Stiffener Guide: Choosing the Right Hat Stiffener for Your Next Project
Stiffening is an important part of the hat-making process, but with so many types of stiffener available, getting it right can often feel like a black art. We spoke to some top Milliners and Tutors to get their insights and help break down the most common types of stiffener in use for millinery today. Plus, check out our Quick Reference Guide to find the perfect stiffener for your material.
Solvent-Based Stiffener
Traditional Solvent-Based Stiffener is a reliable go-to for most materials, and works particularly well for felts and straw hat bases. It’s a good choice for light-coloured material in particular, as it is non-yellowing. “I still use Solvent based stiffeners when I am blocking a white/light fur felt, etc.”, says Carole Maher, “It really soaks into the felt and works well without yellowing.”.
Karlie Owen from Jettah & Till Design also loves solvent stiffener for felts and buntals, and gives a double-dose for parisisals. “I find the solvent gives a beautiful sheen to buntals. It is superior and, in my opinion, the only one I would use for felt. Straw parisisals I find usually need 2 applications.”
It’s possible to dial in the strength and finish of Solvent-Based Stiffener with the addition of a Thinner Solution, which can also help reduce any surface residue on dark felts. “If you add thinners to the solvent based felt stiffener, you will find there is no longer this residue film left - 2/3rds stiffener to 1/3rd thinners”, says Elaine Mergard from Hat Academy. “It does mean you will need to do 3 light coatings, leaving for 2 hours to completely dry”.
Working with solvent stiffener is straightforward – it can be applied with a brush or spray bottle – but it’s important to work in a well-ventilated space with breathing protection. It’s also flammable, which means it can’t be shipped internationally, and should be stored with care.
PVA-based Products
PVA-based products are a great all-round choice, and there’s lots of variety to experiment with. Rebecca Share from Hat Atelier says an off-the-shelf PVA is the basis of her go-to straw stiffener. “My all-time favourite stiffener is one I mix up myself to use on Sinamay. I mix 50% PVA wood glue with 50% water and brush it on straight after blocking the sinamay. It is super firm and doesn’t leave a windowpane effect like the chemical stiffener.”
Recently, specially designed PVA-based hat stiffener has become available, such as our CM Extra Strength Millinery / Fabric Stiffener. This has more solids than regular PVA glue, which allows you to achieve a stiffer result with fewer coats. In fact, this is one of the strongest stiffeners available, making it perfect for paper, straws and leather - but the strength can be adjusted by diluting it with plain water.
Carole Maher likes it on straws, leather, felt and silk linings - “it’s flexible and not too stiff, but holds its shape and keeps the material looking the same with fewer coats”.
PVA-based stiffeners are non-flammable, non-toxic and easy to work with – an added plus for Rebecca Share. “The bonus is there is no smell and therefore can be used indoors. Mix up a small container of the PVA/water mix and make sure the lid is airtight. I use a 1” wide brush to apply the stiffener - make sure you rinse it out afterwards”.
Millinery Gelatin
Biodegradable and non-toxic, this water-based stiffener is environmentally safe and user friendly. Gelatin Stiffener is generally used on delicate fabrics, such as in silk flower making, but can also be used on straw, felt or other materials.
Experimentation is key with Gelatin Stiffener. It comes in a powdered form, and once mixed with water, can be sprayed, dipped or brushed, and made thicker or thinner for different results.
It can leave a bit of a sheen, so when using with felt hat bodies it’s best to apply the stiffener in thin coats to the inside only. For straw, try different consistencies to find what works best for your particular material. Steaming the hat body while the stiffener is still wet can help it penetrate into the material.
Lacquer Based Stiffener
Our Lacquer-based Stiffener is made from a natural resin, and comes in a powdered form that should be mixed with 99% Isopropyl Alcohol before use. Easy to use and quick-drying, it works well with most materials, but may stain light coloured fabrics due to its pale amber colour.
Stored in an airtight container, the mixed solution is shelf-stable, so it’s best to make up a full batch and then use it over time.
Lacquer Based Stiffener works well on felts, straw, lace and some silks - as well as synthetic materials, but as always, testing is key.
Other Stiffeners
The world of fabric stiffeners is vast, and there are some other choices that might be good to have in your back pocket. Powertex is a versatile art medium that can also be used as a powerful fabric stiffener. It works well on all absorbent natural materials and fabrics and is also great for more exotic and experimental materials, such as paper, cardboard, and fibreglass. It’s available in a transparent variety which won’t change the colour of your material, but it also comes in a variety of colours and takes pigment well if you do want to shake things up.
Shellack Flakes are another time-tested millinery stiffener, that works particularly well on dark felts. Soaked in methylated spirits or rubbing alcohol, they make a similar solution to our Lacquer-Based stiffener, but with a deeper amber hue. Carole Maher recommends experimentation – “You need to do a lot of test samples on felt and straw to find the best strength for your requirements. I tend to use a very thin mix and lots of coats. You can get a soft finish to a very, very hard finish depending on strength and number of coats. I use this for dark felts, most men’s hats, all Ascot top hats, and even Dressage 3/4 top hats, which were mega hard (until they switched to safety helmets). It’s also very good on natural coloured straw as it enhances the colour”.
Stiffener Tips
Whichever stiffener you choose, testing and experimentation is the key to success. Different materials interact differently with various products, and you can control the strength of all these solutions to achieve different results. We do have some extra tips though, to help you get started.
Karlie Owen recommends a dry iron when stiffening parisisals. “I find I'll stiffen a parisisal but then if it needs another iron, always use a dry iron - no steam or it leaves marks. Then, a second application by paint brush. Leave your brush and solvent in a glass sealable jar so you don't need to clean your brush! “
For blocking felts, which often have a bit of stiffener pre-applied, Elaine Mergard says steam is key. “The real secret to maximising stiffness in felts is thorough steaming before blocking - more than just a steam iron to block. You need to fill the hood with steam, and this helps release some of stiffener added during manufacture”.
And for all types of stiffener, Carole Maher has a pro-tip to stop container lids seizing.
“One final tip, all containers for stiffeners get lid locked and it drives milliners mad. Cut a freezer bag (from supermarkets) into squares and place one over the neck of the bottle/can, then screw the top/cap back on. The next time you will be able to open it very easily as the bags have some Teflon in them. If you can’t get freezer bags, then try cling film”.
Stiffener Guide
To help you choose the right stiffener for your next project, we’ve done some testing and put together a handy guide for different types of materials. Click here to take a look.
Special Thanks
Thanks to the Milliners and Tutors that contributed to this article and shared their advice. You can find their work at the links below:
Carole Maher — www.carolemaher.com.au | @thesydneymillineryco
Karlie Owen, Jettah & Till Design — www.jettahandtilldesign.com |@jettahandtilldesign
Elaine Mergard, Hat Academy — www.hatacademy.com | @hatacademy
Rebecca Share, Hat Atelier — www.hatatelier.com | @rebeccashare @hatatelier