Awhile back, I posted a "HowTo" thread about submitting a design to Armattan Productions for cutting. ( http://intofpv.com/t-design-your-frame-a...ill-cut-it )  I mentioned at the time that I used QCAD Pro for my 2D design work, but didn't go into much detail. In this tutorial, I will go into some of that detail and show you how to get started with QCAD to create your very own quad design!

QCAD is a very powerful CAD program.  There are three versions:  There is QCAD Professional (which is what I use),  QCAD/CAM which adds a CAM layer to QCAD Pro (in case you have your own CNC machine), and then there is QCAD Community Edition which is free and Open Source.

I will use the community edition of QCAD for this tutorial, so you can try it out without investing any money in it.  If you are new to CAD, the free edition is probably sufficient for most of the things you will want to do for a long time.  To see the differences between QCAD Professional and QCAD Community Edition, see: https://qcad.org/en/qcad-documentation/qcad-features (italicized features are only available in Pro).  Actually I haven't used many of the "Pro" features myself.

Important note:  Regardless of your platform, you will want a three-button wheel mouse to use QCAD.  (It's nearly impossible with a touch pad or a Mac magic mouse!)

When you download QCAD, it actually includes a trial version of "Pro".  The Pro features are active for 15 minutes and then you have to restart.  We will make it the "Community" version by simply removing the "Pro" features.   So let's get started!

Go to https://www.qcad.org/en/download and download and install the version of QCAD for your machine.  I use macOS Sierra, so I will choose that one.  (Note: if you use Linux, your distribution may have package for the Community Edition already set up - so use that and you can skip disabling the Pro features.)


After you've installed QCAD, start it and make some initial settings.  I suggest changing the "Unit" to Millimeter (and I will change the paper size to ANSI A - Letter).  I suggest leaving the "Background Color" on Black.


Select OK and you will get the screen shown below.  Now we need to disable the "Pro" features by clicking "Remove".  You may get a dialog window asking you to remove some plugin files (you do on a Mac).  Locate these files and delete them. (On a Mac, the files are located in the Contents folder of the QCAD.app in Applications.) When you remove the files, the program will close.  When you restart it, it will be the Community Edition running.


When the program is restarted you may have two windows.  You can close the "Property Editor" window.  I like to resize the main window for my screen, and make the "Layer List" tab narrower (by dragging the edge of the document window to the right a bit).  What I end up with is shown below.


If you "hover" your mouse over the various tool icons, you will see what each one does.  One of the most important tools is the "Reset/Idle" button (arrow) in the upper left.  If you are working with any other tool, and want to do something else, click the Arrow to end the previous operation.  Clicking on any of the tools on the left side of the screen, will take you to a sub-tool menu for that tool.  (In the image below, I've circled the tools I use the most when designing a quad.)  Once a sub-tool is selected, the icon below the reset/idle button will show the active tool.  The other "tab" I use a lot is the Layer list on the right side of the screen.


On to the drawing area.  The red "cross hair" (indicated by the green arrow) is the origin (0,0) of the drawing area.  I like to center my quad designs at the origin.  To move the origin to the middle of the drawing area, hold down the middle mouse button (wheel) anywhere in the drawing area and drag.  Notice the grid numbers at the top and left of the screen.  These are the unit markings (millimeters in our case).  The actual grid is subdivided into units of ten.  To zoom in or out, roll the scroll wheel on the mouse.  (As you do so, you'll see the numbers expand or contract and the numbers change as well.)  While drawing, you can actually zoom or reposition the drawing area with the mouse wheel while a tool is selected.  In the image below, I have moved the origin to the center and zoomed out to give me a drawing area of about 300 by 150.


To illustrate how I use the tools, I'll design a simple unibody quad laid out as an X-style frame.  Since I mainly want to illustrate using QCAD, I'll keep the design simple and design it around standard components (22xx motors, 30A escs, FC with 30.5x30.5 mounting holes, 4s 1300mah battery, 5" props).  So let's look at the dimensions needed to accomodate these.

• Motors: Outer diameter - 27.9mm, Mounting hole diameters - 16mm and 19mm
  
• 30A escs: Typically around 28mm x 13mm
  
• FC: 30.5mm (we'll focus on the mounting holes and allow enough space for the FC)
  
• Battery: Typically around 75mm x 35mm
  
• 5" props: 127mm (and we'll add 10mm clearance between props)
  
• M3 hardware: we'll use 3.1mm holes
  

In the video below, I show one way to layout the components using QCAD, and then I create a (very simple) design around the layout.  (Important Note:  This is a tutorial about using QCAD, NOT about designing a quad.)


I am happy to try to answer questions about using QCAD (if I am able)
Thanks for reading/watching!

Awesome Scotty!
I have been wanting to design my own frame for a while now. Not sure if my Netbook will handle it, but now I know where to start.

Thanks Stephen! 2D CAD programs are pretty resource light. I bet your Netbook will do fine. Let me know how you make out. (Don't forget the wheel mouse!)

Nice write-up.

Ooooohhh...Thanks for this! Now maybe I can design my own 3 inch HDPE frame!

(14-Jun-2018, 03:52 PM)voodoo614 Wrote: Nice write-up.

Thanks voodoo!

(14-Jun-2018, 04:15 PM)Sugs Wrote: Ooooohhh...Thanks for this!  Now maybe I can design my own 3 inch HDPE frame!

Be sure and share your design here when you do.  Do you have a CNC mill to cut HDPE?

(14-Jun-2018, 06:13 PM)sloscotty Wrote: Be sure and share your design here when you do.  Do you have a CNC mill to cut HDPE?

I wish, but no.  I was going to try and find someone who does, maybe online.  I do have a friend that is in the plastic business, he might.

Very nicely done Scotty!!

(15-Jun-2018, 07:29 PM)sirdude Wrote: Very nicely done Scotty!!

Thanks Chris!  (I can't believe no one has commented on my very last photo though....)

(15-Jun-2018, 08:26 PM)sloscotty Wrote: Thanks Chris!  (I can't believe no one has commented on my very last photo though....)

Frankly, I didn't even see it.  is that the one you designed and had cut?

(15-Jun-2018, 11:24 PM)sirdude Wrote: Frankly, I didn't even see it.  is that the one you designed and had cut?

Yup, but it was the 3rd (secret) one - look familiar?......

(16-Jun-2018, 12:23 AM)sloscotty Wrote: Yup, but it was the 3rd (secret) one - look familiar?......

Yes it does, nice job Scotty!!

You'll have to call yours FSF 

Actually, the working name is "BFQ"...


(Now, that's gonna get irritating...)

(16-Jun-2018, 01:18 AM)sloscotty Wrote: Actually, the working name is "BFQ"...

(Now, that's gonna get irritating...)

BFQ......hmmmmm....let me guess.........