[Halvar▼]

Here are some photos of the "full size" 3278 beam spring board I was lucky to find last november, shortly after I first read about xwhatsit's controller here on DT. This keyboard is fully working over USB with the controller now. I guess it's about time to post some pictures.

I'm talking about this:

More here:

Spoiler:

I've already shown the beautiful black and white double shot key caps of the 3278 yesterday. This model doesn't have the red and blue caps or the operator control panel of the 3278 A2, but a purer, monocrome look. There is also no IBM logo or anything like that on the keyboard.

The metal parts on this board showed no corrosion like the ones on Monster-Toys' or my 3278 A2, but the protective plastic sheet had disintegrated much more. There was nothing to save here, crumbs of the foil were everywhere in this board, and I already saw the first of them when I opened the package that the keyboard was in:

crumble

So the first step was to undress the board.

switches

Obligatory switch tree nursery photo:

switches in rows

This is the solenoid that is used to rattle loudly with every keypress to give a more typewriter-like feel (I'm not going to use this becaus I have an older version of the controller. The current rev 4 supports this with a little extra controller):

solenoid

Date stamp in the case -- this is the only date I have because the sticker on the bottom side is lost.

date

First tests with xwhatsit's controller showed that the controller couldn't calibrate all the keys -- there seemed to be some problems with the capacitance of some of keys which were either way too high or too low. So I opened the inner case to have a look at the PCB and clean it:

baseplate

pcb with controller (1)

switches bottom (1)

pcb connector

After a cleaning of all the surfaces an the connector there were only few problems left when calibrating the controller. A firmware upgrade of the controller solved all these problem though. Thanks to xwhatsit, I now had a fully functional usb keyboard!

Only thing that was left was to put it all together again and find a solution for the replacement of the rubber foil.

[Halvar▼]

Replacement for the contamination shield:

You definitely get the best feel and sound off a beam spring board by just doing without any replacement for the contamination sheet. The original sheet seems to me like an afterthought, and a board feels much better without it.

The problem with that is: if you really have a liquid or dust/dirt on your board, which is hard to avoid with everyday use, they can easily contaminate the switches and render them unusable. So IMO if you plan to use the board regularly, some kind of replacement makes sense.

MORE:

Spoiler:

Parak posted a thread on GH about how he used some poly film to replace the contamination shield:

http://geekhack.org/index.php?topic=46134.0

I followed his approach -- first I tried a few different plastic bags, including some waste bags:

wastebag

This shows how the foil was laid out to leave enough spare between the switches:

wastebag2

It's a compromise: if you don't leave enough foil between the switches, there will be "crosstalk" between the caps -- if you press a key, all the caps in the neighborhood will lean over towards the pressed key, which also feels pretty bad. This even happens a little bit with the original contamination shield.

If you leave too much foil between the switches or the foil is too thick, you feel the plastic foil crumbling and hear it rustling with every keystroke.

In the end, what I used was very thin clear "self-adhesive" wrapping film like it's used to wrap around sandwiches etc ("Frischhaltefolie selbsthaftend"), and that worked pretty well. It's still not as good as leaving out everything, but it's a good compromise.

fresh

So everything works now and I'm very happy with xwhatsit's controller and how my keyboard turned out.

controller

keyboard

[Daniel Beardsmore▼]

Does yours have an intact contamination shield? This photo desperately needs replacing:

wiki/File:Bespr_3276.jpg

[Halvar▼]

That looks much better than mine, but I will have a look into the wiki later this week and see what pictures I can add there.

[bitemyweewee▼]

Great work! Now I want one.

[dorkvader▼]

That looks much better than mine, but I will have a look into the wiki later this week and see what pictures I can add there.

It almost looks like dedalus put the contamination shield on the switches before installing them in the plate. I wonder if perhaps that's the best method. My plate has lots of corrosion all over it (unlike the pristine plate in your photos, halvar) so once I get it sanded / painted, I think I'll give that a shot.

Thanks for the excellent photos!

[Halvar▼]

Yes, that might be the better approach. To take all the switches out of the plate seems a risky operation though given how brittle that plastic is -- I didn't dare to do that, but if your plate is in a state of corrosion where you have to disassemble that part anyway, it sounds like a good way.

[xwhatsit▼]

Oooh pretty Halvar. The black-on-white legends are so sharp. The Q and in particular the 3 with the neato punctuation (what is that? says the anglophone) is particularly gorgeous.

Here's my 3278 data entry keyboard (arrived today!), beautiful triple-shot white/black/blue keys. The legends are lovely—although not as good condition as yours, Halvar—the brown/grey keys on the 3727s and 5251s (my other two beamsprings) don't compare.

[Halvar▼]

Yes, it looks like it's a hand-drawn font (as opposed to a constructed one), something you don't see on technical equipment any more at all. There are some really nice glyphs in it, like the ampersand, the question mark or the hash. On the German layout, the ß is really well done, and I also like the §. § is a sign that marks sections in legal texts. It's derived from a double S ("section sign").

[andrewjoy▼]

The fonts are lovely you just done see nice fonts like that anymore! I find most key legends are too small. Apart from my Round 4 SPH they are "teh s**t".

One day i will get a beam spring and it will be a good day !

[nacho▼]

Nice work and nice keyboard. How is the typing, compared to model F, e.g. ?

[kuato▼]

xwhatsit, that split bar is wild and those blue legends are gorgeous!

Here are mine:

66 key:






75 key:



87 key:





cheat-sheet

[Halvar▼]

Now that's a collection!

APL symbols are so pretty, and APL is so elegant.

[Parak▼]

66 key:

Where did you even dig that one up from?!

and were there any others.. I mean I'd settle for just one more.

[kuato▼]

Where did you even dig that one up from?!

and were there any others.. I mean I'd settle for just one more.

A friend found it for me through an e-cycler. Sadly, this was the only one they had. I had never seen a 66 key until I saw this one.

[ShawnMeg▼]

Please upload a video so we can hear the sound.

[Hypersphere▼]

Replacement for the contamination shield:

P1000815 (Large).JPG

You definitely get the best feel and sound off a beam spring board by just doing without any replacement for the contamination sheet. The original sheet seems to me like an afterthought, and a board feels much better without it.

The problem with that is: if you really have a liquid or dust/dirt on your board, which is hard to avoid with everyday use, they can easily contaminate the switches and render them unusable. So IMO if you plan to use the board regularly, some kind of replacement makes sense.

MORE:

Spoiler:

Parak posted a thread on GH about how he used some poly film to replace the contamination shield:

http://geekhack.org/index.php?topic=46134.0

I followed his approach -- first I tried a few different plastic bags, including some waste bags:

P1000404 (Large).JPG

This shows how the foil was laid out to leave enough spare between the switches:

P1000427 (Large).JPG

It's a compromise: if you don't leave enough foil between the switches, there will be "crosstalk" between the caps -- if you press a key, all the caps in the neighborhood will lean over towards the pressed key, which also feels pretty bad. This even happens a little bit with the original contamination shield.

If you leave too much foil between the switches or the foil is too thick, you feel the plastic foil crumbling and hear it rustling with every keystroke.

In the end, what I used was very thin clear "self-adhesive" wrapping film like it's used to wrap around sandwiches etc ("Frischhaltefolie selbsthaftend"), and that worked pretty well. It's still not as good as leaving out everything, but it's a good compromise.

P1000428 (Large).JPG

So everything works now and I'm very happy with xwhatsit's controller and how my keyboard turned out.

P1000482 (Large).JPG

P1000471 (Large).JPG

It seems like a real art to get the plastic film installed just right. Do you think that a "roof" or keyboard cover could provide adequate protection for beam spring switches? Of course, this would only provide protection from dust when the keyboard was not in use, but it seems it might suffice if users do not have food or drink near the keyboard when it is in use. Thanks for your thoughts on this.

[daedalus▼]

That looks much better than mine, but I will have a look into the wiki later this week and see what pictures I can add there.

There were at least two types of contamination shield - the black rubber ones which seem to be quite common, and the clear (some kind of plastic, slightly rubbery, has yellowed with age but hasn't crumbled like the black contamination shields, not sure what it would be) material that was on my one, here's another picture, not great quality -



My theory is that the rubber came from the Canadian and US-made ones, and the clear stuff was from European made ones (which I believe were made in Italy, and possibly the UK too) but I don't have enough data points to confirm that. There do seem to be other variables, such as how some keyboards I've seen have blue switch housing, and others are black...

66 key:

Ah, the Data Entry 5251 keyboard, I think this is the first time I've seen one of these, very nice

[Muirium▼]

I'll try looking for that the next time I visit a local museum which has an Italian made great white Displaywriter keyboard in storage.

[Halvar▼]

There were at least two types of contamination shield - the black rubber ones which seem to be quite common, and the clear (some kind of plastic, slightly rubbery, has yellowed with age but hasn't crumbled like the black contamination shields, not sure what it would be) material that was on my one, here's another picture, not great quality -

My theory is that the rubber came from the Canadian and US-made ones, and the clear stuff was from European made ones (which I believe were made in Italy, and possibly the UK too) but I don't have enough data points to confirm that. There do seem to be other variables, such as how some keyboards I've seen have blue switch housing, and others are black...

Ah, I didn't know there were two types.

My two 3278s both have the blueish black crumbly kind. The compact 3278 A2 was made in Greenock in 1980, and of the one in the pictures above I don't know where it was made because the sticker on the base plate is lost.

[xwhatsit▼]

My new Canadian data-entry 3278 (picture above) has (had) the black crumbly crap, so there's another data point. My 3727 (Armonk) is the same. I can't remember both where my 5251 came from and what sort of shield it had.

The beamsprings all seem to still have that clear stuff in them, between the bottom plate and the pad card. It extends out of the sandwich to sit underneath the controller.

[Halvar▼]

The beamsprings all seem to still have that clear stuff in them, between the bottom plate and the pad card. It extends out of the sandwich to sit underneath the controller.

That mat is made of black rubber-like material on (both of) mine.

[xwhatsit▼]

What the! I'm glad they didn't change the controller pinout just for shits and giggles as well

[mr_a500▼]

My Canadian made 3278 had the "black crumbly crap"™.

I've noticed that there is also a difference in the colour of the plastic switch casing. The Canadian (and US) ones were black and some of the European ones (German? Irish?) were light blue. Why? Who knows? (who can understand the Irish or the Germans?)

[daedalus▼]

Irish?

Scottish. We made Alps, the Scots got IBM.

[Halvar▼]

@daedalus: thanks for uploading the IBM manual page about how to reattach the fly plate to a switch to the wiki! This was most helpful to me yesterday.

wiki/Beam_spring

[mr_a500▼]

Yes, indeed. Thanks daedalus. That manual saved my ass.
(...not literally.. my ass does not contain a beam spring mechanism)

[Muirium▼]

Phew. Because those are rare enough it might just be necessary to scavenge it…

[mr_a500▼]

Irish?

Scottish. We made Alps, the Scots got IBM.

Oh. Nobody understands the Scots.

[Muirium▼]

Very pleased to see this clip doing the rounds. Weegie Trek!