Need help on round nylon type material “not so slippery”’

Cadillac STS

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I’m working on an adjustable arm system to hold my vacuum end to keep it held where the spindle is on my mill during cutting a part, CNC mill. I can hold the vac where I want it but it would be better to set it where I want and have it stay. Also could help hold coolant lines as needed in place and not move.

I looked at some holding devices but all were not stout enough to hold the vac hose.

So I decided to go with making a larger version of a traditional ball and link system. Using 2 inch towing balls for a car. First one is a welded 2 inch painted ball on a 2 inch receiver bar fo the base. That will be able to be bolted to my mill table. Next is a double ball, one connected to the other for the middle link. Last is a 2 inch chrome steel ball with the 3/4 inch threaded end. Plan is I can make fixtures that can bolt on to the end of the arm and it will be powerful.

(When I am done I'll post some pictures)

For the connecting links I am using 7/8 X 2 X 8 inch aluminum bars. Held in the middle with a 6 inch 3/4 carriage bolt and nut. Then for the pads that squeeze the balls to hold (This is the question of the thread) I used 1 inch nylon round stock. I put a 2 inch ball router bit in the tail stock of my lathe and it cuts a nice 2 inch concave for the pads, other end of the pad is a 3/4 inch hub to go in the aluminum bar.

Problem with first model is it works but on the painted ball the nylon slips. It holds the steel chrome balls ok but the painted first ball slips. I need a material that will hold but not mar up the balls.

So I need a suggestion for a material that is not as slippery as nylon. Still machinable so I can cut it easily in my lathe and not wear the router ball bit too much. Would PVC rod work better? Polyethylene? Need to be able to buy a foot or so to make 8 pads from. 1 inch to 1.25 max diameter. Would a firm or stiff rubber product work and what would it be called?
 
Might it be possible to give the balls a light sand blast or bead blast finish? This would certainly allow the nylon to grab securely. The question for you would be whether you want to keep the existing finish(es) on the ball(s).

It's probably a bit late for me to offer you an alternative to the trailer hitch balls ... but there's a line of products called "RAM Mounts" that use rubberized 1" balls and double socket bars. I used to use one to mount a GPS unit on my boat. It held VERY securely. They make a full line of products designed to hold electronics, fishing rods, cameras, etc. on motorcycles, boats, cars etc. Many of the mounts are easily adaptable for machine shop use.

https://www.rammount.com

https://www.amazon.com/l/2599345011
 
If you don't have a tool changer, this works pretty well. I built this for cutting MDF, pretty much eliminates the dust.

1540797313913.png
 
Could do that but it would mar up the balls. Then comes rust..

(About not using pads and just the holes noted above. Or roughing up the steel trailer hitch balls.)
 
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Might it be possible to give the balls a light sand blast or bead blast finish? This would certainly allow the nylon to grab securely. The question for you would be whether you want to keep the existing finish(es) on the ball(s).

It's probably a bit late for me to offer you an alternative to the trailer hitch balls ... but there's a line of products called "RAM Mounts" that use rubberized 1" balls and double socket bars. I used to use one to mount a GPS unit on my boat. It held VERY securely. They make a full line of products designed to hold electronics, fishing rods, cameras, etc. on motorcycles, boats, cars etc. Many of the mounts are easily adaptable for machine shop use.

https://www.rammount.com

https://www.amazon.com/l/2599345011


Very nice, and they sell individual components too with low prices. If I pack it in I'll go with this product but I'm pretty far into the project already. But you got the idea right on.
 
You must have one BIG vac system...the size of balls and arms that you propose could hold a car! Here is what I use on my manual mill, it's just an old work light mount.
vacmt.jpg
vacmt2.jpg
 
Solved the problem by increasing the size of the nylon pads to 1.75 inches. More surface area more grip.

But..

My setup was way too large for what I needed. I ended up ordering some Ram Mount components that worked perfectly. I bought one one inch rubberized ball on 3/8 16 bolt, milled a custom T nut to hold that to the table. Two two inch links they are nice powder coated aluminum. Two double rubberized ball links. And then the medium claw mount with one inch ball. The claw is usually for mounting on a post but I used it to hold the vacuum hose. Nice high strength setup, looks good and is easy to adjust

Thanks to the forum for ideas.. my setup too large, the Ram Mount idea..
 
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