Fender Rhodes Stage 88 — Vol 06: Action Regulation

This is the regulation volume of the refurbishment bench manual, and the most measurement-dense. With the keyboard assembly rebuilt and the harp ready to go back on (Vol 03 §“Keyboard assembly out of the case”; Vol 05 §“Mounting & coarse alignment”), this volume sets the six interlocking adjustments that decide how the Stage 88 plays: key height/leveling, key dip, escapement (let-off), strike line, damper regulation, and hammer tips, plus the period Miracle Mod that revives a soggy action. Every adjustment here carries a numeric target with a tolerance, a named tool, and at least one way it is commonly done wrong. The factory figures come from the Rhodes service manual Chapter Four — Dimensional Standards and Adjustments; the field practice and the parts come from Vintage Vibe, Steve’s Corner, and Chicago Electric Piano. Where the manual and a secondary source disagree on a zone boundary or a number, both are stated and the conflict is flagged — no value is invented.

Note: Every clearance in this volume is given in fractional inch and millimetre, and every numeric target is also drawn to scale in a dimension-annotated SVG. Hammer-tip hardness is in Shore durometer. The tone-generator side of the note (tine, tonebar, grommets, coarse alignment) is Vol 05; voicing the tine against the pickup by ear is Vol 07; tuning and tempering are Vol 08. This volume is the mechanical regulation that those passes assume is already correct.

The regulation sequence

Regulation is strictly ordered, because each step shifts the geometry that the steps after it depend on. The service manual states the dependency directly: “When Key Dip is changed, reestablishment of Escapement and Striking Line is required” (fenderrhodes.com, Chapter Four). The same cascade runs the whole way down — set a step out of order and the earlier work is invalidated. The order is:

1. Key height / leveling → 2. Key dip → 3. Escapement (let-off) → 4. Strike line → 5. Damper regulation → 6. Hammer tips.

Read the dependencies forward: leveling defines the rest height every later measurement is taken from; key dip sets how far the key (and therefore the hammer) travels, which changes the let-off gap; escapement positions the harp height, which moves the strike line; the strike line and any escapement change move where the damper meets the tine; and the hammer tips — if they are being replaced — reset the blow distance and send the work back up to escapement. The one wrinkle is that a hammer-tip change is a parts operation, like a tine change (Vol 05): graduated tips set their own escapement by height, so when tips are replaced they are fitted before escapement is dialed in, then escapement and everything downstream is redone. The list below is the regulation order; the tip section explains where a tip replacement slots in.

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dashed = changing a step forces re-doing the step(s) above a hammer-TIP replacement (parts change) loops back to escapement → strike line → dampers

Work top to bottom; never set a step before the one above it is final.

Warn: Do not regulate out of order to “save a step.” Setting the strike line before key dip and escapement are final is the most common version of this error — the harp gets positioned to a strike that key-dip and escapement changes then move, and the whole job is chased in circles. The manual’s rule is one-directional: change anything and re-establish everything below it (fenderrhodes.com, Chapter Four).

Key height & leveling

Leveling is step one because every later measurement — dip, escapement, strike line — is read from the key’s rest height. The naturals are set first to a single height, level along the keyboard and square to the key slip of the case; the sharps are then set to their own height relative to the leveled naturals. Height and level are trimmed with felt and paper punchings under the balance rail (the balance-rail pin each key pivots on), the felt setting the bulk height and the thin paper punchings fine-trimming each key to the line.

Tools: straightedge across the key tops; balance-rail felt and paper punchings (assorted thicknesses, Vol 03 §“Consumables”); the Avion black-key height tool for setting sharp height in relation to the leveled naturals (avionstudios.com); a flat-blade tool for lifting punchings.

Step 1 — Set and level the naturals

With the keys on the keybed, lay a straightedge across the natural key tops and sight the row: every natural front should sit at one height and the line should be level end to end and square to the key slip (vintagevibe.com, 5 Easy Ways to Make Your Rhodes Play Better).
Raise a low key by adding a paper punching under its balance-rail pin; lower a high key by removing one. Use felt punchings for coarse height and paper for the final thin trim.
Re-sight the whole row after every few keys — punchings interact, and a key set in isolation walks out of level when its neighbors move.

Step 2 — Set the sharps to the naturals

With the naturals leveled, set each sharp (black key) height in relation to the white keys using the Avion black-key height tool, which references the sharp off the already-regulated naturals (avionstudios.com).
Confirm the sharps are level along their own row and consistent in their step up from the naturals.

Naturals leveled to one height first; sharps then set to the naturals. Every later spec (dip, escapement, strike) is read from this rest height.

Warn: Level the naturals first, then set the sharps to them — never the reverse. Setting sharps to an unleveled natural row, or chasing individual keys without re-sighting the whole line, bakes a wandering height into the bed that every downstream spec inherits. And height/level is a balance-rail punching job (the pivot) — it is not the same adjustment as key dip, which is set at the action rail (next section). Confusing the two is the classic regulation mistake.

Key dip

Key dip is the downward travel of the key front before the action locks — “the distance the key travels downward before stop lock of the hammer cam and key pedestal are made” (vintagevibe.com). Too shallow and the note has limited expression and won’t let off cleanly; too deep and it “will require extra effort with a lack of soft touch” (vintagevibe.com).

Target: the service manual specifies dip of 3/8″ ± 1/32″ — “from 11/32″ to 13/32″ (9.525 ± 0.794 mm, i.e. 8.731 mm to 10.319 mm)” (fenderrhodes.com, Chapter Four). In the field, Vintage Vibe sets it “to your liking (usually 3/8″ ± 1/16″, i.e. ±1.588 mm either side)” — a looser working tolerance than the manual’s (vintagevibe.com). Both are stated; the manual figure is the reference.

Tools: a weighted key-dip block laid flat across the keys to read a good average dip (Avion “Weighted Key Dip Block,” avionstudios.com; Vol 03 §“The refurb toolkit”); shim stock for the action rail.

Step 1 — Measure the dip

Lay the weighted dip block flat across the key tops so it reads the average travel, and press a key fully down; the block’s reference reads the dip at the key front.
Confirm the reading falls in 11/32″–13/32″ (8.731–10.319 mm), target 3/8″ (9.525 mm) (fenderrhodes.com, Chapter Four).

Step 2 — Adjust by shimming the action rail

To change dip, shim the action rail up or down — raising the rail raises the hammer-cam stop-lock, so the key pedestal travels farther before lock-up and dip increases; lowering the rail reduces dip (Vol 03 §“Action rail & harp supports”: “the action rail height is the key-dip adjustment”).
Re-measure with the dip block and repeat until every key reads within tolerance.
Because dip changed, re-establish escapement and strike line afterward (fenderrhodes.com, Chapter Four).

Dip is set by ACTION-RAIL height (Vol 03 §“Action rail & harp supports”). After any dip change, re-do escapement and strike line. Manual: 3/8″ ±1/32″ (fenderrhodes.com Ch.4) · field tolerance ±1/16″ (vintagevibe.com).

Warn: Adjust dip by shimming the action rail, not by adding front-rail punchings. Front-rail punchings limit travel and are the wrong tool for setting dip on a Rhodes — the dip is fixed by where the action rail puts the hammer-cam stop-lock. This is the single most common Rhodes dip error: technicians reach for the front punchings out of acoustic-piano habit and never get a clean, even dip (Vol 03 §“Action rail & harp supports”). And remember the cascade — every dip change forces escapement and strike line to be re-set (fenderrhodes.com, Chapter Four).

Escapement / let-off

Escapement (let-off) is the blow distance — the gap between the hammer tip and the tine at the moment the hammer escapes — measured by pressing the key to its farthest point “without going into after-touch” (vintagevibe.com). It is the single biggest lever on how evenly the piano responds to a soft touch.

It must be GRADUATED, never uniform. The ideal for the most responsive touch is a tiny 1/32″ (0.794 mm) gap, but “the whipping action of the tine in response to the hammer blow increases as it becomes longer toward the bass end of the keyboard, making this ideal setting impossible” (fenderrhodes.com, Chapter Four). A bass tine set as tight as a treble tine double-strikes — the long, slow tine swings back up into the hammer before it has cleared. So the gap is opened up in the bass and closed down in the treble:

Zone	Service manual Ch.4	Field / secondary practice	mm (field range)
Extreme bass	1/4″ min – 3/8″ max	3/16″ – 3/8″ (Vintage Vibe / common)	4.762 – 9.525 mm
Mid	(graduated between)	1/16″ – 1/8″	1.588 – 3.175 mm
Extreme treble	1/32″ min – 3/32″ max	1/32″ – 3/32″	0.794 – 2.381 mm

Conflict flagged. Three sources draw the zones slightly differently: the manual Ch.4 gives extreme bass 1/4″–3/8″ and extreme treble 1/32″–3/32″; common field practice / Vintage Vibe opens the bass floor to 3/16″ and inserts a mid band of 1/16″–1/8″; and Steve’s Corner describes a continuous taper from “approximately 1/2″ at low E to approximately 1/16″ at high E” (fenderrhodes.com Chapter Four; vintagevibe.com; fenderrhodes.com/service, Escapement & Strike Line). All three agree on the shape — wide bass, tight treble, smoothly graduated — and differ only at the boundaries. None is invented; pick the manual figures as the reference and graduate smoothly between them.

Escapement is set by four means, in rough order of use: the tone-bar coil-spring height (the primary global adjustment), harp-support shims at the extremes, the graduated hammer tips (which build escapement into their own height — see §“Hammer tips”), and shaving the side support block to remove a global excess.

Tone-bar coil-spring height — the main adjustment. Each tone bar rides on a coil spring whose height sets that bar’s distance from the hammer. “The height of each Tone Bar Assembly can be raised to 1/2″ (12.700 mm) or lowered to 3/16″ (4.762 mm) — factory setting is 3/8″ (9.525 mm)” (fenderrhodes.com, Chapter Four). Raising the bar opens the escapement gap; lowering it closes it.
Harp-support shims at the extremes. Steve’s method adjusts escapement globally by “inserting a spacer between the harp support blocks and the harp” (fenderrhodes.com/service). Used to bias the whole bass or treble end.
Graduated hammer tips. Height-graduated tips “offer an immediate escapement without changing the height of the harp” (vintagevibe.com) — they set the gap by their own profile.
Shaving the side support block. Where the whole harp sits too high (global escapement excess), the side support block is shaved down to drop it.

Tools: a feeler/escapement gauge or shim stock to read the gap; the 6″ long-shaft #2 Phillips for the tone-bar springs (Vol 03 §“The refurb toolkit”); harp-support shim stock; a sharp chisel/plane for the side support block.

Step 1 — Read the gap, key by key

Press a key to its farthest travel without after-touch and read the hammer tip-to-tine gap with the gauge (vintagevibe.com).
Check the bass, middle, and treble against the graduated targets above — expect a wide bass gap and a tight treble gap, smoothly graduated between.

Step 2 — Graduate the gap

Set the bass wide enough that no long tine double-strikes — manual 1/4″–3/8″ (6.350–9.525 mm), opening the coil-spring height toward 1/2″ (12.700 mm) if a bass tine still re-strikes.
Taper smoothly through the mid (1/16″–1/8″, 1.588–3.175 mm) to the treble (manual 1/32″–3/32″, 0.794–2.381 mm), closing the coil-spring height toward 3/16″ (4.762 mm) at the top.
Bias whole ends with harp-support shims; if the entire harp sits too high, shave the side support block to drop it globally.

Warn: Never set escapement uniformly across the keyboard. A bass tine given the treble’s tight 1/32″ gap double-strikes — the long tine swings back into the hammer before it clears — which reads as a stuttering, choked bass. Graduate the gap wide-to-tight, bass-to-treble, every time (fenderrhodes.com, Chapter Four). And set the primary adjustment at the tone-bar coil-spring height before reaching for harp shims or shaving the support block.

Strike line

The strike line is where along the tine the hammer lands. The manual fixes it by a reference dimension and moves it by sliding the whole harp:

Target. “Proper Striking Line is assured by setting the Harp in such a way as to arrive at an approximate dimension of 2-1/4″ (57.150 mm) between the leading edge of the Hammer Tip and the leading edge of the Tone Generator … at the extreme Bass. At the extreme Treble this dimension is approximately 1/8″ (3.175 mm)” (fenderrhodes.com, Chapter Four). The reference is measured from the tone-generator (tonebar) block, not the free tine tip — Steve’s Corner adds that the usable strike point is “past the tapered section” of the tine as it exits the block (fenderrhodes.com/service). (The treble ~1/8″ figure was re-verified against Chapter Four directly and confirmed.)

Tools: the #2 Phillips to loosen the harp’s side screws; ears (the strike line is verified by ear, the “sweet crack”).

Step 1 — Free the harp to slide

Remove or loosen the screws on each side of the harp so the harp can be slid fore and aft while notes are struck (vintagevibe.com). Steve’s method keeps “one harp mounting screw loosely in place” as a pivot (fenderrhodes.com/service).

Step 2 — Slide to the sweet crack

Strike reference notes — Cs and Fs up and down the keyboard — while slowly sliding the harp toward and away from you (vintagevibe.com).
Listen for the harp position that “consistently produces the clearest note” — the sweet “crack” of the tine — across the whole keyboard (fenderrhodes.com/service; vintagevibe.com).
Cross-check the reference dimension: roughly 2-1/4″ (57.150 mm) bass tapering to ~1/8″ (3.175 mm) treble, hammer-tip leading edge to tone-generator leading edge.

Bass tone gen.

2-1/4″ (57.150 mm) hammer-tip leading edge → tone-gen leading edge

Treble tone gen.

~1/8″ (3.175 mm) strike point just past the tapered section Set by sliding the whole harp fore / aft loosen side screws; strike Cs & Fs; slide for the sweet “crack” up the keyboard (vintagevibe.com) Manual Ch.4: 2-1/4″ bass → ~1/8″ treble (both re-verified). A taper, not a constant — the harp pivots the whole line.

Warn: The strike line is one harp position for the whole keyboard, set by sliding the harp — it is not set per note. Chasing a single dead note by moving the harp pulls every other note off its strike. Set the harp to the best overall sweet crack (Cs and Fs, bass to treble), and trace a stubborn single note to its tine, grommet, or pickup instead (Vol 05; Vol 07). And re-do the strike line after any escapement or key-dip change — both move it (fenderrhodes.com, Chapter Four).

Damper regulation

The damper sits on the tine at rest and lifts off when the key is played (and when the sustain pedal lifts all dampers via the release bar, Vol 03 §“Damper release bar”). Two things are regulated: rest contact and lift height.

Targets. At rest the damper must sit firmly on the tine so the note stops cleanly; when the key is depressed the damper must clear the tine — “Damper Clearance should be 3/8″ to 1/2″ (9.525 mm to 12.700 mm)” of lift (fenderrhodes.com, Chapter Four). The sustain pedal lifts all dampers together.

Tools: the damper arms / damper module (Vol 03 §“Damper module”); the damper release bar; replacement bridle straps if perished (Vol 03 §“Consumables”).

Step 1 — Set rest contact

With the key at rest, confirm each damper presses firmly on its tine — enough to stop the note dead, not so hard it bends the tine or kills sustain prematurely.
A note that rings on after release has a damper not seating; a note that sounds choked or short has a damper too firm or mis-positioned (cross-check against a grommet/voicing fault, Vol 05).

Step 2 — Set lift height

Depress the key and confirm the damper lifts 3/8″–1/2″ (9.525–12.700 mm) clear of the tine (fenderrhodes.com, Chapter Four).
Press the sustain pedal and confirm the release bar lifts every damper together to the same clearance.
Re-check rest contact after — any escapement readjustment “will change the damper settings, so they will need to be readjusted also” (fenderrhodes.com/service).

At rest tine damper arm firm contact

Keyed (or pedal down) tine

3/8″–1/2″ 9.525–12.700 mm

Sustain pedal lifts ALL dampers via the release bar (Vol 03). Any escapement change shifts the damper — re-check rest contact after. fenderrhodes.com, Chapter Four (lift 3/8″–1/2″).

Warn: Regulate dampers after escapement and strike line, not before — “any readjustment of the escapement will change the damper settings” (fenderrhodes.com/service). Setting dampers first means re-doing them. And a damper that won’t quiet a note is not always a damper fault: confirm the tine, grommet, and pickup first (Vol 05) before bending damper arms.

Hammer tips

The hammer tip is the wear part that decides attack and timbre. Rhodes graduated both the hardness and the height of the tips across the keyboard. The tone relationship is direct: a soft tip gives a rounded “thunk” weighted to the fundamental; a hard tip gives a bright “clank” with “stronger upper harmonics.” Steve’s rule of thumb: “too soft a tip for a particular note and the sound has a ‘thunk’ to it; too hard a tip and the sound has a ‘clank’ instead” (fenderrhodes.com/service, Hammer Tips).

Durometer & height zones

Rhodes settled on roughly five hardness gradations bass-to-treble. The Shore-durometer values differ between sources — the conflict is flagged, not resolved:

Zone (bass → treble)	Steve’s Corner, 73-key (key range)	Shore (Steve’s)	Modern field (Vintage Vibe / Avion)
1 (bass)	keys ~00–23 (Black)	~30	~40 (Red)
2	keys ~24–33 (Red)	~50	~50 (Green)
3 (mid)	keys ~34–43 (Yellow)	~70	~70 (Yellow)
4	keys ~44–57 (Black)	~90	~90 (White)
5 (treble)	keys ~58–81 (Maple + shrink tube)	hard maple	wood core

So the canonical progression is ≈ 30 / 50 / 70 / 90 / hard maple (Steve’s Corner), with modern kits sold as ≈ 40 / 50 / 70 / 90 / wood and the exact key boundaries varying by supplier and by 73- vs 88-key bed (fenderrhodes.com/service; vintagevibe.com, Definitive Guide to Hammer Tips; avionstudios.com). Tip height is graduated too: roughly 1/4″ (6.350 mm) in the bass to 7/16″ (11.112 mm) in the treble — a 3/16″ (4.762 mm) overall increase, bass to treble (fenderrhodes.com, Chapter Four). Original square tips were “3/8″ (9.525 mm) square” before the height-graduated profile appeared (fenderrhodes.com/service).

Square → graduated cutover. The tip profile changed from a square/rectangular block to the height-graduated (slightly triangular) tip during the production run. The sources do not give a clean year and do not map it to a clean Mark I/Mark II split — Steve’s notes only that “later, they changed shape,” and Vintage Vibe dates the felt→neoprene change to ~1970–71 but gives no firm square→graduated date. The change is commonly placed around ~1977, but this is approximate. Verify per keybed by inspecting the actual tips, and flag the era accordingly — do not assert a clean Mk I/II boundary (fenderrhodes.com/service; vintagevibe.com).

Tools: pliers (pull the old tip); a sharp X-Acto knife (scrape residue; shave a hardened tip); super glue (attach the new tip); the correct graduated hammer-tip kit (Vol 03 §“Consumables”).

Step 1 — Diagnose

Replace tips that are grooved (a notch worn where they strike the tine) or hardened (gone glassy, giving a “clank” where a “thunk” belongs) (fenderrhodes.com/service).
Keep the hammers in keyboard order (Vol 03 §“Handling & storing parts”) — the durometer is graduated, so a tip out of zone mis-voices that note.

Step 2 — Shave (limited) or replace

To soften a tip that has hardened only at the strike face, shave with the X-Acto knife just under the hard spot to expose fresh softer rubber. Because shaving changes the tip height (and therefore escapement), “it is only recommended to do it twice” (fenderrhodes.com/service).
To replace: pull the old tip off with pliers, scrape off the remaining rubber and glue residue with the knife, apply super glue to the hammer, and press on the new tip of the correct durometer for that zone (fenderrhodes.com/service).
Because new graduated tips set their own escapement by height, re-establish escapement, strike line, and dampers afterward (the loop-back in §“The regulation sequence”).

Colors here are a soft→hard hardness RAMP only — NOT the Rhodes factory color code (e.g. Shore 30 = Black, not red); see the prose table above for the real codes. Durometer values conflict by source: Steve’s 30/50/70/90/maple vs. modern 40/50/70/90/wood — flagged, not invented. Shave a tip max ~twice.

Warn: Shave a tip at most about twice. Each shave lowers the tip, which changes escapement; past two shaves the height is too far gone and the tip is fitter for the bin than the bench — replace it (fenderrhodes.com/service). And keep the hammers in keyboard order: fitting a treble-hard tip in the bass (or vice-versa) mis-voices the note no matter how the rest is regulated. Do not state the square→graduated change as a clean Mark I/Mark II split — verify the actual tips on the keybed in hand.

The Miracle Mod

The Miracle Mod (also “bump mod” / “pedestal mod”) is an action modification — which is why it lives in this volume and not Vol 05. It adds a small rounded bump under the sloping face of the hammer cam / key pedestal, so that as the key is pressed the cam rolls over the bump as a leverage point and the key “engages the hammer much more quickly, leading to greater responsiveness and a lighter feel” (jupitervintagepianos.com, What is the Bump Mod?; vintagevibe.com, Miracle Mod). It is the cure for a soggy, sluggish action.

History. The mod revives a 1960s Rhodes feature — early pianos had a rounded bump added to the pedestal via a metal clip-on — that was lost on the 1972–1977 models. It is recommended across that whole 1972–77 range and “works best on earlier pianos in that range” (vintagevibe.com; shadetreekeys.com, Miracle Mod). Late-‘75 to ‘77 pianos used felt on the hammer cam, leaving the key pedestal bare; the shop practice is to remove the cam felt and install a proper bump on the pedestal — felt should never be used as the bump (vintagevibe.com).

Tools: the Miracle Mod / bump kit (Vintage Vibe, Avion “Wonderbump,” or equivalent — the molded bumps, not felt); adhesive per the kit.

Step 1 — Decide whether it applies

Confirm the piano is a 1972–1977 model with a soggy/sluggish action and either a bare pedestal or felt-on-cam (vintagevibe.com).

Step 2 — Fit the bump

If the cam carries felt, remove it; fit the molded bump under the sloping side of the hammer cam / on the key pedestal per the kit (vintagevibe.com).
Re-check key dip and escapement afterward — the bump changes the cam/pedestal engagement geometry, so the action is re-regulated from §“Key dip” down.

Effect: key engages the hammer sooner → faster, lighter, less “soggy” action. An ACTION mod (this volume), recommended for 1972–77. Re-check key dip + escapement after fitting (jupitervintagepianos.com; vintagevibe.com; shadetreekeys.com).

Warn: Do not substitute felt for the molded bump — “felt should never be used as a bump mod”; the felt-on-cam arrangement of late-‘75–‘77 pianos is the problem being fixed, not the fix (vintagevibe.com). And the Miracle Mod is an action change: after fitting it, re-regulate from key dip down — the cam/pedestal geometry has moved.

Sources

fenderrhodes.com, Chapter Four: Dimensional Standards and Adjustments (Rhodes Keyboard Instruments factory service manual) — the load-bearing factory figures and the ordering rule: key dip 3/8″ ± 1/32″ (11/32″–13/32″; 9.525 ± 0.794 mm, i.e. 8.731–10.319 mm); “When Key Dip is changed, reestablishment of Escapement and Striking Line is required”; escapement ideal 1/32″ (0.794 mm) but graduated because tine whip increases toward the bass, extreme bass 1/4″–3/8″ (6.350–9.525 mm), extreme treble 1/32″–3/32″ (0.794–2.381 mm); tone-bar assembly height raisable to 1/2″ (12.700 mm) or lowerable to 3/16″ (4.762 mm), factory 3/8″ (9.525 mm); striking line ~2-1/4″ (57.150 mm) bass to ~1/8″ (3.175 mm) treble, hammer-tip leading edge to tone-generator leading edge; damper clearance 3/8″–1/2″ (9.525–12.700 mm); hammer-tip heights ~1/4″ (6.350 mm) bass → 7/16″ (11.112 mm) treble, a 3/16″ (4.762 mm) increase.
fenderrhodes.com/service, Steve’s Corner — Escapement & Strike Line — escapement as a continuous taper “approximately 1/2″ at low E to approximately 1/16″ at high E” (a third zone-boundary reading, flagged against Ch.4); adjust escapement “by inserting a spacer between the harp support blocks and the harp”; “any readjustment of the escapement will change the damper settings”; strike point “past the tapered section” of the tine; set the strike line by sliding the harp toward/away with one mounting screw loosely in place, listening for the clearest note.
fenderrhodes.com/service, Steve’s Corner — Hammer Tips — durometer zones (73-key) ~30 / 50 / 70 / 90 / hard maple (Black/Red/Yellow/Black/maple); original tips “3/8″ square,” later “changed shape”; “too soft a tip … ‘thunk’ … too hard … ‘clank’,” hard tips give “stronger upper harmonics”; shave “just under the hard spot” to restore softness, “only recommended to do it twice”; pull old tip, scrape residue, super-glue the new tip. No firm square→graduated year or Mark I/II split.
vintagevibe.com, 5 Easy Ways to Make Your Rhodes Play Better — key bed set to height, key dip “usually 3/8″ ± 1/16″,” keys leveled and squared to the key slip; dip is “the distance the key travels before stop lock of the hammer cam and key pedestal”; escapement is the “blow distance” between hammer tip and tine read at full travel without after-touch; strike line reset by loosening the harp side screws and sliding while striking Cs and Fs for the sweet “crack.”
vintagevibe.com, The Definitive Guide to Fender Rhodes Hammer Tips and avionstudios.com, Hammer Tip Sets — modern graduated-tip kits at ~40 / 50 / 70 / 90 / wood, color-coded zones with key-range boundaries varying by 73-/88-key; graduated tips “offer an immediate escapement without changing the height of the harp” and give “the brightest sound and the most articulation”; felt→neoprene ~1970–71; no firm square→graduated date (flagged).
avionstudios.com — Weighted Key Dip Block (reads average dip) and Black Key Height Tool (sets sharp height in relation to the leveled naturals): the two Rhodes-specific regulation gauges used here (carried from Vol 03).
vintagevibe.com, Fender Rhodes Action “Miracle Mod” Kit and How to Install the Miracle Mod; jupitervintagepianos.com, What is the Bump Mod?; shadetreekeys.com, Miracle Mod — the bump under the hammer cam / key pedestal as a leverage point for a faster, lighter action; revives the 1960s clip-on bump; recommended for 1972–1977 pianos (best on earlier ones); late-‘75–‘77 used felt on the cam (bare pedestal), and felt is never the correct bump.
Cross-references: the tine/tonebar fork, grommets, and coarse tonebar alignment the escapement springs ride on are Vol 05 (Tone Generator); the action rail whose height sets key dip, the dip block / black-key tool, the damper module and release bar, and keeping hammers in keyboard order come from Vol 03 (Tools, Bench Setup & Teardown); fine voicing of the tine against the pickup by ear (the “bark”) is Vol 07 (Voicing & Tone); and retuning after parts work (the tuning spring, equal vs. stretch, the strobe method) is Vol 08 (Tuning & Tempering).

Flagged as conflicting or unverified, not invented: (1) escapement zone boundaries — the manual Ch.4 (bass 1/4″–3/8″, treble 1/32″–3/32″), Vintage Vibe (bass floor 3/16″, mid 1/16″–1/8″), and Steve’s Corner (continuous ~1/2″ low-E → ~1/16″ high-E) draw the bands differently; all agree on the wide-bass/tight-treble shape, and all three readings are stated rather than averaged. (2) Hammer-tip durometer values — Steve’s ~30/50/70/90/maple vs. modern field ~40/50/70/90/wood, with key-range boundaries varying by 73-/88-key bed and supplier; both stated. (3) The square→graduated tip cutover — no source gives a clean year or a clean Mark I/Mark II split; the commonly-cited ~1977 is approximate and must be verified per keybed by inspecting the tips. (4) The manual’s mid-zone escapement number is not given explicitly in Ch.4; the 1/16″–1/8″ mid band is field practice (vintagevibe.com), labeled as such. No dimension, durometer, or year has been invented; every factory figure is quoted from Chapter Four and every field figure is attributed to its named source.