The Gordon Printing Press is a clamshell-style platen letterpress that hinges a flat platen against a vertical bed holding the type chase, squeezing paper between them under high impression force. It solves the problem of producing short-run job printing — business cards, billheads, tickets — at high speed without the bulk of a cylinder press. A foot treadle or motor drives a flywheel and toggle linkage, automatically inking the form via a rotating ink disc on each cycle. A well-tuned 8×12 Gordon-type press runs 1,500 impressions per hour and still earns its keep in working letterpress shops today.
Gordon Printing Press Interactive Calculator
Vary press speed and ink-disc index angle to see sheet timing, ink-disc rotation rate, and synchronized clamshell motion.
Equation Used
This calculator converts the Gordon press impression rate into cycle timing and ink-disc indexing. IPH is impressions per hour and step_deg is the ratchet rotation of the ink disc each cycle. At 1,500 IPH and 30 deg per cycle, the disc turns 125 rev/hr, or about 2.08 rpm.
- One impression occurs per press cycle.
- The ink disc indexes once per cycle with no missed pawl steps.
- Press speed is steady over the calculation interval.
Inside the Gordon Printing Press
The Gordon press works on a clamshell motion. The bed — vertical, holding the locked-up type chase — stays largely stationary. The platen swings up to meet it, hinged at the bottom, and the two faces close like a book slamming shut. At the moment of closure, the toggle linkage straightens and multiplies the flywheel torque into several tons of impression force across the platen face. Paper sits on the platen between hand-set tympan packing, and on closure the type bites the sheet to a depth of roughly 0.05 to 0.15 mm depending on stock and desired bite.
While the press is open, a set of rubber or composition rollers rides up over the ink disc — a circular plate at the top of the bed that rotates a fraction of a turn every cycle to redistribute ink — then rolls down across the type face, charging it for the next impression. Timing here is everything. If the rollers contact the type before the platen clears, you smear ink onto the tympan. If the platen closes before the rollers retract, you crush a roller and bend a roller arm. The cam profile that drives roller travel and the platen toggle are mechanically linked through the main shaft, so synchronisation is fixed by the casting geometry — not adjustable on the fly.
The usual failure modes are platen-bolt loosening (you'll see uneven impression, heavy on one corner), worn toggle pins giving a soft or inconsistent squeeze, and ink-disc pawl wear that stops the disc rotating and starves the rollers. Trip lever failure is the dangerous one — the trip is what lets you skip an impression when feeding goes wrong, and a sticky trip will close the press on your fingers.
Key Components
- Bed and Chase: The bed is the vertical iron face holding the chase — a rectangular steel frame, typically 8×12 in or 10×15 in on Gordon-pattern presses, into which type and furniture are locked with quoins. The bed must sit perfectly parallel to the platen at full close; deviation beyond about 0.1 mm across the diagonal shows up as one corner printing heavy and the opposite corner ghosting.
- Platen: The platen is the flat hinged face that carries the paper and tympan packing. It pivots on bottom trunnions and is drawn up to the bed by the toggle. Platen-to-bed parallelism is set by four adjustment bolts at the corners and must be checked with a packing gauge any time you change form thickness.
- Toggle Linkage: Two pivoted links between the rocker shaft and the platen back. As the flywheel rotates, the toggle straightens at top-dead-centre, multiplying input torque into impression force on the order of 2 to 5 tons across an 8×12 platen. Worn toggle pins (>0.2 mm slop) give a mushy impression that varies cycle to cycle.
- Ink Disc: A circular cast-iron plate at the top of the bed, ratcheted by a pawl to rotate roughly 30° per cycle. This continually presents fresh ink under the rollers. A failed pawl spring stops disc rotation and the rollers strip ink off one zone, leaving a faded patch on the printed sheet within 50 to 100 impressions.
- Form Rollers: Two or three composition or rubber rollers, typically 1.625 in diameter on an 8×12, that traverse the bed on roller arms running in cast tracks. Roller height is set with trucks (end caps) that ride the bearer rails. Set the rollers 0.001 in proud of type-high (0.918 in) for clean inking; sit them on the type itself and you'll deboss the form into the rollers within an afternoon.
- Flywheel and Treadle: The flywheel stores rotational energy through the dead spots of the cycle and absorbs the impression shock. A typical 8×12 flywheel weighs 90 to 120 lbs. Treadle drive runs 800 to 1,200 impressions per hour; motorised conversion via a brake-clutch pulley pushes 1,500 to 2,000 IPH.
- Throw-Off Lever (Trip): A hand lever that disengages the platen at top of stroke so a misfed sheet doesn't pull an impression. A free-moving, well-lubricated trip is a safety-critical part — a stuck trip is the single most common cause of crushed-finger injuries on these presses.
Who Uses the Gordon Printing Press
The Gordon press and its direct descendants — Chandler & Price, Golding Jobber, Pearl, Craftsmen — defined commercial job printing from the 1850s through the 1960s, and a working subset of those machines still earns money in specialty letterpress shops. The combination of fast clamshell action, automatic inking, and a forgiving feed pattern made it the workhorse for any short-run printed item that needed to feel embossed.
- Specialty Stationery: Hatch Show Print in Nashville Tennessee runs Chandler & Price 10×15 platen presses (Gordon-pattern descendants) for poster and gig-flyer work on French Construction stock
- Wedding Invitation Printing: A boutique studio in Brooklyn New York operates a 1923 C&P 8×12 New Series job press for cotton-stock invitation suites at 0.10 mm bite depth
- Museum and Heritage Demonstration: The International Printing Museum in Carson California runs a treadle-driven Gordon Franklin press for live letterpress demonstrations on school tours
- Die Cutting and Scoring: A packaging prototype shop in Toronto Ontario uses a Heidelberg Windmill (clamshell descendant) for short-run die-cut paperboard cartons up to 0.024 in caliper
- Numbering and Perforating: A ticket printer in Chicago Illinois runs a Pearl Old Style No. 11 with a Leibinger numbering box for raffle and event tickets in 5,000-unit runs
- Foil Stamping: A luxury packaging shop in Milan Italy retrofits a Heidelberg T-platen with hot-foil heating plates to apply gold foil to perfume cartons at 100°C platen temperature
The Formula Behind the Gordon Printing Press
The number that matters on a Gordon-type press is impression force per unit of type area — pounds per square inch on the form. Too low and the type doesn't fully kiss the paper, leaving a patchy ghost print. Too high and you crush type face, dent the platen, or split the chase. At the low end of the typical job-press operating range, you're printing a full-coverage 8×12 form on soft cotton stock and need every pound the toggle can deliver. At the high end you're hitting a tiny 1×2 in business-card form, and the same toggle force concentrates into damaging pressure unless you back the platen off. The sweet spot for most letterpress work is roughly 400 to 800 PSI on the type face.
Variables
| Symbol | Meaning | Unit (SI) | Unit (Imperial) |
|---|---|---|---|
| Ptype | Pressure on the type face during impression | kPa or N/mm² | PSI |
| Ftoggle | Total impression force delivered by the toggle at top-dead-centre | N or kN | lbs-force or tons |
| Aform | Total inked area of the locked-up form (sum of all printing surfaces) | mm² | in² |
Worked Example: Gordon Printing Press in a Chandler & Price 8×12 New Series job press
A letterpress wedding-invitation studio in Asheville North Carolina is sizing impression force on a 1921 Chandler & Price 8×12 New Series running at 1,200 IPH. The toggle delivers a rated 6,000 lbs of impression force at full close. The studio prints three different forms on the same press in a single afternoon and needs to know what packing adjustments each requires.
Given
- Ftoggle = 6000 lbs
- Asmall (business card, 2×3.5 in) = 7 in²
- Anominal (invitation, 5×7 in) = 35 in²
- Alarge (full 8×12 menu form) = 96 in²
Solution
Step 1 — at the nominal operating point, a 5×7 in invitation form covering 35 in², calculate the type-face pressure:
That is too low for crisp letterpress bite on cotton stock. The press will need extra packing behind the tympan — typically two or three sheets of pressboard — to shim the form effectively closer to the platen and raise local pressure. After packing, effective pressure rises to roughly 500-700 PSI, the working sweet spot.
Step 2 — at the low-area end, a 2×3.5 in business card form, the same toggle force concentrates onto a much smaller area:
This is high enough to crush serif type face within a few hundred impressions if you run unpacked. The fix is to back off the platen bolts a quarter turn and pull packing sheets out — you want to throttle the toggle to deliver about 3,000 lbs to this small form, not the full 6,000.
Step 3 — at the high-area end, a full 8×12 menu form covering 96 in²:
That is well below the threshold for a clean impression on any stock heavier than newsprint. On a C&P 8×12 you simply cannot print a full-coverage 96 in² form with crisp bite — the toggle runs out of force. Working letterpress shops solve this by splitting the form into two passes or moving the job to a 10×15 press with a heavier toggle.
Result
At nominal — a 5×7 invitation on the C&P 8×12 — type-face pressure runs 171 PSI raw, brought up to the 500-700 PSI working range with two or three sheets of pressboard packing. The small business-card form sees 857 PSI and risks crushing type face unless you pull packing and back the platen off; the full-bed menu form sees just 63 PSI and won't print cleanly at all on this press size. If your measured impression looks weak when the math says it should be adequate, check three things: (1) toggle pin slop greater than 0.2 mm robs 10-20% of rated force across the cycle, (2) loose platen bolts let the platen rock under load and corner pressure drops, and (3) glazed composition rollers sit too low and the form never reaches type-high contact. Fix the rollers first — it's the cheapest of the three and accounts for most weak-impression complaints.
Gordon Printing Press vs Alternatives
The Gordon platen press isn't the only way to print, and choosing it over the alternatives comes down to run length, sheet size, and the kind of impression you want. Here's how it stacks up against the cylinder presses and modern digital alternatives that compete for the same jobs.
| Property | Gordon Platen Press | Vandercook Cylinder Proof Press | Heidelberg Windmill Platen |
|---|---|---|---|
| Speed (impressions per hour) | 1,200-2,000 IPH motorised | 150-300 IPH hand-cranked | 3,000-4,500 IPH |
| Maximum form area | 8×12 to 14.5×22 in depending on model | Up to 18×24 in on SP-25 | Up to 10×15 in |
| Impression force | 2-5 tons at toggle close | Cylinder roll, no toggle multiplication | 5-7 tons |
| Capital cost (working condition) | $2,500-$8,000 for restored C&P | $8,000-$25,000 for SP-15 | $15,000-$40,000 |
| Auto-feed capability | Hand-fed only | Hand-fed only | Pneumatic gripper auto-feed |
| Operator safety | High risk — open clamshell, hand feed | Low risk — operator behind cylinder | Moderate — gripper enclosure required |
| Best application fit | Short-run cards, invitations, tickets | Proofing, fine-art letterpress, posters | Mid-volume die-cut, foil, numbering |
Frequently Asked Questions About Gordon Printing Press
That's a platen-parallelism problem, almost always at the top platen-adjustment bolts. The platen pivots on bottom trunnions, so wear or loosening shows up first as the top of the platen sitting back from the bed at full close. Check with a packing gauge or a strip of 20 lb bond folded eight times — slip it between platen and bed at all four corners at top-dead-centre and feel for equal drag.
If the top corners are slack, snug the upper platen bolts a quarter turn at a time. If the trunnion bushings are worn (you'll see the platen rock when you push it by hand at top close), the press needs new trunnion pins — that's a job for a press mechanic, not a field fix.
The formula assumes the toggle delivers full rated force, but on a small form the platen often doesn't actually reach full close. The toggle is geometrically tied to the bed, and if your packing height plus form height plus paper doesn't add up to the designed gap, the toggle straightens before the type fully meets the paper.
Add packing — a sheet at a time — until the impression deepens. You're not adding force, you're shimming the system into the toggle's working range. This is also why C&P and Gordon manuals specify type-high as 0.918 in to four decimal places: the whole geometry is designed around that dimension.
For 5×7 and smaller invitation suites the 8×12 is the right call. It runs faster (lighter flywheel, less inertia), takes up less floor space, and matches the toggle force to the form area cleanly. The 10×15 only earns its keep if you're regularly printing forms above 50 in² or running heavy coverage on cotton stock thicker than 220 gsm.
The hidden cost on a 10×15 is the flywheel — 180 lbs versus 100 lbs on an 8×12 — which means a heavier motor, a bigger brake, and a stiffer floor. A lot of studios buy the 10×15 thinking bigger is better and end up wishing they'd stayed with the 8×12 they could feed more comfortably.
With the press at top-dead-centre and the flywheel locked, grab the platen and try to rock it toward and away from the bed. A healthy toggle gives you essentially zero movement — the linkage is straightened and self-locking. If you feel any perceptible play, you're looking at pin or bushing wear.
Measure with feeler gauges at the toggle joints. Anything over 0.005 in (0.13 mm) of radial play translates into mushy, inconsistent impression and accelerates further wear because the joint hammers itself every cycle. Re-bushing is the correct fix — don't shim it.
The pawl spring has either weakened or the pawl tip is worn round. The disc is rotated by a pawl that catches a ratchet on the disc back every cycle — if the spring tension drops, the pawl skips on heavy ink films because the disc resistance exceeds spring force.
Pull the disc, inspect the pawl tip for a flattened nose (it should be sharp), and check the spring with the disc off — the pawl should snap back smartly when you flick it. Replace the spring with the correct C&P or Gordon part; a hardware-store substitute will be the wrong rate and you'll be back inside the press in a month.
No, and this is the single most important safety rule on these machines. The throw-off (trip) is what disengages the platen if your hand is still in the press when the cycle reaches close. A sticky or non-functional trip is how operators lose fingers — there are no second chances on a 6,000 lb impression.
If the trip is slow to return or doesn't fully disengage the platen, stop the press and fix it before another sheet goes through. The fault is usually dried oil in the trip-lever pivot or a stretched return spring; both are 30-minute repairs. Run the press with a known-good trip or don't run it at all.
References & Further Reading
- Wikipedia contributors. Platen press. Wikipedia
Building or designing a mechanism like this?
Explore the precision-engineered motion control hardware used by mechanical engineers, makers, and product designers.
