Mechanical: Help with cauldron creep head movement
Hello there, is this your first visit?
Register
Page 1 of 2 12 LastLast
Results 1 to 10 of 14
  1. #1
    Join Date
    Sep 2018
    Location
    Boston suburb
    Posts
    23

    Default Help with cauldron creep head movement

    I could really use some advice to save me time and aggravation. See my video first: https://youtu.be/dUAD_fsq1fA

    I'm having a couple challenges with the head. First, what should I do to get the head to come up more vertical? At its highest point, it is still too angled down for my taste. My short metal piece is around 5.75" and longer one is 8".

    Second, the reason why the head is positioned directly on the spine (instead of on a 90 degree elbow) is because I'm trying to also introduce a side to side motion according to this idea: https://youtu.be/DtuUMaa2YPY

    Clearly that's not working, maybe the rod at the very end is not heavy enough, but I'll worry about this issue after I fix the first one.

    Thanks for any advice!!

  2. Remove Advertisements
    HalloweenForum.com
    Advertisements
     

  3. #2

    Default

    Really hard to say from here but I would do away with the double linkage and try a single bar from the motor arm to the pvc. You really need to start by positioning the head upright where you would like it to be at the highest point and then configure the linkage from there.

  4. #3

    Default

    The other thing that's killing the movement is the tee configuration. The pivot point is way above the pvc that you're moving, so the whole assembly is acting like a swing instead of a seesaw. You'd get much better movement if you use a 4-way fitting between the shoulders and get the linkage connection point much closer to that pivot point. Your motor arm is only giving you a set amount of movement in 180° so the closer the linkage attaches to the pivot point, the more movement you'll get. You may have to add counter weight to the other end for that deer motor to operate because the closer the linkage is to the pivot point, the more force it will require to raise the head.

  5. Remove Advertisements
    HalloweenForum.com
    Advertisements
     

  6. #4
    Join Date
    Sep 2008
    Location
    Sunny California
    Posts
    2,815

    Default

    Like J-Man said, first thing is turn that T up and go from there.

  7. #5
    Join Date
    Sep 2008
    Location
    Gotham City
    Posts
    2,449

    Default

    I've seen a version with a lower pivot point like yours. I don't think it's an issue if you fix your shorter metal connector to the motor. If you don't allow it to swing around the screw so loosely and fix it tight, you will have greater swing, more than 10".

    "Do I really look like a guy with a plan? You know what I am? I'm a dog chasing cars. I wouldn't know what to do with one if I caught it. You know, I just do things."

  8. #6

    Default

    Help with cauldron creep head movement
    Here's a diagram showing the difference in pivot point location. The first example has the pivot point above the arm being moved, similar to bluesjumper's configuration. The second example has the pivot point in line with the arm being moved. The blue lines represent the distance the linkage has to move to get 90 degrees. Using the same linkage attachment point in both examples you can see that it takes nearly twice the amount of linkage movement to get 90 degrees with the arm below the pivot point. These drawings are not to the dimensions of bluesjumper's setup but you get the idea.
    linkage example.jpg

  9. #7
    Join Date
    Sep 2018
    Location
    Boston suburb
    Posts
    23

    Default

    J-Man, you are my hero! I applied your initial ideas and it didn't take much experimenting to get the motion I wanted. And the lateral head movement started to work as well. Here is how it looks now: https://youtu.be/tlpGGj5-MXQ

    Thanks again!!

  10. #8

    Default

    Awesome! Looks great!

  11. Default

    Looks much better now. I used the same method with mine. One thing I did differently is I put a piece of wood dowel in the horizontal bar to add weight so it stayed in contact with the main structure. It allows a smoother operation of the turning of the head.

  12. #10

    Default

    I have a question for you guys that use this type of head movement rig. Why are they almost always made so that the head turns when it goes down and straightens when it's up? If I were stirring a cauldron and leaned over to look into it I wouldn't turn my head away. Just seems to me (being picky) that the animation would look better reversed with the head looking down into the cauldron when it's down then turn to look at visitors when it's up. Just an observation and again, just me being picky and particular. (Touch of OCD perhaps) I didn't animate mine this way so I'm not 100% versed in this method of doing it. Mine just goes up and down and uses gravity to drop the jaw open when it's up.

  13. Remove Advertisements
    HalloweenForum.com
    Advertisements
     

 

 
Page 1 of 2 12 LastLast

Similar Threads

  1. Lighting: Cauldron and coals for Cauldron Creep
    By kimcfadd in forum Halloween Props
    Replies: 6
    Last Post: 09-17-2016, 07:42 PM
  2. Cauldron creep head turner
    By Dogbite in forum Tutorials and Step-By-Step
    Replies: 16
    Last Post: 09-06-2014, 04:32 PM
  3. Mechanical: Cauldron Creep in process, he's a real head turner
    By Dogbite in forum Halloween Props
    Replies: 5
    Last Post: 10-31-2013, 08:24 AM
  4. Mechanical: Need help desperately with my cauldron creep head movement
    By aggiesheltervet in forum Halloween Props
    Replies: 11
    Last Post: 10-11-2012, 08:24 PM
  5. Mechanical: Need help with smoothing movement - Grinder Creep
    By devils chariot in forum Halloween Props
    Replies: 25
    Last Post: 05-18-2011, 02:50 PM

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •