How to Clean and Press Comic Books. FREE Online Guide by KaptainMyke

WHAT IS COMIC BOOK PRESSING?
Comic book pressing is the process of flattening out a comic book that has been wrinkled or damaged. Comics can get bent during shipping or have creaselines from heavy reading. Good news: Comic Books can be pressed using a t-shirt heatpress machine, a book press, a stack of short boxes, or anything heavy and flat. The idea is simple: to smooth out the waves and bumps on the cover of a comic book. This makes the overall grade and eye appeal of the book increase considerably. Comic book pressing is not restoration, more like comic book conservation. The difference can sometimes mean thousands of dollars when discussing high dollar key comic books. Do NOT press a comic book with an iron.

HOW LONG DOES IT TAKE TO LEARN?
Every person is different. Do you have the ability to troubleshoot? Life experiences, patience thresholds, busy schedules, attention to detail, and climate can depend on the speed of your learning process. For the average person, it will take a minimum of 2 years to fully grasp all aspects of comic book cleaning and pressing. There are varying degrees of learning the different eras, thickness of books, spine bindings, and paper quality. Experience, time, and patience all play an important factor in this experience. As with anything else in life, it all will depend on how much time you put into learning this procedure. Over time, you will continue to learn new tricks, and develop your own favorite methods and shortcuts as well.

THE PRESS MACHINE
There are 3 main types of machines you’ll often hear about:

Each machine has its own strengths and learning curve, and as you explore them you’ll get a sense of which fits your setup best.

THE IMPORTANCE OF YOUR PRESSING ROOM ENVIRONMENT
Pressing isn’t just about machines — it’s also about the space you work in. Paper is highly sensitive to temperature and humidity, which means the environment around your press can directly affect your results. The ideal range for pressing is 70–75°F (21–24°C) with a relative humidity of 40–50%. This range keeps the paper fibers flexible enough to relax during pressing, but not so damp that they swell or wrinkle. If your room is too humid, the paper can absorb excess moisture, which often leads to problems like spine waves, rippling, or even mold growth if books are left unchecked. On the other hand, if your environment is too dry, the paper becomes brittle and less responsive to pressing, which increases the risk of tears, split spines, or color rub.

MAINTAIN CONTROL OF YOUR ENVIRONMENT
To control your environment, many collectors use tools like digital hygrometers (to measure temperature and humidity), dehumidifiers or humidifiers (to stabilize the air), and even air purifiers to keep dust away from books during cleaning and pressing. By keeping your workspace stable, you’re not only improving your pressing success rate but also protecting your collection from long-term environmental damage.

• Dehumidifier or humidifier – to keep relative humidity steady around 40–50%.

• Stable room temperature (70–75°F) – avoid hot attics, garages, or damp basements.

• Air purifier – keeps dust and particles away from books during cleaning and pressing.

• No direct sunlight – sunlight can cause heat fluctuations and fade inks.

• Climate consistency – don’t move books in and out of humid vs. dry spaces during pressing.

• Avoid “problem rooms” – open loft areas, high foot traffic zones, kitchens, bathrooms, and laundry rooms all cause big swings in humidity and should never be used for pressing or storing comics.

THE ORDER OF OPERATIONS
When performing comic book cleaning and pressing, it’s critical to follow the Order of Operations so you don’t waste time, cause damage, or miss important details. Following the Order of Operations isn’t just about being organized — it’s about protecting your comics and building good habits. Pressing is a delicate process, and every step prepares the book for the next one. If you skip inspection, you might waste time on a comic that’s unpressable or even damage it further. If you clean after pressing, you risk grinding dirt into softened paper fibers. If you forget reversion checks or proper storage, defects may come back before grading. Each step is like a link in a chain — when followed in order, the chain is strong; when skipped or scrambled, the chain breaks.

The Order of Operations for Cleaning & Pressing Comic Books:

1. Inspection for Rejects – Identify books that are too fragile or have too many unpressable defects. PRO TIP! Color-breaking creases, ink loss, or brittle paper can’t be fixed by pressing.

2. Photography (Before) – Document the book’s condition to track progress. PRO TIP! Take clear shots under good light; clients appreciate strong before/after records.

3. Dry Cleaning / Stain Removal – Remove surface dirt or light soiling before adding heat or moisture. Follow basic free dry cleaning tips at this guide. Warning: Never dry clean after pressing — it may be more difficult to lift light soiling or dirt once it’s been flattened into the paper.

4. Humidity Tank – Relax the paper fibers to prepare for reshaping. PRO TIP! Keep humidity controlled (40–50%) in the press room — too much causes waves or oversaturation.

5. Dent Removal – Address stubborn divots, impressions, or spine dents while the paper is malleable from the humidification step. PRO TIP! Use tools like a steam gun, steel ball bearing, and a tack iron for targeted dent removal.

6. Pressing – Apply controlled heat and pressure to flatten defects. Warning: Press at safe temperatures (around 130–160°F) — overheating risks gloss bubbling, flaring, warping, fusion. Always allow a suitable wait time of 12-24 hrs. before removing from press machine.

7. Reversion Check – Let the book rest for several days and monitor for defects returning. PRO TIP! Store in bag/board flat for 2–5 days; unstable climates cause reversion.

8. Photography (After) – Record the results for comparison and grading prep. PRO TIP! Side-by-side before/after photos prove your work and protect against disputes.

9. Proper Storage – Bag, board, and keep the book in a stable environment. Warning: Avoid basements, attics, or kitchens — heat and humidity swings cause reversion.

10. Shipping / Grading – Send the book safely once fully settled. PRO TIP! Use sturdy Gemini mailers or CGC-approved boxes to prevent shipping dents.

PRACTICE ON PRESSING 7 TYPES OF BOOKS
You will need to practice first on 7 basic types of comic books to learn the process slowly. Practice on your own books first. Practice treating each book as if it were priceless.

Golden Age Books are brittle, require steam or humidity, and require extra care when handling.
Silver Age Books can also be quite brittle, and have edgewear like crazy. Watch for rusty staples.
Bronze Age Books have a different type of paper, semigloss and with inserts.
Modern Age Books with Glossy Magazine Paper books can have pages stick together if too hot! Under 150F and under 10 minutes at a time. The pages will stick together otherwise and you will create a razor blade comic book.
Foil books (Convention exclusives) are more intimidating if anything. Watch your fingerprints! Always wear gloves. Same rules apply as if it were a glossy modern with glossy pages. Too hot and too long will ruin the book!
Digital Code Inserts Marvel and DC both now have online digital code inserts found at the last 4-6 pages. You will need to use cardstock paper to prevent the 1″ or 2" square digital code from imprinting on last 4-5 pages and back cover.
Gimmick Books are books that have die cut, embossed, glow-in-the-dark, hologram, or lenticular covers. Embossed covers will need to be cushioned with cardstock paper. Gimmick books can be safely pressed using less pressure under low heat (150-155 degrees) for 5-7 minutes and left overnight in a cold press machine. Heating up glow-in-the-dark comic book covers actually re-activate the glow powder crystals in the paint, which effectively make the glow effect appear brighter with bolder colors.

All of these books were pressed using methods outlined in this guide and on my youtube channel. You too, can achieve similar results.

STACKING LAYER RECOMMENDATIONS
Before beginning any procedures outlined on this page, make sure that all comics have been thoroughly dry cleaned and wiped of any fingerprints or light scratches. To learn more about pressing and using all the stacking layers correctly, please follow the diagram found below. You will insert paper or cardstock layers inside the interior pages of a book in order to push out the dents and defects during the actual pressing procedure. The Basic Press is the core method for all satellite formulas. Formula recommendations are altered depending on the age of the book, type of cover, and the type of interior paper stock. The Basic Press Formula work well for most comics and magazines but is largely dependent on the fragility of the cover and the spine.

PRESSING OPTIONS

Books are typically placed in the press machine with the most defects facing up towards the heated platen. You have a few options for the stacking layer materials (choose one option for each layer):

INTERIOR PAPERSTOCK (INTERIOR PAGES OF BOOK)
• 65 LB CARDSTOCK PAPER (Primary stacking layer, underneath covers or after pages 1 or 2)
• 110 LB CARDSTOCK PAPER (Staple protection, insert protection)
• 20 LB INKJET COPY PAPER (Secondary stacking layer, underneath covers or after pages 1 or 2)
• SILICONE RELEASE PAPER (Dent removal, before any insert envelope adhesive backing strip)
• NONE (Reset underhanging covers)

INSERT PROTECTION (BEFORE AND AFTER EACH INSERT PAGE)
• 65 LB CARDSTOCK PAPER (Recommended for most inserts)
• 110 LB CARDSTOCK PAPER (Recommended for DC Comics digital code squares)
• 20 LB INKJET COPY PAPER (5 sheets, if you do not have 65 lb cardstock paper)

CENTERFOLD PROTECTION (CENTER OF BOOK)
• MAGAZINE-SIZE BACKER BOARD (Single)
• TWO MAGAZINE-SIZED BACKER BOARDS (Double)
• FULL-BACK (Substitute for using two magazine-sized backer boards)
• 65 LB CARDSTOCK PAPER (Prestige Format, Squarebounds, Giant Sized glued spines)

EXTERIOR PAPER STOCK (OUTSIDE BOOK COVERS)
• 20 LB INKJET COPY PAPER (All press stages on all comic books and magazines)
• SILICONE RELEASE PAPER (Dent removal)
• 110 LB CARDSTOCK PAPER (Die cut covers, gimmick covers, embossed covers)

EXTERIOR CARD STOCK (OUTSIDE BOOK COVERS)
• MAGAZINE-SIZE BACKER BOARD (Top and bottom outermost stacking layers)

EXTERIOR RIGIDITY (OUTSIDE THE EXTERIOR CARD STOCK LAYERS)
• STAINLESS STEEL PLATES (x2) (All press stages on all comic books and magazines)
• ALUMINUM PLATES (x2) (All press stages on all comic books and magazines)
• ½” or ¼” THICK FOAM BOARD (Flattening spines – cover side down, staples up)
• THREE MAGAZINE BACKER BOARDS (x2) (Recommended if you don’t have plates)

THE BASIC PRESS METHOD

Make sure all dry cleaning is done first. The Basic Press Method is the basis for all satellite methods outlined on this page. This is the full summary while performing the Basic Press Method:

1. Place comic book on an elevated platform in a humidity tank with a fresh gallon of boiling water. The water line should be 1" to 2" from the bottom of tank. Vintage comic books with flat matte interior pages should be placed inside the humidity tank for 1 hour. Brand-new comic books with glossy thin interior pages should be placed in the humidity tank for no longer than 10 to 15 minutes.

2. Perform dent removal procedures if required. For vintage books with flat matte interior pages, apply a damp cotton round to defect area and roll a steel ball bearing around gently over the defect. Any book with glossy thin magazine style interior pages should have light steam applied to the defect area using a cut out backer board. Alternate methods with a tack iron to apply localized heat to defect area. Proceed to Step #3 while you are still finishing up dent removal.

3. Open press machine. Find the power switch on your press machine. Turn ON the press machine.

4. Preheat machine to the recommended temperature and time duration as outlined in the Basic Press Method stacking formula. 150F for 10 minutes.

5. Dry mount laminating press machines should set the temperature to 10 degrees cooler than recommended due to slower warmup and cooldown times, which equals longer heat.

6. Turn pressure adjustment knob and measure gap thickness for spine of book. The pressure adjustment knob for swing arm machine is located at the top center of unit. For clamshell and swing arm machines, turning the knob clockwise increases pressure. For dry mount laminating press machines, there will be two knobs. The larger knob must be loosened first before adjusting pressure with smaller knob. The smaller knob must be turned counter-clockwise to increase pressure, which is the opposite of the two other machines.

7. Place bottom steel plate on silicone mat of press machine. Plates should always be galvanized, stainless-steel, or aluminum to prevent rust. Sizes can be 15x15, 12x10, 9x12 or 8x11.

8. For books printed from 1940-2001 with flat matte interior pages that feature heavy deep denting or deep indentations to covers, proceed with Hot Shot method (a damp cotton round, squeezed out between 2 dry cotton rounds) on any localized areas that require additional humidity. No Hot Shots to any book with thin glossy interior pages. Only light steam should be applied using a Cut Out backer board to modern books with glossy thin interior pages.

9. Follow all stacking layer instructions from the provided free Basic Press stacking formula. If a comic book has a shredded spine or spine splits greater than 1/8", place the 65lb cardstock paper 2 pages back from both front and rear cover. If there are any inserts present, place a sheet of 65 lb cardstock before and after each insert page. If there is a Mark Jeweler Insert with an adhesive backing strip for the mailer envelope, place a sheet of clean SRP Paper after the bottom centerfold backer board closest to the insert page.

10. Place bottom magazine sized backer board exterior layer on bottom steel plate.

11. Do not reuse backer boards with creases, staple dents, or dents present. Never reuse copy paper or cardstock paper. Backer boards may be reused, but only if there are no dents or warping present.

12. Place a sheet of cheap 20 lb copy paper on bottom backer board. The cheaper the brand, the better. Many premium high quality brands have now started to use OBA (Optical Brightening Agents) to their paper stock, which can cause a film or transference of these chemicals to comic books when damp or wet. We currently recommend Amazon Basics brand copy paper.

13. Special Instructions: If you are pressing a book with a stacking curl, or over 32 pages long, or a squarebound, place book with the most defects facing down first because you will flip the book and repeat the heat cycle to the other side after Step #20. Stacking curls should start with the bend facing up on the first press before the flip.

14. Place book with stacking layers in press machine. Spines should be positioned parallel to hinge or arm of machine. Book stack should be centered on plate.

15. Place top sheet of 20 lb copy paper on top of placed book with stacking layers.

16. Place top magazine sized backer board exterior layer on top of copy paper layer.

17. Place optional top plate on top of top exterior backer board, if you use one. I personally use a top plate to help keep all the stacking layers in place. Others find the top plate redundant.

18. Adjust pressure with your main hand if needed. Close press machine using off hand. This ensures that you don't accidently close the press machine using too much force and pressure. If you cannot close the machine using your off hand, you are using too much pressure.

19. Use an optional C-Clamp on the front edge of clamshell press machine if you have one. Using a C-Clamp will help make the downward pressure more centralized as opposed to being from the inside of hinge.

20. Leave heat cycle ON. Wait for the recommended duration of the heat cycle to complete.

21. Special Instructions: For thick books over 32 pages, squarebounds, giant size, or stacking curls, flip book to opposite side with the most defects facing up and repeat steps #3 - #20. You would also flip a book if there are a ton of defects present on both sides. If none of these conditions apply, leave the regular sized 32 page comic book inside press machine and do not flip.

22. Once the heat cycle is complete, turn OFF press machine. Do not open press machine right now. There must be a proper cool-down period or defects are guaranteed to return (reversion).

23. For vintage comic books and magazines with flat matte interior pages, wait 18-24 hours before removing book from press machine. For all books with thin glossy magazine style interior pages, wait 2-4 hours before removing book from press machine. Waiting is equally important as the press itself in order to produce the best results.

24. Books are typically done the next day. Keep pressed books in the same room as the pressing room environment for at least 5-7 days. Perform a reversion inspection check and take new photos. Compare results. After 7 days, the book can be safely shipped off to a third-party grading company or client.

Post-Press Storage Guidelines
After pressing, the paper fibers of a comic are in a “reset” state. They’ve been relaxed and flattened by heat and pressure, but they need time in a stable environment to fully settle. If you rush a book straight to grading or toss it back into an unstable storage space, you risk defects slowly returning.

• Cooling/Settling Period: Let your freshly pressed book rest for at least 24–48 hours in a controlled environment before bagging and boarding. This allows the paper fibers to stabilize naturally at room conditions. Some advanced pressers give high-value books a full 3–5 days before handling or shipping.

• Environment: Keep the book in a 70–75°F room with 40–50% RH (same as your pressing setup). Avoid humid basements, hot attics, or rooms with fluctuating air conditions. Stability is the key to preventing reversion.

• Flat, Supported Storage: Store the comic flat between clean, dry backing boards (no pressure, just support) or inside a bag and board with a full-size backer. Some collectors stack a light, even weight (like another flat board) on top to encourage the book to stay flat while it settles.

• Avoid Immediate Shipment: Mailing right after pressing is risky — comics can be exposed to heat, humidity, or pressure during transit, which may undo your work. Waiting a few days before packaging helps the fibers “remember” their pressed state.

• Longer Holds for Problem Books: If the comic had severe waves, stacking curls, or stubborn dents, give it a bit more rest — up to a week — before grading. Patience here means better long-term results.

• Always ship in stable climate: Avoid mailing during extreme hot or humid weather if possible.

REVERSION AFTER PRESSING
Another important concept is reversion — this happens when a book looks great right after pressing but slowly begins to “bounce back” to its previous shape. Reversion is often caused by pressing in unstable conditions where the temperature or humidity fluctuates. A consistent environment ensures that when the fibers are reset during pressing, they stay that way. Leave all vintage comic books (1930-2001) inside press machine until the next day before removing. Flaring, lifting, and wavy pages can develop when a book is removed too soon or improperly stored. While rare, reversion can (and does) happen. Review and verify the comic book retained a good press after 5-7 days. Keep pressed books in the same pressing room environment. I recommend this step especially if you are pressing a book for a client, friend, or a grading company! It is entirely possible to come back several weeks later - only to find your hard work performed on the book has reverted back to its previous state. Some books can be stubborn.

YOUTUBE TUTORIAL VIDEO PLAYLIST
I recently started some tutorial videos that illustrate different methods and techniques covered on this page. The videos do not have audio or sound and are shot with a gopro camera in 1080p. I don't want to be that guy, but they take a really long time to produce and edit so, "Please give a like and subscribe" Thanks!

ADVANCED PRESSING METHODS
You have read my free guide which covers everything you need to know in order to get started pressing comics. However, there are many advanced topics and advanced methods not covered in this free online guide. What about restoration detection or how to press squarebound prestige format comics? Comic Book CPR answers all of those questions and more.

COMIC BOOK CPR: SECOND EDITION
Comic Book CPR: Second Edition is a 250-page full color illustrated guidebook featuring pictorials and detailed procedures for cleaning and pressing comic books. Written by Michael Frederik Sorensen and Gregory Defoor, this all-new version of the previous title features a radically different way of pressing comic books safely and reliably, with consistent results every time. Say goodbye to wavy oversaturated books! You will no longer place comic books inside a humidity tank. Learn about underlay sheets and how to utilize them for maximum pressing potential with guaranteed results. The new three step pressing procedure is the core pressing method now with several variables to choose from. Books that were traditionally thought to be a "lost cause" are now possible in this new edition of Comic Book CPR. Subscription creased comics, polybagged comics, holofoil comics, thick embossed cardstock cover comics, and oversaturated heavily rippled comics are now easily pressed without a concern. This new edition features an updated Flow Chart and Inspection Forms to guide you through the new procedures. Learn the importance of your pressing room environment, and how it impacts reversion. This book is guaranteed to help you produce flat straight edges every time. PRESS ON!

COMIC BOOK SRW: SECOND EDITION
Comic Book SRW: Second Edition is a 270-page full-color illustrated guidebook featuring pictorials and detailed procedures for the stain removal and whitening of all comic books. This second edition contains updated corrections and modifications from industry experts in the field of comic book conservation. This illustrated guide is only intended for advanced users who are familiar with pressing comic books and fixing advanced defects. The authors of this guide have dedicated countless hours into testing each method outlined to ensure safe and proven techniques that are guaranteed to work! There is no disassembly required when performing the procedures in this guide. Learn about the mind-blowing method of using a light box to whiten and brighten your old comic book covers and interior pages through a process called photobleaching. Discover a brand-new way to use your existing press machine to remove foxing, tanning, and tide lines from comic book covers. Learn about a radical new way to remove stains using overlay sheets that will revitalize your comic books. This new edition features an updated Flow Chart and all-new Stain Matrix Diagrams to guide you through the advanced procedures. Each stain removal method now has its own chapter with full pictorials and procedures.

CGC COMICS
The author is also an authorized and licensed CGC Dealer. Have peace and mind the advice given on this website will help you achieve the absolute highest grades possible with CGC. CGC is the most trusted authority on third party grading of comic books since 2000.

JOIN US
There is a dedicated Facebook Group called "KaptainMyke Comic Book Pressing" for anyone to join and contribute ideas open for discussion. Ask questions about this guide or show off your own books! Anyone is welcome to join. I firmly believe the spread of accurate free information will help us all keep books preserved and conserved. You may find the Facebook Group at this link here:

CONCLUSION
The overall goal of this guide is simple: Press books in a manner so that others cannot detect the book has been pressed. Light pressure, not firm or hard pressure. Do not burn the book, do not pop the staples, and do not spin the books on surfaces. For temperatures, 150-160 degrees or lower seems to be the “sweet spot” on most books to play it safe. Pressing under high heat for less than 5-7 minutes on each side is good for most books. Keep moisture and humidity to a minimum on your books. Always keep a timer with you and don’t forget to set your timer! These steps are some of the things that can be done to successfully press a comic book, magazine, or poster with minimal to no damage to the item being pressed.

These tips will hopefully save you money, and guide you along the way as YOU learn and pick up new ideas and better ways to accomplish things. I am not a professional presser, and I’m not a professional grader. However, these are the methods I use when I press comic books as a hobbyist.

All of this is a learning process. I encourage you all to share your ideas among everyone so that we can all prevent damage to one another’s books. I am open to any feedback and suggestions. I also reside in a coastal Northwestern state, which is more humid than inland states. Your results may vary based on humidity and temperature of the climate you reside in.

HOW TO CLEAN and PRESS COMIC BOOKS