Making Soap
Who is Soap Impressions?



We are John Adams and Diana Thompson, long-time soapmakers and owners of Harmony SoapWorks. Early in 2004, we were fortunate enough to be able to purchase Soap Impressions from it’s founder, Ann Perius-Parker, who had created the company as a way of providing soap makers with a unique way to embellish their soaps.

Following in Ann’s steps, we work with soapmakers to help develop the best design to create a unique and personal stamp that will identify and “brand” their soap. Each stamp is then made and tested to make sure that it will work effectively. We look forward to working with you to create your own personal stamp.

What are these stamps made of?

Your custom stamp will be made of a brass plate attached to a hardwood base.

Ready-made stamps with decorative designs are made entirely of a zinc alloy.

Won’t the metal parts of the stamp get ‘eaten up’ by the lye?

Since saponification should be complete by the time the stamp is being used, there is little chance of the lye damaging the brass. Do keep in mind that these stamps are not guaranteed to withstand contact with lye-heavy soap or a strong lye solution. It is always a good idea to check the pH of your soap before stamping it, both for the preservation of your stamp and your skin. And of course, be sure to wash your stamp after each stamping session to remove any lingering particles of soap.

What is high quality electronic artwork?

It’s a high resolution graphic (300 dpi or higher), black on white and at least as large as the stamp that you want made. That is, if you want a stamp that is 1″ wide, the image should be at least 1″ wide (at 300 dpi).  We can accept files in many different file formats as long as they are high resolution and black on white.   If you do not have an electronic version of your image, you can mail a very sharp, clean black on white print copy and we might be able to get a good enough image by scanning it.

When is the best time to stamp my soap?

The same variables that affect the hardness of soap also affect the timing for stamping soap. The percentage of hard oils in your formulation, the amount of liquid you use, the heat and humidity of your location will all influence the timing. Usually stamping within the first week after unmolding works best.

To find the best time to stamp your soap, do the following test: Start by making your usual formula, unmold, cut, and let your soap dry as you normally would. Every day, take one bar from the batch and stamp it. The first few days the soap might still be too soft or sticky and the impression not as clear as you’d like, but keep stamping a sample bar every 24 hours until you get the image that works best for you. But don’t stop there, keep going a few days more to find out how many days you have to get a clear crisp image before the soap gets too hard. Do this with a batch or two and you’ll soon know what works best with your recipe and conditions.

Can I use these stamps on glycerin (melt & pour) soap base?

Melt & Pour soap can get very hard and may be more difficult to stamp than cold (or hot) process soaps. To make sure that you can still easily stamp your M&P soaps, take them out of the molds as soon as possible and stamp them while the soap is still somewhat soft. You may have to use just a few more taps with a mallet to get a good image stamped on the soap.

If you are not going to be able to stamp your soaps soon after unmolding them, try adding just a bit of distilled water (1-2 oz. per pound of soap) to the soap base before you pour it into the molds. This will keep the soap soft a bit longer and will give you more time to stamp. After stamping, just age the bars for a few days and the excess water will evaporate.

Stamp design and sizing tips

Please read our documents on Design Notes and Stamp Sizing.

Design Considerations

Your handcrafted soap becomes more unique and distinctive when stamped with your name or logo. The design for your stamp should be unique and recognizable so your customers will be reminded of you and your great products every time they see the design.

When creating this design, simple is always best. Complex designs, shapes, or detailed fonts do not make the transition to a stamp well. The best designs are simple and clean, with open space between medium thick lines. Usually a name or a logo (but not both) is the most effective.

These butterflies help illustrate what works and what does not. The design on the left works very well for stamping soap, but the other two have far too much detail to make a successful stamp.

Too much detail WAY too much detail!

Remember, you want a clean, sharp image that will be recognizable through several uses of the soap. This will remind your customers just where to find more of that wonderful soap!

How to Make a Great Impression

1. To get the best impression, be sure to cut your bars evenly with as flat a surface as possible. An uneven surface will give you an uneven impression.

2. Let your soap ‘breathe’ for a day or two after cutting before stamping it. You want your soap to be soft enough that it takes the impression well, but dry enough that the stamp releases easily. Depending on your recipe and climate, stamping your soap sometime within the first week after cutting usually gives the best results. By varying your recipe (hard oils vs soft, amount of liquid in your formulation, etc.) a considerable amount of control is possible. And with a bit of practice you’ll soon find the optimum time for stamping with your given recipe and climate. (Tips for determining the best time to stamp)

3. Position the stamp on your soap, and give it a couple of easy taps using a hammer or mallet. Practice a couple of times first on a scrap piece of soap and you’ll soon get a feel for how much pressure is needed.

4. You can use the stamp with commercial pre-made soap bases (melt & pour). Just remove the soap from the mold as soon as possible and stamp immediately. You can also add a bit of distilled water (1-2 oz. per pound of base) to the soap to keep it soft and “stampable” longer. (M&P tips)

Download our document on Print Stamping Instructions by clicking HERE.

Care & Maintenance

After use rinse your stamp under running water and using a soft brush, (a toothbrush works well) scrub off any soap particles that might remain. Rinse again and dry the stamp thoroughly before storing it.