Acid-cured coatings

Acid-cured (AC) is a two-pack interior wood system: primer, clear topcoat and Promatch colours, mixed 10:1 with NCH999. It is the line we advise for new jobs so follow-on sheens stay on the shelf in Tullamore.

For new jobs, specify this range

We strongly advise that any new job is started on the current acid-cured (AC) products. That way, if more material is needed, it is on the shelf in Tullamore.

Typical gravity thinning is 20–25% ND4100 on primer, 30–40% on clear topcoat and 40% on colours. Pump settings are lower. The table below is the starting point; the product page carries the exact spray spec for that SKU.

How much to thin AC coatings

Novalk acid-cured systems mix 10:1 with NCH999, then reduce with Lacquerite ND4100. ND4800 is the anti-bloom option. Never use recycled or untested thinners.

Product	Gravity gun	Pump gun
AC white primer	20–25% ND4100	10–15% ND4100
AC clear topcoat	30–40% ND4100	20–30% ND4100
AC Promatch colours	40% ND4100	30% ND4100

Pot life on AC clear is up to 72 hours with ND4100; AC colours 48–72 hours with ND4100. For anti-blooming on colours, half ND4100 and half ND4800. Add thinners only when the product is going on the gun. Print the 2026 mix ratio sheets from the trade sign-in.

Print the 2026 mix ratio sheets

3 products