Speaking of CAD, where to get accurate prints?

[John Coloccia]

If I produce something in Sketchup, for example, and I want it printed out full size, ACCURATELY, how do I get that done? Normally I embed a 4"X4" square somewhere in my drawing so I can measure that afterwards and I know if there's anything off, but I find that they're off more often than not.

[Ernie Miller]

If I produce something in Sketchup, for example, and I want it printed out full size, ACCURATELY, how do I get that done? Normally I embed a 4"X4" square somewhere in my drawing so I can measure that afterwards and I know if there's anything off, but I find that they're off more often than not.

John - I routinely have full-sized drawings of harpsichords printed from CAD files. Evidently, most printing establishments rarely print in full size and there is a learning curve - even for them. I use McGee-Cad Reprographics (http://www.mcgee-cadd.com/) in Greenville, NC. In the beginning, they too had trouble printing accurate full-sized drawings, but they figured out the problem. Occasionally, if someone new is doing the printing, the problem will re-surface. They've always been quite willing to reprint at no cost until the problem is solved. You can e-mail them your files and they'll mail your copies to you. I don't know if their software can handle .skp SketchUp files but it only takes a phone call to find out. The manager of their Greenville store is Michael Trivette. I'm sure if you speak to him you'll get the result you're looking for. By the way, I have no interest, financial or otherwise, in this company. They just do a good job at a good price (about $15.00 for an 8' long drawing - plus shipping).

Hope this is helpful,
Ernie

[John Coloccia]

Yes, that helps a great deal, Ernie. It's nice that they've already been through the learning curve so hopefully if I tell them what I need and why, they'll pay special attention to it.

[Matt Meiser]

Kinkos will do that too, but I can't speak to their accuracy. They take PDF.

It would probably be worth your while to create a standard object you drop into anything you have printed that has say a 4x4 grid with 1" lines so they and you can check for distortion.

[Jay Maiers]

I think the tougher challenge here is not the physical printing, but the output of the file in a usable format. From what little experience I have with sketchup, it's going to be difficult to produce an accurately scaled PDF.
FWIW, My best success involved importing the file into another CAD program (Rhino) and printing from there. Sketchup doesn't seem to want to print on paper (or to a PDF) that's larget than letter size. Perhaps there is a plug-in that will make printing a little easier?

[Wes Grass]

The other problem you may run into is that paper shrinks and swells. It may come out of the plotter dead on, but may not be a week or two later when you use it. Of course, that depends on how accurate you really need it to be to begin with. I think if you need something stable they print on mylar. And there may be better papers available now too.

[Ernie Miller]

Kinkos will do that too, but I can't speak to their accuracy. They take PDF.

It would probably be worth your while to create a standard object you drop into anything you have printed that has say a 4x4 grid with 1" lines so they and you can check for distortion.

I recently wrote a book on harpsichord construction. Included with the book is a full-sized CAD drawing of an instrument. One of my readers converted the CAD to a pdf and tried Kinkos - without success. The x-axis was fine but the y-axis was considerably off. It seems the key factor is not the printer or the file format, but the knowledge and experience of the man or woman doing the printing. He subsequently sent the CAD file to McGee-Cadd and the printout was perfect.

Ernie

[Chip Lindley]

The human factor in dialing in the printer to accurately reproduce X and Y axes is only one part of the accuracy problem. Stability of the sheet medium used for printing is the other.

Even before the advent of plotters or large-format inkjet or laser printers, sheet Mylar was used to preserve the accuracy of inked drawings. Mylar is very stable, unlike paper products--even Velum. No doubt, Mylar products are made for large-format printers. I bet it's expensive stuff!

[Ernie Miller]

The human factor in dialing in the printer to accurately reproduce X and Y axes is only one part of the accuracy problem. Stability of the sheet medium used for printing is the other.

Even before the advent of plotters or large-format inkjet or laser printers, sheet Mylar was used to preserve the accuracy of inked drawings. Mylar is very stable, unlike paper products--even Velum. No doubt, Mylar products are made for large-format printers. I bet it's expensive stuff!

No doubt, Mylar is the way to go for long term stability. In my case, the blueprint is cut up and used as a template for various assemblies so I consider the plan to be a one-time-use only proposition. I can't see how sheet stability can effect the accuracy of the original printout. If the printout is incorrect in the first place, Mylar will only preserve the incorrect drawing. Garbage in - garbage out. :)

Ernie

[John Coloccia]

Printing to mylar is an interesting idea I hadn't thought of. I've seen patterns cut from mylar, though.

[Frank Mussenden]

John PM me I can hook you up. Auto Cad

[John Sanford]

Every decent size city will have at least one legacy drafting supply/reprographics company like McKee-CAD that, if you can get a file to them, they can print it out accurately.

[Jay Maiers]

Another quick thought about templates: perhaps using a cnc router or a laser cut template would work? If you're going to use it several times, this might not be a bad option. If the build process destroys the template, it's probably not such a good plan :)

We cut crate stencils on our CNC router. Before we switched to this method, we had a guy that would laser cut them from a thin, flexable plastic. They were a little too fragile for our purposes, but I imagine that they'd work well as a template.

Also, I spoke with the head of the graphics company we use for the majority of our business. (I'm in the tradeshow exhibit industry; LOTS of graphics...). He said that there are several forms of media that should be more than stable enough if you want a printed template. I'm still waiting on the plotter folks to come out and do their demo; I'd expect they'll be out by the first of next week.

[John Coloccia]

Guys, this is all really great information and some great ideas. A laser cut flexible template is really sounding like a marvelous idea! I don't have the decoder ring for the industry lingo, though. When I look in the phone book, what magic words should I be looking for to have this sort of template made, or is it as simple as, "Bob's Laser Cuttin' & Stuff"? I guess what I'm asking is if there's a specialty I should be looking for?

[Dan Hintz]

John,

Send me an email (see my website from the FOTC link) and we can discuss what you want done.

[John Coloccia]

Thanks Dan. As soon as I have something drawn up, I will.

[Bob Lang]

Printing full size from SketchUp is no big deal, if you understand how the program works. You need to go to the Camera Menu and check Parallel Projection, and you need to be in one of the "Standard Views". The next steps are a little different if you're on a PC or a Mac, but you want to set the scale at 1 unit in the drawing = 1 unit in the model. SketchUp will automatically tile across as many sheets as it needs to. You may need to set the Printer Properties on your machine as well. Again this varies with different computers and printers but you want to find the controls for scaling, usually printers have a default of "fit to paper size" that you want to turn off.

If you want something on one big sheet, there are also a bunch of free programs available online that will function as a printer and create a PDF file. Set that up to a standard architectural size sheet and you can save a file that anyone with a large format plotter can print. Local copy places and office supply stores often have these machines. It may take them a while to find out where to turn off the "fit to paper size" scale function, but in my experience they won't charge you for their trial and error experiments.

There is a pretty good explanation of this on the Popular Woodworking Magazine editor's blog. Search on "Use+SketchUp+For+Full+Size+Patterns" and you should be able to find it. There is an even better, more detailed explanation on printing from SketchUp in my book "Woodworker's Guide to Google SketchUp", available from my website.

When I make a full size print for a template, I simply spray the back of the paper with 3M Super77 adhesive and either stick it to the actual workpiece, or to the template material. When you know how to generate a full size print it doesn't take much time or cost much to make a new one if you need it.

Bob Lang

[Pat Barry]

Bob, this is great advice. Your book sounds very interesting to me. I'm just getting started with Sketchup and see a lot of potential so good ideas on using it for woodworking design and documentation are what I'm needing help with.

[Bob Lang]

Thanks Pat,

I won't put a link in a forum post, but if you click on my name, then visit home page you can find more info.

Bob Lang

[Erik France]

It may take them a while to find out where to turn off the "fit to paper size" scale function, but in my experience they won't charge you for their trial and error experiments.This is most often the cause of improperly scaled plots that I see (granted that the maker got it right in the first place). I usually send PDF files out for reproduction, rather than plt or the original CAD file. You have complete control over the final output with PDF. If I'm sending them to a company or builder that I'm not familar with I always tell them "print at 100%, do not scale to fit."

[Nick Laeder]

Any construction plan room can do this. Printing to full size is the same challenge as printing to any set scale, and I get hundreds of sheets printed to scale every week. I'm not satisfied with Kinkos for their price and quality, but they've done it in the past. Just don't pay for it until it's right.