Intro: Technique: Digital Fabrication by Hand
For the other 99% of makers, here's an instructable on how to make things that are just as complex and precise using tools you can find at any hardware store, and templates you can print at your local print shop.
A few of us (some college students, people who live near a coop shop like Techshop, Instructables employees...) have access to CNC machines. Laser cutters, CNC routers, water-jet cutters, and other CNC tools let us design complex geometry and produce the parts quickly and precisely.
To demonstrate this handy technique, I decided to make a laptop stand for Wilgubeast, because he's a nice guy, he needed one, and he can't be bothered to make one himself.
Step 1: Tools & Materials
• Hand Drill + Bits
• Wood Files (rounded and flat edged)
• Sanding Block
• Rigid straight edge- I used a level.
• Pressure Clamps
• 3/4" Plywood (18" X 24" panel)
• Printed paper template
• Spray Adhesive
Step 2: Scan the Laptop
For this example, I'm going to make a laptop stand for Wilgubeast, because he needs one and he's to busy to make one himself. And he's a nice guy.
To get a (close enough) approximation of the measurements of his laptop, we just scanned it on the office scanner. There is no shortage of 3D models of the Macbook Air that you can download, but a scanner is a good trick for getting fairly accurate orthographic images of objects that you can use as a guide for making things in 3D.
I'm using Fusion 360 because it's free (for 1 year with an "Enthusiast" license after a 30-day free trial), and it's got all the tools we need to make this project work.
Step 3: Design in 3D & 2D
First I brought the scan of the laptop into Fusion 360 as an attached canvas. Having measured the length of the laptop, I was able to scale the canvas to the correct size. Since the object is a rectangle, it's easy to measure and create in 3D manually, but I wanted to get the filleted corners to match on the wood base, so the background image helped a lot.
Fusion 360 is free for students and hobbyists, and there's a ton of educational support on it. If you want to learn to 3D model the kind of work I do, I think this is the best choice on the market. Click the links below to sign up:
I use Fusion 360 almost exclusively for furniture and product design projects now. It's fast, stable, stores everything in the cloud, has mechanical assembly and parametric tools, and the new release is FREE INDEFINITELY! Start the product as a 30-day free trial, then when your trial is over select "startup" as the license type and you won't pay a dime until you become your own company and make lots of money with it.
It's important to always check the thickness of the panel material you intend to friction-fit. In this case, the 3/4" plywood is actually .72" thick, so the objects in the model are designed accordingly.
My workflow for this kind of thing goes something like this:
First, make the overall shape of the most important things without any detail. In this case I started the simple rectangular panel with filleted corners.
Second, move down the hierarchy of the the structure and get the basic shapes of those parts worked out. With this project I made one of the legs and mirrored it along the center axis of the model.
Third, work out the intersections between the components. This is where I figure out what each part will be shaped like and how it will interface with the whole. In this step, it's really important to think about how you're going to put the finished piece together- if you're not careful, you'll end up with tabs and slots that fit together in an impossible way in real life. This is also the step where I make sure the structure of the object will be rigid when it's built.
Fourth, add all of the finish details such as cutouts, fillets, etc.
Once the 3D model is done, I created a new sketch from each part face in Fusion, then projected them to the horizontal plane for use in a printed template.
Step 4: UPDATE: Make a Full-Scale 2D Template in Fusion
Please follow the link below to the screencast recording demonstrating the process of making a 3D assembly in to full-scale 2D templates for cutting.
Step 5: Using Templates
When cutting anything with a freehand saw (like a jigsaw), the best results you can get come by using a rigid guide clamped to the work. In order to be able to use a rigid guide in conjunction with printed templates, I measured the offset from the edge of the jigsaw blade to the edge of the base. The dashed lines you see in the template are for the placements of the rigid guard and ensure straight, accurate cuts. Guides obviously won't work for the curved sections, you have to eyeball those and go slowly.
This project is small, so the plywood size and template size only have to be 18" X 24". Any print shop that services architects and the building trades will have plotters that can print 4' X 8' sheets and larger, which is often necessary if you want to minimize waste on a larger project.
With a little spray adhesive, just stick down the template and smooth it out with a squeegee. Once this was done, I started clamping the level and getting the big cuts first.
Step 6: Cut Out the Pieces
With template fixed, I used the jigsaw with the guide for all of the straight edges, then without a guide for the curved edges. For tight curves, it's important to make several perpendicular cuts to keep the jigsaw from binding as it turns the corner.
Step 7: Inside Cuts
Inside cuts are the tricky part. These are done by drilling pilot holes that touch the edge you want to cut, then using the hole as a starter for the jigsaw blade.
I've labeled the diameter of the fillets on the inside curves, one's 1/2"Ø and the other is 1"Ø. The triangles at on the inside of the curves show you where to place the center of the drill bit.
The square holes that connect the legs to the base are especially tricky, but the same technique works here.
Use a file to clean up the inside holes once they're done, they need to be particularly straight for the pieces to friction-fit.
Step 8: Put It Together
Since you're using hand tools, there will probably be some adjusting that needs to be made. In my case, the male ends of the cross-brace were too wide by about 1/16", so I had to take those down a bit with the file. It's also a good idea to put a slight taper on the ends of all male-ended tabs to keep the veneer from delaminating when you force the parts together.
Using a rubber mallet, the pieces fit together snugly and stay put
Step 9: Finished Product
The finished product looks pretty clean, and it's very sturdy. Wilgubeast has a standing desk and a wireless keyboard and mouse, so he needed a stand that would prop the laptop up as high as possible.
It's awesome having all the space-age robots at the pier to do our fabrication bidding, but with a little patience, there's very little difference in the kind and quality of work you can produce. Don't be intimidated by complex geometry! With this technique, you can cut out just about anything.