We are fairly new to working our T platen windmill having previously always printed on our C&P oldstyle. When we are printing a ink heavy image on the C&P we would double ink it before creating the impression to allow for good ink coverage. How can we achieve a similar result on our Windmill? We have upped the ink and our first print is fine, but the subsequent print comes out too ink weak. Any suggestions on how to tackle the problem without having to double ink and print sheet per sheet as we are doing now?
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The C&P has a slight advantage over the Heidelberg Windmill in that it has either 3 or 4 inking form rollers which allows carrying more ink to the form than the two contacting form rollers on the Windmill.
You need to use all the techniques available if the images contain large solid areas of ink coverage.
Make certain you have the distributor roller in place and the steel rider roller on top of it. If you have the rider which fits on top of the form rollers, make sure it is in place and is properly adjusted (see manual). By using all these rollers in the ink chain, you have a lot more ink being moved and available than if you are just using the two form rollers and the ink drum.
There will be more rollers to clean, but well worthwhile in terms of even ink distribution without ghosting.
You may well be doing this and still not have good coverage, in which case you may wish to pick an ink with greater pigmentation.
The sheets can be skip-fed on the Windmill, to achieve the same results that you get on your C and P. There is a bit of a rhythm to get used to, but you can alternate tripping the sheet suction, and the impression lever in a certain pattern to allow the form to double ink between each impression. I occasionally do this on a larger image/solid, and it works quite well. Perhaps this is what you are saying you are doing already, and are wondering if there is a better way? I find that this is often the best solution.
good luck :)
Printing heavy solids in a windmill is a challenge. You say you are double inking to increase ink coverage. If you are getting good results and the print is clean I think you are in the right path. Only that you are taking longer to accomplish the print, which should be contemplated when writing the invoice to your customer.
As this press has only two form rollers, plus the little metal roller that is mounted in between —if you have that roller it helps a lot. I know that roller to be called “ghost remover”.
I wouldn’t recommend doing that on this press, unless you have no other press and have to reinvent the wheel to get the job done —seems to me that is exactly what I do sometimes to get a job printed.
Adjust fountain blade to get more ink. Try rubber blanket material under tympan. Also 2 passes if using guides. It doesn’t hurt to check the manual about printing heavy solids ie ink mix and underlay.
Thankyou all for your help and comments! We have seem to have got a good result and have mastered the art of alternating the suction and the impression lever. Takes some coordination, but is certainly working well for us once we get in the rhythm!
Thanks all for your help :)
I see that this issue seems to be taken care of, but I am interested in this “skip-fed” method. Sometimes a double hit is in order, but what about just running it through twice?
I come from running offset presses, and the bead of ink you set at the fountain will determine the coverage and consistency of the run. It’s a beautiful thing when you tune your press just right.
BeSpokePress- when you say you “upped the ink” did your mean opening up the keys? I would think having a bigger bead in your solid area would solve your dilemma.
You also might want to try the adjustments for the rails. The ability to move your form rollers closer or further away from your form can go a long way.
Thanks for letting me revisit this- all I can picture is you guys throwing that lever back and forth after every sheet - hoping there is a better solution!
There are times when printing on leatherette type stock and trying to get coverage that I can’t increase ink flow due to smearing. Double and triple rolling works well. Of course this is not something to do if you have a large job. Usually it’s 100 copies or 200 at the most. RREEBB
make the ink thinner use van son SMOOTH-LITH.
Using the guides and running the sheets a second time is a great option on the Windmill. I’ve run halftones this way and got dot perfect registration.
(See flickr links below)
All the other suggestions are also great, but the ‘skip’ feed is something I would do only with great muttering under the breath or outright cursing ;-)
No reason to skip-feed the windmill if you are using the guides for registration. I suppose on a glossy stock liable to offsetting, you may not want to grab the stack and run it right through again, but on all the paper I like to use, offsetting is not really an issue. I’ve run three and four colors through all on the same afternoon, same sheets, one right after the next. No offsetting unless the coverage is extreme and the ink is too heavy…
See various examples at flickr:
Ivy Place - Halftone double-bumped - Strathmore 110# Writing Cover
SlowPrint "flywheel" cards on Copperplate Etching 300gsm
An offset press operator told me to mix the ink with opague white as it doesn’t affect the color but helps the ink carry better. The color does look different on the rollers but not on the paper. I hesitated at first but finally tried it. It worked. It may help your problem. Ron
Just a thought, did you check your roller height? Sometimes a bit of packing behind the chase works wonders. Other times I’ve used a bit of phenolic board on my platen depending on the stock I’m running. It’s wrong but it gets the job done fast and clean.