Biz Hub Pro C500 and Transparencies

[pspahr]

I've a customer who runs a good majority of transparencies form bypass 8.5x11 SEF. The jobs are usually between 10 and 50 prints with a 4x4 circle close to the center of the page. Each quadrant of the circle is colored: red, yellow, blue, green. Occassionally during the run the bottom portion of the circle will have a stretch mark running from left to right. It appears that the lead edge of the transparency is crashing into the fusing roller momentarily allowing the transfer belt to stretch/squash the image before it carries on. I've replaced the transfer roller/2 and the seperation charge assembly and it has minimized the problem a good deal. However, I don't believe I'm on the true track of whats up with the machine. I am new to the machine, and it's the only KM I'm trained on so I'm still learning as I go. Anyone else ever have this problem or have any idea what I should be looking for?

Hate to ask in such a noobish way but I am stumped

[minimerlin]

Is the customer setting the bypass to feed transparencies? They are special paper types and as such the machine needs to know what it is feeding.

[pspahr]

Is the customer setting the bypass to feed transparencies? They are special paper types and as such the machine needs to know what it is feeding.

Previously a technician was said to have set it up for transparencies but how he accomplished that remains in question. I'll take a look into it to see how it's set. Thanks for the response and idea, I'll let you know what I find.

[pspahr]

SOLVED!!!!!

Today I ran the machine after replacing the registration roller assembly. The problem minimized after the installation but didn't go away completely. I noticed that the image on the prints that had the stretch/squash issue were overall about 1/4 inch higher on the page than the prints that were normal.

So, i increased the spring tension on the upper steel registration roller to keep the transparencies from occassionally pushing past the reg rollers. The oilite bushings for the upper reg roller were slightly worn but not visually noticeable but I've ordered them so I can replace at a later date.

Also, interestingly, this model doesn't support the use of transparencies!!!! Checked the specs in the manual and it clearly states not to use them. Some jackhole at our company found some that would work, though, and so now I'm stuck with this machine for 2 more years trying to patch it up enough so it feeds transparencies (of which they run 8k to 12k per month)......The machine was 1 year onsite in April and currently has a total of 480k. This means about 30~40k per month and until now it's run pretty flawlessly. I was determined to hate Monicas after a brief stint working on some older model Konicas but so far I can't really complain about this box or the newer offerings like the 550/650.