Speedball 001050 Underglaze, White by Speedball

Here’s a short, personalized review you can use: ⸻ I’ve been using the Speedball White Underglaze on my pottery pieces, and it’s been a great addition to my studio. Once I gave it a good stir and thinned it slightly, it brushed on beautifully—smooth and opaque in just two to three coats. I love using it for sgraffito and surface designs where I want crisp, clean lines, and it fires to a nice bright white under clear glaze. It holds up well through bisque and glaze firings, even at Cone 6. Definitely a solid staple for any potter looking to add reliable white detailing to their work. The only concern that I feel obligated to state about this product is that if you’re going to apply a clear glaze over it, you definitely should be using Speedball clear because it does not seem to like when I use another brand’s clear over it and will occasionally bubble or crack if I don’t use the Speed ball clear.. I called Speedball to ask them about this problem and they confirmed that this is a known issue.

Excelente producto, vino bien empaquetado y cumple con mis expectativas

I like that the bottle is the same width top to bottom, this allows even a wide brush to be dipped into the bottle easily. I use 3 coats at cone 6. The result is opaque, pure white without tints of other colors. Additionally, this white can be used in 2 or 3 coats beneath other glazes to give clean, bright results. White, red and brown clays can make glazes appear dull or "muddy", if you use this white in a couple of coats at greenware (recommended) or bisque, it's as if the glaze you apply over this underglaze has been applied to a porcelain type clay. You can use it alone or beneath other underglazes, other opaque or translucent glazes including clear. I've used this white to cone 10. If used alone to cone 10, be sure you have 3 full coats, allowing each coat to dry before applying another and if you're firing higher than cone 6, maybe add a 4th coat to be safe that you have good coverage. I've had this brown slightly in high fire, atmospheric firings such as wood fire, soda fire and salt fire. Hope helpful!

Overall good product. I would advise a bit of vigorous bottle shaking prior to any use as the material can get a bit lumpy. Once shaken it applies well and two thin coats generally does the job. The bottle design has recently changed and I prefer the old design as I pour the underglaze out onto my work surface which was easy to do with the narrow neck of the original bottle design. I do have issue with the recent price jump. A 16 oz container of Speedball Underglaze was $14.49 the beginning of September but had jumped to $20.77 by the beginning of December. I have found a cheaper supplier and have saved over $75 on an order of 12 bottles.

***UPDATE*** I reached out to Speedball directly and they immediately sent me out a replacement that was perfect right out of the bottle (4th pic). Was it a pain to have to go through that to get a quality product? Yes, but the customer service was stellar and in the end I got what I paid for so it was worth it. I will purchase in the future with confidence knowing that they will make it right should I receive another bad batch. Original Review: I’m new to speedball underglazes so I don’t know if this is a reflection of their quality or the quality of the seller who sold this particular bottle but the underglaze I received was almost solidified when I opened it. I’ve been doing ceramics for 15 years so I just figured it needed some reconstituting but no matter how many times I power whisked it, the lumps would not dissipate. It went from the consistency of 2 day old oatmeal to the consistency of watery ricotta cheese. I ended up having to run it through a sieve twice and even that did not get rid of all the little globs. Application was terrible, all of the little lumps got worse with each coat. Sorely disappointed- shouldn’t have to work so hard to try to make something usable right out of the bottle only for it to still fail. Worth the extra money to go back to Coyote underglazes apparently.