Sculpting with Epoxy Putty
By Andrea Daley

 

(The following is an in-depth process of how to sculpt missing parts, attach them and glaze them. The same process can be applied to furniture and wood carving parts that are missing. The article is long but needs to be, so all steps are covered.)

Making small intricate parts for figurines is not as difficult as one may think! So often, high valued items such as Meissen figurines or collectibles such as Lladros, Hummels or any art pottery or porcelain that has detailed protruding parts will get broken or chipped. In many cases the parts become lost. Duplicating these missing parts is a process of hand sculpting and then knowing a few "tricks of the trade" to attach them.

The substance I use to sculpt these parts is called Plumbers Seal. I also use it as my main filler. It’s an "odd" name for creating some of the finest work on some of the finest porcelains! Among all the sculpting putties, I find this one to have the most versatility. Plumbers Seal was first intended for exactly its name, for the plumber. It is two-part epoxy putty that plumbers use. When it is properly mixed, it can be placed in an area that may have a leak. It has adhesion properties and cures under water. When it is cured it is as hard as a rock. Most Home Depots (in the pool section), plumbing supply stores and some hardware stores carry this product. If you are having problems locating it, you can call the company, Atlas Mineral Company (1-800-523-8269), and they can either sell it directly to you or advise you of their nearest store. Today it is widely used among the restoration of porcelain and pottery.

I started using this Plumbers Seal well over 25 years ago. It has become my choice for filling in chips and cracks as well as sculpting parts. There are other epoxy putties. Milliput, which is located in many hobby shops, is similar to Plumbers Seal. It can be purchased in white. I sometimes use this for filling in chips. It does not have the flexibility for sculpting as Plumbers Seal. Quick Wood and some of the fast setting epoxies just do not work when time is needed to hand sculpt. All these have the tendency to crack or break when making parts. Plumbers Seal has a window of approximately 45 minutes of working time. This working time allows the artist to recreate some of the smallest parts; the little roses on a Lladro, a missing finger, the reins of a horse on a Meissen figurine, stems and flowers, a bird or missing bow on a Hummel; any object no matter what size or shape. Within minutes a new piece can be sculpted to the exact thickness and form.

It is very important to properly mix the substance. If it is not thoroughly mixed it will not become hard. People have a tendency to under-mix. I see this time and time again when I have taught group classes. There will always be someone’s filler that did not get hard. The reason is because it was not mixed thoroughly. It comes in two parts, A and B. I place equal amounts between my thumb and first two fingers. Using both hands, I then begin to knead and mix. Just keep doing this until it starts to become real sticky. It will start to stick to your fingers. Just keep kneading some more. When you think it has been long enough, then do it some more. It is real important that it gets mixed. It will turn uniform in color. By now you have a sticky mess on your hands. For large amounts I use both hands; using the thumb of one and the palm of the other. Again you will end up with it sticking to both hands. Use a Popsicle stick or an artist’s knife to remove the substance from your hands or fingers. Do not go to the sink to wash off the remaining part. It will take longer and like plaster or other substance that has an adhering ability, it may after prolonged use clog your pipes. The quickest and easiest way is to dip a cloth in water and transfer the substance from your hands to the cloth. The Plumbers Seal is not dissolvable in water, so it takes pressure to remove it. Make sure all of the substance is off your hands. Check around and under your fingernails. The next recurring problem that shows up with the student is the permanent fingerprints that end up on their items. It never fails; someone did not take the time to remove all the substance from his or her hands. It then gets left on the item as a permanent fingerprint. This substance is difficult to remove and in some cases impossible with out doing damage to the item. This is especially true on gold sections. Once it has cured, just the rubbing to remove it will also remove the gold. So it is very important that your hands are thoroughly cleaned. Not only at this point but all the way through the process.

It is important to understand what is happening when epoxy is mixed. As soon as it is combined a chemical reaction takes place. Like all epoxies, they have a curing time, not a drying time. Materials that have drying times will shrink. That is one of the reasons this product is my choice. There will be no shrinkage or pulling away after long periods of times.

There are different functions that can be performed at the different stages of its curing time. Under normal conditions, indoors, 70 degrees, it will take anywhere from 8 to 10 hours to cure. (To reach its hard rock state) Meanwhile, within the first hour of its set, certain applications can be made. Within the first 15 to 20 minutes of its cure, any areas that need to be filled: chips, cracks, holes or any little missing sections can be easily accomplished. At this stage it has its best adhering properties. Once it starts to set up, it can no longer be used for filling in these sections. It will start to roll, or not stay where you place it. Instead of struggling with it, I just put it aside and make up some more. Keep in mind that you need to be continuously cleaning your fingers to prevent permanent fingerprints on your item. Remember that water does not dissolve the substance. A damp cloth will transfer it to the cloth. I use water to smooth out the filled areas. Bring the filler just up to the edge of its placement. Dip your finger in water and rub over to smooth. I also do this with my Exacto knife. I have dulled the sharp end so it is smooth. I use this for applying the filler to the desired section. I dip it in water and then scrape over the fill. This is how I apply the filler to small sections or cracks. I take a small amount on the end of the knife and force it with pressure into the crack. It is better to do two or three fills to bring it level rather than having it high and then sand. Sanding takes much longer. This is something that you will learn by doing. After a few times of over filling you will soon realize this point. Another important part of the process is to keep cleaning around the area after you have smoothed it with water. If any of the water has the putty in it and has become a run or drip, then if it is not cleaned with water at this point, it will dry as hard as the finger prints and again will be difficult to remove. (More detail and techniques will be addressed in another article on the subject of filling)

After approximately 30 to 40 minutes you can start sculpting different parts. If it has not started to stiffen, it may need another 10 minutes of curing time. On warm days and if you are working out doors, it will harden much quicker. Also, different sets of the Plumbers Seal may slightly vary on their curing time. Once you recognize its set you can begin to sculpt. There is a window of about 45 minutes to sculpt parts, after that it starts to get hard and will crack. If you coat your hands with Vaseline or some type of oil, it will allow you to work without it sticking to your fingers. Since I use Pam with my mold making process and it is accessible to me; I just spray it onto my hands. The surface from where you are working also needs to be coated. Again, just a quick spray of Pam across a paper plate, will do. I use grease resistant paper plates for all my processes in restoration. They are disposable and have a white background so they also become my palettes for my paints. Make sure "grease resistant" plates are purchased. The ones that are not will allow paints or oils to soak right through them.

The following are the methods for sculpting small parts.

A finger

Flowers

To make a Morning Glory, start with a round ball, flatten it to the thickness of the desired flower, and then lay it over a prepared shape. Take a piece of Plasticine modeling clay and with the wooden end of a round paintbrush, poke a hole into the clay and taper the edges. Lay the flattened out putty, (being slightly larger than the hole), over the form. After it is positioned, take the paintbrush end and poke the putty into the shape of the hole. It will create a perfect Morning Glory as you see on so many Meissen pieces.

Dandelions

Leaves

Ribbons and Reins

Just remember that during the process, grease and oil was added to the parts that were made. Before reattaching any part, clean them with lacquer thinner or acetone. If all grease and oils are not removed, then the paints and other chemicals will not stick properly to the restored area.

Once any part has been made and cured in position the next step is to break it off and re-attach. In regards to attaching a finger, undercuts need to be made. (See article on undercuts). This will create an area where the filler will become trapped, which will create a stronger bond. In addition to the undercuts a channel is made on both ends where these ends are to be attached. The drilling of such delicate areas needs to be done with diamond point bits. These bits can be purchased through a Lapidary (Gem) supply store. If you have problems locating these parts, then let the Association of Restorers know and we will forward you a mail order address.

Once prepared as the above diagram shows, position it in place by balancing it in a sandbox or add a piece of clay, formed to the correct shape, to hold it in place. Once positioned, adhere it by using epoxy glue. I use five-minute. The general theory is, the longer the curing time the stronger the bond. Once the section has cured then come in with the two-part epoxy filler, and fill in the channeled areas forcing the putty into the undercuts. It will take a knack to level the filler with the parts being joined. I use my Exacto knife with water to smooth over and even out any excess. Sometimes I dip a paintbrush into water and smooth over any hard to reach areas. Once cured, use 400 grit sandpaper rolled on the end of a toothpick. There now is a sticky backed paper that works just perfect to sand out these delicate areas. Sand in and around to make completely level. Just be careful not to place an excessive amount of pressure. You may be back to square one. I tell my customers that I do not guarantee fingers or any small protruding parts. Even though all these steps are taken, any mishandling or pressure on these parts will snap them off. When transporting these parts special packaging needs to be done (another topic).

When attaching flowers, leaves, ribbons or reins, a special process is preformed. Once positioned, a coat of epoxy resin is applied. I suggest for the inexperienced person to start with the 1 hour curing epoxy adhesives. This will give you plenty of time to clean your brush. First thing that needs to be done is to make sure the parts you will be coating will not react with the epoxy glue. If there are any oils on these sections, then fish eyeing will appear. This information is very critical. Two things can happen. If you do not clean your paintbrush thoroughly, it will be of no use. Second, if this step is not executed to perfection, then all is lost up to this point. You will need to start over recreating the part. Follow the steps carefully. Mix the epoxy glue thoroughly. Epoxies will draw moisture into it by using a wooden Popsicle stick and paper plate. This moisture creates bubbles and may get trapped in the coating itself. This would create an uneven finish. Never mix the epoxy on grease resistant plates. It picks up the grease from these plates; it goes into its mixture and then it will separate and leave funny looking texture in the finish. Use a glass surface and a metal rod. Use paper towels and lacquer for clean up. After it is mixed, use a good grade paintbrush. The size of the paintbrush needs to be in relation to the part being epoxy glazed. You may want the part to be warm. Heat the part up under a heat lamp for about 5 minutes. This will allow the epoxy to flow more evenly and be of a thinner consistency. If you wish the epoxy to be heavier, then omit this step. Work quickly, coating all the parts that were made. Be thorough with the coating not to miss any parts. A break in the epoxy will show up when being painted. Then, correcting the finish at that point will be difficult. Practice all these steps several times on an object of no value before proceeding on a customer’s piece.

It is very important that the epoxy flows on smoothly, does not accumulate in crevices and is blended to a stop point. A stop point is where the epoxy ends. If it is in the middle of a smooth flat section then a technique to eliminate this raised area needs to be preformed. This process may be performed by either using a paintbrush or your finger. Take a paintbrush dipped in lacquer thinner, and brush the ending edges by smoothing and tapering them into the existing finish. Or take your finger and smooth out the end area by dipping your finger in the lacquer thinner and pressing lightly over the edge area and then finishing off with more intense pressure to create an even effect.

For all the created parts, the stop points would be at the end of the parts. This epoxy glazing process will also add strength to the parts.

Immediately after coating these parts, take an aerosol can of spray lacquer, (I use Mohawk Finishing Products water clear gloss) and spray the areas you just coated. This will release all the air bubbles and moisture that may have been trapped in the finish and will make it flow together evenly. Like magic you will see a perfectly smooth finish, surface before your eyes.

Once all these areas have cured, the next step is to white them out with an airbrush. Keep in mind that over time the epoxies turn a deep yellow. They will not have the yellow color now, so the item must be thoroughly whited out before painting. The only time I do not white out is, if the color is going to be dark, yellow or painted gold.

Future articles will written be on painting and different techniques to create effects. (See Airbrush course on the Internet.)

If anyone has any questions on this process or any processes regarding restoration of either porcelain/pottery, glass, furniture, gold leaf, photo/paper, silver, other metal, glass or any other subject, please post it on the Q&A Forum of your website.

– This time take a larger piece of pre-mixed, partially cured putty and again roll it into a snake shape. The amount needs to be approximately 3 inches long and approximately ½ inch in circumference. Then spray with Pam and take a small doll’s rolling pin or a glass jar and roll the section out to the thickness of the ribbon or rein that needs to be replaced. (It is easier to remove all the existing parts that are damaged, rather than attempting to patch and attach it partially to the damaged section.) Take a sharp razor blade and cut the ribbon or rein to the size needed. Then just drape it or place it into the desired area. Since it is so thin, in most cases you will need to prepare the shape of its placement by first setting clay in place so the ribbon or reins can be draped over the clay which will hold it out from the piece. – Hand cut to the desired shape, add the ragged edges by using a knife and then shape into the desired position. Leaf metal templates and flower templates can be purchased at ceramic shops. (found on Boehm porcelains) – Roll out a section larger than 6 inches by ¾ inch. Then with a razor blade cut it to an even rectangular shape. Proceed with the razor blade to make cuttings as if making grass as we use to do in school, being careful not to go all the way through. Then roll up and pinch off at the bottom to hold. Adjust the petals to the desired shape. Once cured you may need to add a stem and leaves. - (Rose) start with rolling out approximately 12 to 15 small balls. Then flatten each out to a circular shape. Use plenty of grease resistance so it will not stick to your fingers or the tool used to make them flat. Sometimes I use the flat end of a dowel, but most of the time my only tool is my fingers and my Exacto knife. Once rolled out, take the first one and roll tight, followed by two more placed closely to form the center of the rose. Next, start adding the petals as a rose appears. You may just need to take a real rose apart to see how nature arranges its petals. Just copy, you can add the little dips in the middle of each petal or create a jagged edge by pinching it off. As long as the putty has not gotten too stiff, the petals should stick by themselves. If not, then a drop of CA adhesive on the end of a tooth pick will hold each petal in place. Sometimes I work from the end of a toothpick for an anchoring point and to give it support, especially if they are little flowers. Other flowers are started the same way. – Roll out a snake the width of the finger to be replaced. You know how to do the snake; with in your first 5 years of childhood, you made many. So the talent is already there. Cut it a little longer that the one replacing. Hold it between your index finger and thumb and with the tip of your other index finger just slightly pat the end to form the same shape that as the ones to be matched. Oriental fingers are long and pointed, Meissen fingers have great detail in them, (nails, knuckles), Lladro fingers are long and rounded. Just copy whatever the existing fingers look like. If the putty is too soft, it will not hold its shape, so you will need to wait a little longer. You will know when it is pliable to work with. After getting the end shaped, if it needs to have detail, take the Exacto knife (dull rounded off end) and just slightly press the tip into the putty end to form the finger tip. There is the mark for the length of the nail and the two sides. Three little marks and you have a fingernail. Next add the knuckle by just laying the knife blade perpendicular, judging where the knuckles would be and pressing a line into the putty from underneath. Once you have the shape formed the rest will come naturally. Once the finger is created, I transfer the end of the finger where it is to be attached to the area where it is missing. This needs a delicate touch. With pressure, transfer the putty end to the broken area. It usually will stick for me, but if you are unfamiliar with this process, you will just need to make several attempts. Of course the longer it takes you to join it to the piece the more chance of messing the end up. If so, just make another one and start over. Very seldom do I get everyone perfect on the first attempt. Once in place, do not worry about the strength of the hold, all you are doing at this point is getting the length and position aligned. The next thing to do is balance the item so the part does not droop or change shape. Once in place, let it cure. To hasten the curing time, place the item under a heating lamp. A heating lamp, set up on an expandable arm, is part of my basic equipment. I am always using the heat lamp for either drying out paints, curing the two part epoxy, or just keeping warm in the Northeast. While working in humid weather, sometimes the sandpaper gets soft. Just place it under a heat lamp for a few seconds and it will be crisp again. (Just a couple of extra tips)