Step 1: Materials
• 18m x 50mm diameter hard PVC tubes
• 2 x T-section tubes, 50mm diameter
• 8 wheels, ideally rollerblade wheels with screws, bolts and washers
• 3m of plywood
• Some sort of shock absorbing material: foam, yoga mats or springs.
Optional (for dolly track rails)
• 6m of plywood
• 2m of 2x4 wood
• Strong glue
Tip: Ask your local hardware or furniture store for their wood leftovers.
Step 2: Tube Lenght: Step 1
Decide on how long you need your track to be for the shots you need. Double that amount.
Example: I need a dolly of 6m: I need 12m of tube.
Tip: You can always make the track longer afterwards.
Step 3: Tube Lenght: Step 2
Example: 12m of tube divided by 1m50 pieces, is 8. 8 x 30 cm= 2m40
Tip: Make your joints long, but not too long that they make your life harder in transport.
Step 4: Tube Lenght: Step 3
ï§ a = 75cm, rounded up to 80cm
ï§ b = 66cm, rounded up to 70cm
ï§ Total: 1m50
Tip: Rounding up will give you more flexibility for the use of other tripods. Round numbers are easier to work with.
Step 5: Tube Lenght: Final Step
Example: 12m + 2m40 + 1m50 = 15m90 + a bit of extra: 18m
Tip: Keep a good relationship with your shopkeeper. Our tubes were sold in lengths of 3m, so we bought 6 so he wouldn’t have to cut one.
Step 6: Sawing and Measuring: Step 1
Ours had one thick and one smaller ending, so we had to adapt ourselves. If your tubes have both endings the same, some steps will be much easier for you. Some hardware stores might sell tubes with two small ends, but our stores in Venezuela only sold these.
Same applies to your T-sections: ours had to connect on two sides to the small end and on one end to the big tube end, which made a difference in the sawing and measuring.
Put two tubes aside. Cut the other larger tubes in the lengths you want for your track part.
Example: 4 tubes of 3m, cut in pieces of 1m50 = 8 track parts
Tip: Mark these as being your tracks, not to use them accidentally for something else.
Step 7: Sawing and Measuring: Step 2
You should have two tubes, each with a big end and a small end. Now, saw those two in half, mark them as dolly cart parts and put them aside.
Take what’s left of the two tubes. Saw off the centerpiece of the cart with two small endings. Mark it and put it aside with the other dolly parts.
Example: Our tripod measured, rounded up, 70cm in between. That’s the length of the centerpiece.
Step 8: Sawing and Measuring: Step 3
Step 9: Sawing and Measuring: Step 4
The rest will be used for testing. Mark and put aside.
Example: 8 track parts, require 6 joints of about 20cm. We should have 60cm of tubing left for tests.
Tip: Weigh for yourself how long you want your joints to be: longer will be more stable, but will also be more difficult in transport.
Step 10: Sawing and Measuring: Final Step
Step 11: Wheels: Step 1
Before you start drilling for the wheels, keep in mind:
a. Put them a few cm’s away from the tube opening. It’ll be easier to handle.
b. Don’t drill the holes opposite to each other. Leave some space, so the screws won’t touch each other in the tubes.
c. Both of your wheels need to touch the track underneath, while keeping a good contact surface with the dolly cart tube.
Step 12: Wheels: Step 2
Do this for all the 4 dolly cart tubes.
Step 13: Wheels: Final Step
Step 14: Gluing: Step 1
Align the wheel lines you made earlier with each other, over the T-sections.
Test on the tracks with your tripod, until you’re satisfied that all the wheels touch the tracks and roll as intended.
Step 15: Gluing: Step 2
Step 16: Gluing: Step 3
Tip: To create extra joints, make some of the test tube which you won’t use anymore.
Step 17: Gluing: Step 4
Example: We taped two pieces of 80cm to each other in a T-shape.
Step 18: Gluing: Step 5
Example: We used a yoga mat.
Tip: The original designs uses springs as shock absorbers. However, we tested and didn’t manage to fit the springs correctly. Our test results were too bouncy.
Glue the plywood platform on top of the shock absorbing material.
Step 19: Gluing: Final Step
Step 20: Optional Rails: Step 1
Firstly, decide on how many rails you can make.
Example: We decided on 6 rails, because that was the amount of useful wood we received for free.
Step 21: Optional Rails: Step 2
Step 22: Optional Rails: Step 3
Don't glue just yet. Use tape to temporary keep the pieces of 2x4 in place, or ask a friend for help. Drive your dolly cart of the tracks and check if the wheels aren’t touching the wood. Adjust until they fit.