Do you need to keep grinding guard on when using a cup wire wheel on the grinder?

It sounds like there may be an issue with the grinder's programming or calibration. Here are a few steps you can try to resolve the issue:

1. Check the grind settings: Make sure the grind setting is not set too low, as this can cause the grinder to continue grinding even after the brewing process has started. You may need to adjust the grind setting to a coarser level.
2. Clean the machine: If the grinder is clogged with old coffee grounds, it may continue to grind to compensate for the lack of coffee being produced. Clean the machine thoroughly, including the grinder, and try again.
3. Reset the machine: Turn off the machine and unplug it for a few minutes, then plug it back in and turn it on again. This can sometimes reset the machine and resolve any software or programming issues.
4. Contact Jura customer service: If none of the above steps work, it may be necessary to contact Jura customer service for further assistance or to schedule a repair.

I hope this helps!

A wire wheel is bought from the same sort of supplier as you would buy a grinding wheel.

The dimensions of the wire wheel should be similar to the grinding wheel it replaces, though the centre hole is usually larger and should be fitted and mounted with the correct size plastic bushes and steel retaining washers.

The guard and the tool rest should not be used with a wire wheel for safety and of course there should be a hook nearby to hang a pair of safety goggles...

Bear in mind, in a commercial environment, local legislation could exist that means only a suitably qualified and registered person is allowed to maintain/adjust a grinder as in the UK and Europe.

I have used a double-ended bench grinder for years with only a single wire brush, without problems.

Jet 577102 is a bench grinder with 1HP motor. It has got guards on the grinding wheel. Dust vents and guard makes the grinder makes it an efficient grinder. 115 Volt is needed to run this high performance grinder.

there is a nut and bolt that holds the little shelf below the grinding wheel. Loosen it and adjust the shelf or rest to within approximate ly1/8 inch of wheel for safety.

Unplug the grinder. Remove the guard on the side you want to change. Grasp the wheel with one hand while you turn the nut with a wrench. Remove the nut and arbor washer from the arbor shaft, pull the wheel from the shaft and replace it with a new wheel - DO NOT remove the paper label! Put the arbor washer and nut back on, spin the nut down snug, grasp the new wheel with one hand while you tighten the nut with a wrench. DO NOT overtighten the nut.

It may help to grasp the SECOND wheel (which should still be tight) with one hand while you tighten the nut on the new wheel. It may also help to loosen & tighten & adjust the new wheel several times until it runs as straight as possible before you really tighten it.

After tightening down the nut, dress the wheel with a wheel dresser to get it to run as balanced as possible and give you a smooth round wheel so your workpieces don't bounce against the wheel and so it cuts freely. Repeat as necessary to keep the wheel cutting freely, and to keep the grinding surface flat.

Your grinder is probably blocked.
It may happen if your coffee is greasy or oily.

Try to empty the coffee bin and using your vacuum cleaner, removed has much as possible the grounded coffee around the grinder.

Also, from the inside, look where the coffee grind should drop from the grinder to the brewer unit and removed any grind that could block and prevent coffee to drop.

The top guard should be set at 6mm and the bottom guard should be 2-3mm from the grinding wheel.
hope this helps,

All abrasives are marked with a maximum speed rating. Always check the rated speed of the tool you are mountin the abrasive on and be sure the rated speed on the wheel is equal to or higher than the rated speed of the tool. Never remove a guard to mount a larger wheel on a grinder than it is rated, even if the speed rating is ok!

Goggles or safety glasses need to be worn to protect the operator's eyes from the sparks and metal filings that result. Depending on the workpiece and time of exposure, hearing protection may also be required, the dust produced is also potentially hazardous. The toolrest (or workrest) should be mounted slightly below the center of the grinding wheel with less than 3 mm clearance from the wheel. This prevents the work from jamming between the toolrest and the wheel. Grinding wheels designed for steel should not be used for grinding softer metals, like aluminium. The soft metal gets lodged in the pores of the wheel and expand with the heat of grinding. This can dislodge pieces of the grinding wheel. Wire brushes require particular attention for the safety of the operator and bystanders as the metal wires may become dangerous projectiles as they could bind with the object being brushed and so throw it away with great energy. The machine needs to be securely mounted to a pillar or a bench to be used safely and effectively, often with an emergency stop switch or pedal fitted close by the machine, for use in emergencies.