I have a fairly new HM1. My first large order was for 85 front/back white print on red shirts. They printed just fine. I had to stop once and do a head cleaning due to a decline in print quality. I have done a few smaller jobs, and I just finished a front/back order for 112 shirts with colored graphics on a black cotton. My customer from the latter order is now angry with me, because thirteen shirts are noticeably different than the others (appear faded).
I figured out that print quality seems to decline with each printing. I had already learned that I had to stop and do a head cleaning after about 15 shirts, but apparently that was not often enough. Because the decline was gradual, I missed the increasing fading with each shirt.
Should print quality be consistent from shirt to shirt, or is the declining quality between head cleanings to be expected? And how often should I have to stop and clean the print head?
I find myself having to reprint 13 shirts to keep the customer happy, and that is killing my profits. Frequent head cleanings certainly don't help, as they take time and ink. For the record, I maintain my machine according to the manufacturer's recommendations.
You should not have to be doing head cleans that regular during printing. The machine should do its own m,ini head cleans on the run whilst printing and you should not have a print quality decreasing as you go on. It is hard to tell what is wrong without seeing the T shirts but may i ask if it is Banding or just fading in appereance? If is fading in apperance this could be the pre treating, If it was the head need ing cleaning all the time you would expect to see soem sort of banding somewhere. It maybe a starvation problem where the ink is having problems getting to the print head and once sucked back through with a head clean it is fine for a few prints then has problems again. Check to see all your bottles holes are clear and there is not crimps in any of the ink lines. Also check the dampers to ensure the ink can flow through these freely by drawing ink through them.
Thanks for the info. Banding is visible. I spoke with a tech today from the place where I bought the machine, and they had a couple of suggestions. One related to something you mentioned about ink being drawn to the print head. I ran three head cleanings back to back, popped the tops on the ink bottles, waited for five minutes, and then printed 22 shirts with no decrease in quality (except some banding was still visible). I'll check the dampers next. Again, thanks for the reply.
we had the same problem after muiltipe head cleanings the problem seemed to dissapear. However, we still have have to stop after 40 or shirts sometimes becuase of fading. We were told this may be from the humidity in our room effecting the print head and have ordered a humidifier to hopefully make some improvement.
Make sure you are keeping your white ink bottle at least 1/2 full. Also, does your HM-1 have the circulation system? If not you may want to look into upgrading to this system as it eliminates most ink flow issues on the white ink.
Shundal86 - interesting about the humidity. Any idea what humidity level is acceptable?
Don-SWF East - my machine does have the circulating equipment installed, and I do make sure all inks are at least 1/2 full. I am still getting noticeable banding. Any other thoughts on this issue, and do you have any comments about the acceptable humidity level?
Don-SWF East - my machine does have the circulating equipment installed, and I do make sure all inks are at least 1/2 full. I am still getting noticeable banding. Any other thoughts on this issue, and do you have any comments about the acceptable humidity level?
You should be keeping your humidity level in the 40-70% range for best results. How does your nozzle check look? Banding is usually a result of blocked nozzles. Also, make sure the wiper is cleaned daily on the HM-1 as the way it swings away tends to let the ink dry faster on it than on other styles of printer. Buildup on the wiper can be transferred to the face of the printhead causing minor surface clogging to occur. If the white does show a fir amount of nozzles not firing properly, you may want to clean the printhead face with isopropyl alcohol to remove/break down the surface blockage.
I recommend purchasing a humidity gauge (hygrometer). You can find digital models for as little as $10 at Home Depot, Lowes, or a local hardware store. Mount it right beside your printer and you will always know if your humidity level is correct. Banding can be caused by several factors. I don't believe you mentioned doing nozzle checks. You should do a nozzle check every morning when you start to use your printer to check that your inks are fully coming through your print head. If you're getting broken lines then it means you're not getting full ink flow through the print head which will definitely cause banding.
I agree, it sounds like it could be humidity as well. I keep mine at at least 50% and it seems to work well. If it gets below there I do start seeing some minor banding. Also doing a flush of your machine once a month, with distilled water and cleaning solution (50/50 mix) tends to keep any buildup out of your dampers. Doing a monthly flush of the system and keeping proper humidity, keeps my machine printing at its best. This is of course in addition to the regular maintenance stuff
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Declining print quality 
