Inking problems, sp-15
Hello All. I’m having inking problems with the form rollers on my Vandercook SP-15. My rollers are new from NA Graphics and the durometer is perfect. The problems are:
1 - The height of the form rollers change when the press switches between print and trip.The following link to my flickr site illustrates this point, although we had re-adjusted the bearings since taking these photos and now the rollers lift at the end of the bed when they are tripped.
http://www.flickr.com/photos/45293278@N00/sets/72157617411356816/
2 - The form rollers seem to sit too low and the screws don’t seem long enough to give us the correct clearance. The press has a galley bed and it’s possible these were not the original screws. We measured the length of the screws in the bearing blocks and they measure 2 5/16″. What should the length of the screws be?
Any suggestions are much appreciated!
Hi Rachael! I have the exact same problem!
Did you ever get it resolved? If so, how?
Thank you!
Grendl.
Hey Grendl, if the rollers are at different levels on trip and print, the carriage is misadjusted. Serious fine tuning of all carriage bearings is needed so it is parallel and also at exact height.
I don’t think roller adjustment screws would be different from .918” and .968” models, just one or two threads of difference.
-Eric
eric,i am helping grendl with this problem. can you confirm that my way to solve it is right? sorry its a long post.
1. step: i will measure the diameter side to side on the back and on the front (excentric) top rollers. they should be the same side to side.
2. step: will loose all 4 bottom excentric rollers, and the front top excentric rollers. so they can be turned by hand and have the biggest distance to the under rail.
3. step: put the press in print, the weight of the cylinder will touch the cylinder bearers to the bed bearers and keep it there. additional i can clamp the carriage down to the bed.
4. step: may be surprising, but i want to adjust the front top excentric roller first, so the whole carriage, or better the sides of it is paralell to the bed. double check with a level under the sides. at this point i am sure we dont need spacers anymore and the adjusting screw is long enough. the rear top rollers are fixed, so adjusting the front top roller with its excentrics on both sides should bring the front deep enough. test with the rollers adjusted in print and in trip. cross the fingers and hope‚ it will be the same. of course at this point we cant do a strong impression cause the lower rollers dont hold the cylinder down.
5. step: adjusting the impression rollers, same as i did it on my press. i put some stripes of a coca cola can (4 thousands) on the bead bearers, roll the cylinder in print over it and adjust all 4 excentrics of the lower rollers. this might take a few trial and error.
Well, I haven’t adjusted VDC eccentrics in 15 years, so I am a bit hazy. Everybody I know has a different method, but I do find yours a bit confusing. I don’t think placing spacers between the cylinder and bed bearers is best. When I got an SP-20 in the early ’80s, Vandercook was still in business and their tech support told me to use .003” feeler gauges between bearers and bearings, top and bottom, to an even pull.
For this I found 6” feeler gauges much better than shorties. Is there still a Flea at the Coliseum or Ashby BART? Oughta find a cheap set there or eBay.
eric, thanks for your fast response, gives me something to think, will be out tomorrow, so i will write about my thoughts more in detail on the weekend.