Bump Mod on 1977 Rhodes 73 Stage

[Sameyeam]

I'm doing some refurbishments on a 1977 Rhodes 73 stage piano. The felts are on the hammers (not the pedestals) and appear to be in good condition. I've seen videos online for the installation procedure but not with this particular unit. The pedestals are flat bare wood. I have my head around how to do this, but I'm wondering if this is a good idea on this particular unit. Will it improve the soft touch aspects etc? Thanks!

[sean]

Sam,

I believe that the general consensus is that it is best to remove the felts from the hammer cams, and install new felts on the key pedestals with the bumps.

Sean

[Sameyeam]

Thanks for that Sean. I'm not going to be that aggressive with this, mostly due to fear and inexperience So the question then is would the mod still work to some degree if I just glue the bumps on the pedestals, or would I be better off not doing the mod at all.

[pianotuner steveo]

You are better off with the mod if done correctly. You need to cover the bumps with felt to help hold them in place, and to reduce noise. The white felt on the hammers Should be removed- it loosens up easily with lighter fluid. (Naptha) Do not use anything super aggressive such as products containing acetone, it with either craze or downright melt the plastic.

[Sameyeam]

I appreciate that Steve. I may try the mod (leaving the felt on the hammers) and see what that does. If that doesn't work I figure I can always fall back on doing it the right way ;-) as you suggest. Thanks!

[sean]

Sam.  We were trying to save you from that foolishness.  Don't waste the effort with something you will have to tear out and fix later.

The miracle mod expert, Ben bjammerz Bove, has laid it out years ago:

I highly recommend removing the felts from the hammers, and reinstalling or putting new ones on the key pedestal.  The problem is you have to make sure the bump lines up perfectly with the curviture of the hammer.  if it's off slightly, you can either get the felt falling in front of the bump and making the keys lock up from playing, or if it's too far back the hammers come to rest much higher than they should, and stay slammed up against the tines and stop the notes dead.  I have seen this about 3 times so far with "just the bump" mods.  Will link this to the big thread later.  Trust me it'll save you time actually, if you have to redo the mod over again versus you just pull the felts first.

(from https://ep-forum.com/smf/index.php?topic=7214.msg36624#msg36624)


Also, read every word of this thread (all three pages), https://ep-forum.com/smf/index.php?topic=4666.0



Sean

[Sameyeam]

Thanks for looking out for me Sean. The thread you posted was very helpful, and I was surprised to find a more balanced discussion of this topic with at least 2 posters reporting success without removing the hammer felts. I did some experimentation yesterday and was comfortable that I could avoid the pitfalls you (Ben) noted in your post. In any case I went ahead with the "just the bumps" mod. More work to do still, but it all seems good. No locked up keys, or dead notes. Perhaps I dodged a bullet here, but I did want to report back. Really appreciate your help and insights in any case.

[pianotuner steveo]

The bumps may eventually fall off without the layer of felt on top.

[cinnanon]

I did the bump mod on mine as well (same model, same year). It's difficult removing the hammer cam felts but everything else is easy. An issue with your approach, though it seems it's the same, is that you still have a wood-on-felt situation which is what the bump mod is supposed to be getting rid of. You'll also see tiny indents in the hammer cam felt created by this "just-the-bump" condition over time which may completely negate the bump mod you just did, and it may  be even harder to play a note than it was before you had installed the bumps at all. I think if this method would have worked, Rhodes would have instituted many decades ago since it is far easier.

To each their own, but this method will definitely cause some head scratching down the road (maybe even yours too!).

[Man-U]

Hi everyone,

I own myself exactly the same model ('76 Rhodes Stage 73 with white felts on hammer cams) and I'd like to take the chance of this interesting post to ask for some more advice on the subject.

Well... the point is that I'm still hesitating for the bump mod since I've never had the chance to play a Rhodes with such a mod (in France there are not so many Rhodes on the market, and furthermore this mod is probably rare). I understand that most people here in the forum (and elsewhere) have recommended this famous mod in many posts, but... this doesn't tell me if I'll appreciate the mod myself. To put things clear, my ideal keyboard is the one of acoustic pianos (which remains my main instrument) and I agree that my Rhodes has a heavy/sluggish feeling which avoids velocity. But, I don't dislike the deepness of the touch, much better for me than almost any numeric piano. On the other hand, I also like the touch of my Korg SV1 (when using the Rhodes sound). So, my first question is certainly a bit silly : is there any sense to compare the touch of such a keyboard with the one of a 'modified' Rhodes ?

My second question has more to do with the topic itself : to convince myself, would it be relevant to perform first the bump mod without changing the location of the felts (as Sameyeam did), and if I appreciate the new feeling, to do the rest of the mod in a second time ? I mean : technically, has the mod to be done in the same way if one does/doesn't want to change the location of the felts ? I have in mind the position of the bumps.

Thank you very much in advance.

[cinnanon]

If you play them side by side (one modded, one original) you'll be convinced.

[Man-U]

Certainly, Cinnanon, this would be the obvious way to do. But, as I said, I don't have this possibility ! No modded Rhodes around me, unfortunately.

[pianotuner steveo]

Yes, the bumps make a big difference, but again, in the long run, it is far better to do them correctly the first time. I own an SV1, and can confirm, the the bump mod will make the Rhodes feel like somewhere between the SV1 and an acoustic piano. If done correctly, proper placement, and felt ON TOP of the bumps. I can not stress enough that the felt over the bumps helps them to stay in place.

Cinnanon's  point about the cam felt getting indented is a very valid point too.

A Rhodes will never feel JUST like an acoustic piano, but the bumps do help a LOT. (Proper placement is critical)

[pianotuner steveo]

Man-U... you can achieve this by properly modding a few keys on yours, and comparing those keys to unmodded keys....

[Man-U]

Oops, I've probably misunderstood Cinnannon's message : I thought he suggested me to compare between 2 different pianos, but, as pointed out by Steveo (thanks!), it was more the idea to compare between 2 different keys (or more). Sorry if I don't get all the subtleties of english language !

Just to make it clear : I am already totally convinced that the mod should be complete (hence by changing the felts' position)  for the very good reasons that have been given in this post and others. So I'll do it that way... if I'm convinced to do it.

Now, to decide if I go for the mod or not, I thought that one way of doing could be
- glue first only the bumps (at least on a few keys in the 3 sections of the keyboard, for instance), without changing anything to the felts, and try the piano
- if I like the mod, do it completely, I mean changing the felts position
- if I dislike it, just remove the bumps that were added

The main interest of not doing all the mod first is that I won't have to do the tedious part of the job (remove the original felts and glue new ones) before being able to form my opinion, and that it's more easily reversible if I don't like the mod (just removing the glued bumps). On the other hand, my idea is worthwhile only if the right position of the bumps does not depend on the fact that the felt is going to be on the pedestal or remain under the hammer : if on the contrary it depends on that (for instance because of the difference of thickness or friction or other parameters), then my suggestion is not relevant at all.

Thank you also for your other answer, Steveo, about the comparison between a modded Rhodes, a piano and a SV1. It's a +1 in favor of the mod.

[pianotuner steveo]

I have never heard of anyone not liking the mod...

[Man-U]

OK, this is quite a definitive argument ! Many thanks.

Now, I have to determine the best moment for doing this mod during the process of a quite important restoration, and I've just opened a new topic to get some help on this matter :
https://ep-forum.com/smf/index.php?topic=10247.0

[melveyr]

Just to chime in, I recently bought my first rhodes and it had bumps installed but also still had the felt on the hammers. The action was so heavy it felt like i was doing push ups playing chords. I took off the felt off the hammers tonight and now the action is SO light. I think the felt from the hammers can catch against the bump. It's a truly terrible combination.

[cinnanon]

That is good to hear actually, that's kinda what I thought would happen.

[Man-U]

Melveyr, thank you for sharing your experience. Very convincing.

[Fred]

As Cinnanon stated, the bump WILL eventually wear a groove into the hammer cam felt. This will inevitably cause a sticking sensation when keys are depressed - it is only a matter of how much time that takes to happen. The PROPER setup here is to have the smooth, polished surface (such as a properly cleaned hammer cam) glide across the felted surface. The original setup is far from optimal in terms of functionality, as nylon plastic can be made smoother than the wood used for the pedestal (reducing friction), and with a bump present, the aforementioned groove will develop in the original scenario. 

The felt on the hammer cams is thicker than the felt supplied with the Miracle Mod kit. The original cam felts' thickness (too thick) is another source of the vagueness one feels in a piano with cam felts. Due to this difference in thickness, the location of the bump on the pedestal will change depending upon which felt is used in conjunction with where the felt is placed. So, to set up a sample area without removing the cam felts could result in having to relocate those bumps should you decide to proceed with a proper setup. Also noteworthy, such a test area will feel different than the proper setup of bump-modded, felted pedestals with smooth cams. 

Level your keys first, and do the mod as recommended, or, leave the action setup as is if you are looking to avoid spending the time. Most of all, have fun, and good luck!

[pianotuner steveo]

Yes, as I said before, if you mod a few keys- modify them correctly the first time and compare to unmodded. This is not a step that would have to be redone if done properly the first time.

[Man-U]

Thanks to all persons who kindly gave their advices.

I've just started the mod on my Rhodes. Since I've had to dismantle the hammer combs in order to change the tips, I took advantage of the moment to remove the felts on the hammer cams.

Then I began the mod with preparing the two extremal keys, as recommended in Vintage Vibe's video.

I've taken photos of the result, with the 2 keys unpressed and depressed.

At this very point, I would appreciate if an experimented forumer could tell me if the job was well done? I mean the position of the bump, of course. If it's the case this would put my mind at ease for next step. And if not, it's better to know it now !

Also : as you can see, the bumps (if correctly placed) are very near the front edge, so it seemed to me it was necessary to add felt also a bit on the front face of the pedestal in order to be sure that the bump would be well covered. Was I right ? I'm a bit afraid of lacking felt at the end because of the extra needed.

Thanks in advance.

[pianotuner steveo]

It looks to me that the bumps are too far forward, but how do these keys feel now?

[Man-U]

The keys feel well... as far I as I'm able to say something about that (I've never touched a modified Rhodes before). I mean, it's clear that the modified keys are much more responsive since they travel less. I can easily feel that when hitting repeatedly very quickly the keys (e.g. hitting the key 4-5 times per second). The sound produced by the tine seems OK also. But, with only 2 modified keys for the moment, it's difficult to have a real impression of what it's going to be. I should add that since I've just changed the hammer tips, the escapement/strike line has to be set up again.

Steveo, can I ask you why do you think the bumps may be a little too far forward ? The hammers rest completely on the pedestals, but maybe not enough horizontally ?

I've taken another photo of each modified key, when depressed together with its adjacent unmodified key, also depressed : this shows that the two corresponding hammers are quite parallel, especially for the low couple E/F.

By the way, can this 'conservation of parallelism' of the hammers before/after the mod be a criterion to know if the mod was correctly done? Or would it be better to aim at parallelism between the hammer and the key itself ? (which is not the case for me, as can be seen on the photos)

[pianotuner steveo]

They may be in the correct spot, but with the felt over the front, that throws off the perspective. The felt looks a bit thick. Is that key bushing felt?

If they feel better, then maybe you should continue, but you may notice more or less of a difference with the lower keys

[Man-U]

Yes, actually the felt is referred to as 'High Quality English Key Bushing Cloth'. I've bought the mod kit here :
https://www.electrickeys.co.uk/collections/fender-rhodes-action-parts/products/fender-rhodes-miracle-mod-kit

Is that too thick to do the job normally ? Or does it mean that I have to take this thickness into account to place the bumps closer to the front edge ?

Edit : the felt in question is 1.6mm thick

Thanks !