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Versalab M3 Grinder - Page 16

Postby lennoncs on Sun Oct 01, 2006 5:07 pm

I am curious as to the type of bearing used on the grinder, angular contact with preload or a deep groove type with minimal preload, etc.

anybody have a bearing number?

just curiosity getting the better of me


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Postby lauradearborn on Wed Oct 04, 2006 5:59 pm

We're sorry to read on this forum that Jim Schulman still has problems with his M3 Grinder. The last we heard, it was resolved back in July. The last we heard from Jim was this email - "The improvements you describe for the new version sound like they will do the trick. As I said, I find it an excellent cupping grinder, and would be loath to use anything else. I have no doubt that once the bugs are out, it will make its mark for that."

We cannot know if something goes wrong in the field unless we are told.

Customers - please call us if you have problems. Or questions. We are totally available.

There is no new Versalab Grinder in the works. We have made some refinements in the details of the existing design, all of which are retrofittable. In the case of the bearings, a change in shim thickness and procedure in installation was all that was necessary. To retrofit, however, requires essentially complete disassembly of the grinder - half a day's job.

The motor drive pulley has had a surface improvement in that it now has essentially tiny teeth that grip the belt very well indeed.

Customers have been notified of field fixes and those who needed it have been sent kits at no charge, including an improved adjustment knob and a change in the belt specs.

In the specific case of grinder adjustment slipping, it is simply that the adjustment lock knob needs proper adjustment. One customer had this problem on a factory installed knob, and it was fixed over the telephone. The field installation kits came with the information.

By the way, Versalab sets no restrictions on what beans are used with this Grinder, whether commercial roast, light roast, SO. . . In fact, the Grinder was designed specifically with cupping in mind.

As most of our customers know, we never let down a customer. We have always fixed any problems that have occurred over the many years we have been in business.

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Postby another_jim on Wed Oct 04, 2006 7:47 pm

I don't want to get into another "he said, she said" contest on this; but customer relations at Versalab seems to work this way. There are two issues here, the construction of the grinder and the quality of Versalab's service.

On the construction of the grinder. The same email Laura quotes had this as my final status report:

I'll reseal the unit with more loktite and see if it works at a looser setting.


It didn't. That was my third and last try; and I didn't email them again.

To be perfectly honest, everytime I opened up the pulley-wheel and axle assembly, I got angrier and angrier. I had paid $800 odd for a grinder designed so shoddily that the main transmission was held together by a simple bolt that had to be set just loose enough not to destroy the bearing, and still tight enough to transmit the grinding force. Let me explain this:
-- a slotted screw has a better transmission than this, it has a slot, and the screw driver pushes against it sideways;
-- imagine trying to twist open a screw which has a nickel sized flat head by pressing down on it with a screw driver that also has only a nickel sized flat end, using only the friction created by the downward pressure to generate the sideways torque;
-- now try grinding coffee with the same arrangement;
-- now be told that if you press down too hard, you'll damage the bearing underneath
-- that's how the pulley to axle arrangement works on the M3 grinder

I gave up on trying to "tune" this bad joke with loktite, and acetone, or whatever else they would come up with in the next iteration. I reset it so the bearings are overstressed, but so that nothing slips either. When the grinder stops working, I will throw it out. Life is too short not to cut ones losses.

On Versalab's service. Perhaps, I misunderstood the emails; and perhaps, if I had sent the grinder back they would have repaired it properly at no charge to me. However, for me, the time for that is past. Every problem with these grinders has been interpreted by Versalab as not resulting from their design screwups, but from us grinding beans that are too hard. If I sent the grinder in for free repair; I would be tacitly agreeing to this spin on reality. I don't do that.

On the overall experience: This is a great grinder in its basic design and in its materials. It performs very well when it does work. However, I have no confidence anymore that Versalab can do the detailed assembly engineering required to build what is essentially a powertool, something that has to stand up to high repeated stresses. This grinder is less able to do that than even the many ultra low cost home grinders I've used up over the years. Versalab would be better off licensing their design work to a company that can build such tools.
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Postby hperry on Thu Oct 05, 2006 12:21 pm

When you do decide to "throw it out" please consider throwing it this way - I'll pay shipping and a recycle fee to boot. :) A short trip to Versalab for the replacement bearing Laura mentions and I'll make one of several local users who have used and admired mine very happy.
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Postby rasqual on Sat Nov 04, 2006 4:47 am

Well, I'll post here, finally. Hi Jim.

For what it's worth, I'll put in a plug for my favorite machinist -- a friend who colaborated with me on the ring roaster. He does everything from model train transmissions (wet gearboxes, tiny gears he fabs) to rock crusher engine mods. CNC capable, an unbelievable welder . . . and now a roaster manufacturer. ;-)

If anyone wants some custom work done, he won't be cheap but the result will be worth it. Personally, I'm not even doing espresso yet (so I'll be very Mr. Humble in these parts), but the Versalab sure looks like a sweet design. However, I already have a couple mods I'd like to see.

No rush, though. I'll have to cycle a couple more kids out into the world before I can afford to take espresso as seriously as I'll want to. Not buying a Versalab will probably allow me to pay for another, what -- week of college? ;-D
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Postby digito on Tue Nov 28, 2006 2:38 am

Distance from the burr to the bearing and the belt caught my attention at first sight last year.
The machine does a great grinding job but the reliability worries me.
my thought to get a M3 is held up. finally Jim got the problem.

The leverage effect applies large torque on the bearing during grinding. If 100lb light-roasted beans can damage it, maybe 300-500lb dark-roasted beans will cause the same problem after 3-5yr of use. Another bearing near the burr may ease this problem. I might be wrong, but the durability of a commercial product is much important than its performance.

The idea of M3 is brilliant. If these small concerns are removed, it's definitely a killer.
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Postby rasqual on Tue Nov 28, 2006 3:16 am

A fairly simple design change would be to add a bearing above the pulley, rather than below the current bearing. Two spare belts could be pre-mounted around the shaft in an unobtrusive stowage, ready to drop in place as replacements, with no need for disassembly of the bearing.

When excellent things work, the results are excellent. When they don't . . .

Yah, don't chuck it, Jim. I'd beg it off you for use at the farmer's market -- though that's a long way for a potentially ideal espresso grinder to fall. ;-)
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Postby another_jim on Tue Nov 28, 2006 7:51 pm

So far the grinder is moaning, but hanging in. When it quits, I'll put it up as a prize for the DIYers here.
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Postby cannonfodder on Tue Nov 28, 2006 8:40 pm

Now that sound like a fun project.
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Postby Teme on Fri Jan 26, 2007 7:42 pm

What's the status on the M3s? Jim has experienced problems, how about others? The grinders are still going strong? No issues?

Br,
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