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As more and more new products come onto the market ‘traditional’ modellers fi nd themselves needing to learn a whole new set of skills. First it was iron on covering, then brushless motors and now, from the Deluxe Materials stable, Eze Dope.The fi rst thing you have to realise about Eze Dope is that

it isn’t, in fact, dope at all. From my experience it can be used to do all the things cellulose dope will do, but there are certain differences in the way we use it and in the way it behaves in use. As with other innovations, once you have learned the required skill-set you’ll wonder why you ever used anything else.

As a modeller of long standing, I came up via the traditional route. After learning to build and cover rubber power models I progressed though powered free-fl ight, control-line and radio control. The one constant throughout this progression was the use of cellulose dope fi nished covering; right up until I discovered iron-on fi lm.

Now, as I revisit the type of models I built in my youth (shortly after the extinction of the dinosaur), I fi nd myself using tissue and dope fi nishes again – with a difference. Instead of brushing on coats of cellulose dope, with its’ attendant unpleasant smells and need for adequate ventilation, I use Eze Dope which has virtually no smell and allows me to sit comfortably in the house while I fi nish my models.

WHAT IS EZE DOPE?Although I don’t know the precise, technical specifi cations, it is a water-based polymer that both shrinks and toughens tissue covering. It can also be used on heavier coverings and for treating bare wood. Eze Dope can be thinned using plain water and either brushed or sprayed on in the same way you would with a

Covering the Eze Dope WayBy Peter Rake

Product Review

When covering with tissue, reaching for the cellulose dope has been the natural reaction of modellers for probably the past 100 years. But is there a better way?

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1: The West Wings Topaz kit and a selection of the products used to complete the build. 2: The plan pinned down and protected with waxed

side built using Aliphatic glue. 3: Still using just Aliphatic the tailplane takes shape. 4: All the basic structures sanded and ready for covering – once the wings are joined. 5: A naked Topaz,

Eze Dope. 6: 50% thinned Eze Dope is applied all round the outline and allowed to dry before proceeding with the covering.

cellulose fi nish. Unlike cellulose dope, once dry Eze Dope has the added

benefi t of being fuelproof.

HOW IS IT DIFFERENT?The most obvious difference is the lack of smell. Even holding the pot directly under your nose the only smell is a faint ammonia type odour. In use there is no noticeable

smell at all.Like cellulose dope, as it comes out of the

pot Eze Dope is relatively thick and should be thinned for use. However, in the case of Eze Dope, the thinner medium is nothing more technical than water, making it much cheaper to use.

In use the most apparent difference is the way in which it dries. Unlike cellulose dope

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simply washed clean.The slower drying time allows more time

for accurate alignment of panels around obstructions.

The same applies to getting a smoother, more even application of the fi nish.

It can be thinned to varying degrees to suit the chosen application and the thinner used is absolutely free. For brushing onto tissue and thinned 70% water to 30% Eze

Dope a single pot supplies enough for several models making it economical in use.

The level of gloss is easily controlled by the amount Eze Dope is thinned, and how many coats you apply.

Once dry an Eze Dope treated tissue fi nish is extremely stable. No more limp looking models if it’s a bit damp out when fl ying. I’ve even lightly steamed (held over a kettle spout) a test piece without the

tissue slackening off. A wet rag left on a wing for fi ve minutes resulted in very slight slackening, that had tightened up again by the time I’d carried the model from the kitchen to the dining room. – without the wing warping.

As far as I’m concerned, Eze Dope will be the fi nish of choice on my future tissue covered models.

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Product review

there is no evaporation of solvent. It dries more in the manner of a skinning resin – it sets rather than dries out. As such, you must take care to brush out the fi nish, exactly as you would when applying paint. If you don’t ‘lay-off ’ the brushed on Eze Dope any brush marks, spots of Eze Dope or thick areas will skin over, set and remain there. It doesn’t soften and brush out with subsequent coats like cellulose would.

You’ll very quickly notice that it is slower drying too, so brushing out isn’t a problem. You have plenty of time to ensure even, smooth coverage.

Despite these differences, Eze Dope can be used in exactly the same way as cellulose dope and all brushes just washed clean under the tap.

EZE DOPE IN USEFor the purposes of this review I chose the Topaz by West Wings, a lightweight rubber power model, as the test subject. It is covered using lightweight Esaki tissue that had

been printed using waterproof inks and applied wet. Throughout the test the object was to adhere as closely as possible to the techniques used for applying tissue using cellulose dope. Any points of interest will be noted in the relevant step of the process.

WHY EZE DOPE?There are many advantages to using Eze Dope in place of cellulose dope. Here are some I’ve found.

Although not relevant to the electric models I usually build, it dries fuel proof. Cellulose dope is quite badly affected by the nitro in glow fuel.

The lack of smell means I am able to cover in the house, rather than relying on the weather to be able to do doping outside. It’s very nice to be able to sit at the coffee table to do my doping without complaints about the smell.

All brushes and tools can be cleaned in water and spills are

Eze Dope is available from good model shops around the world and distributed by Ripmax in the UK and Horizon Hobby in the USA. One additional advantage of Eze Dope is that the lack of volatile components means it can be safely sent through the post if you do not have a local supplier. The water based nature of Eze Dope does differentiate it from cellulose dope and requires a little forethought; it is NOT suitable for airframes built with water soluble PVA type glues (aliphatic is OK), or tissue with no wet strength.

STEP 1

Apply a coat of Eze Dope around the outline of the panel you wish to cover and allow it to dry. The Eze Dope can either be applied straight from the pot, or thinned 50% with water. Neither seems to lift the grain as much as cellulose, so only minor sanding (if any) is required to obtain a smooth surface.Be aware that unthinned Eze Dope will leave brush marks unless care is taken and any droplets will harden into bumps. However, you have plenty of time to brush it out well.

STEP 2

Flop on the sheet of wetted (fl oat it on water) tissue. Take care only to use tissue that has wet strength.

STEP 3

Carefully tease out any wrinkles and align the tissue precisely as you would using any other fi nish.

STEP 4

Using Eze Dope thinned anything between 50% and 70% brush around the edge of the tissue panel, so the Eze Dope soaks through to the initial application. Unthinned Eze Dope is diffi cult to brush out suffi ciently without putting the covering at risk of moving or tearing. Thinning it as suggested allows it to brush out more easily and results in a smoother fi nish.

STEP 5

Use a fi ngertip to continually smooth down the tissue until the Eze Dope has a fi rm grip. Being slower drying it needs you to continue making sure the tissue is fi rmly attached to the framework. However, it also allows you to ‘fi ne tune’ the positioning of the tissue panel. This has proved particularly useful around such areas as where the landing gear wires protrude from the fuselage. The tissue could be repeatedly teased and smoothed until it fi tted perfectly.

STEP 6

Allow the tissue to dry out and water shrink before trimming the edges and lapping around the extremes of the frame. Apply more Eze Dope and repeat the fi nger smoothing to stick down the edges.Eze Dope works extremely well when applying small sections between other doped on areas...

STEP 7

Repeat until the entire model is covered. Eze Dope works extremely well when applying small sections between other doped on areas so joining panels of tissue is relatively trouble free.

STEP 8

Apply multiple coats of 70% thinned (30% Eze Dope/70% water) of Eze Dope, making sure to brush out each coat to achieve a smooth, droplet free fi nish. Allow each coat to dry between applications and, as more coats are applied, you will gradually develop a very attractive gloss fi nish. The level of gloss will depend on the number of coats applied and can be controlled precisely to your liking.

NoteThroughout the application to printed tissue check using a scrap piece

fi rst. On some waterproof inks the polymer in Eze Dope can soften that of the ink. So far I’ve only found that to happen when applied to dry

tissue on bare sheet balsa. It doesn’t appear to be an issue with wet tissue applied to open frame structures. It makes no sense to me but at least

you have been warned. If you do have this problem you are probably better advised to use

Deluxe Materials tissue paste to attach the tissue to your model.

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Top Tip On small models, with very thin tail surfaces, there is always the risk

that the two surfaces of tissue will touch when they sag as the Eze Dope is applied. This is also a problem using cellulose but can actually use Eze

Dope to avoid it. Instead of using water to wet the tissue before you apply it, use a 5% solution of Eze Dope. Apply the panel as above and once touch dry

weight down the surface to avoid warping. Repeat the process for the opposite side.

Now when you apply a coat of 70% thinned Eze Dope the pre-treatment means the tissue only slackens, instead of sagging, thereby

avoiding the two surfaces touching and sticking fi rmly together.

7: 8: The tissue is then teased out carefully until it is wrinkle free. 9: Take your time smoothing and aligning the tissue – without tearing it. 10: Once the tissue looks like this you’re ready to begin sticking it in place. 11: More 50% thinned Eze Dope is applied to the edges of the still wet tissue. 12: Keep brushing on the thinned Eze Dope until you are sure it penetrated all the way around the frame being covered. 13:14: Once the tissue has water shrunk use a really sharp blade to trim the edges, followed by another coat of 50% thinned Eze Dope on any edges that aren’t stuck down. 15: 16: Once all the edges are stuck

17: It is important to brush out the 70% thinned Eze Dope evenly, ensuring there are no puddles or droplets formed in the wrinkles of the slackened tissue. 18: Eze Dope’s slower drying time means getting wet tissue accurately smoothed out in awkward places is no longer a nightmare. 19: You can even use Eze Dope to apply tissue over acetate screens, neatly hiding the untidiness inside – without melting the acetate.

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