Recently, I have problem with Agfa thermal plates. Does anyone have datasheet or technical specifications contains cutting tolerances? That would help a lot.

Are you looking for your size? The tolerance within box to box should be way less than a row of dots. These plates have to be same cut to register on many systems. Are you saying you have plates from Agfa that are cut crooked and or roughly, not same in a nice stack? That's a bad box and is not acceptable. Every plate in that box should line up or it's substandard, is mfg. defect.

Actually, these are not crooked nor roughly cut plates. They are just 0,5 mm bigger than nominal size and that causes position setting problems in Topsetter. I am just wondering whether or not 0,5 mm is accepted at CTP plates.

Hi plotter,

Not a fan of Agfa myself because of stuff like this. Yes, if your plates are not the size you ordered, and it's causing you a problem, then it's beyond tolerances. However, a .5 mm is not very much to be causing imaging problems.

This is why I don't deal with Agfa. They change slip sheets without notice, send poorly cut plates, always something with them. Kodak is a much better manufacturer and Fuji is even better. Agfa, had years of issues with them and their plates for CTP, never again. I would not cut them much slack, if you buy plates, you should expect good quality. A plate that is cut right, images right, prints right. Agfa is not the best supplier for consistancy. I used to use around 400 Agfa plates a day, it was always something. Good luck.
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Unfortunately, it is not that easy to change. The point why I came up with this tolerances thing is that I did not find any international standard about dimensions of CTP plates. However, I would like complain to the supplier I need to know what is the quality I can expect from these plates.

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Plotter:

I'm not sure why you are looking for any "standard" or "tolerances"on plate sizes? You tell your supplier what size you need to fit your presses and that becomes the standard for you. If they are cut wrong and are causing problems, in anyway, then they are "intolerant". You need to inform your supplier of this, tape up the bad boxes and send them back for a credit or new boxes of the right size. Do not start changing the settings on your setter. The next box of plates may be a different size altogether and you don't want to play that game. You said it is not an easy switch but is going through these problem any easier? I'm sure if you told them you were switching to a new supplier because of these ongoing problems they will easily and happily make sure this doesn't happen again. Just some advice, hope it helps.

filmroom1.

The Topsetter can fail a plate for either width (across drum) or length (around the drum. A plate first gets centered, then punched. If it fails for the width size, during centering, then it won't punch. If it fails when loading onto the drum, and gets kicked right out again, then it is the length that is wrong. The error message will usually tell you which was wrong, and in which direction. If your plate gets kicked out with no punch, then the width failed. If it gets kicked out with a punched edge, then the length failed.
The width is critical for centering the image on the plate correctly, and the length is critical for placing the tail clamps and keeping the plate on the drum (a little higher priority in my book!)
First, get a good METRIC ruler or tape measure, and actually measure your plate. start in on the tape measure about 10 cm and subtract the 10 off the other ends reading, since the ends of rulers and tapes are usually pretty nasty. Write these measurements down, and then check the "Plate" menu in the user menus (Media, Plate, etc menus) "Plate" will be where the Media is picked, and the size is set up, describing that plate. It is in mm. You might see a discrepency there, if you measured 1030mm, and the Plate menu's description is 1032...no good.
There should be a mm or two leeway, to accomodate for manufacturing problems. Does this happen on other plate sizes?
Also, There is a "teach" mode for setting physical parameters of the machine. You measure a plate, as above, and in a special menu, you input that size, then load a plate.You are effectively TELLING the machine that this IS a 700x1029 plate, and "please change any parameters necessary to recognize it as such, thank you!".
haha
This calibrates the machines measuring mechanism in both directions.
It's not uncommon to see some imperfections in plate sizes, and a Platerite/Topsetter should be able to handle a small 1.5 mm shift.
straight edges and squareness of the plate are not always perfect either. Trendsetters have fantastic registration, BUT, it is relative to the lead edge that rested on the pins, and the right edge, where the focus laser detected an edge. We would have people punching plates relative to the tail edge, which might not have been parallel ! Often, a good demonstration was to take 2 plates, and put them on a light table, with the 2 "straight" edges together. look at that! I see curves and gaps where the light shines through! Get me my Geometry book! haha.
Anyway, if it isn't a big deal, and a new box of plates came in and had size problems, I would just get in the habit of measuring the actual size, and inputing it in the "Plate" menu. At the very least, it's a good thing to know how to do on your machine.

We had the same problem with other suppliers; in my country is difficult to get a credit on "good boxes" on time; once we had to cut by ourselves the plates waiting for the "good boxes" to arrive (2 months latter); Heidelberg´s guys told us "unofficially" that plates could have up to 1 mm tolerance, so we are expertice to "adapt" our topsetter to any measure we get form the supplier.

Agfa tolerances are .5mm along with every other manufacturer. Most of the time .3mm is accomplished.

Ask your Kodak vendor Fuji Vendor or Southern Litho Vendor. Noone likes to talk about it but they all have it.

It is all about consistencey and every manufacturer has the same tolerances. Sorry to rain on any preconceived perceptions.

Also every manufacturer has problems with plates, as I stated before, I worked for Kodak and for Agfa and I can tell you without hesitation that both have irregularities with cutting mechanisms, lot number problems and slipsheet issues. It is a fact of life, and they all have it at some point.

When making plates, the goal is to change cutting blades before they wear. Based on Cutting blade manufacturer tolerances, but as all manufacturers, all cutters do not have the same wear, so again the goal is to change them before they wear, in preventative maintenance. However sometimes a defective cutter finds it way into the manufacturing process. For Kodak, for Fuji and Agfa.

One of the main problems is that when you order your plates, you are supposed to supply plate diagrams from your press manufacturer, if you haven't supplied them you should. if you supply standard measurements, those measurments are converted to metric because metric is more accurate and the machinery almost always uses metric. They then label the plates to that countries measurements. So a 21 3/8 is not really 21 3/8 it is the metric equivellent to the fourth decimal.

You should maintain the same principal to the equipment that uses the plates, stay in metric or stay in standard. I have seen people have their presses set in standard, their CTP in Metric and their benders in standard. Or any variation of the concept. Stay consistent throughout your shop to minimize all the potential problems that can arrise.

You should find out the measurment that is being ordered in metric. Then a .3mm or .5mm variation should not be a problem. They all have the tolerance, it is an inevitable fact of manufacturing plates.

Hope this helps.

I've had similar problems with Agfa in the past. The size was correct but the borders weren't straight but kind of curved. Agfa didn't accept our complaints because the faults were within 'their' tolerances. I can't remember what those tolerances were exactly, but they were huge imo.
If you ever have problems with the registry of your plates you should try this ; put 2 plates next to each other on a lighttable with the longest sides right next to each other. When the corners of both plates touch, you'll be amazed about the gap between the two borders somewhere in the middle of the longest side. This shouldn't be a problem as long as the size of the gap is allways the same at same position. And this is were it al went wrong with Agfa. The 'curves' along the longest sides of the plates were never the same causing loss of hours and hours of very expensive production time on the presses.
Later tests showed that every platemanufacturer has to deal with this problem but at least their 'curves' were more or less the same and didn't cause misregistration problems on the press. Modern presses don't expect faulty registered plates anymore and have limited their (expensive) abilities to correct this by shifting and tilting the plates on the drums.