Maintain UV ink line is the most annoying issue for UV ink line.
Check the following uv ink line issue step by step and you will definitely fix ink line issue:
- There is no ink in the ink container due to ink level sensor failed to tell the printer ink is empty. This issue also cause instability of negative pressure system. So you experienced good printing sometime but then banding issue happened because air go to negative pressure system to fail nozzle fire. Solution always keep ink level above 1/3 of the ink container. If ink level is too low and it’s easy to cause failure of filling ink. This solution eliminates empty ink issue with physic ink being always full.
- The ink pump was clogged and so there is no ink go to sub ink tank and so absolute there is no ink go to print head.
- The ink line was clogged. Agfa, Mimaki, Mutoh and Roland uv ink line is tiny and it’s easy to be clogged. Lavaink solution is that replacing uv ink line with industrial standard uv ink tubing inner diameter is 2 mm and outer diameter is 4 mm. This ensure uv ink line unclogged at all.
- The sub ink tank ink level sensor failed to tell uv printer to pump ink. So no uv ink go to sub ink tank and so there is no ink go to print head either. This is very normal issue for maintain UV ink line.
- The ink line is loosed or leaking. The most of possibility is from Sub ink tank to ink valve section. Solution: just replace old sub ink tank with brand new sub ink tank. Buy good quality all metal sub ink tank and never buy plastic sub ink tank. Some sub ink tank is metal but connector is plastic that is easy to be broken. Lavaink sub uv ink tank is all metal parts including metal connectors. Also all Lavaink sub in tank are tested to guarantee they are sealed perfectly.
- Negative pressure tubing is loosed or leaking. The most of possibility is connectors. Double check all connectors.
- Check negative pressure meter. It is normal if negative pressure meter cycles on and off about 20 seconds. The ink line was absolutely loosed or leaking somewhere if negative pressure meter cycles on and off every two or three seconds.
- Release water from air pump. Some old uv printer negative pressure is produced by converting positive air pressure and so there is too much water in the air pump. Solution is that just release the air pump valve to let all water out. We experienced one Agfa uv printer customer who never released air pump water when we check his printer issue. We released at least 3 liters water from air pump. This is the main reason to cause negative air pressure instability.
Keep perfect negative air pressure
Keep perfect negative air pressure is the key for maintain UV ink line. Different uv printer with different negative air pressure value. The principal is the higher negative pressure value with the higher sub ink tank level. For example, If your sub ink tank is two feet from your printhead and then your uv printer negative pressure value should be at least -3.0. Agfa uv printer negative pressure value is set up at -3.8 but EFI Rastek H652 negative pressure value is just set up at -2.0~-2.5.
Why buy good quality negative pressure system?
Monitor your negative pressure meter during the whole printing processing. Like Agfa uv printer negative air pressure is set up at -3.85 for colours. If this negative pressure value was changed from -3.85 to -3.5 and then that proved your uv ink line absolutely having big issues. This big different negative pressure value 0.35 [-3.85-(-3.5)] change is not allowed for uv ink line. Max negative pressure value change is just 0.2. You must check our above instructions from step 1 to step 8. Step by step check all of them to figure out what’s issue cause negative pressure in stability so much.
We experienced this situation due to ink was almost empty but ink level sensor failed to tell uv printer pump ink to sub ink tank. And that’s why ink pump pumps air to sub ink tank every time to cause big negative pressure value changed. Also absolutely cause printing banding issue. That’s why we required all our uv printer customers to keep ink level always 1/3 level above in the ink container. This ensure to eliminate the ink empty warning failed issue by making ink full in physic.
Why buy Lavaink negative air pressure system?
Most of uv printer negative pressure system is not good enough. Like old Agfa uv printer converts positive air pressure to negative air pressure. Also negative air pressure value is changed during printing. You have to monitor this negative pressure value during the printing processing. If this value is lower than -3.5 and of course your printer nozzle fire will be failed. So printing banding issue failed your whole printing job. Bad negative pressure system will waste you too much money.
Buy directly negative air pressure system
Lavaink negative air pressure system is directly produced by negative air pressure and also it’s automatically controlled negative pressure value unchanged during the whole printing processing. Like if negative air pressure was set up at -3.5 and negative air pump will works right away if negative air pressure is lower than -3.5 and then keep air pressure air value go back to -3.5 again. This ensure negative pressure value stable around -3.5 and max change is -0.1. This can guarantee Lavaink negative air pressure system delivery perfect negative pressure value at stability value.