HP-67 card reader Clutch BAD JOB

[Michel Beaulieu]

My card reader works great for some weeks after all your tips but i did a stupid thing : i oil the gearing for better pulling and less noise. It works greater for 2 days but after that, the clutch began to "slip". I open it thinking just cleaning the clutch but i saw the horror : The inner material of the clutch disentagrate with oil and the motor pin entering the clutch is now slack and no more traction is possible :-( I clean everything, the clutch is now empty of material and oil : what can i do replacing the material?

Hangry and desperately,
Michel :-(

[Vieira, Luiz C. (Brazil)]

Hi;

If I am in this same situation, I'd try to fill the clutch with some sort of material (I'd try some Epoxy-based, but people in here will give you other possibilities, for sure) tha I could drill latter, when dried. The problem is centering the hole and finding a driller with the specified diameter. This is what I woud do... What sort of material is the cluthc made of? Metal? If so, it's gonna be harmless. Anyway, try this "filling" material with another piece, let it dry, drill it and test if it fits fine in the motor axis then you can try the same procedure in the clutch.

Hope you have success.

Best regards.

Luiz C. Vieira - Brazil

[David Smith]

The "clutch" is apparently made of nylon. If it is completely gone, then your best bet is to find some nylon rod of the right size (try Small Parts, Inc). Cram it in the drive gear, cut it to length, chuck it up in a GOOD micro lathe or mill, and drill a new hole for the motor shaft. I had a friend who used to do this for me, but he sold his tools and moved.

If the clutch is somewhat intact you can try gluing it to the motor shaft. Clean the motor shaft well with alcohol to remove any oil. I then dip a resistor lead in a rubbery superglue called IC1000 (or is it IC2000) Tire Cement (Hobbytown has it). Wiggle the stuff around in the clutch hole, and stick it on the motor shaft. You don't want too much glue in the hole because it may prevent the gear from being inserted all the way onto the shaft. Also make sure you don't get glue into the motor bearings.

[Malcolm Brooks]

To Michel,

I disintegrated a clutch on the weekend :)

But I read on this site somewhere that you can use the insulation from wires of around the right size.

You will need to get wire with around 1mm id - and an oversize OD. You need an oversize OD since:-

A) it probably won't be centred and you can scrape it to make it centred.

B) the id will probably be a touch bigger than 1mm and making the OD oversize and stuffing it in helps shrink the id.

It helps to have lots of wire to choose from.

Mine works with just a touch of vibration. Maybe I'll have another go sometime.

Thanks Malcolm

[Michel Beaulieu]

I glued the clutch with the original material that was there. Now cards pass thru the reader too slow and i get "Error" message every attempt. Any ideas?

Thanks again!
Michel

[Malcolm Brooks]

To Michel,

If it did read ok a few days ago and you have not changed the wheel, and it reads slow now. Then it must be that when you replaced the clutch you glued it so the shaft is too long and it is jamming and running slow. Or when you screwed the motor back the clutch is jamming on the side and running slow.

I've had both.

When you screw the motor back make sure you can rotate the shaft easily, or test run the motor (disconnected from the circuit board)

If it is jamming on the side - slide a VERY thin piece of card between the clutch and the wall and then tighten the motor screws up.

If it is too long then I hope its not glued that well. It could be tears! Or you could try placing a thin bit of packing material between motor and frame to set the motor and shaft back a wee bit to give it clearance.

Thanks Malcolm