remove stuck RB67 tripod bushing

[BetterSense]

My RB looks like it has a 1/4 inch bushing in it. I want to take it out so I can use a 3/8 thread but the slot is stripped. Do I have to drill it out?

 

[largely]

If you (or someone you know) has a Dremel tool just use one of the small abrasive discs to grind a slot for a screwdriver. If you do this be sure to protect the camera from grinding dust.
Or go to anyplace that sells tools and acquire a tool called (generically) ann EZ Out or screw extractor. They're not too costly. Just tap it in gently and use a wrench or pliers to back out the bushing.
If its stuck really tight it may need to be drilled out. If you're not experienced at this I'd seek out a machine shop. It would be very easy to cause significant damage by trying to do this by hand. A shop shouldn't cost too much.
Good luck at whatever approach you take.

Larry

 

[mgb74]

+1 on the screw extractor. Should be available at any decent hardware store. Also Sears.

Alternatively, use a 1/4" left handed bit. It should have enough "bite" on the 1/4" threads. Unless the insert is rusted in place, it should turn out with the bit.

 

[shutterfinger]

The taper on an Easy Out will most likely cause the easy out to bottom against the base of the tripod socket before it grips the insert threads.
This power extractor, http://www.sears.com/craftsman-drill-extractor/p-00952152000P?prdNo=4&blockNo=4&blockType=G4 , will possibly work better.
Another trick is to screw a bolt with a nut on it into the socket, tighten the nut against the insert, then unscrew the bolt.

The tripod socket plate should separate from the camera body after removing the 4 screws at the outside corners of the plate making working on the socket easier.

 

[Tom1956]

The taper on an Easy Out will most likely cause the easy out to bottom against the base of the tripod socket before it grips the insert threads.
This power extractor, http://www.sears.com/craftsman-drill-extractor/p-00952152000P?prdNo=4&blockNo=4&blockType=G4 , will possibly work better.
Another trick is to screw a bolt with a nut on it into the socket, tighten the nut against the insert, then unscrew the bolt.

The tripod socket plate should separate from the camera body after removing the 4 screws at the outside corners of the plate making working on the socket easier.

Agreed on the Easy Out idea--bad idea. I too, was wondering about those 4 screws on the base plate. And also agree on the nut-and-bolt idea, even if you have to die-grind the nut to a taper so it won't lock against the base plate. I bet I could get that sucker out without tearing things up.

 

[mgb74]

There are a few different styles of screw extractors. Some have a sharper taper than others and should "bite" before bottoming out. But certainly best to confirm that it won't (bottom out).

 

[Trail Images]

If the internal threads are good on the bushing I would try the idea of taking a 1/4" bolt with a nut threaded onto it and screw the bolt into the tripod bushing. Be sure to get as much thread into the bushing as possible without bottoming out. Then turn the nut down the 1/4" bolt until it makes contact with the bushing and tighten firmly but without too much stress. Then try turning the bolt back out and hopefully the bushing will release and back out too.

 

[illumiquest]

I'd get a flat head and tap a small nick into one side of the bushing and then knock it gently until it starts to spin. It's brass on brass so I doubt it's that stuck. You could also pull those four screws and the plate will come off if you don't want to whack on it while it's attached to the camera.

 

[MattKing]

Mine sometimes comes loose on its own when I take the camera off of the Mamiya left hand grip.

That and the stripped slot makes me wonder whether some "_____" has put Loctite or something similar on the adapter bushing.

 

[Tom1956]

If the plate comes off by the 4 screws, I'd take it off and drop the whole shebang in some acetone for a day. Then I'd heat up the plate over a candle and the insert will likely twist out with a feather.

 

[Xmas]

Change tripod

 

[lxdude]

There are a few different styles of screw extractors. Some have a sharper taper than others and should "bite" before bottoming out. But certainly best to confirm that it won't (bottom out).

There is a type that is square and tapered that will work. Instead of being screwed in, they are driven in and turned. Gentle tapping with a hammer will get enough bite on the brass insert. Also, it might be as easy as putting the end of screwdriver blade against the side of the slot and tapping its handle with a hammer.

 

[lxdude]

Mine sometimes comes loose on its own when I take the camera off of the Mamiya left hand grip.

That and the stripped slot makes me wonder whether some "_____" has put Loctite or something similar on the adapter bushing.

You could be right. I don't recall ever having one jam that tight.

 

[illumiquest]

I also had a stuck insert once, a gentle tap with a hammer took care of it...

 

[gone]

First, spray some penetrating oil on it and let it sit over night after giving the insert a few taps w/ a small hammer or side of a wrench. Not that hard. Then thread in an appropriate bolt w/ a nut on it. Once the bolt is threaded into the insert, tighten the nut down to jam it, and back everything out.

Or, if you don't have a bolt and nut, after it's soaked overnight w/ the penetrating oil take a chisel and cut two notches into the stripped part, take a screwdriver and give it a couple of light taps w/ a hammer to drive it into your homemade slot, and back it out.

 

[AgX]

Why not just use another adapter to fix the camera on a 3/8" tripod head/tripod plate?

 

[BetterSense]

I tried a 1/4 bolt epoxied in. It just broke the epoxy. Tried a chisel at an angle and it just broke a chunk off. Ended up drilling it out with a hand drill and then ruined a very nice 3/8 tap by dremeling the tip off to clean out the threads.

Got my bogen QR plate mounted, and found out the QR plate is undersize and doesn't fit my tripod. Sigh.

 

[Tom1956]

Back to the drawing board. Don't fret. You don't want to hear my story of the time I used and ordinary pulley-puller on the vibration damper of a Chevy engine back in '84, and the bag of worms I cause myself. There's been dozens of these disasters since.

 

[BetterSense]

Well, removing the bushing wasn't a total loss. Now that I need to buy a new QR plate anyway, it just wasn't necessary. I can't figure out how this QR plate doesn't fit. It must be an off-brand knockoff of a real Manfrotto plate.

 

[shutterfinger]

Need to clean burred threads on a nut or insert? Take a bolt or screw of the same thread and clamp in vise grips or a vise. Next take a taper (triangular) file and cut a grove into the threads holding the file at a 30° to 45° angle to the shaft of the bolt or screw. Once the lead edge of the grove is into the screw/bolt body cut a second and third grove 120° and 240° (thirds of the screw/bolt diameter).
Now place the V of the file in the thread at the rear most edge of the grove and file across the grove until the burr from cutting the grove is gone then move to the adjoining thread and repeat until reaching the tip of the screw/bolt. Be sure to follow the thread. Repeat for the other groves.

Carefully start your thread chaser into the damaged thread, turn 1/4 to 1/2 turn, back off 1/8 turn then turn forward repeating the pattern until you bottom or have unmodified threads through the nut.

A 4 inch to 6 inch taper file works best for this machinist trick.

 

[lxdude]

ruined a very nice 3/8 tap by dremeling the tip off to clean out the threads.

No, you didn't ruin it. It's called a bottoming tap. I made lots of them out of regular taps back when I was a machinist. They are a necessity in a machine shop for getting sufficient threads in shallow blind holes. First you go as far as you can with a regular tap, then follow with the bottoming tap. Even now, I occasionally have had to make one while repairing something. Once you make it you've always got it.

For future reference, when cleaning up threads in fairly soft material like brass or aluminum, you can make a clean out "tap" by using a steel bolt or screw, cutting or grinding one or more grooves into the thread like the flutes in a tap, and running it through the threads. I like doing that because it doesn't change the dimension of the thread, as it doesn't remove any of the thread itself, just debris, and it straightens out any damaged thread without cutting it away. It works with mild steel too, but in that case it's best to use a hard grade of steel bolt or screw.

EDIT: Shutterfinger just described a good method in comprehensive detail.

 

[Tom1956]

lxdude. I was never a machinist; I'm a printer. A printer is a under-equipped machinist. And that's just about all there is in difference between the 2 fields. Or to put it in other terms, a machinist is a printer; lucky enough or smart enough to not have any printing equipment in the shop.