In cleaning a used Fiorenzato T-80 grinder, I snapped the hex cap screw that attaches the lower burr assembly to the motor. I have tried 7 mm, 8 mm and 5/16 screws as replacements, and none seems to fit. The parts diagrams I have seen don't address the part, so I haven't been able to find any specifications. Any guidance would be greatly appreciated.

Thanks!

p.s. I'll post this question at coffeegeek.com as well (link).

Hi,

Since it's made in Italy, the threads are almost certainly metric.
I looked at a thread chart from the UK and I see that there are two different thread pitches for 7mm, and three different pitches for 8mm. So it's very possible that the 7mm or 8mm screws that you tried are the correct size, but the wrong pitch.
Do you have the old screw to test against a thread pitch gauge?

Fergus.

I have one of those grinders. I was able to clean it up w/out removing the lower carrier and am loathe to do so for fear of doing the same thing that happened to you.

Have you asked espressoparts.com ? They (barely) show the screw in this schematic.

http://www.espressoparts.com/category/03.03.fiorenzato/

They have been pretty helpful to me w/a few things. Just use the contact form on the web site. They seem to get to those pretty quickly.

I've had my burr carrier off of my T80 several times...most likely the reason it snapped off is that they are left hand thread (as the motor turns clockwise this keeps the bolt from coming loose). I believe that it is an 8mm with a fine pitch like 1.0, but I would have to remove mine to see. At any rate you will need the exact bolt, I would try cafe parts, that is where I bought many of my T80 parts.

Thanks for your suggestions. You are indeed correct that it's a left-hand bolt. That explains how I came to snap it off I managed to find a diagram indicating that it's 8mm X 16 bolt, but it didn't guide me as to where to find one. No domestic fastener companies seem to carry one. Espressoparts is yet to respond to my inquiry, and other companies that carry the grinders have been no more helpful. At this point, I suspect that my best hope is to track down a European supplier and special order it. What a lesson in avoiding hasty maintenance actions!

The T80's are produced by Quamar now.

Did you try Rudy at Cafe Parts here?

after extracting it you should be able to measure it
I don't have one in hand to help you but sure there are still a lot of t-80 around especially here in Oregon

Here is a source for left-hand threaded bolts: http://www.mcmaster.com/#cap-screws/=34s3j4

I realize it is not "right" but 5/16 (7.94 mm) is pretty close to 8 mm and the key will be the pitch of that 8 mm screw. A 5/16" bolt comes in two thread pitches - 18 tpi and 24 tpi (threads per inch).

A typical pitch for an M8 thread is 1.25 mm which equates to about 20.3 tpi.