heidelberg sm 74 ink blade

[rbailleu]

we are having an issue with ink dripping behind the ink blade on our 2 color sm 74. it is a manual lever type laser slit blade. we have tightened up the levers so they completely shut off ink. we have check the sealant on the slits a it is fine. but we still get ink build up and dripping. is there something I should be checking.

 

[Cornishpastythighs]

Is this a new problem? have you changed anything in the blade lately? did the problem start after some event (ink key calibration/service)? Has your ink viscosity changed?

 

[rbailleu]

this is a problem we have had from the original purchase. we bought second hand. the blades had so much it behind them when we got it that it acted like a second blade and just smoothed out all the ink settings. so we cleaned it all out reset. not very well appearantly, so we just did it again. but it still seems to have a dripping/ leaking issue
no ink change

 

[Ret Heidelberg Instructor]

Here is a suggestion to try. You say that the press was used.You have cleaned and re-set the sliders. Check to see if the original factory painted seals (red or green color)on the screws that are at the sides of the fountain have been broken, if that is still possible. The original blade would have been set up with a gauge at the factory against the fountain roller and then locked and marked with paint. I was with a technician on a call once that was trying to get a good balance on the keys. He goal was to try and get an even ink film setting setting with the keys opened around 20% and 70% across the ink fountain roller. He would adjust with an Allen wrench at the 20 % value .He then would open them to 70% and check the ink film and make the same adjustments at higher ink setting. It may not be perfect but may help.Try this and then see your results. One other thing to mention, and I am sure that you have tried this. Check your side cheeks and see if they are OEM. Sometimes after market product looks good but doesn't quite cut it. I really saw this problem more so with after market ink foils. Hope this has been of some help.

 

[rbailleu]

we have cleaned and checked the sliders and greased. the blade looked original, but the original sealant on the laser cuts was coming off. so before I bought a new blade I reseaedl the cuts with a good grade of gasket caulk. it is still flexible and still intact. the setting of the levers was off quite a bit we evened up every thing but not according to the 20 and 70 plan. we just evened up at zero. I will check on the cheeks. we have never had to use foils with the laser slit fountains but should I be using a foil

 

[Ret Heidelberg Instructor]

You cannot use foils on the press you have. Those were designed for presses with CPC Ink Fountains that set up from a console. The sliders were designed for manual operation on 2 color SM 74, SM 52 and GTO presses. Even later Model QM46 Quickmasters had them. 4col Printmaster GTO's used sliders on all units. I also found that when setting them in job situations it was better to go up and then come down with the lever. It had a tighter feel then if you tried to nudge the sliders up.

 

[rbailleu]

This is what I thought. but when you mentioned foils I had second thoughts. I know what you are saying on the go up and come back down that method gives a good tension against the lever mechanism. should the fountain roller rest against the tip of the blade or higher up on the flat of the blade.

 

[Ret Heidelberg Instructor]

To be honest I am not sure. Does the blade edge have a slight bevel? If you close the slider keys tight with no ink in the fountain take a thin feeler gauge and see if there are any restrictions. You do not want to damage the roller. Check both units and see if one blade looks to be in better condition than the other. Short of ordering a new one from parts department to see and compare and then return it. (unfortunately re-stocking charges may apply).

 

[rbailleu]

yes the blade does have a slight bevel on the edge which I assume is what is supposed to rest against the rollers just slightly

 

[Cornishpastythighs]

I wouldnt think a metal blade should ever touch the roller even slightly.There should always be a tiny gap maybe .002"

 

[rbailleu]

yes I believe you are right