1050 Re-Assembly Question

[samrebel]

Hello all, new to the forums and back into Atari 8-bits for the first time since I was a kid in the 80's.  I've acquired a 1050 from Goodwill with a WST mechanism.  I haven't yet been able to test it because my 800XL keyboard mylar is shot and I haven't had time to put the replacement in yet.  I did take the drive apart to clean and service it: the spindle motor was seized and required a lot of lubricant but it freed up and worked fine when I fed it 12V from my bench power supply.  There was corroded aluminum powder all over the circuit board but everything cleaned up ok, I cleaned and lubricated the rails and cleaned the heads, etc. 

 

The issue is that I can't seem to get the drive back together properly.  When I put the 4 posts in the standoffs on the case, and then try to lower the drive onto them, I can't get the drive far enough towards the rear of the case to align them without hitting the heat sink for the voltage regulators.  The drive was more or less together when I got it, but it did seem like the drive stuck out too far.  Has anyone else experienced this?  Could I have a drive case for a Tandon drive?  The front faceplate is the 3 finger kind, if it helps. 

 

Thanks for any help.

[+kheller2]

A picture would help.  But, did you align the motherboard properly and screw/tab lock it down in place?  The drive mech should sit just fine on the 4 metal stand-off pegs.  

[samrebel]

You can see in the attached pictures that the notches in the motherboard won't allow it to slide back any further. 

 

I did try to put some rubber feet on the bottom of the board to raise it up and replace the RF shielding box that I removed, which had rubber feet to standoff the board from the sheet metal. I thought that the taper that the posts have might let it slide back just enough, but no joy.I'm beginning to think that this drive didn't originally come in this case and the manufacturing tolerances are loose enough that these parts never fit together properly.

[Paul Westphal]

I have put them together by accident where they stick out a little further but they can usually be slid back to where they sit flush in the front : 

 

[Vyvyan B.]

Does it say Singapore or Hong Kong on the bottom label? All the 1050s I have with the WST mech have a black heatsink. That could just be coincidence so YMMV

[+kheller2]

That is the wrong mech for that motherboard/ROM, and also then probably the case.

 

Take a look at these pics here: 

 and pics here:

 

Having said that...  we've always wondered if the WST mech would properly work with Tandon ROMs and their stepper code (probably yes), the other way (WST ROM with Tandon Mech is questionable).   

It is also interesting that you have that pink ground wire which Tandon units don't have.  But you have a Tandon ROM and heat sink.... so this is a very interesting hybrid

What does the sticker on the bottom of the case say it is?

[Vyvyan B.]

Yea, that's a Singapore case and board with a Hong Kong mech in it. I looked at the ones I have and all the Hong Kong ones have a dark green board with a black heat sink.

[+kheller2]

BTW, it doesn't look like the board is set properly on the 4 screw pegs.  The front peg looks misaligned and the locking tab isn't over the board.   The back looks like it needs to sit down a bit more as well.  But, hard to tell with this combo going on.

[samrebel]

The case sticker says Singapore, so you're correct. Incidentally, before I read these responses, I removed the heat sink to test the fit without it, and the drive would sit on the posts correctly, but the post/rubber bumper on the underside of the cover now hits the gold anodized sheet metal portion on the top of the drive and prevents it from going on completely.  So I don't think there's any way for it to fit together correctly. 

 

Karl, you are correct, the board wasn't down far enough to snap in because of the bumpers I put on the underside. I took them off and it snapped down into place correctly.  It didn't help with the drive fit, unfortunately.

 

Any thoughts on whether I should try to get a Tandon drive to go in it?  Or go the other route and get a HK case for the WST drive? Or start over with another drive and use this for parts?

[Vyvyan B.]

Someone here probably has a a spare Tandon knocking about. I myself am on the lookout for a WST mech for parts to complete a unit I have that's missing it's mech. So if you find one and wish to sell the WST I'd be interested. Or, conversely if you want this HK case and board maybe we could work that too. Where are you located BTW?

Edited January 20, 2023 by Vyvyan B.

[samrebel]

I'm in Atlanta, Georgia, USA. I'd be hesitant to sell the WST mech for money because I can't verify that the spindle motor will maintain the proper RPM with a disk inserted and the head clamped down. It was in fairly rough shape when I got it; the spindle motor was completely seized and the drive chassis had a lot of that white aluminum corrosion on it.  I'd be willing to send it to you for the shipping cost, if I can get my hands on a Tandon drive. Let's see what turns up.

 

Sam

[_The Doctor__]

sounds like swap time.

[Vyvyan B.]

What's it going to cost to buy a working 1050? Send me the mech and I'll put it together. If it works, I'll send it back and we can work out a mutually agreeable term. I fix things. It's what I do.

[samrebel]

Vyvyan, DM me your address and I'll put it in the mail to you next week.

[Vyvyan B.]

PM'd

[+bf2k+]

From your pic above, the lower locking tab is not locked over the board indicating that the board is sitting up too high...