Mimaki JV5 Banner Material Warping Problem

[signdepotarizona]

I have been at this company for a bit over 3 months.
I am extremely computer savy & have alot of printing experience.

But the previous "occupants of my job" didn't exactly leave notes.
And all the settings on our Mimaki & Onyx Poster Shop are wacky.

When recently printing on banner material,
the banner material gets waves almost instantly.
Problem is, the whole print head assembly will bump into them
dragging the ink across the banner.

With no one here but me as my own expert, what settings am I not setting to fix this?
What settings do I need to read & post in order to tell what I am doing wrong?

Thanks

 

[gabagoo]

to much heat?
heads set to low?

 

[signdepotarizona]

Heat is at: Pre: 72 Prt: 70 Post: 70
We even tried with all heaters off, same thing.

Here's the odd Head thing.
The manual says "Available settings Values: [1.5mm to 7.0 mm]"
My Mimaki says: "Input Range: 59.05 mil - 275.59 mil"
My setting was the the minimum of 59.05

I increased it to 66.92
That helped but it still warped.
But it made it through the print without bumping the material.

 

[J Hill Designs]

lowering the pre-platen temp help me with banner buckling

 

[daveb]

If the materials warping it has to be either heat or reaction to the solvent, since it's not the heat I'd say you have a material problem. The material should not warp that much, certainly not enough for a head strike. What is the banner material, maybe some of the folks on here have had similar problems (there's a lot of junk out there)

Dave

 

[Letterbox Mike]

Not sure if the JV5 has the same measurement for heat as the JV3 and 33 but if that's in Celcius you'd be best to lower it. We run our banners at pre: 45, print: 42, post: 50.

It may also depend on the actual banenr material you're running. Cheaper bargain brands tend to not be able to take as much heat as better more expensive brands. We run Ultraflex at the temps I listed with no problems, but if I try a cheaper brand I might not be able to get above 38 for the pre or print heaters.

But if those numbers on the JV5 are not the same as the 3 or 33 ignore what I said.

 

[signdepotarizona]

What if none of the heaters were on?
The 3 temps are there but when I went to lower the Pre-platen (as just suggested)
All 3 said OFF.

I'm not a beginner here, but this printer is a learning process to me after all.

 

[Letterbox Mike]

If they're reading off that may cause it too. Without the heat softening the vinyl a bit to allow it to relax and lay flat, the tension of the material coming through the printer may be causing it to buckle a little bit. But that's speculation and I don't know if it would or could really cause extreme enough buckling to cause head strikes. Are the platens warm at ll or are they cool? If they're really not on, you need to get them working, otherwise you're going to have major drying and durability issues, especialyl on a JV5 which is notorious for being too fast for it's own good causing the ink to still be wet when it hits the takeup reel...

 

[J Hill Designs]

last minute thought - if its a fresh roll, you may need to roll some out so the printer doesn't try to tug so hard? like mentioned, just a thought

 

[Rooster]

If the banner material you're using is LG bannux (warps like crazy for me) try turning off the print heater and leave the pre and post on.

With the bannux I found by watching it go through the printer (you have no choice but to watch when you're sitting there trying to push down the warps with your finger) that everytime the print heater came on it would buckle the media. No matter what temp setting. Off is the only setting that worked.

The vinyl should still have enough heat from the pre-heater for the inks to bond. Especially on a JV5. My JV33 has no issues with it.

 

[RippinPC]

It could be many things. The JV5 feeds media so fast compared to JV3/33. It could be your roll isn't feeding straight. It could be that your material is sticking to the metal feed path (metal that gets hot when the heaters are on).

All Mimaki's can be set to C or F for heat. Either way, heat could be the problem.

I have seen JV5's that the feed roll isn't level to the platen causing media skewing and buckling. Try running a sheet through (not on a roll) to eliminate this. Don't use the take up reel either. Look for bunching up of the media just before the media goes under the pinch rollers. Make sure you look at both sides of the machine as the problem can occur at either end.

I know some customers who wax the metal feed path to reduce sticking.

The material itself may not work well. Ultraflex banner material is great, but you have to buy the mid grade stuff from them, the lower end stuff bunches up too much for 540x1080 6 pass bi direction (400+ sqft/hr) mode.