FAQs

Below are a series of questions. 


Our Service FAQ
Can I add to my order?

You can add to your order with in two hours of placing it. As long as this falls before the 15:00 cut off time. An added delivery charge may be incurred, if the addition take the order up into the next delivery weight bracket.

Who will deliver my order and can I track it?

Orders under 2kg delivered to the UK are sent by Royal Mail and cannot be tracked.  Orders over this weight are sent by our courier, A.P.C, and are trackable. A tracking code will be supllied in a conformation e-mail, sent after an order has been successfully dispatched.  For more information on our delivery, click here.

When will my order be dispatched?

We aim to get all orders placed before 15:00 dispatched the same day. If however, an item is our of stock we will contact you immediately, offering an alternative or a refund. A reply is required before 15:00 to guarantee same day dispatch. If an order requires specialist picking and packing, e.g palletised deliveries, or large volume orders, we cannot guarantee same day dispatch, and would recommend if such an order is urgent, to contact us, to discuss the delivery options.

How do I go about returning an order?

In the unlikely event that a parcel arrives damaged or faulty please contact us on 01761 411077(Monday to Friday 9am to 5pm) or by email at sales@bathpotters.co.uk so we can arrange a replacement, exchange, or refund for you.If you wish to return an item, with the exception of personalised products, we need to receive it back into our warehouse within twenty eight days of receipt for a refund or exchange. Please retain all packaging until you are sure you wish to keep your items. Should you wish to return an item to us please repack it with care using all original packaging or a suitable alternative. This does not affect your statutory rights. This does not affect your statutory rights. As the goods are your responsibility until they reach our warehouse please ensure you package your return to prevent any damage to the items or boxes.With the exception of faulty and damaged goods we are not responsible for the return postage and do advise that you obtain a certificate of postage and insurance in case the parcel fails to reach us.If an item is returned to us outside of the twenty eight day time frame or is in a non re saleable condition a credit note will be issued at the discretion of Bath Potters Supplies Ltd. If you wish to cancel your whole order and return it to us, under the Distance Selling Regulations, you must let us know within eight working days of receiving your parcel. This can be done by calling us  on 01761411077 or via email at sales@bathpotters.co.uk. You must also notify us in writing stating the reason for the proposed return.No return must be made until you receive written authorisation.  You will then need to return the whole order to us, at your own expense if you have already received it. Once we receive the whole order back we will issue a full refund including the original delivery charge. Please note this does not apply to items which have been specially ordered for you  unless faulty or damaged.We ask that damaged items being returned are done so within 21 days of receipt and accompanied with a letter explaining the reason for the return and the position of the fault.Remember before you purchase if in any doubt of suitability of a product you can email us with any queries.If you feel the goods are at fault please contact us immediately and we will do our best to resolve the matter. The above conditions also apply.We want you to be entirely satisfied with every purchase made from Bath Potters.
Please note that it can take up to twenty one days to process a return.

What happens if I'm not at home when my order arrives?

In most circumstances a card will be left if you are not in. If you have not requested a safe place to leave your order, it will be taken back to the depot. Two delivery attempts will be made, then your parcel will be returned to sender. A re-delivery charge will then be incurred

Pallets are sent by our haulage company and we will ring you prior to delivery.

When can I collect my 'Click And Collect' Order?

We ask, where possible, to give us 24 hours notice after placing you order before travelling to us. This gives us a chance to get your order together, and check all items are in stock.

Clay FAQ
What is the best way to store my clay?

Hotter temperatures will encourage the clay to dry out faster even with the thick plastic bag, and freezing temperatures create a really strange texture in the clay requiring you to wedge or knead it really well before using it. The plastic bags do work really well especially if they are well sealed

What is the difference between Earthenware & Stoneware?

Earthenware is fired at lower temperatures usually not more than 1180°C. At this temperature the clay remains porous and the glaze will be a separate layer adhering to the surface.

Stoneware is fired to higher temperatures, maturing the clay and glaze at the same time. The glaze interacts with the clay forming an integral glaze/clay layer. Stoneware biscuit firings are usually around 1000°c and glaze firings 1230°C to 1300°C. 

Can I throw with airdry Clay?

The Creative Clay can be used in exactly the same way as any other clay, but of course you will be able to detect the nylon fibres during throwing.

Glazes & Glazing FAQ
What is the best way to fire Botz Gold and Reds?

Fire low 1040degC. Leave brick off slightly. Apply thickly.

Is my glaze food safe?

The only way to be sure is to have your glazed pot sent to Ceram Research to have it tested.

Can I use Earthenware brush-on glazes on Stoneware clays?

If stoneware clay is fired to maturing temperature it will be difficult to apply brush-on glazes as the surface will not be porous, if this can be achieved then the earthenware glaze might fire successfully but there is a risk of crazing. The glaze must be fired to its specified temperature. Some stoneware clays are dual purpose and can be used at earthenware temperatures. 

What is the difference between a stain and an underglaze & on-glaze colours?

Stains are used to colour clay and glaze and are very strong colours. Underglaze colour is finer ground glaze stain and normally contains a frit or flux addition.

Underglaze colours may also be used to colour glazes and clays but are primarily designed for applying to ware, either greenware or bisque which is subsequently glazed usually with a transparent glaze.They can also be used on top of a white glaze before firing, (Majolica technique).

On-glaze colours are fusible colour where all the constituents are melted together and finely ground, they are applied on top of a fired glaze and are typically fired to 700°C/800°C. They are also called china paints or enamels. 

Reglazing fired pieces

To re-glaze a fired piece you need to do one of the following:
Spray the piece with spray starch, let dry, then reglaze.
Spray the piece with sticky hairspray (usually the cheapest you can find), dry, reglaze.
Heat the piece first, with a heat gun or in the oven or kiln, then apply glaze, (my favourite).
Brush white PVA glue on, let dry, reglaze.
Microwave the piece for 30 seconds. (Some potters say this makes a huge difference, and the piece doesn't need to actually get or stay hot)
Add some suspension agent to the glaze (CMC gum or Bentonite.)
Add some detergent / shampoo to the glaze (baby shampoo is good because it doesn't foam)
To improve your odds further, wash the pot first with ammonia or detergent, wearing rubber gloves, and don't touch it. The oils from your fingers can prevent glaze from sticking.
And... Don't use too much of anything. If you get the coating too thick, you may prevent adhesion instead of encouraging it.
Read more here

How do I mix a glaze?

Following the recipe, weigh out all the ingredients. Place all the glaze powder in a container at least twice its volume. Add approx. 100ml of water to every 100g of solids.

Leave for 30 minutes to allow the glaze powders to absorb the water. This will break down any lumps and make for easier mixing. The glaze is now in slop form. Mix it thoroughly with a lawn brush, breaking up any large lumps as you go.

Pass the glaze through an 80 mesh sieve into its permanent container, and use the lawn brush to push coarse material through the sieve. This ensures that all the ingredients are of a small particle size and will disperse. Stir the glaze to check its consistency. It should be like single cream, depending of course on your method of application.

Glaze Settling

Have you ever had a glaze that kept settling to the bottom of your bucket? This is a common problem and may result in firing problems.

When a glaze settles out, some of the heavier components of the glaze settle to the bottom of the container. If you try to use this glaze without thoroughly remixing you will be applying a glaze with key ingredients missing.

A glaze stays in suspension due to the presence of various types of clays, such as bentonite, and/or gums, such as CMC. One common cause of settling out is the addition of too much water to the glaze, which dilutes the effect of the suspending agents and allows some of the glaze ingredients to settle out.

Another possibility is the growth of bacteria which will consume an organic gum, such as CMC, and will lead to loss of suspension.

To prevent bacteria growth do no return used glaze, which has been poured out of the original container, back into the original container.

Also do not introduce possibly contaminated objects, such as brushes, into the original container.

Storing glaze in a hot or sunny environment may also encourage bacteria growth. Freezing can also destroy the action of CMC. And glaze ingredients such as frits, nepheline syenite, soda feldspar and other slightly soluble materials slowly release sodium ions which can deactivate the suspension agent, making it ineffective.

Read more here

Glaze Settling: remedy

If a glaze has settled out, but has not gone rock hard in the bottom of the container, you can add CMC or bentonite, if you happen to have it.

Calcium Chloride or Magnesium Sulphate are also suspending agents. They would require clay to be present in the glaze mixture, so try adding about 3% bentonite to your glaze. A little trial and error is required to determin the exact amount.               

However, you can also use Epsom salts to suspend your glaze. Epsom salts can be readily purchased in most chemists.

First you need to create a saturated solution of Epsom salts by dissolving them in a cup of warm water until no more will dissolve. Then add this solution slowly and carefully to the glaze while continuously stirring the glaze. It should require less than approximately one teaspoon of Epsom salt solution per gallon of glaze.The quantity will depend on the severity of the problem.

If a glaze has got too hard at the bottom to mix back up drain all the liquid off, work on dissolving the solid into the Epsom salt / water mixture, then add the rest of the glaze liquid back in.

Read more here

Can I mix Glazes?

Yes it is possible to mix say yellow and blue to make green, Its best to test first though!

Do you have a remedy for Pinholing?

When small dots of unglazed or depressed areas appear in the glaze surface, this is called "pinholing". Pinholing occurs when gases in the glaze and clay bubble up to the surface. The gas bubbles pop and a 'hole' appears, which doesn't fuse over.
Remedies:

  •  Fire the glaze higher

  • Soak the kiln 15minuets at peak temperature to keep the glaze in a liquid stae a little longer. 

  •  Wipe all dust off bisque ware

  •  Spray bisque ware lightly with water prior to glazing 

  •  For earthenware, a good tip is to ensure that the piece is bisque fired 2 cones hotter than it is glaze fired (i.e. when glaze firing to cone 05, bisque fire to cone 03).

  •  a slower bisque firing cycle to give the carbon more time to burn out;

  • lowering the glaze firing temperature by 1 cone (for earthenware only); or using a glaze with more flux.

What are the basic ingredients of a glaze?

Every glaze is made of the following 3 materials:
1. Silica – Creates glass. Examples: quartz, flint, pure silica
2. Alumina – Stiffens the glaze so it doesn't slide off the clay. Examples: clay (kaolin, ball clay, or fire clay), alumina hydrate
3. Flux – Causes the glaze to melt at a low enough temperature to be used in ceramics. Examples: feldspar, whiting

What's the differnece between Engobes and Decorating Slips?

Slips are predominantly liquefied clay; they usually are applied on wet to dry greenware. Engobes usually have a lower clay content and also can be used on bisque-fired ware. The word slip generally is used to describe any clay in liquid form. All slips and engobes can be colored with oxides, carbonates and stains. Sometimes very crusty surfaces can be made by applying slips and engobes over the fired glaze surface and then refiring.

Kiln Firing FAQ
At what temperature should I fire the kiln to for the first firing and following element replacement?

New elements fired to around 1100°C in an empty kiln will develop the oxide layer on the surface of the wire more quickly and should improve element life. If the glaze or clay being used produces aggressive fumes such as fluorine then this is worth doing, with usual materials the benefit is marginal.

At what temperature can I open my Kiln after the firing cycle?

If the door is opened when the kiln is above 200°C there is a risk of cracking the pottery because of uneven cooling at the critical point of sudden contraction. 

An element has come out of its groove - what should I do?

Moving or bending an element can result in it snapping as they become very brittle with firing. First heat the element to red heat with a blow lamp and then bend to shape with long nosed pliers. Staples made of element wire might be helpful to hold it more securely.

The bricks on my kiln are cracking?

New designs, materials and methods of construction are minimising this problem however some cracking may occur because of expansion/contraction stresses. Opening the kiln too early will increase the risk of bricks cracking. As long as they are not structural even severe cracking will not affect the firing performance.

How fast should I fire my kiln?

The first firing, (bisque or biscuit) should be quite slow to avoid moisture trapped in the clay from turning to steam which will shatter the ware The best approach is to fire   50degC-100degC  per hour up to 600degC then 150deg per hour up to 1000degC For glazing  150degC per hour  500 degC then 250degC  up to maturing temperature of glaze

Botz Glaze FAQ
How often should I apply BOTZ glazes ?

In general, 2 – 3 layers, except for the two transparent glazes (BOTZ 9102 and BOTZ 9106) and the two crackle glazes (BOTZ 9351 and BOTZ 9352). Apply only a thin layer of the latter, i.e., without dilution or 1 – 2 times slightly diluted. For red colours and gold glaze, rather apply 3 times, see question 5.

How long is the shelf life of BOTZ glazes ?

After the purchase from the dealer, the glazes will have an average shelf life of 2 – 3 years, some even distinctly longer. Good storage conditions, i.e., no extreme temperature variations, no frost, no heat will extend the shelf life. Solidified glazes can be stirred with water to become spreadable again.
Tip: thoroughly clean the container edge after use, add some water to the container, stir in with next use.

What is the biscuit firing temperature ?

The first firing (biscuit firing) traditionally was fired at 900° to approx. 960°C. For powder glazes, a porous biscuit ware was important so that the mixed powder glaze could adhere roughly to the biscuit ware. However, BOTZ Flüssigglasur can be applied very well to ware biscuit fired at distinctly higher temperatures as it contains a glue which helps the glaze to adhere firmly. Advantage of a biscuit firing temperature of approx. 1020 – 1050°C: with a high biscuit firing temperature, the clay´s gassing process has been concluded to the greatest extent and the glaze will not be “disturbed” by clay gases in the 2nd firing, i.e., there will be less bubbles and craters. Some BOTZ users fire stoneware clay in the first firing at approx. 1220 – 1250 °C, thus the clay is sealed and frostproof and then, they use BOTZ Flüssigglasuren for the earthenware range at 1050°C.

Can I mix BOTZ glazes with each other ?

Very beautiful results can be achieved when you apply one glaze on top of the other. Mixing the glazes into each other in the earthenware range will not yield exciting results with all of them. Well suited are opaque glazes without effect and in particular also BOTZ Steinzeug (see also Notes under Tips Steinzeug).

Red will not turn red, Gold will not turn gold, what happened ?

Red and gold colours in ceramics often are very sensitive. Very stable are red BOTZ colours (BOTZ 9601 – BOTZ 9605) and BOTZ Gold (BOTZ 9541) when you observe the following 3 rules:

1. Apply a thick layer
2. Fire at low temperature (i.e., up to 1040°C)
3.Admit oxygen to the kiln, or do not set the ware too close inside the kiln so that air can circulate easily.

For Lava (BOTZ 9606) and Korale (BOTZ 9607), you can fire at a higher temperature, however, carefully observe the oxygen supply. White edges are part of the appearance with these glazes.

Can I overglaze already fired glazes again ?

Most of the time, this works pretty good, if you, for example, applied a thin layer and wish to apply the same glaze again. The drying time on fired glaze, of course, is longer than on unglazed biscuit ware. If you wish to apply a different colour over a fired glaze, the result is not quite foreseeable, but often exciting. For good adhesion, you can heat the fired ceramics again to 60 – 100 °C prior to renewed glazing.

Some BOTZ glazes smell during firing, will toxic gases escape ?

It is important to know that each firing, i.e., also a biscuit firing, produces harmful gases in the ceramics.You should exhaust these fumes with an exhaust air system (e.g., see www.kerablu.de) or provide for good ventilation and aeration in the firing chamber and, if possible not work inside the firing chamber during firing. The sometimes intense smell of BOTZ glazes (approx. between 200 – 300°C) is no more dangerous than inodourlessly firing glazes. Interpret it as a hint for insufficient ventilation. The bad smell annoyance during firing will decrease if you let the glazes dry thoroughly before firing.

Are BOTZ glazes "food-safe"?

The term "food-safe" does not exist in the ceramics industry. It is important to use only lead-free and, if possible, only completely non-toxic glazes for dishes and drinking vessels. Some glazes are not acid-stable, i.e., if contacted by light acids, substances of contents may be dissolved from the fired glaze. Although all BOTZ liquid glazes are non-toxic, we recommend for safety's sake for dishes and drinking vessels only those glazes which are particularly resistant and marked by the "recommended for tableware" pictograph. For reasons of hygiene, this does not include, e.g., effect glazes or mat glazes as food residues may be taken up here.

Is there an optimum firing curve for BOTZ glazes ?

You can fire BOTZ Flüssigglasuren (earthenware) very well with the firing curves already pre-programmed in the control system, they do not require any specific firing curve to be entered. If you do your own settings, heat up to a temperature of approx. 600°C with approx. 100°C per hour, then apply full load until the maximum temperature of 1020 – 1060 °C has been reached, with a soak of 10 – 20 min. All samples in the catalogue were fired at 1050 °C with a 15 minute soak (except for Red and Gold, see question 5). Please note that a kiln frequently fires at higher temperatures in the upper range than in the lower range.

Stoneware glazes are to be fired with the same heating speed up to 1220 – 1280°C with 10 – 30 minutes soak, ideal is a final temperature of 1250°C.

Can I order from you directly ?

BOTZ Flüssigglasuren are distributed exclusively through specialized dealers for ceramics needs, craftwork shops and mailorder businesses. We would be pleased to give you the name of a dealer near you.

Are BOTZ glazes frost-proof ?

Frost-proofness is primarily determined by the clay rather than by the glaze. If the clay has been "sintered", i.e., it is sealed and cannot absorb water, it is perennial. Please ask your clay supplier for the sintering temperature of your clay. Liquid glazes can be applied also on highly biscuit fired ware, see also Question 3.

Are there any safety data sheets for BOTZ glazes ?

Most of the dealers have a CD-ROM with all BOTZ safety data sheets and can give you a printout of the requested data. Or contact us directly, we will be glad to be of assistance and send you the requested safety data sheets.

My glaze has run off strongly during firing, what is the reason ?

Our program includes some glazes which are intended to run off (see pictographs in the catalogue); in this case, just apply a thin layer to the lower area of your object. If, however, other glazes run off, the layer could be too thick or the temperature too high. Perhaps, you should verify the actually achieved kiln temperature by means of melting cones.