Cheap DIY industrial-strength shaft collars for know-your-limits racks that use EMT

[stovepipe]

I bought the KYL rimfire/airgun target rack from ShootingTargets7 recently -- I love 'em. Before I even had them put together, I started looking for some off-the-shelf steel shaft collars that would fit the 3/4 EMT. I figured steel would look cool and hold better too. BUT, the outside diameter of 3/4 EMT is an odd size for which no properly-fitting steel shaft collars could be found. Then I started looking at what kinds of things electricians use for EMT connections, collars, etc. What I found that was ALMOST perfect was compression couplers. All they needed was a little DIY hack job and they work GREAT. They hold REALLY tight and can be loosened and repositioned and re-tightened -- no problem. If you like the Mad Max look, then they look cool too.

I didn't buy my EMT compression collars -- they were spares that my friend had laying around. But here is an example of what Lowe's has in my area that are the same thing.

I used a hack saw to cut the threaded part off of one end. Then I used a small grinder bit in a hand held drill to remove the internal shoulder so that the EMT could go all the way through it. Done! Well, one done. You gotta make two of 'em.

And this is what it looks like on the target rack.

stovepipe

 

[Ta-Ta Toothie]

The plastic clamps they give you are pretty lousy and break very easily. I had replaced mine with SS collars.

 

[ShootingTargets7]

Hey William,

This worked, thanks for sharing.

Years ago I had bought those and thought about using them.

I'm glad they are working for you but having to cut thousands
of them in half is just not practical for us in scale.

Sorry I had not responded to you earlier, I am so busy these days
I can't keep up.

Mark

 

[Ta-Ta Toothie]

A, 1" ID collar with a set screw can be bought cheap enough.

 

[stovepipe]

Hey William,

This worked, thanks for sharing.

Years ago I had bought those and thought about using them.

I'm glad they are working for you but having to cut thousands
of them in half is just not practical for us in scale.

Sorry I had not responded to you earlier, I am so busy these days
I can't keep up.

Mark

No problem Mark. This is hacker stuff. Even though they are cheap (5 of 'em for $6), there is still the labor. I have a feeling that a year from now I'll still be the only guy on the planet with shaft collars made from compression couplers. Fun stuff.

stovepipe

 

[stovepipe]

I just now received a pair of the new Hard Urethane 3/4 EMT shaft collars from shootingtargets7 -- literally just now opened the package. They are clearly not brittle like the previous PolyCarbonate collars I had. I haven't clamped the Hard Urethane collars onto my target yet, but I'll do that later today just out of curiosity. I will, however, be using my DIY collars forever -- can't beat 'em when it comes to holding power.

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[rob_g]

On my kyl targets I put a steel washer on either side of the paddle and a piece of poly hose between the washers. The poly hose fits tight enough on my EMT cross bar and keeps the paddles/washers in place while the steel washers on either side let the paddles swing freely. The poly hose can take a hit without being too damaged

 

[stovepipe]

I just now did a quick test of the new Hard Urethane 3/4 EMT shaft collars from shootingtargets7. Since I'm going to use my DIY collars on my KYL rack forever and don't really need the Urethane collars, I figured my test would be mostly to see if the Urethane collars had the same problem as the older PolyCarbonate collars that were too brittle. So I intentionally tried to break 'em by stretching them and over-tightening them. I took the machine screw off of the collar and pulled the "tabs" far apart as if I was trying to wrap the collar around a very large diameter pipe. I had the "tabs" pulled apart about two inches and the collar didn't mind flexing like that at all. Then I put the collar on to one of the legs of my KYL rack (it's the same 3/4 EMT as the cross bar) and tightened the allen screw until the tabs were making contact. I put my weight on the collar trying to make it slip down to the ground and tried to make it twist around the leg also. I couldn't make it move. I didn't try hitting it with a hammer or anything like that because I didn't want to bash up the legs of my KYL rack. For the final test I tightened the allen screw several full turns past the point of the tabs already being flush with each other. I warped the tabs to where they looked like two curved tabs that were only touching in the middle. The collar was still tight and did not crack. Then I took the collar off the leg and set it on a table next to the other Urethane collar that had not been abused (still new). I went in the house for about five minutes and when I went back to the table on the porch I could not tell which of the two Urethane collars was the one I abused. The warped tabs had gone back to being flat. That was interesting!

That was the extent of my test. I didn't put the collars on the cross bar and shoot at the target paddles and I didn't shoot the collar. It's obvious to me that the new Hard Urethane 3/4 EMT shaft collars from shootingtargets7 are not going to crack like the older PolyCarbonate collars did.

stovepipe