Cuprinol Ultra Tough Wood Filler

Cuprinol Ultra Tough Wood Filler is formulated to repair damage caused by wet rot and most major joinery repairs. It can be used indoors or outdoors on furniture, panelling, window frames and much more. It can be used to fill knot holes, screw and nail holes. It is fast setting, non-shrinking, weather resistant with good adhesion to sound wood. It can be sanded, filled, drilled, screwed and nailed when dry. Use Cuprinol Ultra Tough Wood Filler before varnishing, painting or staining bare wood.

• Gives long lasting weather resistant repair
• Can be screwed, sanded, filled and painted
• Resists shrinking, splitting and cracking
• Fills holes of any size or depth (under normal conditions)
• Solvent based

Always ensure the surface to be treated is clean, dry and free from any dust, algae, fungi or moss.

• To clean wood give it a good brush with a stiff brush to remove any dirt, debris or loose wood
• If your wood has been effected by algae, fungi or moss this must be removed and can be cleaned with products such as Cuprinol Decking Cleaner or Cuprinol Garden Furniture Cleaner
• Cut away decayed and very soft wood back to a sound base
• Allow wet wood to dry thoroughly before application
• For best results treat area with Cuprinol Wood Preserver

Before applying stir the product thoroughly and test a small area to ensure adhesion.

• Only mix an amount of Cuprinol Ultra Tough Wood Filler that can be used within 10 minutes
• Using a hard surface such as the plastic lid of the container or a wooden board, mix the filler and catalyst paste with a spatula or putty knife in the proportions of a golf ball size of filler to 40mm (1.5 inch) thread of catalyst paste from the tube
• Mix thoroughly until no streaks remain and the colour is uniform
• Adding too much catalyst will cause the filler to become very hot, to dry very quickly, and affect its performance
• Apply a thin coat of mixed filler to the repair, pressing well in to get good adhesion
• Immediately fill in the remainder of the hole, leaving slightly proud for smoothing down
• Allow to set hard, this takes about 30 minutes under normal conditions
• Smooth to the required contours using sandpaper or file
• Apply only in dry conditions, above 5°C and when bad weather is not forecast

Note: Always follow the manufacturer instructions found on the tin.

The repair can then be finished with either a paint or woodstain. The filler will accept paints and woodstains such as Cuprinol Garden Shades or Cuprinol Garden Furniture Stain. Although the degree to which it may show through will be influenced by the preparation, the nature and characteristics of the wood as well as the type and application of the wood stain. Try a test area to ensure satisfaction before proceeding.

Q. Can Cuprinol Wood Hardener be applied to wet wood?

A. No, wood hardener cannot be applied to wet wood. The wood needs to be dry thoroughly before applying the wood hardener.

Q. Can I apply any paint over Cuprinol Ultra Tough Wood Filler?

A. This product is compatible for both solvent and water based paints as long as the hardener is completely dry.

Q. What is the difference between a wood filler and a hardener?

A. Wood hardener soaks into wood that is rotting and hardens the wood. Wood filler is used to fill cracks or holes. Both can be painted or stained.

Q. How long does it take for the Cuprinol Ultra Tough Wood Filler to dry?

A. This takes about 30 minutes under normal conditions. Apply only in dry conditions, above 5°C and when bad weather is not forecast ensure wood is also dry.

Delivery - All orders placed on a working day before 3pm will be dispatched on the same day for next working day delivery. Orders placed before 3pm on Friday will be delivered on Monday (excluding bank holidays). Orders placed on weekends and Bank Holidays will be dispatched on the next working day. 

Delivery of Tinted Products - Tinted paints are dispatched in line with our express order process, shown below. However, due to their bespoke nature, please allow up to an additional 5 working days to accommodate any potential courier delays or delivery issues before receiving a refund or replacement.

We strongly suggest customers avoid booking tradespeople until they receive their order. Next Day Paint will not be held liable for any costs incurred due to order processing errors, delivery delays, or other issues that may result in financial loss.

Delivery Options

Express Shipping - £3.99

Order by: 3pm, Monday - Sunday

Expected delivery: Next working day, 8am - 9pm

Orders placed on weekends or bank holidays will be dispatched on the next working day for delivery on the following day

AM Delivery - £12.99

Order by: 2pm, Monday - Sunday

Expected delivery: Next working day by 2pm

Orders placed on weekends or bank holidays will be dispatched on the next working day for delivery on the following AM

Late Cut-Off - £5.99

Order by: 4pm, Monday - Friday 

Expected delivery: Next working day, 8am - 9pm

Orders placed on weekends or bank holidays will be dispatched on the next working day for delivery on the following day

Saturday Delivery - £9.95

Order by: 2pm, Friday 

Expected delivery: Saturday, 8am - 9pm

Standard Delivery (Out of Zone Postcodes Only) - £6.99

Order by: 3pm, Monday - Sunday 

Expected delivery:  3-5  working days, 8am - 9pm

Orders placed on weekends or bank holidays will be dispatched on the next working day for delivery on the following day

We do not deliver to the Channel Islands or the Republic of Ireland

Certain postcodes delivery times and charges may vary please head to the cart to see your available delivery options.

Returns

We offer a 14 day money back guarantee for all goods shipped correctly that are not required. If the item is not required, please send the item back for a full refund in its original condition, unused with its original packaging. Please note return for unwanted item is at your own expense.

Contact us as soon as possible to inform us you will be returning the product either by a contact form or by calling our team on 0161 960 0217.

All tinted paint purchases are final and non-refundable. If you're unsure about your selection, please refer to the product listing or contact us for guidance before ordering. Once mixed, tinted paints cannot be returned or refunded, regardless of delivery delays or changes in circumstances.

While we aim to meet delivery timelines, we are not responsible for delays caused by couriers, weather, or other external factors.

We recommend ordering samples or colour charts before purchasing. While we strive to represent colours accurately, screen settings and surface types can affect appearance. Opened tins cannot be returned due to dissatisfaction with colour.

For non-tinted products, we offer a 14-day money-back guarantee. Items must be returned unused, in original condition and packaging, at your own expense.

Damaged Paint

Please visit our damages page, where we can help resolve the issue for you. 

Incorrect Item

If we have sent you a different item from what you ordered, we will be happy to organise an exchange for the correct goods at no extra charge to yourself, please get in touch to organise this.

Faulty Items

Faulty items can be refunded or exchanged within 30 days. All returns are tested, and if no fault is found, no refund will be issued you'll have the option to have the item returned. For faults discovered after 30 days, please contact the manufacturer for further support.