Topcat restorations



#12

I finally bought a 97 to restore for my collection. Do I need it? Of course not. Did I want one? Well, after I fixed a 92 for a guy a while back - that set the hook. After playing with it for a while, I had to have one.

Heh Norm, yeah, leds are cool, but BIG leds are even cooler!!!

Everything is now working but in trying to get some pencil marks off the bezel (previous owner numbered all the rows and columns) I've ended up with some shiny spots. I guess some are from wear as well. So here's the question:

Has anyone come up with a good way to restore the nice original matte finish of the keyboard area? I've thought of trying some photo dulling spray (it's acrylic I think) but did want to jump that way just yet.

Any success stories out there?


#13

I have worked on zillions of these machines and have never found a way to restore a worn keyboard background. You can sometimes improve them quite a bit by cleaing off as much dirt as possible with Windex. Armor All can also help... it is particularly good at removing white oxidation stains.


#14

IIRC, there is a "satin finish" style of Armor All. I doubt it will make much difference, but you might try it.

I used "regular" Armor All on my -97 -- every plastic piece, inside & out. I don't think it covered up any keyboard wear, but the whole thing ended up looking better, and I suspect the plastic will last longer after having drunk up some fresh petrochemicals . . .

I've evened up (and created) "studio finish" on guitars by using triple-ought or four-ought steel wool. But that sounds a bit harsh, and you wouldn't want to go NEAR any of the yellow lettering! (Not to mention, steel wool and electronics are, like, mortal enemies!)

There's an enamel finish intended for military modellers, called "Dullcote" (from Testor's, I think). There are also matte fixatives (for artists) that might work. You should first experiment with any of these on a junk Pioneer, as well as on a patch of the inside of the -97's faceplate.

I would, however, NOT use Armor All until I'd ruled out later use of something like Dullcote! (I suspect that enamel wouldn't adhere as well to an Armor All'd finish.)

But, I'm no expert -- perhaps a chemist will chime in?

#15

Randy,
maybe, you want to give this one a try: http://www.swannysmodels.com/TheCompleteFuture.html , especially the combination of flat paint and future.

cheers,
hans


#16

Hi,
I think that you could do OK just going to

Home Repot and getting "Varathane Spray Varnish"

and you'd probably go with the matte version.

It's available in gloss, semigloss, and matte.

Now, don't overrate my suggestion..... probably

eventually the varathane varnish would peel off.

It also might wear fairly quickly.

Nevertheless, it's in the ballpark of what you are

saying you want to do (eliminate worn shiny spots).

The real test is your own skill applying it.....

personally I could never do a good job with spray cans,

but I've seen other people who do perfect work.

What you could do, is use this item as a baseline

beginning (maybe buy a can, try it on something

unimportant like an HP-49G+ or an HP laptop)

then you could continue by visiting a hobby shop,

saying "i want something tougher than this, maybe an

epoxy enamel" etc etc


#17

How would one spray the keyboard bezel without messing up all the keys? And you thought it was bad when you painted a window shut...


#18

Well, you gotta take it apart before you spray it.

I mean, that's just the way it is. It's about

getting your steps into the right order. You'd have

to take away everything that you don't want the

spray material to go onto. That means take it

apart, and then some.


Like, if Detroit wanted to dip a car into a

pool of paint, which they do, they have to make

sure that it's just the basic metal shell.

They don't put in the car stereo and the

seats until AFTER the shell has been thru the

paint pool. You would not want to buy the car

if they assembled all the seats and the rug

and the radio into it, and THEN they dipped

it into the paint pool. Same with the calculator.


#19

yes, i agree. i was lucky with my 34C (2101 build): the keyboard faceplate (not the metallic one, but the grey plastic sheet version) went off with the help of a toothpick and caught no kinks or wrinkles, because the self-adhesive foil on the back side did no longer stick to the plastic sheet. however, it was a pain to remove all foil residues from the upper chassis half. (i am not going to do it this way again. i think, it is much easier and less risky to remove the circuit assembly and all buttons). however, the question remains: what clear varnish with a "silk" matt appearance will stand the continuous wear by fingerprints?
at the moment i am experimenting with a mixture of 50% "future" and 50% acrylic water based matt clear varnish. if that tests o.k., i'll be dropping you a note. so far, my knowledge is that *enamel* modelling paint (such as humbrol and the like) definitely does *not* withstand the fingerprints, but will get sticky and shiny after a short time of use (wear). it also is not scratch-resistant.

cheers, hans


#20

Just a thought. Has anyone tried a finish called Fabulon? It's a semi-gloss floor finish, which is way more durable than polyurethane (and it smells much worse too, but unlike urethane, it dries completely overnight).

PS. I haven't tried it for this, so I don't know if it would harm the existing finish.


#21

.

#22

Although you can remove the HP97 key tops from the keyboard, it is not recommended. You can probably get a lot of them off without breaking the little ball on the end of the key shaft, but I suspect that you can't get them all off intact.

Also there is a good chance that some of the little "hats" will not stay on once you re-install them... this can be fixed with a little IC2000 glue.


Possibly Related Threads...
Thread Author Replies Views Last Post
  Care and Feeding of Topcat NiCads Les Wright 16 1,907 06-01-2012, 06:01 PM
Last Post: LHH
  Topcat Battery Polarity Les Wright 2 668 05-30-2012, 07:23 PM
Last Post: Les Wright
  Topcat HP-97 with very dim LEDs Michael de Estrada 9 1,257 12-04-2009, 05:25 PM
Last Post: Michael de Estrada
  My new traction system for Topcat printers. Ignazio Cara (Italy) 3 659 05-06-2009, 12:09 PM
Last Post: Geoff Quickfall
  Is there any interest out there in Topcat tear-bars? Ignazio Cara (Italy) 0 393 04-10-2008, 06:52 AM
Last Post: Ignazio Cara (Italy)
  HP 55 and HP 45 restorations Geoff Quickfall 4 720 01-18-2008, 11:52 PM
Last Post: Fred Lusk
  Topcat: country of manufacture Renato 17 1,711 05-05-2003, 11:52 AM
Last Post: Alex

Forum Jump: