Friday, September 26, 2014

Cauldron Creep 3.0 - Frame and Neck Motor Diagrams

One of the biggest improvements over the Cauldron Creep 1.0 was the new neck mechanism I created in Cauldron Creep 2.0. The new design is easy to build, fast to assemble and doesn't requires a giant hump to hide. I know, I KNOW...the hump is part of the charm, but I like medium sized humps.

The Frame

The frame is based of measurements from a Bucky 4th quality skeleton. Why is it important to mention it is 4th quality? 4th quality means you will have warped bones, poorly installed hardware, and who knows what else and this make them all kinda of unique in a way the would infuriate an engineer. So use the measurements for the legs and arm as guidelines, maybe add and inch or two for good measure then cut down as you fit the bones to the frame. (fitting bones to the frames will be in another post).

It's hard to see the details here so make sure to download the Cauldron Creep 3.0 How-To PDF.
The How-to is being updated as new sections are added, such as how to wire the led eyes, make costume, attach bones, etc. The link to the latest PDF of the How-To can be found here.

So here is an overview of what a cauldron creep looks like naked:

Neck Motor Mechanism

These plans are based on my current cauldron creeps version 2.0 and 3.0. Since I first made the Cauldron Creep in 2008 a few things have changed.

Firstly, the once cheap and widely available 6rpm window crank motors have become rare and pricey (up to $50). There is a substitute motor listed in the how-to parts list. This is a small geared motor that runs off of AC current. I have heard you can find DC current version of it, and if you can I recommend it. DC is much friendlier to beginners and hobbyist because the voltage are rarely high enough to be dangerous.

Secondly, the mechanism now is more compact and requires less bar stock (which is pricey). It is also easier to make and assemble. It doesn't require as large a back hump to operate.

The wood block is used as a mounting base for the motor as the mounting points on the motor didn't allow it to be aligned the frame centerline if mounted to the PVC pipe. It also creates a stand off which helps get the motor more to the center. Depending on what motor you end up using and the fittings associated with it you be able to figure out your own stand off and alignment needs.

You'll also see I used a 4 inch KO Test plug as part of the mechanism. I used it thinking it would reduce snagging or pinching. I recommend using a 2.5" to 3" piece of bars tock with one hole drilled and tapped if possible where the motor connects. Make sure the rotation of the motor tightens the threads as it turns. If you can't reverse the motor you'll have to mount it on the opposite side so it that it tightens threads instead of loosening them as it turns.

Here is a preview of what you'll find in the PDF.

This is a schematic of the neck motor assembly:

And the exploded view:

And the side view or the neck mechanism:

And finally a close up of the neck mechanism details:

Wednesday, September 17, 2014

Cauldron Creep 3.0 - Cauldron Diagrams

It's been hectic for the last few months and it's only going to get worse so I am trying to squeeze this into one afternoon.

I took pictures and measurements the last few times I made a cauldron creep. My creeps have been based off of the dimensions of the "Bucky" anatomical skeleton. If you have a costco/walgreens posable skeleton you have to make adjustments for the length to arms legs and torso height.

What I have managed to assemble here is the diagrams I had made for the neck mechanism and cauldron motor.

I tried to make them clear but you know how sometime you either over think it or because you know the subject so well you skip over important things. If you have question I'll try to answer them.

Here is the parts list for the cauldron motor assembly:

10” to 12” section of 3/8 in. W x 1/2 in. H Aluminum C-Channel with 1/16 in. Thick

2” to 3” PCV end cap
2 1” x 1.5” x 3” length of oak, walnut, or other hardwood
2 1” x 1.5” x 2.5” length of oak, walnut, or other hardwood
12” to 18” diameter circle of wood, mdf, or particle board
Plumbers Tape 3/4 in. Galvanized Steel Hanger Strap Wiper Motor (or similar) DC Motor/ LED Light Dimmer (option 1)
ATX power supply from computer (option 2)
1 ¼” drywall or wood screws
3” drywall or wood screws

Here are the diagrams high-res and easier to read tehn screenshots on a blog:

You will also want to learn how to find the center of a circle here or here.

The motor assembly in the cauldron. It consist of a windshield wiper motor, using the low power inputs from a 5.5v power source ( I use an ATX power supply from an old PC). This drives a piece of 3/8" U channel aluminum with a 2" PVC end cap bolted to the end. This is a cup that the stirring rod rest inside of. The stick is not attached to the motor base. To ensured that the stick doesn't bind while turning the PVC cap is filled with hot glue or a round insert of cardboard is placed inside. Sharpening the end of the stirring stick to a dull point will allow it to turn fore freely as well.

To make modifying or servicing the motor assembly or cauldron easier I have created a sandwich style construction. The motor is attached to a round cut out that rest inside the cauldron. It screws or bolts through the cauldron itself into a base underneath which has an "H" shaped riser to clear the ground and allow a pipe for fog and electronics and lights underneath.

Here you can see in pink that sliding rail system i devised for adjusting the creep in relation to the cauldron. It seems in practice you might want to make it longer and cut down to size instead of coming up short.

Again I'm short on time for blogging but I can answer questions so leave them in the comments.
I'll be working on the neck mechanism and update as soon as I can.