Missing Microdots

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Missing Microdots

Postby jrowe » Sun Aug 23, 2020 3:30 pm

Hello, I am interested in hearing any techniques/tricks our Plate Mounters use to mount plates with missing microdots. I have an old Heaford Viper and
an newer AV SAMM 2500 mounting machine. The SAMM 2500 is used about 90% of the time. Looking forward to hearing everyone's response.

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Re: Missing Microdots

Postby longtimefan » Mon Aug 24, 2020 3:31 am

I've determined where the micro dot should have been and used a needle point to make a hole
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Re: Missing Microdots

Postby timer1 » Mon Aug 24, 2020 5:12 pm

Why are your microdots missing, are they just worn out? We had to increase the size of our microdots because they were leaning. A technique I used to use was to lower the camera a bit to focus on the base of the microdot. This will get you going but in reality new plates should be made.
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Re: Missing Microdots

Postby jrowe » Tue Aug 25, 2020 5:34 am

Thanks, for the reply's. The microdots sometimes accidentally get cut off in the press when the pressman are removing plate lifts. We have also seen new plates come in without microdots.
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Re: Missing Microdots

Postby lavoie » Fri Aug 28, 2020 1:47 am

If you are printing a single plate, then using a straight line will do. If you are printing multiple plates, printing in register, that is a bit more difficult. The stagger, if you have one, is going to be an issue. I have found that placing the plate without dots on top of a plate with dots, in register, making your own dots as close to vertically perfect as possible and connecting them with a line (fine tip) as perfectly straight as possible will get the job done. If it is only one of the plates in the set, mount it last as you will be moving the cameras. The more cameras the better. I always kept the drive side dot camera stationary for every plate and every job to ensure horizontal register is accurate. All other cameras can then move on the X axis (left to right) freely as they only hold the vertical register.
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