Vandercook 320G packing
Hi everyone! I’m hoping someone out there may be able to offer me some advice with packing my Vandercook 320G.
I’ve got a piece of cold rolled steel, 18 gauge/ 0.05” to make up for the galley width. I talked to a few print shops in my area about packing, and one printer I talked to only uses Mylar, (and swears by it) I thought I’d give it a whirl. So I have 18 sheets of 0.004 mylar on the cylinder, and still it doesn’t seem to be enough. I used that amount because I read that my undercut should be about 0.07. My undercut is not stamped anywhere on my press (it must be too old), so I’m left with trying to figure it out on my own… If my measurement is right (on my calipers) it seems like my undercut in 0.11. Isn’t that rather large?! I read that the 325A has an undercut of .105, and I’m thinking that mine might be close. Any recommendations for doing a hard-pack on such a large undercut? If I used 0.004” Mylar that I can find locally I’d need 28 sheets! Is that too many sheets? What would be some downsides of running so many sheets?
Thanks!
Kind Regards,
Amanda
Amanda:
There were Vandercook presses produced with several different undercuts for specific applications. If you send the serial number to Fritz Klinke at NA Graphics, he may be able to access the records he has from the Vandercook factory, and tell you exactly what the undercut was on that particular press.
In my experience polyester film (Mylar is a trade name) will work fine in multiple layers, but it can trap air between sheets in humid weather so you would want to smooth it down sheet by sheet to get the best fit. An alternative would be to purchase film of greater caliper to keep from having so many sheets. You could alternate paper and film and still have a very firm packing, that would eliminate the film to film contact problem. Many Art supply firms carry somewhat heavier film (.007”).
John Henry
Thanks John. I’ve emailed NA graphics. Fingers crossed that they will be able to give me an answer. Thanks for the advice!
-Amanda
When the cylinder is at the starting position at feedboard the packing depth should be stamped on the cylinder closest to you. In the manual is says .070. I use packing, typman and one sheet of mylar on the tympan for nice clean printing.
Casey
www.inkylipspress.com
Hi Casey.
Thanks for the comment. The undercut is not stamped anywhere on my press. I’m thinking that it must be too old or something. I saw that the manual said .070, which is why i tried using 18 sheets of 0.004… (together is 0.072). It really doesn’t seem to be enough. With my rollers adjusted to type high, the type gets inked nicely… however I need to use a whole whack of extra paper under my actual print to get an impression (like a good 1/8” worth of paper!). Do you use the packing and tympan sold from NA Graphics or something a little less expensive?
Thanks!
-A
I can’t remember- do you already have a bed plate in place on your press? It needs a .050 plate under the type or plate base and .070 of packing on the cylinder.
Daniel Morris
The Arm Letterpress
Brooklyn, NY
Is the press going off “trip” ok? It could be that the cylinder bearing doesn’t head back to the print position during the printing stroke.
That would keep the cylinder above the level it should be when printing, yet the rollers would be inking properly.
John H.
Daniel - yes, i have a 0.050 bed plate. I measured the undercut again last night to make sure I wasn’t loosing it. I’m measuring 0.105.. I put a straight edge across the cylinder bearers and measure the top of the straight edge to the cylinder bearer, than the top of the straight edge to the surface of my cylinder. The difference came out to 0.105.
John - Yes, it’s going off trip correctly. Thanks though.
Looks like I’m going to have to use some big packing. I’ve heard millboard could work. What do you think?
I appreciate all the help! Thanks!
The local university has a 325A with the a .105 undercut (I believe) the number is stamped into the groove at the user end of the cylinder. It’s hard to see and I didn’t spot it until a few years after acquiring it and donating it to the university.
When I first saw this press it had a rubber blanket as packing. These presses were made to proof newspaper pages, so maybe this deep, soft packing made it easier to proof a page from the paper.
NA Graphics sell some thicker packing sheets - up to .016 in thickness. I think you should aim to have fewer sheets if possible, but stick to rigid packing. The Kimlon and rubber blankets are good for printing flat from worn type, but are not good for printing with impression from plates.
http://order.nagraph.com/tympan-press-packing.html
Daniel Morris
The Arm Letterpress
Brooklyn, NY
Hi Dan
While I would agree that fewer sheets of packing is best, II don’t know that I would equate rubber blankets and Kimlon as the same. Kimlon is a rubber impregnated sheet for sure but it was recommended by Vandercook and is currently tooted as for older cylinder presses (such as the Vandercook). I would not want to print without it, I’ve always found that it assists in providing a very crisp, evened out, and clean impression, metal or photopolymer plates.
Gerald
http://BielerPress.blogspot.com
Thanks everyone for the helpful advice. :)
My Vandercook No. 17 has a deep undercut too, which I measured to be .105 although I was not able to find a stamp on the cylinder to confirm this. It came to me with a rubber blanket and has two sets of tympan reels so I strap the blanket down with a drawsheet over the first set and try to leave that as is, and then use the top set of reels for a more traditional type of packing. The results are less than ideal but that has more to do with lack of operator skills than packing, methinks! The cylinder is not a standard size so I have been cutting down larger sheets of tympan (and mylar for drawsheets) to fit, and It would require three sheets of Kimlon to equal the blanket thickness so that would get a bit too spendy for me right now. The blanket seems pretty old though, so maybe it would be worth it to replace, any opinions? Thanks!
The two sets of reels are for permanent packing and temporary packing. It is possible that the 17 had a canvas sheet as the lower permanent packing; it was commmon on earlier Vandecook galley presses. Vandercook later used rubber blankets in place of canvas, but both are soft but resilient materials that don’t beat down under what was then considered normal use. Normal use today is more abusive of soft packing.
Canvas huh? I do remember reading something about this, here on briarpress I believe. Curious to know why a soft packing would be considered advantageous. Does it make pulling a speedy proof easier with less makeready? Is the Kimlon harder than a rubber blanket? The blanket on my press brings the remaining undercut to .040, do you think a sheet of Kimlon would be of benefit in the second, temporary layer of packing? Trying to decide if it is a worthwhile investment. It is a real pain to try and wrangle all those layers and I try to keep changing the packing to a minimum. This has been a lot of trial and error (aided by the many informative posts I’ve found here), not least in that I only realized there was an extra-large undercut in the last year or so…boy did that explain a lot!