Axworthy Ghost Speed

**Doc Doom** · 08-13-2010,09:09 PM

I've done quite a bit of online research on the best way to build my Axworthy. I thought I had a plan using a wiper motor, but it works out to a maximum speed of 1.2 mph at the higher speed setting for a 12V power supply. By comparison, average human walking speed is about 3.5 mph. Does anybody know what speed is typical/best for an Axworthy?

**compoast** · 08-19-2010,07:27 PM

I noticed no one responded to your post so I thought I'd jump in.

I don't know if there is a typical speed for an axworthy. Some like it slow, others faster or fast. It really depends on several things.

First, what is the effect you are going for? I've never seen a real ghost but I would imagine one floating very slowly. It depends on your setup and the look you want.

The weight of the ghost is also a factor. A light ghost is sometimes less likely to derail at a higher speed and a heavy ghost may not look good flying too fast.

Personally, I find the axworthy a challenge and so try to make it as easy as possible. For me that means a light ghost, traveling fast with lots of pulleys making it zig-zag around. More pulleys means shorter runs and less sag between pulleys.

My advice, if this is your first axworthy, is just try it. Perhaps a simple setup with only 2 wheels or pulleys not too far apart and see how your motor does. Get the feel for it and expand.

Andy

**thisain'tmayberry** · 08-20-2010,09:56 PM

You can regulate the speed of any DC motor - such as a wiper motor with this DC motor speed controller - http://store.qkits.com/moreinfo.cfm/MX033 You wire it in-line between your motor and power supply. It allows you to change the speed of the motor without losing the torque of the motor. Cheap and works great. I like my Axworthy slow and I use a big ghost prop. This controller lets my wiper motor drive it all over the yard at a slow "float."

**Runfromron** · 08-21-2010,07:42 AM

Drive pulley size also dictates how fast the ghost goes. Do a little math, based upon the r.p.m. of your wiper motor, and you can easily fing out what diameter pulley you need to achieve the desired ghost speed. I would say keep the motor at its optimum (strongest) speed, and vary the pulley size to accomodate that.

JMHO

Ron

**Doc Doom** · 08-31-2010,09:37 AM

Originally Posted by Runfromron

Drive pulley size also dictates how fast the ghost goes. Do a little math, based upon the r.p.m. of your wiper motor, and you can easily fing out what diameter pulley you need to achieve the desired ghost speed. I would say keep the motor at its optimum (strongest) speed, and vary the pulley size to accomodate that. JMHO
Ron

If my math is correct, I'll need a 21" pulley on a wiper moter at top speed of 53 RPM to achieve a "flying speed of 3.3 MPH, average walking speed.

Anybody ever attached a wheel this big directly to a wiper motor?

**DaveintheGrave** · 08-31-2010,09:51 AM

I know some people use bicycle rims for pulleys. They would be about that size.

**Doc Doom** · 09-05-2010,11:22 PM

I thought I had a sweet, easy idea for an Axworthy Ghost. I made a a large (7" dia.) pulley from a set of tin plates and mounted it to the bottom of a ceiling fan. Ceiling fans are made to run for long periods of time and are silent. After a couple of months playing around trying to slow down the speed using various fan motor controls without success, I hooked it up to see just how fast it would be. As I feared, it was way, way too fast and looked unnatural, but not in a good way.

I went to my local Lowes and HD and spent some more time in the ceiling fan sections. Not all fans run at the same speed, but none of them indicate RPMs on the box, deferring to cubic feet of air moved. Fans with large, palm frond shaped blades appear to turn slower, but I can't afford $150 to see just how much slower. Ah well, my wiper motor is on the way....

**sikntwizted** · 09-06-2010,01:54 AM

Originally Posted by Doc Doom

I thought I had a sweet, easy idea for an Axworthy Ghost. I made a a large (7" dia.) pulley from a set of tin plates and mounted it to the bottom of a ceiling fan. Ceiling fans are made to run for long periods of time and are silent. After a couple of months playing around trying to slow down the speed using various fan motor controls without success, I hooked it up to see just how fast it would be. As I feared, it was way, way too fast and looked unnatural, but not in a good way.

I went to my local Lowes and HD and spent some more time in the ceiling fan sections. Not all fans run at the same speed, but none of them indicate RPMs on the box, deferring to cubic feet of air moved. Fans with large, palm frond shaped blades appear to turn slower, but I can't afford $150 to see just how much slower. Ah well, my wiper motor is on the way....

You ever thought of running the current through a dimmer switch? That would drop your speed to whatever you want.