what program to print from the gives me an accurate print?

[Frank Burroughs]

Epson EcoTank 4-color A4 Ink Tank Printer L121 just bought off Ebay.  I wonder what program gives a 1:1 print.  LibreOffice draw and GIMP are my graphic programs.  Right now masts and spars are what is being made.  Later much more will be drafted.

 

So, what program to print from the gives me an accurate print?

 

ps.  You guys have to stop me from spending money.  I private tutor when money gets low.  Do you know how mean people get when they hate math!

[thibaultron]

Most graphics programs allow you to scale a print in the X and Y axis. As long as you know a dimension in each axis, you can correct the print. Place marks in each axis a known distance apart in your drawing. Then print it at 100%, and check the finished print. If the dimensions are off, use the scaling to correct, and make a final print.

[Dr PR]

Many printers do not print 1:1 automatically (be sure "Fit to Page " is disabled). Even though you may be using a CAD program and draw things very accurately the printer may screw it up. Draw a line* that is about as long as the long dimension of the paper you are printing on. For example, a 10 inch line on a normal 8 1/2" x 11" letter size page. Print it and measure it to see if the printout is the right length. If not, determine the percent error and use the scaling factor in your computers print drive to correct it. Print again and check. Be sure to check both X and Y dimensions on the paper.

 

For example, I had an expensive Hewlett-Packard color laser printer that always printed at 95.877% of full size, so I set the print scale to 1.043:1 and it printed correctly.

 

On the other hand my current cheap Brother color "laser" printer prints exactly 100% so I don't need to correct the scaling.

 

* Note: It would be better to actually draw a ruler with multiple equally spaced marks so you can be sure the printer advances the paper correctly, and doesn't screw up the spacing along the page length.

 

****

 

If you create a PDF drawing you can use the free Acrobat Reader program. The MSPaint program that comes with Windows will also print most bitmap file types (Windows/System32/mspaint.exe) and you can use it to scale drawings. Your LibreOffice Draw and GIMP programs should be able to print anything you create with them.

Edited April 22 by Dr PR

[iMustBeCrazy]

55 minutes ago, thibaultron said:

Then print it at 100%

In Windows for the L121, when the print dialogue box comes up click on the 'more options' tab, select 'Reduce/Enlarge Document and set the 'Zoom to' percentage (jeeeeeze, whats with Epson, everybody else calls it the scale).

 

[Jaager]

It is the scanner that alters.   The printer replicates what the file saved is.  Just as long as the "fit to frame" box is not checked  in the print command window. Just as long as the page/canvas in the graphics program document file in use is exactly the size of the paper that the printer is set for.

 

I have a canvas as a stock document that I always use. It is as close to being exactly 8.5x14 as I could make it.  For everyone else, I guess 8.5x11.  I lacquer coat my patterns, doing this is not being a fun thing, I aim for fewer pages, thus the larger page,  an expensive choice.  There is a huge difference in price per ream.

The numbers that I came up with:  8.5x11   2197 pixels x 1701 pixels  and   8.5x14   2796 pixels x 1701 pixels.

I added a scan of a 15cm clear ruler.  Metric is easier for the scale adjustment math.    I selected the background and CUT, so that the layer is transparent except for the scale hash marks.   I scaled it in my graphics program (Painter - because I already had it) until a printout was identical to the original.  For a long time, I included the 15cm ruler bar at a horizontal edge and a vertical edge of every page as a check. 

 

For a home scan, the first thing to scan is a clear background ruler.   Once you determine the scale factor adjustment of your scanner, it will be a constant for that machine.

For outside scans, there must be a known distance on the page. 

I do all of my lofting at 1/4" : 1' .    I found a 1/4" scale on the Web.  I made it its own layer.  I selected the background and CUT, so that the layer is transparent except for the scale hash marks.

I had to adjust the scale of the layer until a printout was identical to the 1/4" scale on my triangular architects ruler.

So, every outside scan is has its known distance compared with my 1/4" layer.  When my scale adjustment has it match what I want it to be, every print has bee accurate.

When you adjust a scan, ALWAYS do it on a duplicate layer. Do not risk the original.  Chain adjustments can get out of control very rapidly.  If the first factor is not enough or too much, delete the duplicate layer.  Make a new duplicate and adjust that.  Write down every new number of scrap paper,  your memory will fail you. 

[druxey]

Don't forget that paper itself can change dimensions with humidity levels, and not in the same proportions along x and y axes!

[allanyed]

7 hours ago, Dr PR said:

Draw a line* that is about as long as the long dimension of the paper you are printing on.

Similarly you can draw a box that is any given dimension in both the x and y axis such as 4 or 5 inches (100 or 150mm) somewhere on the drawing that you want to have printed.  Once the drawing is printed, check the length and height of the scale box with a vernier caliper to confirm the printed plan is accurate.  For larger drawings I like to use architectural engineering printer shops and ask them to check the scale box on the printed sheet.  They have rarely had to make minor adjustments.  I have also gone to Fedex offices that have large format printers.  More often than not they have had to make small adjustments to get accurate results which they were happy to do. 

 

For those that do not do their own drawings but get prints from RMG and other sources, the copies are suspect as the original plans are often distorted to some degree which is not surprising after a few hundred years.

 

Allan

[Frank Burroughs]

Excellent advice all!  Good to know the program is not as important as scaling the printer.

 

Another question is about storing the prints.  Right now my prints are of masts and yards.  They will fit in a regular binder.  Will later prints of scratch built ships also fit in a regular binder?  No place to put up drawings in the house.  However, the garage could fit a drafting table in the future.

[Scottish Guy]

4 hours ago, Frank Burroughs said:

Another question is about storing the prints.  Right now my prints are of masts and yards.  They will fit in a regular binder.  Will later prints of scratch built ships also fit in a regular binder?  No place to put up drawings in the house.  However, the garage could fit a drafting table in the future.

 

I store bigger prints always in paper shipping tubes (can´t afford one of the drawer units for A1 prints like architects have). Is a good way to store them and to protect them. Folded plans often get damaged because of the kinks where it is folded, rolled into a tube this can´t happen and they last longer.

 

Micha

[mtaylor]

Micha is spot on.  Back in the day, all drawings were either rolled into a tube or stored flat in large drawers.  One place I worked weve hung the ones currently in use on a clothes line stretched in the either the archive room or the copy room.