Clear Casting Epoxy Resin by Smooth-On

From R 304.00


  • Product name: EpoxAcast 690.
  • Clear liquid epoxy for castings that require a strong, hard finish.
  • Each cast layer should be between 3-10mm thick.
  • For making jewellery, river tables, pouring into moulds etc.
0.65kg (590ml)
1.30kg (1.18 litres)
6.50kg (5.91 litres)
Add to Cart

General points for all resin work
Resins are not simple to work with and you should not attempt resin art if you are not prepared to experience a learning curve. Start small and get to know your products and the correct methods.
Preparation and mixing are crucial for any resin project to be successful. Read and follow all instructions carefully. Only mix the quantity that you will use immediately as resins cannot be stored after mixing. The heat generated in a container of un-poured resin or in resin that is applied too thick can reach dangerously high levels. 
You need to take health precautions when working with resins so read safety and health instructions carefully. Avoid breathing fumes of this product. Use in a well ventilated area at minimum but an approved respirator is recommended. Avoid all skin contact and wear safety glasses, long sleeves and rubber gloves to minimise skin contact. This product is an irritant to the eyes, skin and mucous membranes. 
EpoxAcast 690TM Clear Casting Epoxy Resin
  • Cast in layers between 3-10mm thick. There is no limit to the number of layers that can be added.
  • Used to make jewellery and beads, used to create ‘river tables’ and poured into moulds to create castings. Excellent for adding pigments and colourants and for securing stones and crystals in resin art. Also suitable for electronic assembly encapsulation applications where its clear nature allows component identification. Castings cure with negligible shrinkage and are very hard and strong.
  • UV Stabilised (slow to yellow compared to non-stabilised resins).
  • Not very prone to amine blush but if this does occur take the steps required to remove it.
  • Not approved for food contact and not suitable for heat contact above 46oC.
  • Manufactured by Smooth-On in the USA.
  • The ratio of Part A and Part B is 100A : 30B by weight.
These are not detailed instruction. You should download and read the User Instructions as a PDF from this webpage before purchasing. A copy will also be included with your order. 
The most important characteristics of this resin system
UV Stabilised but clear unpainted resin will eventually yellow outdoors.
  • UV Stabilised (slow to yellow compared to non-stabilised resins). It will still yellow if exposed to UV light or sunlight for long periods or if exposed to temperatures above 46oC. If strongly pigmented or painted then it is fine for outdoor use.
Not very prone to amine blush but if this does occur take required steps to remove it. 
  • This makes it less sensitive to application conditions but as amine blush can occur, do not use the resin in cold moist conditions.
The liquid resin has low viscosity (thin with high flow).
  • It is often poured into moulds or onto surfaces that have retaining sides e.g. river tables.
  • If glass, small stones or powder pigments etc. are added they can make the resin thick enough to pour onto flat surfaces and not run. We have noticed that after adding pigment powders, a 15 minute wait allows the resin to thicken somewhat reducing its tendency to flow. You can see pictures of resin art made this way on flat boards. 
  • The low viscosity allows entrained air to rise up and escape easily. Torching is often not required and air is usually not a problem with this resin which is a big advantage. 
It can be applied in layers up to 10mm thick.
  • Do not exceed this thickness in a single layer. Thicker layers may generate too much heat during curing which can damage the resin or the mould
  • This resin is not ideal for very thin layers, use in layers between 3-10mm thick.
Long Pot Life but still fairly fast curing.
  • The long pot life allows larger quantities to be mixed and used than with short pot life resins. Pot life can be expected to be around 5 hours (for 300g batch) but it decreases in warmer conditions and for larger quantities.
  • The relatively fast curing time has obvious benefits. Thin layers, however, cure much slower. 
  • Cure time is dependent on layer thickness. Thicker layers get hotter and thus cure faster. Expect a cure time of around 24 hours for thicker layers of about 9mm. For thinner layers below 6mm thickness the cure time will be longer, 48 hours or more.
Castings cure with negligible shrinkage and are very hard and strong.
  • They resist moisture, solvents and dilute acids.
  • They can be machined and can be painted after the application of a suitable primer (remove all release agent before priming).
  • Cure times mentioned refer to the time it takes to feel hard (practical cure time). As with other resins the full cure time to maximum strength takes four week or more.
More information and videos
For more information, helpful tips and how to videos visit:

Basic safety and health information is contained in our User Instruction document which is sufficient for the casual user. The Safety Data Sheet for this product can be found in the Technical Section of this website. 

Keep out of reach of children
All our products should be kept out of reach of children under 5 years and anybody who may tend to place items or liquids in their mouths should be supervised. Even packing can become a choking hazard. 
Pack Size
Pack Size
0.65kg (590ml)
1.30kg (1.18 litres)
6.50kg (5.91 litres)
Starter Pack
Starter Pack
How to calculate the amount required
You must use a scale and resin mass. You cannot measure this resin by volume.
For a roughly rectangular shape multiply as follows:
Resin required in kg = Surface length in m  x  Surface width in m  x  required resin film thickness in mm x 1.1
For a roughly circular shape multiply as follows:
Resin required in kg = 3.14  x  Circle radius in m  x  Circle radius in m  x  required resin film thickness in mm x 1.1
If your rectangular surface is 1.2m x 60cm and you require a film thickness of 9.5mm
Resin required in kg = 1.2m * 0.60m * 9.5mm * 1.1    = 7.52kg of resin
Now work out how much of Part A and how much of Part B you need to give you the total requirement of 7.52kg
Ratio for this resin is 100A to 30B
To get 7.52kg total resin:
kg Part A required = 7.52/130 * 100 = 5.78kg 
kg Part B required = 7.52/130 * 30 = 1.74kg   

Recently Viewed