MP11SE fixing slip tape issues

KevinM

In just the last few weeks my MP11SE has deteriorated quite badly with slip tape issues. It has been problematic for a while but has got bad enough now that pieces in certain keys can't be practiced.

Since I've no idea when my Vidal is going to turn up (US export license and UK customs issues hell) it looks like I need to deal with my MP11SE now rather than wait for my new keyboard.

I've been watching a few videos. So far this one looks the most helpful of the bunch I've watched.

Other videos have replacing all the padding as well as the slip tape, while others are recommending using superglue to apply the slip tape to the padding. My reading up about superglue is that it does not work on teflon which is kind of not surprising. Teflon is made to be slippery.

So I think on the replacing of the slip tape I'm going to follow the instructions of the video above. Which just means buying the teflon.

I still have other choices to make though. Do I replace the teflon tape for all keys, a big job that will be all day and may be longer since my back may not able to deal with all the work at once. Or do I fix just the keys with known problems, or do I take all the keys out and examine and fix those which are broken now and ones which look like they could be a problem in the future.

Anyway, this is all very frustrating.

KevinM

This is my progress.

Almost done, just having a break to give my back a break.

WieWaldi

What are you doing now?
Only fixing the keys with the issues?
Or all of them?
And how many keys have you fixed already?
How long did it take to do so?

Anyway - good you started. Only god knows how long your Vidal takes to come.
(And in the worst case, you could find you like the MP11 more than the Vidal. Then it wouldn't be a worst case anymore.)

KevinM

I started by fixing the four really obvious problematic keys. The ones limiting my practice.

I then went through all the keys to find ones which could be a problem in the near future put stickers on them and there were about 20 of those.

From start to finish, ie including getting the old z frame out and moving the MP11SE onto it and then the reverse and cleanup. I would say 6 hours.

It all seems to work again but I am weary and my back is sore.

Tog

Having already completed the process myself a couple of times myself I now only fix the keys that are obviously problematic and any that I gauge look as though they're likely to fail shortly. This usually amounts to about half a dozen keys at a time and I can complete the whole process in a couple of hours. I purchased an inexpensive rechargeable battery powered screwdriver for £15 which speeds up the removal and replacement of the many base screws significantly. There are two distinct types of screw and I keep them stored separately in sandwich bags for convenience during the procedure. The only major gotcha is to be careful not to strain the computer style ribbon cables connecting the top and bottom halves of the instrument, they're simply a push fit into their respective sockets and will be familiar to anyone versed in constructing desktop computers. After all, they are really just computers with a specialist keyboard as their Human Input Device (HID)! Although less than ideal this is a relatively straightforward process and is similar to the regulation any acoustic piano action periodically requires.

The fundamental design issue is, as is illustrated by KevinM's photos, with the Teflon film coming loose from its foam substrate as the glue starts to fail and not with the foam pad working loose from the key-stick. Unsurprising, given that Teflon has the lowest friction coefficient of any man made material! This is further exacerbated by any slight sideways force imparted by the capstan screw from the hammer mechanism during its normal operation and seems to affect some keys more than others, probably related to their geometry and assembly tolerances, as you can see from the witness marks of the offset impact impression on the affected keys before the pads have been renewed.

This is a process that seems to be required once every couple of years so I keep a quantity of the replacement foam pad material in stock which I obtained from WD Greenhill & Co in Southend, Essex, UK. I am pleased to confirm that contrary to some recent reports they are still trading following the untimely passing of their founder, Nigel, last year and they're being operated by his surviving family members, Jack and Alex.

Best wishes,

Tog