700 disassembly questions

[devoid2]

Hi all,
Newbie here, first post. I've searched a bit here but thought I might just take the chance and ask about what might be common knowledge. My new project, the 700, needs a complete damper job and a few reeds. It appears to me that the damper assembly can't be removed without first removing the reed harp. There are 2 big screws which are pretty inaccessible with the harp in the way. Is this correct, or am I missing something obviously easy? Those two big slotted screws are going to need a serious sized screwdriver....

I'd appreciate any and all advice with this project. I've already read that this model is among the least fun to work on. Well, I'm committed now.

Thanks
D'2

[pianotuner steveo]

Why do you want to remove the damper assembly? This is not necessary in order to replace the damper felts, and is not recommended for beginners to do. It is very easy to snap the stickers (long thin wooden part on the back side that connects the damper arms to the action)

All you need to do is scrape off the old dampers, and glue on the new ones, the spring in the damper arm will hold it against the reed and act as a clamp until the glue dries. For best results, remove every other damper felt first and use the remaining old dampers as a guide as to where to place the new felts.. then remove the remaining old dampers after the glue dries on the new dampers.

Again, there is NO NEED to disassemble it further in order to replace the damper felts. Big can of worms.

[pianotuner steveo]

Be careful when turning the wooden screws to adjust the dampers. They are easy to break.

[devoid2]

Hi pianotuner steveo,

Thanks for the speedy reply and that advice, which makes perfect sense and will be followed precisely. Those big screws were scaring me! Will the reed harp need to come out for the reed replacements and their tuning?

d'2

[pianotuner steveo]

No, you do not need to remove the harp to replace reeds. Tuning them is another issue. The solder is pointing down on all reeds in a 700. Remember, there is about 150vdc going to the reed bar, always unplug before doing anything with the reed bar.

You can prop up a damper to remove the corresponding reed. Just be careful not to snap the damper arm off.

[DocWurly]

Steveo, this is a 700, and you seem to be giving some advice appropriate to a 1960's model.

The screws that affect the dampers on these aren't at the back, aren't metal, aren't in rubber grommets.  They are wooden, and are underneath the arms, in a mechanism that is pushing them up.  If they are adjusted wrong, they will mess up the whole action.

I agree that you don't need to remove the arms to replace the damper pads.

To replace reeds on a 700, you must either remove the harp or the dampers. You CANNOT lift these dampers to deal with the reeds.  There is not enough clearance.  Dealing with the reeds on these is a royal pain.  I do know people who tune them by removing them from the harp. Personally, what I do:

1. I number every damper with a pencil.  This is important because they are NOT all the same.  In some early instruments (at least on the earlier 120's), the bass dampers have a heavier spring and certainly the pads are oriented differently.

2. I have a special long super-skinny flathead screwdriver.  I use it to remove ALL of the dampers.  It's very hard to access just one or two dampers.  I suppose I would do so if I were just fixing one reed.  But be aware, putting the dampers BACK on is hard because of that wooden screw that goes through the middle of them.

I don't have a 120, 112A or 700 for reference, so this is from memory.  Caveat Emptor.

[pianotuner steveo]

Yes, I apologize. The action is the same as a 120. I was thinking of the later actions. I have a 700 but it is in my attic and I haven't used it or been inside of it in a long time. My bad.
My 700 was my first Wurlitzer. I distinctly remember replacing a reed or two without removing either the dampers or the harp, but in the long run it is easier to do so by removing the harp. The reason why I remember changing reeds without disassembly is because I got my 700 when I was a teen- before I studied or practiced piano technology. I didn't have the resources available to even know how to disassemble it that much. This is back when you could buy a brand new reed in a music store for $2!
When removing the harp in a 700 be sure not to lose any of the rubber insulator washers, they prevent the harp mounting screws from shorting out the reed bar D.C. Voltage. Also press the sustain pedal to raise the dampers when sliding the harp out.

[devoid2]

thanks all--just back now from a few days away. The parts should be at the post office tomorrow, so open harp surgery may happen in the next day or two. I'm going to take a few more long looks at the situation before proceeding. The capstain tool should be there too.

ciao for now

[pianotuner steveo]

Capstan tool? The 700 requires a different tool sold on eBay for adjusting letoff. (For people who live in the USA- seller doesn't ship overseas)  The capstan tool won't do anything that needle nose pliers can't do on a 700. I hope you didn't buy the long,flat silver tool.

[DocWurly]

You need BOTH the capstan tool (for hammer leveling) and the unique letoff tool for the 700.

I can't imagine trying to do the job of the capstan tool with needlenose pliers.  I mean, I suppose you CAN, but why make it more arduous than necessary? 

[devoid2]

The ebay capstain tool works great, and I already have a letoff tool for my regular piano regulation which fits and works. I found, after many trips to the back of the piano, that removing the key and making the capstain adjustment from the keyboard side is more efficient for me, even if it requires a few tries.

Update: I've numbered and removed all the damper levers and put them in a box for another day. I took the harp out to get a good look at it and do some tuning. I have a contact mic and a Peterson strobe, a light thumb-nail pluck of the reed seems to generate a clear enough tone for the tuner. I've also set the hammer heights and the action is looking a lot more organized. Not out of the woods yet, though. Two reeds are making that big, loud, bad sound which indicates to me that they're touching somehow. The feeler gauge says there's room on both sides, but that's not what my ears are telling me. I've cleaned up the point of contact over at the screw, and checked closely for obvious debris making trouble. At this point I'm suspecting the very tip, even though I can see light through the gap when it's stationary. I'm going to substitute a reed a few notes away toward the treble side to see if that's noisy too. Whoever tuned this instrument last didn't read the part about "pyramid shape" in the tuning leads. Wow, some interesting work. At least the harp hasn't been modified.

Once the harp is behaving and is acceptably in tune I'll then consider bringing the dampers back into the mix. Oh yeah, I need to set the let-off too--right now only one hammer is blocked against its reed.

In all, it's not going badly. It's slow work, but I guess that's the safest approach. Your input has been and is always appreciated.

cheers

d'2

[pianotuner steveo]

Paleophone, it is no more work to use needle nose pliers on the key capstans since it is easier (faster) to take the keys out anyway in order to speed up the process. That long flat silver capstan tool that some people sell is junk. It will work better if you bend it and grind the sides of the rounded part, but it is soft metal and gets chewed up after a while. I had one of those and think I threw it out.

[DocWurly]

Pyramid shape is the ideal, and when filing a reed you are trying to get a reed evermore like that shape.  But unless you intend to make your EP a personal religion, it's crazymaking and unnecessary extra work to make every reed tip a pyramid shape, unless it is giving you trouble.

Trying de-burring your trouble reeds with 600 grit sandpaper.  There may be a microscopic burr there.

Be aware that the hammer strike will affect the motion of the reed and possibly even its pitch, so you will still need to check the pitches after reinstallation.  Sounds like you have found a good method, though!

Bass reeds can be 3 cents flatter on average than the others--the strong overtones of those reeds tend to be 3 cents sharp, and that's what our ears tend to hear as the "correct" pitch on those.

[DocWurly]

Paleophone, it is no more work to use needle nose pliers on the key capstans since it is easier (faster) to take the keys out anyway in order to speed up the process. That long flat silver capstan tool that some people sell is junk. It will work better if you bend it and grind the sides of the rounded part, but it is soft metal and gets chewed up after a while. I had one of those and think I threw it out.

It's true, at times I twist key capstans on those models (120 through 140B etc) by hand.  Sometimes I keep the keys in in place and use the tool.  Depends.  Whatever works for ya.  But you NEED that sort of tool to adjust all captstans on the 200's and beyond.... So what did you use to adjust those if you tossed the tool???  Maybe you just mean you used a better version??

[pianotuner steveo]

That silver tool does not work well on the 140-200-720 actions. It's  too long,too wide, and not angled.
The one on eBay is far superior. It is a harder metal, the angle is very good, and it costs less (I think) than the long, flat silver one. It also fits in between the letoff (jack) capstans on those later models better than the silver one does- it's a little narrower. 

[devoid2]

Hi all,

The project continues. Tuning is pretty good (within 5 cents) although I have at least one reed which is kind of buzzy no matter how it's placed, even in a lower slot. I'm buying a replacement. The damper job has started and is progressing nicely. The old foamy things are pretty stubborn to scrape off.

There's a brass strip in and around the treble sustain block which I'm curious about--pic attached. Any ideas what it is? I was able to remove and replace that block without incident. Having the harp off and action open gave me a chance to Protek lube everything down there, and the damper mechanisms are getting lubed as they go back in. Oh yeah, I did remove all the keys to clean up crud from 1960. Broken reeds, a guitar pick, hair and dirt--no money. Shined up the capstains, cleaned up the balance and front rail pins. There was a missing fly stop cloth (felt) which made one hammer block the reed. Made a substitute from a piece of tuning felt strip.

Last question for now--I'm wanting to hear tremolo but don't want to buy a tremolo amp. Is there a mod for this amp anyone knows about?

thanks all

d'2

[DocWurly]

That brass or copper strip is important.  It's supposed to go on top of the reed screw heads, under the sustain brick's lower bar.  It closes up any gaps and helps the sustain brick do its job.  You may even want to get some more material kinda like that.

[devoid2]

Hi Paleo

The brass strip is present underneath the sustain block--I'm curious what the remainder of it it supposed to be doing. As you can see in the pic a lot of it sits on top of the sustain block. There are tiny pieces of a band-aid on it I guess to act as an adhesive. I don't imagine this was Wurlitzer factory protocol...? Could you explain a bit more about this brass strip? Is it on later models as well?

An interesting design feature--there are damper mechanisms for the last ten or so notes even though there are no dampers. I guess it has to do with how the action feels with the sustain pedal on or off.

thanks for all your help, and very glad I'm not doing this totally on my own

d'2

[pianotuner steveo]

I don't know what the exact use of that brass strip was, but it was originally underneath that big sustain block on the treble end. Looks like someone took it out and didn't know where it went...

I know of no tremolo/ vibrato mod for this amp. I would use an external rather than modify...

[devoid2]

Thanks guys,

The damper replacement is going very slowly. The "damper lever lift dowels" are proving to be problematic. There are more than a few split already by past adjusters--I'm thinking about re-manufacturing some of them out of dowels. I'm switching out some of them from the top octave where they really serve no purpose other than to make the action feel consistent. 3D printing could probably do a great job in fabricating them. Wish I had easy access to that sort of thing. It's really nice when they work--the damper-ing sound is a big part of the Wurli vibe.

So, I'm rebuilding the instrument note by note, and taking a step backwards here and there to correct tuning issues. Dampers are a lot easier to work on from left to right with nothing in the way on the right side of the damper. Removing and replacing a damper in the middle of a bunch is not pleasant.

Got a replacement reed for my buzzy F today. I'll need to grind it down to correct length; Dremel to the rescue. Hope it sounds mellower than what was there before.

Still, I got as chance to jam out a bit on the lowest 25 notes today and it was very satisfying. I guess I need to go on record as saying this process is slow and painstaking. Today's little jam session suggests that it's worth the trouble.

stay tuned--oh yeah, I put all new tubes in yesterday. No difference in the sound, but at least we're good tube-wise for awhile.

cheers and thanks for your guidance

d'2

[DocWurly]

Why would you need to dremel a replacement reed?  Is it the wrong style reed?  120's and 700's use a different reed than earlier or later models.

Here's a little article I wrote about reed compatibility.  Make sure you aren't putting this reed into a pickup in which it can't fit.

https://docwurly.com/wurlitzer-ep-history/wurlitzer-ep-reed-compatibility-history/

Some retailers (I know of two that do this) might send you a bass reed designed for a 1962-3 model 140, assuming they are compatible with 120's and 700's.  They are NOT and they won't work.  They have an entirely different taper and they will hit the hammers wrong.

[pianotuner steveo]

Splitting the wooden lift dowels is very common. Wood glue makes it stronger, it would be far easier to get some wood glue in there with a toothpick or something else, rather than try to make new ones and replace them. Good wood glue like titebond.

[devoid2]

 Why Dremel a reed? I'm not certain what number it was, but the reed I needed was not available a Vintage Vibe. The next lower note was available. That reed was about 1/32 longer than the reed it was replacing and needed to be made shorter. The Dremel ground it beautifully and easily. The reed sounds fine.

Those wooden lift dowels...I'm being really careful with them. One or two are split and missing much of the upper slotted section, so there's nothing there for me to fix with glue. They can be manipulated and I'll figure something out. For a real classy restoration job, I'd prefer to have the parts intact or re-made. I guess that's for the next owner to tackle...unless I find a 700 being parted out somewhere.

I'm up to key 38 on the damper job, and the treble dampers are coming up soon. Stay tuned.

thanks

d'2

[pianotuner steveo]

Reeds should never be sanded or dremeled- it can weaken the metal and cause it to break sooner rather than later. You would have been better off using the next higher reed and removing less solder.

[DocWurly]

Why Dremel a reed? I'm not certain what number it was, but the reed I needed was not available a Vintage Vibe. The next lower note was available. That reed was about 1/32 longer than the reed it was replacing and needed to be made shorter. The Dremel ground it beautifully and easily. The reed sounds fine.

Good reason!  As long as it isn't bridging one of the 3 transition points between the four reed shapes, that'll work fine.  On a 700 (as on a 120):

Can't use a 20-E3 (or lower) in a 21-F3 (or higher).
Can't use a 42-D5 (or lower) in a 43-D#5 (or higher).
Can't use a 50-A#5 (or lower) in a 51-B5 (or higher).

This is also true of the 1st year 140/145/720's (with no A or B at the end), with one addition:

Can't use a 14-A#2 (or lower) in a 15-B2 (or higher).

[devoid2]

Hi Steveo

The dremel was used to slightly decrease the length of the replacement reed, like by 1/32 in. It really seems to be working fine now.

In all the on/off cycles and countless reed adjustments, it now seems to me that the amplifier is not as loud as it had been. I've replaced all the tubes and I'm wondering if there is a point in the audio chain that might need some attention. I guess some kind of partial short might be within the realm of possibilities.

What a project....set the reed so it doesn't short out or buzz, check its tuning. Tune as needed, repeat, repeat, repeat... Check with the piano amp on just to be sure all is well. Then re-install the damper and check if the damper really damps. Troubleshoot if it doesn't.

And, a couple of reeds are noticeably softer in volume. Maybe I can live with that and just play those notes louder. Unfortunately, probably not.

d'2

[DocWurly]

unless I find a 700 being parted out somewhere.

A parted 120 will do.

[pianotuner steveo]

As long as the dremel is only used on the very end of the reed, I guess that won't weaken it.

[devoid2]

The damper job continues, slowly. I'm in the treble range now, but it's going to be on hold for a week--vacation.
There are two Allen bolts holding down the left end of the plate that the sustain block is mounted on. There are maybe five holes where bolts could go, and I'm thinking of adding another one or two. The sustain of some treble notes was improved by putting in a bolt nearby those reeds. Matching the size and thread shouldn't be hard, although I doubt I'll find Allen head bolts to match.

One note is playing softly, and it appears that reed is too short. It probably will get replaced unless there is some slack available in the front to back adjustment. I have to go back and retune some spots which aren't sounding so great, and that's going to be yet more struggles with the dampers. Whatever...the overall, vibe is getting progressively groovier with each improvement.

The sustain pedal is pretty noisy at times. The spring makes noise if I press the pedal at just the
wrong angle. Maybe something is worn to the point of being sloppy. Gotta investigate that too.

No shortage of things to do. I'll post pics once all the dampers are in place.

d'2   

[DocWurly]

It's missing sustain bolts?  Yes, you definitely want ALL of those.  Check w Vintage Vibe and Chicago E. Piano company, maybe they have extras.

[pianotuner steveo]

Don't forget that you can adjust the strike line (front to back adjustment of the reeds) by slightly moving the entire reed bar. You can also heat the glue joint of the hammer that is too quiet and adjust the hammer itself in or out if it is only one key. (See the service manual) you likely want the hammer to hit further in for the sweet spot.

[devoid2]

That's good advice, and I'll keep it in mind. The amp goes in tomorrow for 3 prong upgrade and electrolytic caps replacement (and whatever the tech deems necessary.) I'm not entirely sure I'll keep this instrument, but I want to get it in pretty good shape for the next curator. The amp repair might turn the sound of this thing into something I can't part with--who knows?

cheers

d'2

[devoid2]

The amp is in the shop now and I don't expect to see it again for six weeks. Now, I'm thinking about the speaker. Re-cone or replace? I've re-coned before and it turned out well. How odd of a duck is this speaker? Was it a standard sort of speaker of its day?

[pianotuner steveo]

I believe it was standard- I think it's 12". Just remember the frequency range if a Wurlitzer is roughly 55hz - 2100 hz (plus overtones)
You don't need a speaker that reproduces 20-20k....

[devoid2]

I got the amp back, under $300 in work done. Nice shiny new IEC socket. I'm thinking seriously of selling the instrument. There are still some distorted and loud sounding reeds which annoy me, the damper work I did was good but not perfect (some notes aren't damping and I can't figure out why--I've fiddled with springs, lubricated, even contemplated putting small weights on the offending dampers.) I'm getting tired of the project and I think I need to move on.

With the original cost, repair on the amp, reeds, dampers and miscellaneous parts I'm still under $1000 into it. Do you think I can get that much for it?

d'2

[DocWurly]

Where do you live, if I may ask?  You can PM, I couldn't send you a message for some reason.

[devoid2]

I'm in West Stockbridge MA, on the NY border

[pianotuner steveo]

Pretty close to me.. but I don't work in MA...