Whats up with my model f xt? Two layers of foam?

[Rezene]

I bought this off of eBay for 60 bucks and shipping because I thought it was too good of a deal not to and I was in a spending mood. https://www.ebay.com/itm/Vintage-IBM-Mo ... 2749.l2649 It came in today and although the caps were really dirty, the cable is sticky, its missing feet and theres a slash in the f4 key the key feel is much smoother than the xt that I have already. (its my second mechanical and I already have two of them ) After opening it up I saw that there is no rust on any of the springs--my previous board had about 20% with rusty springs--and the barrel plate had much less corrosion. The foam also looks like there is two different layers of foam, that's not how its supposed to look right? The foam that I can see well looks to be new. Why would someone put new foam in a board onto of the old foam and sell it for less and untested? The label that it has also looks like an f122 label and not an xt label. It has some handwritten stuff as well. Does anyone know what any of it means

[Wazrach]

That's not new foam, you are just very lucky that the foam has kept well over the years. The stuff US Models F use seems to hold up much better than the white-skinned foam in all three UK Models F XT I have opened, which was completely disintegrated in each of them.

That is also not a second layer of foam, it's a strip of sticky sponge found at both sides of the assembly - this is there to prevent contamination.

The condition is fantastic by the way, nice find.

[Rezene]

That's not new foam, you are just very lucky that the foam has kept well over the years. The stuff US Models F use seems to hold up much better than the white-skinned foam in all three UK Models F XT I have opened, which was completely disintegrated in each of them.

That is also not a second layer of foam, it's a strip of sticky sponge found at both sides of the assembly - this is there to prevent contamination.

The condition is fantastic by the way, nice find.

It's honestly crazy how big of a difference in foam quality there can be between boards. In the other board I got the foam was gone to the point where the only thing left was the skin the foam sat on. This one looks so much different I honestly did not recognize the foam. I also did not see any of the sponge on my other board. I bought this board expecting nothing and I got a way cleaner board than the other one that I paid more for. The only things dirty are easily cleaned.

[Wazrach]

You got really lucky with that. I've seen a few examples of good foam, in fact, this new old stock IBM 5155 Model F XT has pristine foam in it. This has deliciously thick, yet slightly fuzzy legends btw. It also has a pleasant new old plastic smell which is fading the more I use it.

Enjoy your keyboard! Feel free to upload a typing demonstration if you ever feel like sharing it. Always love listening to Models F, especially since they all sound different. Unfortunately, my 5155 keyboard isn't very pingy: https://www.youtube.com/watch?v=2Is5ZxT2bss

[Rezene]

You got really lucky with that. I've seen a few examples of good foam, in fact, this new old stock IBM 5155 Model F XT has pristine foam in it. This has deliciously thick, yet slightly fuzzy legends btw. It also has a pleasant new old plastic smell which is fading the more I use it.

Enjoy your keyboard! Feel free to upload a typing demonstration if you ever feel like sharing it. Always love listening to Models F, especially since they all sound different. Unfortunately, my 5155 keyboard isn't very pingy: https://www.youtube.com/watch?v=2Is5ZxT2bss

I'll do a typing test when I get it back together. The caps and case are currently taking a bath. Considering I was 50/50 on it working ill take pristine foam

[Rezene]

I'm sure that atleast the top case was re painted. the thing for the feet wire is white. How do you know for sure that someone didn't put new foam in? is there some give away that it is original foam?

[User101]

I'm sure that atleast the top case was re painted. the thing for the feet wire is white. How do you know for sure that someone didn't put new foam in? is there some give away that it is original foam?

Check the one clip that hold the entire board together(at least that's what IBM did on my xt)if its surrounding is pristine then it is likely that the board was never opened. Just check the clip generally, if theres any sign of tempering.

[User101]

I'm sure that atleast the top case was re painted. the thing for the feet wire is white. How do you know for sure that someone didn't put new foam in? is there some give away that it is original foam?

Check the one clip that hold the entire board together(at least that's what IBM did on my xt)if its surrounding is pristine then it is likely that the board was never opened. Just check the clip generally, if theres any sign of tempering.

[Rezene]

There was a couple of small scratches on both sides of the clip it was maybe opened but i'm not sure. I made a typing test here https://www.youtube.com/watch?v=rQoBGNrdl2w it sounds very similar to my board that had no foam maybe a little more bassier.

[Fkazim]

What you have is replacement foam as the original foam covered the whole PCB controller but your foam is cut slightly short towards the top of the PCB as you can see from the exposed part of the PCB. Now it could be an IBM refurbished unit or could be changed by the old owner who knows but judging by the fact that the springs for the flip out feet are painted over I would say its been refurbished by the old owner or even a third party IT company.

Hope that helps.

[Wazrach]

What you have is replacement foam as the original foam covered the whole PCB controller but your foam is cut slightly short towards the top of the PCB as you can see from the exposed part of the PCB. Now it could be an IBM refurbished unit or could be changed by the old owner who knows.

Hope that helps.

That is 100% original foam. I've had 5 XTs with foam this good, so I know exactly what it looks like.

[AJM]

I'm sure that atleast the top case was re painted. the thing for the feet wire is white....

Well, it should be white. I have never seen one in grey, till now.

[fohat]

My theory is that XT and AT units were sold as consumer devices and so were kept dry inside conditioned houses, whereas the terminals were commercial/industrial and probably hauled off into dirty unheated warehouses after being taken out of commission..

[Wazrach]

My theory is that XT and AT units were sold as consumer devices and so were kept dry inside conditioned houses, whereas the terminals were commercial/industrial and probably hauled off into dirty unheated warehouses after being taken out of commission..

Considering my F122 smelled like a musty old aircraft hangar, I'd say that's probably true.

[Rezene]

I'm sure that atleast the top case was re painted. the thing for the feet wire is white....

Well, it should be white. I have never seen one in grey, till now.

That's weird. I figured they were are grey but with a sample size of one that probably wasn't very sound