ICL PERQ 2 T2 Micropolis 1303 spinning down.

[Mattis Lind]

Hi Chris,

Den lör 2 jan. 2021 kl 14:03 skrev Chris Zach via cctalk <
cctalk at classiccmp.org>:

> I am dealing with this a *lot* with all these disks from Bob's basement.
> The problems seem to be three categories:
>
> 1) Disk does not spin up at all. So far it's all been sticking motors,
> they don't have a lot of start up torque at all. For the first 4 disks
> (ST412, Quantum 30mb, and two ST506) I was able to remove the bottom
> board, turn the disks manually (clockwise) while applying power to spin
> them up. The motor will start to turn, then as you continue to spin it
> with your finger it will go faster as the oils distribute themselves.
>
> Note: I need to figure out how/if I can oil drive motor bearings without
> opening them or ruining the seal.
>
> 2) Stepper/coil motors are stuck. This is easier to deal with on the
> ST412,Quantum,ST506 drives as there is literally an arm on the side you
> can move. These can be oiled externally if needed.
>
> On the RD53, the heads were stuck internally, what I did was unlock the
> heads manually (open bottom panel and turn the locking cam) while
> tapping the drive on the side with the palm of my hand. This could work,
> but hit it too hard or sharp and you will crash the heads. Maybe I could
> use the rubber hammer.
>

Thanks, I will take the drive apart a bit and see if I can find something
that can be unlocked.


> 3) Controller board caught fire and exploded. Yes, this burned my rug
> with flying debris, it can happen. Have a fire extinguisher handy.
>
> I am thinking of building a small dust free space to open the tops of
> other drives. Not sure if this is an immediate death sentence, a lot of
> these drives have filters inside that could probably handle one or two
> openings worth of dust, but man that is an edge case. In the old days I
> built a tent over my RM03 disk and counted on its absolute air filter,
> but I don't think I can do that with RL02's as the fan for the absolute
> air is also the disk spindle motor....
>
> Then again the Diablo 44 is always running the fan but I haven't found a
> source of air filters for that yet (unlike the RL02).
>

Actually I am not counting on this drive to live forever. I just want to
make an image of it and then probably replace it with something more
reliable. Like an mfm emulator.

/Mattis

>

>
> Hm.
>
> CZ
>
>
>
> On 1/2/2021 3:59 AM, Mattis Lind via cctalk wrote:
> > I have a nice ICL PERQ 2 T2 that I am going to start working with now.
> >
> > First thing was to try to image the hard drive. It is a Micropolis 1303.
> It
> > spins up but when it reaches what I think the correct speed it
> immediately
> > spins down. Usually I think there would be a click and then the heads
> would
> > recalibrate. But there is no click and no head movement.
> >
> > I really would like to make an image of the drive.  What are your
> thoughts?
> > Are the heads sticking?
> > Some kind of solenoid that is not releasing the heads? Not properly up to
> > speed? (but it sounds like the speed is right)
> >
> > /Mattis
> >
>