Instruction: Given a question and the related document, and generate the answer to the question based on the information provided in the document.

Input:
Question: How does one invert the center column? I've tried channel locks, lid grips, everything. Seems impossible to screw off.
Document: The caveat is that it's so wobbly on the actual screw shaft that tensions the center column that I'm not super optimistic that it won't eventually round the corners and strip out, and I've already found that you need to really tighten it down to keep the column from rotating. It smells a little - no big deal. I like the design for the feet and the legs operate fine out of the box without adjustment. It seems quite sturdy. On to the head. Three bubble levels - yep three.
Backed the set screw out a few turns to flush, mated the two plates and was in business. Later I returned to these three set screws and used them the proper way. Do not tighten the pistol grip base all the way to the center column base, rather, leave about a 1/32nd (1/2mm) gap between the two plates, then dial the set screws up to lock everything stable. This prevents your plates from becoming seized together.
OK for many consumers this can be startling and if you are not use to checking your products for loose screws you may not even be aware of how many items you own with this problem. I found two loose screws in the leg tensioners. I found one OVER tightened screw in the base the pistol head mounts to on the center column.
From the feel of things, it's a heavy duty pistol grip head.One issue that really pestered me until I found a video online... The center post slides up and down, as it should. There's a tension screw on the side of the tripod which presumably locks the center post in place. This screw was so dry, it was incredible difficult to turn by hand, even with the plastic turn key. I finally got it off, and the threads definitely looked stripped.
This is a great tripod. Very solid and durable. Good heavy-duty metal construction. I love the pistol-grip ball head which lets you position your camera where you want quickly and easily. The quick-release camera mounting plate is great. I really like the way the center column slides up and down quickly to where you want it, and locks in with a twist of a lever.So why don't I give it 5 stars?:1. No instruction manual whatsoever.2.
but also with three different angles (see the photo I uploaded)- The center column has a standard camera screw at the bottom, allowing to position the camera (or the ball head) below for close-to-the-ground shoots (see photo).- The ball head can be locked in place using three screws under the column top plate - more on these later on (see photo).- The ball head itself is probably worth close to the price of the whole thing.
You don't get the feeling anything is going to break on this puppy.Things to watch out for1) Tighten all screws, another reviewer mentioned this and I had the same problem. Some of the screws were altogether too loose2) Lubricate screw that tightens center post. Mine was dry as a bone, although once I put a little oil it was as smooth as could be. The handle that tightens this screw seems a tad loose. Almost like there is a spring in it.
The Ravelli APGL4 tripod is built like a tank. It is solid and feels indestructible. The head works very well to adjust to any position. I honestly think this tripod could last for many,many years. The pistol grip is awesome and rock solid.The bad news is the smell. The quick release plates that connect the camera to the tripod just smell horrible. I've tried everything to get rid of the smell with no success. They stink up an entire room.
The legs are very rigid,and everything is metal, except for the rubber feet and the plasticballs on which they pivot. I really like the adjustable-tension leg locks.Instead of tossing the tripod when your leg locks loosen from wear,a quick tweak of the screw is all that's needed to restore performanceto like new. The metal leg-lock levers seem pretty heavy duty, andlook like they will stand up to many years of use.With the camera mounted, this thing is rock-solid.
Only thing I would say is TIGHTEN THE SCREWS before you do anything, I almost lost one when it went fly out of the leg. Also tighten the head on to the column, some times when you turn the grip it will unscrew the head. If you tighten the head down to the base of the column by grabing the center column and rotating the head you should be good to go.
Answer: Start by raising the center column about half way. Then using the smaller allen wrench included with the tripod, loosen the three screws on the under side of the head. These are rather easy to find with the column raised. once they are loosened, simply unscrew the ball head assembly from the top of the column and then screw it onto the threaded screw at the bottom of the column. When you have finished your photography unscrew the ball head assembly from the botton and re-install on the top. Remember to tighten the small screws under the mounting flange to secure the ball head again to the top of the tripod. The mounting flange on top is not meant to be removed and continued attempts to do so using tools you described, may damage it and diminish its functionality.