deskthority

Here's a Blue Alps Model M clone that I bought from Hammelgammler. It is in pretty rough shape, but definitely worth the time and effort of restoration. The caps that were originally on it appear to be ABS and are pad printed. He included a partial set of PBT dysesub caps from another board that was missing some keys, so I used the PBT ones where possible.

The taller keys like the F and top numberrow do not depress smoothly because of the force applied being off center, so I replaced those with greens (which have a lot less wobble than blues do) and they fine that way.

I ended up keeping the alpha and number pad numbers blue, but changed everything else to green, with the exception of the spacebar which is yellow now. The blues are all from the original board, just cleaned to keep that heritage there

As you can see from the internal pics, there is a diode for each switch. There's also a jumper inside to switch from AT to XT which is kind of neat

Will eventually be retr0briting it this summer and post back with results.

Wow that looks really nice.

I really like those new caps. Are they from the same type of board? And what are you doing with the leftover blues?

I'm cool with taking them if you don't care

This one had quite a few blues that didn't work which I guess isn't surprising given the condition that it was in. The extras will be spares in case some more stop working

Yeah, the PBT caps were from the same type of board, but apparently a different revision that had better caps. The other example of these that I saw posted here seemed to have a PBT case instead of ABS so there must have been at least two variations.

Yeah like you said I notice some caps are still very yellow

Socketed controller... NKRO diodes and a perfect ANSI layout.

Honey, you didn't even HAVE to simulate a 1390131 to sell that, we'd buy it all day long.

Damn, looks like the logo on the badge is top-aligned on this one. That's one theory busted then xD . Nice board though .

No serial numbers or markings anywhere? Too bad. Yeah the badge...and what a hint of yellowing.

Do the stabilizers look weird to anyone else?

No, I've seen them on other Alps boards.

Very cool. When I first looked at the pictures, I thought someone took a Keytronic cloned keyboard from the 1980's and swapped the internal parts into an authentic IBM 1390131 front and rear case.

But looking at the way that the PCB controller is cutout and the integration of the SDL connector, it looks very interesting and unique.

Are there actual LEDs for the num lock, scroll lock, caps lock?

Too bad the key caps are in worn and poor shape, but the rest of the case and keyboard should clean up ok.

But that excessive yellowing of the case plastics seems weird for an original IBM model M. Hard to tell if it is oxidation or perhaps tobacco?

Definitely a unique find.

the human slime on the plate and the film over the PCB , my money is on tobacco for the most part.

I'm all for modifying boards but why did you change some of the switches?

Redmaus wrote: Do the stabilizers look weird to anyone else?

They are costar-style stabilizers and are found more often on Taiwanese boards that aren't Alps-manufactured. I've seen them on my NTC 6151N and I believe Chicony 5161s have them as well. They turn up every now and then, but they are not very common.

I find it pretty ironic that this model has NKRO whereas legit Model Ms did not.

Pretty sweet board. Have you tried using ultrasonic cleaner on the broken blues?

Blaise170 wrote: Pretty sweet board. Have you tried using ultrasonic cleaner on the broken blues?

Another good way to fix blues that might have worn out is just using contact plates from SKCM Orange, which are much much more common but also full-length like the SKCM blue switches. I've used them with no problem in the past, though that was with SKCM Amber.

I changed the ones that are further away from center because they bind up fairly easily because of how the long stems are and pressing the keys down is actually off center given the angle on the top of the cap, especially on the F row. Greens are smooth enough so that this isn't as much of an issue. I like smooth spacebars, so I ended up swapping that one to a yellow switch. I'll have to make a typing video here pretty soon after I get my retrobrite setup up and running. I did retrobrite the caps and they look a lot better, will have to do this to the case too

The yellowing on the case and caps is definitely from ABS plastic yellowing over the years, I am optimistic that I can make it look like new again with retrobrite, though I've heard that there can be issues with uneven whitening sometimes called "blooming." Fingers crossed that it goes well!

Retrobriting is pretty fascinating to me, I'll have to make a separate post with my setup. I've got some 365nm 3W LEDs on the way, and am trying a reptile light as well, that has more UV B. I feel there hasn't been much of a scientific experiment on different UV lights and solutions. I've also heard that plain OxiClean without hydrogen peroxide works too which is nice if you want to make a good sized bath of it to soak a case. I have heard of the thick paste method, but I feel there's a higher risk of blooming, but that's just speculation on my part. Figure I can save others some time in doing some experimenting and posting my results.

Will post pics when it's all complete

orihalcon wrote: I changed the ones that are further away from center because they bind up fairly easily because of how the long stems are and pressing the keys down is actually off center given the angle on the top of the cap, especially on the F row. Greens are smooth enough so that this isn't as much of an issue. I like smooth spacebars, so I ended up swapping that one to a yellow switch. I'll have to make a typing video here pretty soon after I get my retrobrite setup up and running. I did retrobrite the caps and they look a lot better, will have to do this to the case too

The yellowing on the case and caps is definitely from ABS plastic yellowing over the years, I am optimistic that I can make it look like new again with retrobrite, though I've heard that there can be issues with uneven whitening sometimes called "blooming." Fingers crossed that it goes well!

Retrobriting is pretty fascinating to me, I'll have to make a separate post with my setup. I've got some 365nm 3W LEDs on the way, and am trying a reptile light as well, that has more UV B. I feel there hasn't been much of a scientific experiment on different UV lights and solutions. I've also heard that plain OxiClean without hydrogen peroxide works too which is nice if you want to make a good sized bath of it to soak a case. I have heard of the thick paste method, but I feel there's a higher risk of blooming, but that's just speculation on my part. Figure I can save others some time in doing some experimenting and posting my results.

Will post pics when it's all complete

I just went for the full blown liquid H2O2 like 80% and poured it over the whole lot , we don't get the day star out much in northern England so i had to maximise what we have . I am looking forwards to your UV results ( go and science the shit out of it) , i think then i would just buy some of the hair bleaching cream as i am too lazy to make up the solution myself.

Don't forget to wear and apron, underpants and gloves you don't want to get H2O2 all over your junk/hands or all over your cloths, it stings like a bitch if you do.

Add some conc H2SO4 to additionally get rid of all the organic residues on your keyboard .

Would that not effect the plastic ?

But true it would clean off the human slime.

Most plastics are not affected by acids. That said, I wouldn't advise anyone to use piranha, especially if they're not a trained synthetic chemist xD .

I'm a physicist and I use piranha all the time! In the lab that is. I do agree with you though, Chrytos, if you don't know what you're doing, stay away from piranha!

Khers wrote: I'm a physicist and I use piranha all the time! In the lab that is. I do agree with you though, Chrytos, if you don't know what you're doing, stay away from piranha!

I didn't know physicists used organics, or labs for that matter .

Depends on the physicist, I guess...

So this is a real IBM board, not a frakenboard ?

IBM clone yeah

Alkhar wrote: So this is a real IBM board, not a frakenboard ?

F R A N K E N

Khers wrote: I'm a physicist and I use piranha all the time! In the lab that is. I do agree with you though, Chrytos, if you don't know what you're doing, stay away from piranha!

I would say thats good advice , getting H2SO4 on your junk would be even worse, not quite as bad as hot bacon fat but almost.

Cannot wait to see this bad boy fixed up.

andrewjoy wrote: Would that not effect the plastic ?

But true it would clean off the human slime.

A quick check of a chemical compatibility chart says that ABS is only slightly effected by sulfuric acid.