Long media clamp

[Colin]

On the bottom side of each long media clamp (SP540i) is a .6" x 2.6" clear raised strip of some unknown material. It is off to the outside edge. What is this for? The short media clamps don't have this.

 

[CanuckSigns]

must be new, mine don't have it. but i'm guessing it's to stop the clamps from grabbing the media. I had to put transfer tape on the bottom of my clamps because it would grab on glossy media and create a "stutter" as the media fed through.

 

[Colin]

Hmmm, thing is, the raised strips are on the outer edge where they don't contact the media (if you have the clamps at the outermost position).

 

[qmr55]

Could it be to guide the media? Hard to really tell without seeing it on the machine and/or in use.

 

[34Ford]

How much thicker is it? Looks like someone has glued it on for a thick media so the clamp want sit at a angle.

 

[CanuckSigns]

Hmmm, thing is, the raised strips are on the outer edge where they don't contact the media (if you have the clamps at the outermost position).

i'm guessing it's acting like a spacer to keep the clamp slightly elevated above the media?

 

[Colin]

i'm guessing it's acting like a spacer to keep the clamp slightly elevated above the media?

That's what I'm thinking. It appears to be a piece of that clear "Rock Shield" or "Tuff Guard" or whatever it's called. It's about 1/64" thick.

 

[Colin]

Looks like someone has glued it on for a thick media so the clamp want sit at a angle.

This is the way it came new from Roland 1.5 years ago.

 

[Wiggum PI]

haha, so no one ever used them, me either. Note to self, stick double sided tape on something and throw them in as 'specialty' lol

 

[Mike F]

i'm guessing it's acting like a spacer to keep the clamp slightly elevated above the media?

That's what I was thinking as well, probably so they're not pushing down on the media and affecting the feed speed.

 

[34Ford]

Just checked. Mine are the same.

 

[CS-SignSupply]

I believe it is a spacer to help keep the guide flat, as to not lift one edge of it up and reduce the potential of head strike.

Could also be there to disperse heat? If the metal guide takes on too much heat, maybe it will tend to stick to the media..?

 

[Colin]

I believe it is a spacer to help keep the guide flat, as to not lift one edge of it up and reduce the potential of head strike.

Could also be there to disperse heat? If the metal guide takes on too much heat, maybe it will tend to stick to the media..?

Both of those seem to stand to reason. Thx

My rep is at a trade show right now and is going to ask the Roland guy who's there. I'll report if I hear back.

 

[Wiggum PI]

None of the guides have enough downforce on them to affect feed rates, and the roland platen never gets hot enough to make them stick to anything, so I am curious as to their technical function.

 

[2B]

they are on our guides also

when our pair of VS 640 were installed the tech said that they are specifically design for use on banners to keep the edges from curling and having head strikes.

the "film" IMO is there to keep the metal from leaving marks on the edge of the material be it banner or vinyl.

 

[WYLDGFI]

Possibly a teflon of some sort to allow the media to not stick to the clamps....would allow for proper advance of the media. our XC540 has it.

 

[Colin]

Possibly a teflon of some sort to allow the media to not stick to the clamps....would allow for proper advance of the media. our XC540 has it.

If that were the case, then they would have covered the entire face of the clamp, not just the outside edge. Without knowing what their purpose is, I'm not sure whether to locate the clamp well onto the media (more than what I'd like to if I'm wanting to maximize the print area), or to locate the clamp so that only about one third of it is on the media (which seems really minimal).

I'm looking forward to what the people at Roland have to say.

 

[Mike F]

If that were the case, then they would have covered the entire face of the clamp, not just the outside edge. Without knowing what their purpose is, I'm not sure whether to locate the clamp well onto the media (more than what I'd like to if I'm wanting to maximize the print area), or to locate the clamp so that only about one third of it is on the media (which seems really minimal).

I'm looking forward to what the people at Roland have to say.

The 2 holes on the clamps should be centered directly over the edges of the media, or at least that's what the manual said. The edge of the material should be peeking out halfway under the holes, if the makes sense. I still think it's so the clamps aren't pressing directly down on the media so hard and affecting feed speed. If you put the clamp all the way on the media and then slide it over before lowering the pinch rollers you can feel it drop down a bit when that strip goes off the media. They could also be there as a sort of guide in case the media tries to walk, they could help keep the media from sliding out from under the clamps. Just my thoughts though, I could be totally off.

 

[Colin]

I still think it's so the clamps aren't pressing directly down on the media so hard and affecting feed speed. If you put the clamp all the way on the media and then slide it over before lowering the pinch rollers you can feel it drop down a bit when that strip goes off the media. They could also be there as a sort of guide in case the media tries to walk, they could help keep the media from sliding out from under the clamps. Just my thoughts though, I could be totally off.

I think the above is correct. I had some feed problems a couple weeks ago, and couldn't figure out why. I suspect it was due to the fact that I had these strips partially located on the media. I've printed more banners recently and was very sure to located them so that the strip was about 1/16" - 1/8" away from the edge of the media, resting on the bed. The banner then fed perfectly.

So even if you have lots of extra media L&R of your print area, don't be tempted to place the clamps well in, or fully on the media. Always place them as I described above.