Not all litho grade papers are made to be converted into envelopes. In general, paper with a thickness of between .004 and .008 will readily fold on an envelope machine when proper grain direction is observed. This holds true for both coated and uncoated sheets. Some sheets, both lighter and heavier may be foldable, but samples should be tested before going ahead with your project. Envelope blank size and style will determine sheet size requirements. Multiple-up layouts will either have the blanks nested, in the case of diagonal seam envelopes, or step and repeat, in the case of open-end and open-side (booklet) envelopes.
Incorrect grain direction can make a converting project impossible to fold on an envelope machine. The reason for this is that envelope machinery is required to fold paper in two directions at very high speeds. The side tabs perpendicular to the flap are “plow” folded on the machine and must fold with the grain of the paper. The envelope flap and bottom seams are “force” folded in a buckle plate with enough force to fold against the grain. Envelope in-line scores are not channel, like on a letterpress, and therefore cannot be plow folded consistently.
Accurate die “Tic marks” are essential so that our cutter can place the envelope die in the same position on your press sheets each time to maintain consistent registration on your finished envelope. “Tic marks” will always be positioned in the shoulders of the envelope blank on either side of the flap. We’ll use as small a dot as possible and back it out of the corners by 1/8” inch so they will be removed with the trim in the cutting process. “Tic mark” position is always indicated on the provided layout.
ADJUSTABLE CUT JOBS WITH SQUARE FLAPS AND SIDE SEAMS DO NOT REQUIRE TIC MARKS.
Envelope layouts created by your design or pre-press departments may not allow us to convert your project into quality finished envelopes. While we have an enormous array of standing envelope dies, each has fixed angles, flap sizes and shapes. The layout process needs to begin with PEC (Piedmont Envelope Converters) providing you with an electronic layout of the actual die to be used in the project from our die inventory, or a new die that you have ordered from us to be made especially for your order. In either case the positioning of the blank(s) on your press sheet must be established by PEC so that the envelope blank can be cut either by hand or on a programmable Hydraulic Press. You then place the art on the blank(s) with the required bleeds if necessary and we take it from there. Repositioning of the blanks must be avoided if the job is to be converted accurately with the minimum paper waste. Computer design software allows you to draw layouts with highly accurate measurements to the 1000th degree. Unfortunately, our converting capabilities only allow us to adjust our sizing up to a 16th of an inch. Please keep this less than perfect measurement capability in mind when designing your layout parameters. We cannot be responsible for super critical (perfect) bleeds and borders or copy which crosses folds or seams. A 1/16 to 1/8 inch variation may occur when converting.
Glue may not stick through ink or coatings. Please hand-fold a proof sample before plating, to make sure your knockouts are covered by the flaps after folding.
please enclose a folded dummy sample with your order to assure proper handling of your order.