape any of the parts. Defects in the parts themselves are a lot less likely than incorrect assembly or simply having the wrong parts to begin with.
posted by jon1270 at 3:34 AM on July 25, 2015 [1 favorite]
Response by poster: Thanks everyone.
As jon1270 remarked my lever is different from the diagram, but seems to be the same as in the photos markr linked to. In any case the lever was not one of the replacement parts, it came with the machine & I don't have any reason to suspect it's not the original. I have put this down to the diagram being from a more recent model - my grinder was manufactured in 2004 - and maybe they changed it slightly since then.
In the end I ended up going against jon1270's very good advice, and filed the outer points of the gear teeth slightly. I chose to attempt this on the gear even though I'm now confident it's the handle which is out of shape, because the chromed handle seems like it would be very difficult to work with compared to the brass gear. The gear is also cheaper to replace if I screw up.
I took off less than a millimetre from the gear diameter, but it's made a world of difference. The gear now turns smoothly and when I reassembled the doser it's working almost like a new one.
posted by joz at 11:49 PM on July 25, 2015 [1 favorite]
As jon1270 remarked my lever is different from the diagram, but seems to be the same as in the photos markr linked to. In any case the lever was not one of the replacement parts, it came with the machine & I don't have any reason to suspect it's not the original. I have put this down to the diagram being from a more recent model - my grinder was manufactured in 2004 - and maybe they changed it slightly since then.
In the end I ended up going against jon1270's very good advice, and filed the outer points of the gear teeth slightly. I chose to attempt this on the gear even though I'm now confident it's the handle which is out of shape, because the chromed handle seems like it would be very difficult to work with compared to the brass gear. The gear is also cheaper to replace if I screw up.
I took off less than a millimetre from the gear diameter, but it's made a world of difference. The gear now turns smoothly and when I reassembled the doser it's working almost like a new one.
posted by joz at 11:49 PM on July 25, 2015 [1 favorite]
This thread is closed to new comments.
posted by KirkpatrickMac at 11:54 PM on July 24, 2015