Thread: My 3 axis skull...in progress

Tweet

The screws are counter sunk and are towards the back of the skull. I plan to have a wig on one and hats on the others, so for me, they will not show. You could fill in over the screws with some wood putty or even spackle, or just paint the screws to match the skull color. It shouldn't be a problem.

It's much more of a challenge to make the line where the skull cap is cut not be noticeable.

Yes, the small armature is steel, but aluminum would also work fine. I think I did say it was aluminum at the beginning of the thread, but I was wrong. Don't think it makes a difference. It is not under any real stress. If you use aluminum, just be sure it's thick enough to be rigid.

ok cool.. thanks.

Yes the line on the skull seems to be the hardest to hide....

ya i was thinking alum might be easier to cut also. I'll find out anyways.

Speaking of Aluminum, I did use some here for the clamps that hold down the jaw servo for each skull.

First, since I did not cut a slot into the lexan plate, I had to shave off the mounting brackets on the side furthest away from the servo gear on the servo which will be controlling the jaw motion.



Then, I had to file down the stub that was left so the servo will sit flat on it's edge



Then it was time to make the brackets:



I started with some strips of aluminum I cut out with a hacksaw...(new blade this time)

Then I measured out the dimensions of the servo casing leaving a half an inch on each side for the 'feet' of the bracket.



I cut off the extra length with the hacksaw, then bent the aluminum strips on the marks I made so they would fit tightly around the servo. Here's what they looked like:



I checked them all by fitting them around one of the servos like so:



Then I drilled out the mounting holes. I used 4-40 screws again here to hold the brackets down, so use an appropriate drill bit for the screw you are using. Remember earlier when we made the lexan plates we tapped these holes for a 4-40 screw.



Finally, I mounted the bracket over the servo on the lexan plate.

Here's a couple shots at different angles:

I thought I should take a minute to document how much money you might be spending to duplicate this project.

First, I will list a bunch of misc. items that I did not pay for, because either myself, or my friend with the machine shop had laying around, so I didn't buy them, and I am not sure of the cost.

These items are as follows:

Tools - Including hacksaw and blades, heat gun, drill press, band saw, lathe (or the cost of hiring a machine shop) as well as standard tools, like screwdrivers, plyers, cutters, a vise, etc.

Hardware - Extra pieces of steel, aluminum, welding wire, Threaded rods, nuts bolts and screws, stain and paint, and whatever material you will use for the skull's body and clothes and a wig or hat if you decide to use one.

A computer to run it all. (I did buy a dedicated machine for this, but it was an old used one from ebay for about $50.00 plus shipping. You may have an old one laying around.

Wire to extend all the servo wires with to connect to the controller board. (I also bought multipin plugs and jacks to make the connection modular)

Lights and a kit 74 or similar board if you plan on using it to enhance your setup. Cost will depend on how extravegant you plan to get.

Now for the tangible costs.

First, the skull itself. The Pirate Skull from Lindberg is between $15.00 and $20.00 at most retailers. We'll go with $20.00 because you will probably be paying shipping as well...so:


skull - $20.00
5 servos - $70.00
Sheet of 1/4" Lexan - $18.00
Rod End - $9.00
Servo Linkages - $4.50
Bag of wooden balls from Michaels to make eyes with - $3.00
Brookshire Software's VSA - $55.00
Lynxmotion SSC-32 Servo Controller Board - $40.00

...not letting your wife find out how much you spent - Priceless!

Total cost for one skull like the one I am detailing in this thread not counting the misc. materials and tools mentioned above: $219.50


I wanted you to be prepared for the costs involved before starting.

I am buliding 4 of these suckers! Of course, I only need to include the cost of the computer, VSA software, SSC-32 borad, kit74 board, sheet of lexan, etc once. They will control ALL the skulls, so the main expense for each additional skull is the servos, and the skull itself.

Hope that doesn't scare anyone away! I know we don't scare easily around here.

It's an investment! And you also need to get the beefy power supply for the servos.

Forgot about the power supply!

I bought a 5 AMP 5 VDC supply on ebay for about $40.00 after shipping.

Actually, it has one 5VDC 5 AMP output and 2 adjustable 2 AMP outputs - (0-12VDC)

...not letting your wife find out how much you spent - Priceless!

Or husband...hehehe

Hey HalloweenBob... can you let us know what Power Supply you are using specifically? Thanks...

The exact type of power supply isn't all that important. What is important is that you have one that produces 5 or 6 volts DC with plenty of current.

I hope mine is good enough for the task. I haven't tested it with all four skulls running at once. I hope to have all 4 skulls put together and ready to test next week.

My power supply is giving me 5 VDC at 5 amps. It also has two additional outputs which can provide 0 - 30 VDC at up to 1 amp each. I use the 5 AMP output for all the servos, and the other two outputs power the SSC-32 board and the Kit 74 board. (Earlier I said the extra two outputs were 0-12 VDC. That was a mistake. They are 0-30 VDC and each output is only 1 AMP. I was writing from memory and hadn't looked at the actual unit first.)

Here is a picture of what I am using:



I found this on ebay while searching for DC power supply. It was a good price, so I bought it. Not very compact, but that isn't a problem in my situation.

I will report back to let you know if a 5 AMP output is good enough to run 18 servos as soon as I get to test it out next week.

Does anyone know off hand if I have made a mistake, or will the 5 AMP 5 VDC output be enough?

I hope not, 'cause that's what I plan on doing! Well, two 5v 3A power supplies. Do you need to do anything special to keep your servo controller cool? I was thinking of putting in a muffin fan.