GlassCast 50 Epoxy Resin for Pen Blanks - 500g

The perfect epoxy resin for pen blanks

GlassCast 50 is a firm favourite amongst wood-turners and pen-makers who need a thick section (up to 50mm) casting resin that machines really nicely, cures bubble-free, stabilises and bonds to wood and is compatible with a wide range of pigments, dyes and decorative effects.

Any turners who have worked much with cast resin will know that there’s nothing worse than tiny pits on the surface of your barrel caused by air bubbles trapped within the resin! GlassCast 50 was designed to be self-degassing and to produce bubble-free castings without the need for a pressure-pot or degassing chamber, leaving you with silky smooth turnings that you’ll just want to keep touching!

For those who do want to use either a degassing chamber or pressure-pot to drive resin into wood in order to stabilise it further, there are a number of techniques for using GlassCast 50 in this way.

Why choose GlassCast 50 for making pen blanks?

• Highly machinable – Turns, cuts, and polishes beautifully.
• Self-degassing – Almost zero air entrapment, without degassing.
• Suitable for thick sections – Cast up to 50mm depth in a single pour.*
• Solvent free – 100% solids, no VOCs, almost odourless.
• UV resistant – Best-in-class protection from yellowing.
• Widely compatible – Works great with most pigments, dyes, and effects.

*50mm into a conventional mould, 25mm maximum depth into highly insulating environments like a wooden cavity or enclosure.

Getting Started

Ambient Temperature, Pot-Life and Pour Depth

The GlassCast range of resins, in common with all epoxies, generate heat as part of the curing process. The amount of time the mixed resin can spend in the pot, as well as the maximum depth it can be poured at, will vary depending on the ambient temperature.

For best results, we recommend working in a consistent room temperature of 18-20°C. GlassCast can be used in temperatures from 15 to 25°C but higher temperatures will reduce the pot-life and the maximum pour-depth of the resin significantly, as shown in the table below.

What to cast into

There are a number of options to choose from what it comes to what to cast your pen blanks into.

• Simple batten frame – Timber battens can be wrapped in release film (or even brown parcel tape) and screwed down to a plastic base to make a simple watertight frame or any size.
• Simple plastic frame – Alternatively, strips of polypropylene plastic can be hot-melt glued onto a baseboard to make a simple frame.
• Silicone moulds* – Specialist pen-turning suppliers offer high quality silicone moulds suitable for casting single or multiple resin pen blacks. Better still, some of these moulds allow you to cast the resin ‘tube in’ which means less wasted resin and less work to turn the blank into a finished pen barrel.
• HDPE moulds* – Alternatively, some suppliers offer sturdy HDPE plastic moulds in various sizes. Many of these moulds also offer tube in casting.

* Repeatedly casting epoxies into silicone of HDPE moulds will cause the moulds to degrade. Using Vaseline or similar as a release agent has been found to be very effective at extending the life of both silicone and rigid plastic moulds.

How much resin will I need?

The amount of resin need to cast a pen blank will vary depending on the size of the blank, whether you’re casting tube in and whether you’re adding other materials, such as wood, into the mould.

A typical 180mm x 20mm x 20mm blank, cast without the tube in would need 72g of resin. Casting 'tube in' or around wood will reduce this significantly meaning that a little resin goes a long way.

Adding different colours and effects

The number of ways that GlassCast 50 can be tinted, pigmented or otherwise modified to achieve different appearances is almost limitless. Our own range includes pigments and additives to create translucent tints, vivid opaque colours, and even sparkling metallic effects.

• Translucent tints – Translucent ‘see-through’ colours, like a stained-glass effect, can be achieved by adding just a tiny drop of our CULR universal resin pigments.
• Opaque pigments – Make solid opaque colours by adding a few drops more of the CULR universal pigments.
• Metallic-effect powders – For shimmering, swirling metallic effects, just add a pinch or two of our metallic effect SHIMR powders.

Combining, blending and marbling

Of course, much of the fun is in blending, combing and marbling colours and effects together. This is done by mixing separate pots of different colours and then bring them together in different ways in the mould. For the most dramatic marbling effects, the resin can be allowed to partially ‘gel’ in the pots before being combined and disturbed in the mould.

Inspiration, and help if you need it

Take a look in the GlassCast customer gallery to see beautiful, original pens and blanks created by other talented customers, all using GlassCast clear epoxy resin.