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screen printing => Equipment => Topic started by: Squeeky on September 17, 2016, 02:18:57 PM

Title: Flood Chopper Creeps Up
Post by: Squeeky on September 17, 2016, 02:18:57 PM
Hey Guys,
 On my UB head on a 2010 Diamondback, I keep noticing what I call "chopper creep' on the left side of the flood bar.  It moves upward gradually, especially on 50 plus runs. Has anyone experienced this? This head (2) was used as the flash head by the prior owner.

Replace chopper? Air leak?

Jack
Title: Re: Flood Chopper Creeps Up
Post by: spotcolorsupply on September 17, 2016, 02:33:56 PM
If you mean the adjustment handle tightens down as the press runs, causing the flood bar to rise..?

There are two hex set screws on the depth adjustment handle (I'm not sure what the proper terminology is) that apply tension to the knob/handle.

There should be a bit of resistance when you turn the depth adjustment knob/handle with the air off.

If they spin freely with no air applied to the flood, that is your problem.
Title: Re: Flood Chopper Creeps Up
Post by: jsheridan on September 17, 2016, 04:43:16 PM
Yes they have adjustment set screws in the top handle I want to say its a 3/16 Allen key. They only need to be just tight enough do not overtighten them
Title: Re: Flood Chopper Creeps Up
Post by: Squeeky on September 17, 2016, 07:37:48 PM
Thanks Brannon and jsheridan!

Actually, the adjustment knob is crazy stiff to turn by hand.

I will mark the knob to test to see if revolving and test the set screws

Jack





Title: Re: Flood Chopper Creeps Up
Post by: Inkworks on September 17, 2016, 11:58:04 PM
The set screws should have little delrin/HDPE inserts to ride against the threads if I'm not mistaken.
Title: Re: Flood Chopper Creeps Up
Post by: spotcolorsupply on September 18, 2016, 09:43:28 AM
The set screws should have little delrin/HDPE inserts to ride against the threads if I'm not mistaken.
You are correct!!
Title: Re: Flood Chopper Creeps Up
Post by: jsheridan on September 18, 2016, 01:46:46 PM

Actually, the adjustment knob is crazy stiff to turn by hand.



if they are under load they will be hard to turn. As is the case with the floor choppers in down position. when they chop for a print stroke, they are loose so what may appear to be tight, is free spinning when the load transfers the flood bar to the up position.

If you feel any kind of crunch of grinding while spinning the knobs.. the HDPE tips may have come off, replace them.

Title: Re: Flood Chopper Creeps Up
Post by: Screen Dan on September 19, 2016, 03:03:42 PM
The set screws should have little delrin/HDPE inserts to ride against the threads if I'm not mistaken.

When I was out at M&R a few years ago Francisco gave me a bag of them.  Made a huge difference.  We had this exact problem because over the years people had taken the set screws out and never put the inserts back in.

After I got all of my press's chop knobs working perfectly I decided to help out the other presses.  I clipped small squareish chunks off of the clear Wilflex ink bucket lids at the thick part.  They did the trick nicely in place of the real inserts.  Certainly better than going without.