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chevynut
12-30-2014, 03:00 PM
Hi guys, I know someone knows this but what is the approximate balance point distance for the rotisserie pivot for a tri5 body? Assume the mounts are at the cowl and under the tailpan, as is usually the case. I need the distance from the two body mount locations to the CG. Thanks!

chevynut
12-30-2014, 03:58 PM
Did some searching and found that it's somewhere around 14".

MP&C
12-30-2014, 06:43 PM
You may find that's for sedans.. I used 11-1/2 on the wagon, perfectly balanced. But then a Nomad may be different still

Rick_L
12-30-2014, 07:30 PM
Front or back? Those body mounts are at a different height on the body.

MP&C
12-30-2014, 07:52 PM
Dang, more measuring to do.....

chevynut
12-30-2014, 08:43 PM
Yes I realized it would be different front and rear after doing a little research and thinking about it. If a wagon is at 11.5" up from the cowl body mount, I would think a sedan would be lower (closer to the pivot) since the roof is lighter. But I saw where Acardon said his HT balanced at 14". I wonder if the measurements were on different ends of the car.

I think I have what I need. I'm working on modifying my fixed position rotisserie with 3 ton hydraulic jacks so I can get it as low to the ground as possible, and still be able to raise it high enough to rotate it 360 degrees. If I don't do that I'd have to raise the body up to the arms which would be about 4 feet off the ground. I'd rather not raise it that high.

chevynut
12-30-2014, 08:55 PM
Front or back? Those body mounts are at a different height on the body.

Turns out they're only different by about 1/2". The cowl mount is slightly higher on the frame.

Rick_L
12-31-2014, 04:52 PM
Wow, I knew mine was top heavy but I didn't know how bad. Mine only has a 3" drop. Even with the high cg it's not that hard to rotate.

And I started this front/back question but mine is currently set at the same height front and rear.

My rocker panel is 23-1/2" off the floor with the body horizontal. I can sit in the door opening normally.

My rotisserie has a longitudinal member. I can rotate the body to where the bottom of the rocker touches that member. About 87 degrees.

The reason I have it set up this way is so that the top clears the 8' ceiling in my shop, and for a reasonable working height.

chevynut
01-01-2015, 08:44 AM
Do you guys know the bare minimum height above the center leg the pivot point has to be? I read that Acardon's was about 41" and he had about 1" clearance for his hardtop. I'm not sure how the CG adjustment affects that but it should to some extent. My rotisserie has some bolts sticking out of the top of it that I'll have to clear, or move them to the side f the center leg. I don't know why they did that, but with a fixed rotisserie it probably wasn't an issue. I need to make the body clear, but I also want to drop it as close to the floor as I can. I may just go ahead and make the jack bracket adjustable a couple of inches.

NickP
01-01-2015, 08:56 AM
Rather than push it up, why not pull it up?

Adapt a different cylinder that pulls. Might take some design work but if it is lower while at rest, then transporting it may be eaiser.
http://shop.lkgoodwin.com/media/images/products/zinko/zpr056-zpr106/medium.jpg

MP&C
01-01-2015, 06:50 PM
More measuring...

http://i5.photobucket.com/albums/y167/rmccartney/Misc/Picture1806.jpg


5-1/2" height on the standoffs...


http://i5.photobucket.com/albums/y167/rmccartney/Misc/Picture1807.jpg


About 17 to the center of the pivot, minus the 5-1/2, for a pivot to body offset of 11-1/2.


http://i5.photobucket.com/albums/y167/rmccartney/Misc/Picture1808.jpg


From crossbar to pivot... 42"


http://i5.photobucket.com/albums/y167/rmccartney/Misc/Picture1809.jpg


http://i5.photobucket.com/albums/y167/rmccartney/Misc/Picture1810.jpg


Given body width of 74" (correct me if I'm wrong there...) add 37" above pivot for overall height of 7' 2-1/4", so well under the 8' height of short garages..


http://i5.photobucket.com/albums/y167/rmccartney/Misc/Picture1811.jpg


http://i5.photobucket.com/albums/y167/rmccartney/Misc/Picture1812.jpg


Height of the pivot from the floor...


http://i5.photobucket.com/albums/y167/rmccartney/Misc/Picture1813.jpg


http://i5.photobucket.com/albums/y167/rmccartney/Misc/Picture1814.jpg


And here's a shot of the height and CG adjustments...


http://i5.photobucket.com/albums/y167/rmccartney/Misc/Picture1815.jpg

chevynut
01-01-2015, 08:23 PM
Thanks for all the measurements Robert. I decided to make mine 42" from the top of the leg to the pivot as well, with the jacks all the way up. Do you know how much room that leaves between the leg and the roof and rocker when the car is rotated? With my jacks all the way down, it's 22" from top of the leg to the pivot. Then with the arms 14" or so below that, the top of the arms should be 18" off the floor. I like your posts on the ends of your arms...I think I can do something similar.

Man your rotisserie looks like it's built for a tank compared to mine. All my tubing is 1/8" wall on the legs and main upright. I put 3/16" wall tubing over that for the height adjuster that the jack attaches to. I don't know the thickness of the arms but I'll take a look at them. Mine has an acme screw that you adjust to get the body at the CG.

MP&C
01-01-2015, 08:37 PM
All of the square tubing is .22 wall thickness, so yeah, pretty stout. This is about all I have showing distance from car to lower bar.. I don't recall it being too close though.


http://i5.photobucket.com/albums/y167/rmccartney/Rotisserie%20Fabrication/Picture071.jpg

chevynut
01-01-2015, 08:59 PM
Thanks for the feedback. I like your "safety pins" too. I have always been freaked out about forgetting to tighten some of the locking bolts and rotating the body, and having it slide off and damage it. I plan to put some kind of stops on mine.

MP&C
01-01-2015, 09:12 PM
If you look at the top picture, the body arms have 3/4-10 bolts for "set screws" I added the 3/4 diameter hitch pins in case they let loose.. :D