Anti Setoff Powder

Hi Guys
I am running a Komori LS440 2003 model. having a problem with anti setoff powder. I was running with the settings that i got the machine with but when backing up my jobs, the powder from the 1st side seemed to be too much hence had to wash the blankets after runnimg about 1500 sheets. i then made adjustments and my jobs set off. Unfortunately the IR drying on the machine is not working so i have to use powder only. On the powder unit GRAFIX DIGITRONIC 3000, there are 3adjustments that can be done. 1st is for paper size, right next to it is another adjustment in % which am not quite sure of how it works. the 3rd one is right below the powder container which i think is for amount of powder going through. I would appreciate if anyone can help me by telling me which adjustment is for what and the best way to deal with this. During long runs I am loosing time by stoping and cleaning blankets just after less than 2000sheets.

 

the sheet size just leave set to the maximum sheet size you use, percent i used to set around 30 - 35 on quite heavey coverage jobs, the dial under the container should stay on 1 on the first side, i used to leave the percent set to about 35 and on the second side i just turn the dial up.

 

thank you rolandman will try that and see how it goes but how was the powder when you were printing second side. am printing BkMCY and my main problem is on black. powder quickly builds up on the black blanket(1st unit). this is bothering me and want to get it right.

 

you should get around 10K sgeets minimum out before you even have to think about claning the blanket, try it at 35 percent and start to bring it down slightly if you can, as far as i recall you can get away with 28 percent depending on coverage,

let us know how you get on

 

I appreciate man think will let u know sometime next week at the moment am printing a job from one of our no nonsense clients so dont want to experiment with their job.

 

What size powder are you using ? is it possible its a larger grain? I run a Komori 226L with a basic puffer unit and dont have much trouble with powder on the 2nd pass....
anyway I would use the smallest grain powder I guess...32? not sure what your using but it does make a difference , who wants to stop and do blankets??....good luck..
I also got a better ink so I could reduce the amount of spray I have to run.....

 

hie guys well i tried running the dial at one it didnt work. Am now running the dial at 2, the other adjustment at 35% and there is an improvement though i think can still go down on my % adjustment. AM not sure of the size of the powder but its from Van International made in UK ther is this number on the box(BLUE BOX) 4453975. Thanks for your help will keep you posted.

 

if its the unit Im thinking of it has an adjustment of how much powder goes through the vibrator , you can adjust that to let less powder down , do you see 2 rings where the powder vibrates through? you can close that up tighter I think...some of those units Ive seen run on zero at 10% , like I said Id have to see the spray unit but look at that and tell me what you see inside the box where the powder hopper is.....

http://i423.photobucket.com/albums/pp320/xxstevexxb/BEdigital.gif

this is a spray unit , maybe not yours but I put a box around that adjustment I mentioned.....see if you have that.....

 

You can also run your sheets thru the press, no printing, on impression to dust (make sure you turn your powder off). This will at least allow you to print more sheets before you need to clean your blankets.

 

if you run the yellow first it seems to have less of an issue with powder blinding. a sheet vacuume on the feed board will help stop this. i never had a pre vac on my presses so we either dusted the sheets ( blank run) or put a home made broom ( a few rags duct taped to a cutter stick) on the feed board to dust the sheets.

 

Hie guys am back again. Finally i managed to get hold of the users manual. It says the adjustment in %age next to paper length adjustment is for the powder quantity. 30% to 70%is the optimum control, but a value of 50% is recommended for normal operation. As for dial adjustment, its a metering gap adjustment device. 0,2mm is a reference value at grain size 10 to 20 thou. A metering gap of 0,5mm is recomended when using coarse grades of powder. Have tried these settings and its working out. Anyway thanks to all your help and suggestions.

 

hi,Richie
I too have had alot of problems with our digitronic spray device.i completely stripped it down and i found hard spray powder in various parts of the device.I found that i have now reduced my powder settings by miles, i was only getting 5k out of the 2nd side through the press on a back up.Now i'm getting 10000 sheets though on the 2nd side. I suggest giving your unit a blast out with an air line before you go and try allot of different powders.Is there any chance you could take a picture of a few pages of the users manual for me as im curious to see exactly what the hoses actually do that are connected around the device.Cheers