Ink cart flush

What an ink cartridge flush does

An ink cartridge flush in your InkFlow system clears blockages, dried ink, and pigment build-up, especially in the white channel. Most operators run flushes to keep lines clear during changeovers or if a printer has sat idle during load-shedding or holidays. Running a flush cycle extends head and damper lifespan and keeps white underbases crisp, which is key for spirits, skincare, or promo bottles needing high opacity or vivid colour. If you print mainly transparent or frosted bottles and white pigment is critical, planned flushes are non-negotiable.

For continuous printing with standard colours, you might get by with fewer flushes. But when high humidity in Durban or Highveld powder makes settling worse, or you use thick underbases, the risk of nozzle clog increases. Here we give you a walk-through on flush cycles, with guidance tailored to South African conditions.

Who needs regular flush cycles and who does not

If you are printing daily with a full CMYK+W setup, including opaque whites for gin, rum or cosmetic lines, regular flushes are for you. Owners who batch print only every few weeks, or switch between customers and ink sets, should also plan on flush maintenance. If you only use spot colours or don’t lay down whites, a full flush may be less urgent, but skipping it for months risks dried ink and expensive downtime. If you outsource bottle washing and only use the printer for simple spot branding, talk to us first before running heavy flush cycles.

How the flush works in South African shops

A flush cycle runs cleaning fluid through the cartridge and print head using the InkFlow system’s programmed maintenance mode. You’ll need approved flush fluid, waste containers, and somewhere to safely dispose of fluids, check your municipal rules before you start. Good ventilation is important in small print rooms, especially during the Highveld summer. If your workshop in Germiston, Gqeberha or Bloemfontein gets lots of dust, expect more frequent flushes. Avoid using tap water or recycled solvents, as these can damage the cartridge or void your kit’s factory support.

Most flush routines take under 20 minutes. Print bays with three-phase supply and reliable backup power finish quicker, but even with load-shedding interruptions, the main risk is leaving fluid standing in the lines. Always restart and finish the flush on the same day.

Worked example: White underbase flush after a wet week

Suppose your Cape Town cosmetics line ran a long job with heavy white underbase on frosted glass and then stood idle for a week during a cold front. When you return, nozzle outputs are patchy and the white channel looks milky. The operator emails our contact form with the system serial and a summary of the issue. We reply with a step-by-step tailored flush procedure, covering correct fluid for your InkFlow model, lighting and ventilation tips, and what to check before restarting. After completing the flush, test prints show the white is back to full opacity, so you’re ready for the next run. This avoids having to order an emergency head or call a technician just before a big spirits label shipment.

For more technical troubleshooting or spare part help, see our spares and pads and fixture care pages.

Before you email us: What to prepare

Emailing for flush support gets quicker answers if you include all the right info upfront. This helps us send the correct procedure for your exact InkFlow variant and avoid back-and-forth. Have your machine’s serial number ready (usually found on the rear or in your logbook). Note which colour channel is affected, what ink and flush fluid you’re using, and how long since the last print or flush. Photos of nozzle check strips or head output help, especially if there’s visible streaking.

If you’re in a shared bay or print room, mention if you’re on single-phase or three-phase, as this changes the timing for some cycles.

• Machine serial number
• Type of ink in use (including white or metallic if relevant)
• Last successful print date
• Type of flush or cleaning fluid on hand
• Photos of the affected output or nozzle test
• Description of any previous error messages
• Power supply info (single-phase or three-phase)
• Your daytime contact details

Common mistakes and how to avoid them

Skipping regular flushes is the biggest cause of slowdowns and costly parts swaps, especially for shops near Durban and Gqeberha, where humidity thickens pigment in idle heads. Flushing with the wrong fluid or letting cleaning solution sit in the lines for hours will damage seals and invalidate support. Never try to clear blockages with syringes or non-approved solvents, the print head costs more than a few litres of flush. Running a flush during load-shedding without backup risks an incomplete clean and ink returning to the head, so always schedule around your power plan.

For more advice on printer upkeep, see our support page and the resources section for checklists and print room setup guides.