Gunpla Water Decals: Bandai's 8 Steps, Then a $5 Softener

If you buy one thing for your first Gunpla water decals, make it tweezers, not a bottle. Bandai's own Gundam Base guide gets a decal on with water, about 10 seconds of soaking, tweezers and a cotton swab. A $5 decal softener earns its place later, on curves and molded detail, and only in small doses.

TL;DR: A water decal is printed film on backing paper: soak it, slide it off, press it down. Bandai's Gundam Base blog soaks a Gundam Decal for about 10 seconds and finishes with a cotton swab. Mr. Mark Softer and Mr. Mark Setter were $5.00 each at Gundam Planet and USA Gundam Store. Check the kit's contents line first: a "seal" is a sticker, not a water decal. One builder soaked a kit sheet for about an hour, then thought it might be a clear sticker. Checked Oct 17, 2026.

Gunpla water decals? (quick answer)

Gunpla water decals are thin markings printed on a film that floats free of its backing paper once wet. Bandai's method needs no chemicals: wipe the part, soak the decal about 10 seconds, slide it into place, press out the water with a cotton swab and let it dry. Start there. Add Mr. Mark Softer ($5.00 at both big US shops) only when a decal won't settle over a curve.

Key Takeaways

• Read the contents line. Bandai's item pages list a "Foil seal" (a sticker) and a "Waterslide Decal" as separate items.
• Bandai's method: eight steps, about 10 seconds in water or lukewarm water, tweezers, cotton swab, then dry.
• Softener goes over, setter goes under. That is how GSI Creos describes Mr. Mark Softer and Mr. Mark Setter.
• Both bottles were $5.00 at Gundam Planet and USA Gundam Store on Oct 17.
• Gundam Decal sheets from No.141 onward run ¥550 to ¥1,430 with tax in Japan, and seven old ¥440 sheets return at ¥770 in the January to March 2027 reissue.

Overview: water decal, sticker or "realistic decal"?

The word "decal" covers more than one thing on a Gunpla box. Bandai's item pages keep them apart. The MG Wing Gundam Zero EW Ver.Ka page, for example, lists a "Foil seal × 1" and a "Waterslide Decal × 1" on separate lines. The foil seal is a sticker. The waterslide decal is the kind this guide covers: a film you release with water.

Bandai also sells water decals on their own. Its Gundam Decal line has numbered sheets for specific kits and multi-use sheets for a whole series. The Gundam Base staff blog explains the idea: a Gundam Decal turns the markings that come with the matching kit into water-transfer decals, thinner and with less margin than the stickers or decals in the box (our translation). The blog adds that you can use them on other kits too.

A Bandai marking sheet from the RG Zaku II, labeled リアリスティックデカール (realistic decal). Check each kit's contents line for the type. Photo: Gravis / Wikimedia Commons, CC BY-SA 4.0.

Some kits ship with water decals already. Two Ver.Ka kits we checked do, the Wing Gundam Zero EW and the Zeta, and the Zeta Gundam Ver.Ka page says its waterslide decal was designed by Hajime Katoki. Our Gunpla Ver.Ka guide lists which Ver.Ka pages mention one.

Desk note: Our copy of Bandai's Japanese list has 167 Gundam Decal items. Twelve new sheets, No.144 to No.155, are dated January to March 2027: as many Gundam Decal items as Bandai's list shows for all of 2021. Six are kit-specific sheets at ¥770 with tax. The other six are multi-use HG sheets at ¥1,430, 2.6 times the ¥550 of the 2025 SEED FREEDOM sheet No.142.

Diagram: PlamoDesk. Sources: Bandai Hobby Site (Japan) item pages and reissue price notice.

Step-by-Step: Bandai's method for Gunpla water decals

This is the order from THE GUNDAM BASE TOKYO staff blog, our translation and summary. It is written for Gundam Decals and uses no decal solution at all.

Diagram: PlamoDesk. Source: THE GUNDAM BASE TOKYO blog (December 2021), our translation.

1. Clean the part. The blog's first warning: wipe oil and dust off the part before you apply anything.

2. Cut the decal out with its paper. Use scissors, a hobby knife or a design knife, and cut through the backing paper, not just the film.

3. Soak about 10 seconds. Water, or lukewarm water.

4. Rest it on something absorbent. Kitchen paper or a sponge draws off the extra water.

5. Wait until it moves. When the decal slides on its paper, hold the paper with tweezers.

6. Slide it off next to the spot. Slide the decal off its paper close to where it goes, then place it.

7. Nudge it into place. Use tweezers or a toothpick, gently.

8. Press out the water and dry. Use a cotton swab to take off the extra water and press the decal onto the part, then let it dry well.

Tamiya's instructions for Mark Fit add a bottle to the same routine: apply Mark Fit where the decal goes, place the decal, press out the water with a soft cloth or cotton swab, apply more Mark Fit over it, press again and let it dry completely.

GODEEPER: Still choosing your first tools? Gunpla tools for beginners →

Decal softener vs setter: when a $5 bottle helps

Use a softener when a decal sits on a curve or molded detail and won't lie flat. Use a setter when an old or weak decal won't stick. All three bottles in the table are 40 ml, and on Oct 17 they cost $5.00 to $6.00 at Gundam Planet. The cost is small; the risk is using too much.

Diagram: PlamoDesk. Sources: GSI Creos Mr. Hobby and Tamiya product pages; Gundam Planet and USA Gundam Store, Oct 17.

Mr. Mark Softer (MS231). GSI Creos calls it a decal softener for molded surfaces, curves and hard decals, applied over a decal already in place (our translation). The maker warns it softens fast. Too much can melt or tear the decal or attack the paint underneath. It is water-soluble, and the page gives about 10% as a dilution guide.

Mr. Mark Setter (MS232). A decal glue. GSI Creos says to put a little where the decal goes and lay the decal on top, and that it works best on old decals or ones with weak adhesive. It also contains a softening ingredient. The dilution guide is about 30%.

Tamiya Mark Fit (87102). Tamiya says it "softens decals so they can easily fit to uneven, rounded, and matt finish surfaces". Its Strong version "May cause damage to painted surface in some cases, particularly surfaces painted with acrylic paints."

Silvering is the name for air trapped under a decal. GSI Creos describes the fix: once the decal is dry, prick it carefully with a needle or design knife, then apply Mark Softer again so the decal softens and settles. The same page says a glossy surface under the decal is one way to prevent it.

US prices on Oct 17:

Five dollars a bottle, and the maker's main warning is to use less of it.

Tips

• Find out what you have before you soak. Read the kit's item page: Bandai lists a "seal" (a sticker) and a "Waterslide Decal" as different items.
• Buy the sheet for your kit, or a multi-use one. Gundam Decal numbers name the kit they match, such as No.147 for the RG RX-78-2 Ver.2.0. The Gundam Base blog notes that its RG sheet worked on a BB Senshi kit as well.
• Multi-use sheets cost more in the US too. USA Gundam Store had the ¥1,430 multi-use sheet No.154 at $15.99 and the ¥770 sheet No.153 at $8.99, both as Q2 2027 preorders.
• 30 Minutes Missions has its own sheets. The 30MM water decal multi-use 5 is ¥660 with tax in Japan, dated Oct 24. Gundam Planet listed it at $6.95 as a preorder for November 2026; our 30 Minutes Missions guide covers the line.
• Plan the top coat around the decals. GSI Creos says a glossy surface under a decal is one way to prevent silvering, and describes coating applied decals with gloss clear. Our Gunpla top coat guide covers matte sprays over decals.

What builders say

From a 2016 comment thread under Gunpla 101's post on applying waterslide decals with a modeling tray:

• Fikko3107 (August 2016), after an HG build: "it does not seem to soak in completely even after an hour of so of waiting."
• TheInnerGeek (August 2016), replying: "Does this HG kit even come with water slide decals? Is it possible these were dry rub decals you were soaking?"

The builder later wrote that the sheet may be like the clear stickers in an RG kit. One hour, one dish, and quite possibly a sticker. The contents line on the item page would have settled it in a minute.

On the softener side, a Gundam Planet reviewer of Mr. Mark Softer, Seth P. (April 2019), titled his review "BE CAREFUL": "This will completely destroy decals if you’re not careful. Do it right by dabbing a cue tip over the decal instead of rolling it over." That matches the maker's own warning.

GODEEPER: Wondering which grades ship with decals and which with stickers? HG vs RG vs MG →

Our take

Start with water, tweezers and a cotton swab; buy Mr. Mark Softer only when a decal fights a curve. Bandai's own eight-step method uses no solution at all. The softener costs $5.00 at both big US shops, and its maker warns that too much melts decals and attacks paint. If you plan to apply many decals over panel detail, buy the Softer and the Setter together; the pair was $10 at Gundam Planet. We recheck prices when the January 2027 Gundam Decal sheets reach US shops.

What we don't know yet

Bandai's English site has no decal how-to page that we could find, so the method above comes from a Japanese staff blog of December 2021. US arrival months for the 2027 sheets were only given as quarters.

How we checked this

On Oct 17 we read the Gundam Base staff blog's Gundam Decal guide, GSI Creos's Japanese pages for Mr. Mark Softer and Mr. Mark Setter, Mr. Hobby Europe's English pages for the same bottles, and Tamiya's Mark Fit pages. Bandai's Japanese and English item pages gave the decal types and prices; the Gundam Decal count comes from our copy of Bandai's Japanese list (Oct 11), and reissue prices from Bandai's price notice. US prices come from Gundam Planet and USA Gundam Store searches with sold-out items shown. We haven't used these products ourselves.

Frequently Asked Questions

How do you apply water decals to Gunpla? Bandai's Gundam Base blog gives eight steps: wipe the part, cut the decal out with its paper, soak it about 10 seconds in water or lukewarm water, rest it on kitchen paper, slide it into place, nudge it with tweezers, press out the water with a cotton swab and let it dry.

How long do you soak Gunpla water decals? About 10 seconds in water or lukewarm water, according to the Gundam Base staff blog's guide to Gundam Decals. Then the decal rests on kitchen paper until it moves freely on its backing paper. If it still will not move after a long soak, check the kit's contents line: Bandai lists a seal (a sticker) and a waterslide decal as different items.

Do I need decal softener for Gunpla? Not for a first decal on a flat part: Bandai's own eight-step method uses only water, tweezers and a cotton swab. GSI Creos sells Mr. Mark Softer for decals on curves and molded detail, and warns that too much can melt the decal or attack paint. It was $5.00 at Gundam Planet and USA Gundam Store on Oct 17.

What is the difference between Mr. Mark Softer and Mr. Mark Setter? Placement and job. GSI Creos calls Mr. Mark Softer a decal softener that goes over a decal already in place, diluted about 10%. Mr. Mark Setter is a decal glue that goes under the decal, for old or weakly adhesive decals, diluted about 30%. Both were $5.00 at Gundam Planet on Oct 17.

Are Gundam Decals water slide or dry transfer? Water slide, on the Bandai pages we read. The No.1 sheet of 2005 is listed as 水転写式デカール (water-transfer decal), and the English pages for Gundam Decal 142 and 143 list a waterslide decal sheet. Bandai's Japanese list has 167 Gundam Decal items, from ¥440 to ¥1,430 with tax for the general-release sheets.

Related Reading

• Gunpla Tools Guide: the full tool hub, from nippers to tweezers and decal aids.
• Where to Buy Gunpla in the US: shops, exporters and preorder terms.
• Gunpla Grades Explained: which grades ship with stickers and which with decals.

References

• THE GUNDAM BASE TOKYO blog: 水転写デカールチャレンジ講座 (December 17, 2021)
• GSI Creos Mr. Hobby: Mr. Mark Softer MS231, Mr. Mark Setter MS232; Mr. Hobby Europe: Mr. Mark Softer, Mr. Mark Setter
• Tamiya: Mark Fit 87102, Mark Fit (Strong) 87135
• Bandai Hobby Site (Japan): Gundam Decal brand page, Gundam Decal No.1, No.142, No.144, No.147, 30MM water decal multi-use 5, reissue price notice
• Bandai Hobby Site (English): Gundam Decal brand page, MG Wing Gundam Zero EW Ver.Ka, MG Zeta Gundam Ver.Ka
• Gundam Planet: Mr. Mark Softer 40ml, Mr. Mark Setter 40ml, Mark Fit
• USA Gundam Store: MS231 Mr Mark Softer, Gundam Decal 154
• Gunpla 101: applying waterslide decals with a modeling tray, comments
• Wikimedia Commons: Gunpla decal sheet (Gravis, CC BY-SA 4.0)