Introduction: Ken's Camera Boom

My goal was to build a camera boom for may Super 8 film project. I looked at what others have done in order to get a a good idea of how they worked. I build a model out of 1/4" dowel just so I could see the mechanics that keep a camera in one position throughout its range of motion.

I started building this project without the idea of making it an Instructable so I guess I'll try to reverse engineer my boom construction and present it to you guys as my first Instructable.

Parts List:
Stuff I bought-
1 8" x 5' cardboard form from Home Depot (building supplies)
2 1-1/8" x 10' conduit pipe from Home Depot
1 3" x 3' ABS section from Home Depot- they have a rack of them in the plumbing dept.
4 1" x 2" PVC pipe connectors from Home Depot
1 1-1/4"x1-1/4 aluminum angle from Home Depot
2 5/16" x 3' threaded rod from Home Depot
1 5/16" turnbuckle
1 2part epoxy kit
Assorted nuts-bolts-washers-fittings
1 used camera pan head won on eBay ($10.50 + ship)

Total cost: $55 approx

Stuff I had on the shelf-

8 inline skate bearings (from my skate box)
1 large iron plate from patio umbrella stand
1 Celestron telescope base (I can reuse as telescope base if I choose)
1 piece 8"x8" x1-1/4 clear pine

Tools Required-
Band saw
Drill press
Drill motor
Hack saw
Picture frame saw
Assorted hand tools- File, drill bits, wrenches, etc.

Step 1: Base Column Construction

Base construction-
As the amount of weight that a camera boom supports is not huge, maybe 30-40 lbs. max, I was looking for a way to mount the boom without using a tripod as I only have two and they are slated for other uses for my film project.
I started by guesstimating how high the base should be. This is determined by the max height of the boom would need to rise. As this is a garage project, it turned out to be 36". So, I cut 24" off the cardboard concrete form by carefully using my picture frame saw. It has a special saw edge that was gentle on the cardboard form.
Next, I needed a platform to mount the boom system. The easiest way was to cut a circle that matched the ID of the cardboard form, about 7-3/4". I inserted this at one end and epoxied it. The epoxy would probably be strong enough but I added 4 dry wall screws with flat washers anyway.
I also drilled a 5/16" hole in the center to receive the 5/16" threaded rod.

Item next was to create an access hole so I could get my hand inside to assemble the steel plate base. I cut 2 holes about 6" from the top with a 2-1/2" hole drill. Cleaned it up a bit with a shop knife. I can get my hand inside to assemble the parts that hold base together.
And, while I had the big 2-1/2" hole drill set up I drilled a single hole in the opposite side to make it easier to drag this beast from place to place.
So, what we have now is a 3 foot high cardboard form with a wood top epoxied and screwed in place with some screws for extra strength. On to next step...

Step 2: Steel Plate As Weighted Base

I just happened to have this 1/2" X 2' plate of steel that is a patio umbrella stand base. It has a hole in the center so I didn't have to drill it. And, it already had some feet on it so the nut on the bottom wouldn't be a problem.

Here's how I assembled-
All that has to be done is to tie the base column to the steel plate with a 5/16" threaded rod to the wooden top and tighten it down with a turnbuckle. At the wooden top end I used a 5/16" screw-eye with a piece of the "eye" cut out so I could connect to one end of the turnbuckle. I also had to countersink the the nut and washer so the boom mount would fit.
Once all hooked up I centered the column on the steel base and tightened the turnbuckle a couple of turns.
BTW: the compression strength of these cardboard forms it pretty good. I didn't stand on it or anything drastic, but I'm pretty sure it could hold at least 100 lbs.

One last step on the base-
My boom mount is the base of my old Celestron 4" telescope. I know, pretty drastic decision to modify an expensive toy.
I has several 1/4" tapped holes in the bottom. I just matched up 2 so I could run bolts from the bottom of the wooden top.

Step 3: Layout Support Tube

If I had to do this project over I would build a tool to create the bearing mounts and aperture for the boom rods to reside.
The problem is laying out needed drill points on a ABS tube. The easiest tool would be just a box of 4 sides (no ends) that is exactly the OD of the piece of 3" ABS that will support the booms. That way you you can find the exact center drill points. I was stupid or lazy on this and I was off by some wiffy-jiffies.

Layout two holes to receive the bearings, and two holes 90 degrees for the booms. You want the holes for the booms to be large enough so you can tilt the boom up and down.

I choose 5-1/4" centers for the bearing holes. I had a drill bit that was almost exactly the diameter of the
1" PVC connectors (4 of them). As you can see from the picture there are 2 on each side. Each one of these 20 cent PVC items house 2 inline skate wheel bearings. Before you can mount these on the support you need to ream them out a bit to receive the bearings. I used my Dremel drill with a sanding tool. It kicks off very annoying PVC dust so do this little task where you are not going to make a mess.

So, now you've reamed out the 4 PVC connectors and pressed the bearings in. Two per piece adding up to 8 bearings in all.
On to next step....

Step 4: Mounting Bearings

The object here is to mount these pieces of PVC in the holes you drilled in such a manner to give your boom an nice bearing surface to move on.
Before you can mount cut 2 6" pieces of your remaining 5/16" threaded rod for your axles. By the way, 5/16" is the exact ID of the bearing.

Were going to epoxy these parts in place but before you do put each part in the support with the axles inserted. This way you can get perfect alignment. The PVC parts should go half way in with a bearing on the outside and a bearing on the inside. Make sure you you have at least 1-1/8" clearance or you wont be able to insert the booms.

Once you are happy with fit and alignment do the epoxy thing and reassemble WITH the axles inserted.

On to next step...

Step 5: Mount Support to Base

In my case I cheated and used my Celestron yoke to hold the boom support subsystem.
I just removed the telescope and positioned the support subsystem and drilled a single hole through everything. I had to jury-rig the assembly as the dilling was not perfect. But it is stable.

If I didn't have the Celestron option I think I would have proceeded to use an ABS end cap and mounted it to the wooden top of our base. I think it would be strong enough. I would have used 3 or 4 1/4" bolts with very large washers. I doubt that you would even need to use ABS cement. Once it is in place on base I don't think it would go anywhere.


We have built and assembled the base unit
Lay out and drilled the support column
Assembled bearings and axles
Epoxied axle system in place
Created a way to attach support subsystem to base.

Step 6: Boom Parts

There are four parts to be fab'd before we can do final assembly:

2 end caps made out of 1-11/4" angle aluminum
2 booms made from our 2 10'x 1-1/8" pieces of conduit

End caps-
The end caps will have 2 axles on 5-1/4" centers w/o bearings.
I cut 4 pieces 7-1/2" each.
I then fit the pieces to form a U so ends of boom will be contained inside. Just looks neater. I've seen some booms where someone used a piece of 1"x1" metal and attached with bolts leaving the boom ends exposed.

Once you formed the U find center and drill 2 1/4" about 3" apart. I used 1/4" counter-sunk machine screws with lock washers and nuts on inside.

Pick one of these end caps to be your camera end. If you have acquired a pan head to mount camera on you will need to drill a 3/8" hold to bolt up the pan head to the end cap. Center it and drill it.

On the sides you need to drill 2 5/16" holes for the axles. These, too, are on 5-1/4" centers. I made them 1/2" from the back of the U so everything is pretty well centered and looks clean. This did require one more minor step that I will cover in the boom fab portion of this step.

I believe the boom sections are the hardest part to get perfect. Here's why:
You need three sets of 5/16" holes perfectly aligned with the holes through the widest part of the conduit.
I do not have a machine shop so I was left to my own devices as to how to do this.
I first found the middle of the conduit I was using. I chose to have booms only 8 foot long. I don't need the extra 2 feet as my camera shots are to be all close ups and of miniature stuff.

Center one hole at 4 foot mark, the other 2 at the ends 1/2" from the end.

To center I used my laser picture hanging tool. For the center I used a piece of tape with a very small nail pushed through so the laser had something to shine on. The close end was easy. The far end was a problem as laser spreads a bit. I used a piece of paper behind end of conduit and it lit up the end.
To drill I used my neighbor's drill press. I used a jig to hole conduit so I could get both sides of conduit drilled at same time.
All holes came out perfect.
I used a file to cleanup holes.
One last step is to chamfer a bit off of the ends of the conduit. If you don't the conduit will be constricted as soon as angle of boom hits the end caps.

I think all of the parts are complete.
Next final assembly...

Step 7: Final Assembly

Attach your support system to the base. I used 1/4" x 2" bolts used to assemble computer tables. They get tightened using an allen wrench.

Next, insert one of the booms into lower bearing position. You will have a bit of space between the inside bearings. I inserted the axle then added a 5/16" nut, screwed it through to the opposite side of conduit and added 2nd nut.. After centering using a couple of wrenches at the same time, I finished off using 5/16" aircraft self-locking nuts. Don't use a washer as it will defeat the bearings.

Next assemble end caps using 5/16" x 2" bolts or you probably have some of the threaded rod left over. Just put it together for fit. If everything works ok then we can do final.
I used some neoprene washers between the boom and the end caps just to make it smoother.
Don't tighten too much. I used the aircraft nuts here.

Final step is to mount your camera pan head using a 3/8" by 3/4" bolt with large flat washer. I had to cut down the bolt as pan head didn't go deep enough. Use a file to clean up thread for easy camera attach.

Lastly, you will need to make something to hold ballast as a counter weight. I'm going to find something and fill with sand.
No, it wont be out of the cat box.


dancook made it!(author)2008-01-17

Great Job! The jib is pretty much identical to an industry construction, by taking a fluid head mounted to the arm (possibly in a rubber boot) you can pan and tilt as per a commercial boom arm. As you probably already know a jib is used to get sweeps and nice gentle movements in the cameras position, all the camera targeting is usually done at the camera head itself. This is where you have a cameraman operating the camera (and camera head), a jib operator controlling the jib arm itself and a dolly puller who rolls the rig (if tracked or wheeled). just to add more people you could also get a focus puller, but that may get a little crowded for your use? Cool rig though, might have to pop down to the garage to make one myself....

mothflavour2 made it!(author)2007-03-12

Here's how you can keep the camera pointed at one point (like someone's face maybe): Make the distance between the metal bars a bit wider at the ABS pipe than the camera mount, so the pipes aren't parallel. This way, when you raise the camera up, the bottom metal pipe will at a steeper angle than the top pipe, causing the camera to tilt down a bit. The opposite is true when the camera is lower; it'll tilt up.

cinepeg made it!(author)2007-06-14

It will tilt in the right direction, but not at a rate that will keep it fixed on any single point.

Think of it this way: the counter-angle of the camera is proportional to the angle of the crane, multiplied by the width of the crane's end, divided by the width of the the camera's end. So, when both ends are equal, then the camera's counter-angle exactly balances the crane's angle, keeping it parallel.

If the camera's end is shorter, then it will point down the further up the crane goes. But when the crane is straight forward, the camera will be straight forward, too. So imagine that horizontal line along where the camera is aiming, and think about where the camera's aim will converge with that line as you raise the camera.

As the camera's angle increases, it will converge with that line at a point further and further back. This shows that there is no single point that the camera will always be aimed at.

Of course, it might still be close enough for your purposes, or it could be used to follow someone walking towards or away from the camera.

Also, here's another crane:

cinepeg made it!(author)2007-07-07

This was bugging me, so I made a graph. Vertical is the angle from a point 2 metres away to a camera on a 1 metre crane. Horizontal is the angle of the crane, for red, and the height of the camera, for blue. For the simple "make one side of the crane thinner than the other" method to work, the red line would have to be straight, not curved.

kentek made it!(author)2007-03-13

Nope, just keep them parallel. In fact, I was toying with what happens when you point the camera straight down? I want to have a stationary object below and pan down to the object so you would feel the object is raising up to camera. I thought that there would be some movement because of the arc of the boom. But, in fact, you have two arcs revolving around a single point(the camera) and they cancel out. Make a model with a 1/4" dowel. Just use pins to hold everything together. The center point is the key.

nagutron made it!(author)2007-03-12

That's a great idea. Additionally, if you make distance between the hinges adjustable (on either the camera end or the operator end), you'll be able to set the point at which the camera will always point.

sam made it!(author)2007-03-13

Did you say super 8? Are you filming with a super old school film camera?! Do they still make and process film for that? Also- I think there is some confusion about the bars? From what I understand, your boom will always stay "level" due to the same arm length. As you move it, it would not be pointing at the same spot. You could also set it up with different arm lengths, and have the camera tilt down as it moves up, and vice versa, so it would always point at the same place, but from different heights, and without staying "level"

kentek made it!(author)2007-03-13

Yep, Super 8. I now have 5 cameras. Four off eBay and the original one my Dad gave me in the '60. Huge resurgence of Super 8 world wide. The one on my boom is a circa 1980 French Beaulieu 3008S. It is very nice, near mint. It is also my most expensive: $475. My cheapest was a nice little NIZO for $36. So, the averages are resonable. Take a look at if you have more interest in S8. RE: I can keep any angle on the Camera by changing it at the pan head. The option I would like to add is a servo motor control. I can get one for about $160. What you want is something that will stay steady on a target. That is possible but I think it a bit pricey. Some of the big sports video guys have the technology to do that. I think they use a laser tag with something on the rig that follows it. I have a contact that I can get more info. Changing the booms would be a PiA. . Thanks for responding to my 1st effort on this site.

trebuchet03 made it!(author)2007-03-12

I started building this project without the idea of making it an Instructable

No worries :) Better to share than not at all :P

Now does the camera stay level all the time while in operation? I'll bet with a little thinking (and a pen/paper) you could figure out the right level lengths to keep the camera always pointed at the same point. If I missed that in your posting, my apologies :P

Hermes made it!(author)2007-03-12

His design will keep the camera level. The two arms connected to the camera support piece are hinged so as to keep the end always perpendicular to the ground. This ensures that the camera will always maintain the angle it is positioned at. Hope I made a little sense... ~Hermes

trebuchet03 made it!(author)2007-03-13

Yep, I see that it's hinged and all... I was just curious on how he set the lever :P Thanks :)

kentek made it!(author)2007-03-12

Thanks for the help. Still some Instructable issues to iron out. I have more images that I will add soon.

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