Rowe Cine LLC: Professional Cinema Products

Dolly Information, Tips and Tricks
last updated: 3-28-07 2:14pm

1. TRACKS

A. Types of track

When considering the type of track you will use it is important to understand the potential advantages and drawbacks of the options at hand. Mainly, there are two types of tracks used - Metal and PVC. We recommend that you read the entire section 1 which details important things to know about the different track options.

Metal track.

Metal track is most commonly made of either stainless and/or plated steel, or aluminum. Steel track is stronger than aluminum but also costs more and weighs much more. Metal track commonly uses supports or trusses called "cross members" (much like a railroad track uses) to support the track off the ground surface and firmly hold the track in its spacing and position. Standardized professional metal dolly track has a diameter of 1.5 inches, and is set at 24.5 inches apart center to center between tracks. Although this is the standard, metal track can come in any diameter, and have different center to center distances as required by the specific dolly applications. For example if you were using a very small portable dolly, you would not want to have to use a big heavy track, and a smaller diameter track with a distance of 12 to 18 inches between tracks would be better suited. As compared to PVC, quality metal track is the track of choice due to it's superior load capacity without flexing, smoother surface and track connections, superior ability to resist wear and tear, ability to be "bridged" without support under every point and easy cleanup. The drawbacks of metal track as compared to PVC are it's higher cost, increased weight, the precautions needed to preserve the track and increased setup times.

PVC

PVC (short for polyvynilchloride) is a type of plastic/vynil piping most commonly used for structural plumbing applications. It is found at most hardware and building supply stores. It is very cheap, and can be connected together to form long lengths of inexpensive dolly track quickly. The most common type of this "track" used is schedule 40 1" thick walled high pressure PVC. This type of PVC most commonly is white in color and has thicker walls than standard 1" schedule 40 PVC. For this type of track, 3/4" galvanized or coated metal close pipe nipples can be used as simple screw in track connectors. these can also be found at hardware or building supply stores. Using a 3/4" pipe threaded plug end and a wrench, the plug can be screwed into the ends of the PVC causing it to cut threads into the end of the PVC track. After screwing the plug in and out of the track and a few times it will leave threads in the PVC where the screw in connectors (close pipe nipples) can be threaded in by screwing two sections of track together on it it opposite directions threading them onto the close pipe nipple until they are pulled together snug. When used as dolly track, the thicker walls of the high pressure type PVC allow increased weight to be carried on it without deformation of the round shape of the pipe. If thinner walled PVC is used, it could deform under the weight of the dolly and cause unwanted noise from wheel "pinch" or other unwanted issues. As compared to Metal track, PVC can be a great alternative option as it is lighter, very cheap, quicker to setup and teardown, and expendable. The drawbacks of PVC as compared to metal track are it's weak support strength (it needs support such as level ground under every point of track, because it cannot support weight over spaces), its surface is prone to scratches and cuts from abrasion with harder ground surfaces, it picks up small dirt and debris from its static charge which makes it sometimes difficult to keep clean, and it is harder to align track connections perfectly straight.

B. Track setup.

Setup for metal track

Metal track generally comes with its own instructions for setup according to the manufacturers recommendations and specifications, but there are always some additional considerations to consider. Be sure to keep your track out of direct contact with dirty or abrasive surfaces as the track could get dirty or scratched/dented. Set your track up on level ground, or create a level surface for it to ride on. Shims (most commonly small wooden shims found at any hardware or building supply store) may be used to level sections of track by placing them under the support sections or cross members where the ground is uneven. Strips of carpet or similar material can be used to lie down under your track to keep things like grass, weeds, or other similar things from coming up onto or over the track when you are on brushy terrain. When grass or weeds gets onto the tracks it can not only cause un smooth motion, but it can get the track and wheels dirty as the wheels and track squish it up between them. Carpeting or similar can also be used to keep the tracks off of dirty or abrasive terrain. This can also reduce or remove ground noise if you are using PVC directly on a terrain which can shift under weight like gravel.

Setup for PVC track

PVC requires smoother and more level surfaces than metal track because it cannot bridge small gaps, and does not hold its own ridged alignment well. Filling in small areas of low outdoor ground with small rocks (such as fish tank rocks or assorted cleaned river rocks) is an easy option to keep a level and solid surface for your PVC track. Strips of plywood can bridge small gaps while carpet or similar material can be used to lie down under your track to keep things like grass, weeds, or other similar things from coming up onto or over the track when you are on brushy terrain. When grass or weeds gets onto the tracks it can not only cause un smooth motion, but it can get the track and wheels dirty as the wheels and track squish it up between them. Carpeting or similar can also be used to keep the tracks off of dirty or abrasive terrain. This can also reduce or remove ground noise if you are using PVC directly on a terrain which can shift under weight like gravel.

C. Track maintenance.

Keeping the tracks clean.

Almost every common issue with noise or un smooth dolly movement comes from the tracks being dirty or worn. This is something that must be taken into consideration when using PVC, especially when using it in environments where dirt, dust and grit are coming into contact with the track. PVC has the ability to pick up and hold a considerable static electric charge, and is prone to having any small debris (up to grains of sand) stick to it when it is laid along the ground. Because of this there should always be a dry, or damp cloth on hand to wipe down the tracks between critical shots or takes. keeping the tracks clean will also mean that you will not have to clean your wheels as often since the track will not be transferring debris to the wheels when the wheels are on the track. using a damp cloth will lessen the chance that you are INCREASING the static charge of the track by rubbing the cloth or towel on it when cleaning. However, you should not have a wet track if possible, so be sure to have only a damp cloth which is not leaving too much moisture on the track. especially if you are using metal track. Metal track should for the most part be kept as dry as possible. Some people like to use PLedge or other waxy sprays on their track in order to lessen any sticky points which could cause squeaks. While we here at Rowe Cine LLC do not utilize these methods, they are always handy if you have tried the regular cleaning of the wheels and the track. remember that if your needing to clean the track often(as common with PVC), chances are that you should also clean the wheels. The track will transfer the debris to the wheels and actually occasionally embed small pieces of grit onto the wheels if there is enough weight on the wheels as it goes over the dirty track. Using a dry or damp cloth you can clean the "dirt ring" off of each wheel where the wheel has come into contact with the dirty tracks.

How to handle, care, and maintain the track

When it comes to maintaining PVC, We recommend that you simply replace your used PVC track as often as possible unless it is only used in clean and smooth environments where it stays clean and does not get scratched up. Scratched, dented, worn, or dirty PVC is not worth keeping and can only hurt a shot as compared to newer, smoother, cleaner track. You can check your PVC track for smoothness by running your hand along the surface. If there are scratches and debris, you will feel it easily. For metal track it is important to keep it clean and keep the inside of its case (if one is used) clean as well so that you do not have to clean it when taking it out of its case. Caution should be taken with metal track to not damage the ends of the track where the track connections are made. This is especially true for lightweight aluminum track as it is damaged more easily than steel track. If possible, then inside of the track carrying case should be padded at the ends to protect the connecting ends, and the track should be bundled together to keep it from rattling against itself when in transit. Metal track should also not be set down directly onto hard abrasive surfaces such as cement or gravel or metal grating. While your metal track really shouldn't be set down directly onto any dirty surface because it could get debris onto the track, the abrasive surfaces could also potentially scratch and/or dent the surface of your metal track.

Track Tips and Tricks

When using a dolly with metal or PVC track there are some easy track based solutions to getting things done more efficiently, solving common issues, and overcoming common obstacles. We hope that these ideas help you get the most out of your dolly and time with it on the set.

When screwing PVC track together have the connecting ends lying flat on the ground and have someone step on one connecting end of the PVC and have the other person twist the other PVC close to the ground from the back end which is away from the connection until the connection is tightened. this will help the PVC be screwed together straight, as the ground acts as a guide for the PVC forcing it to be leveled a the connection. It also allows the person screwing the track together to view down the track to the connection to see if the angle of insertion is straight.

Always keep the tracks and wheels clean. A damp cloth is perfect for cleaning off the tracks and wheels. Try to use only water instead of any cleaning agents or materials, and avoid using items like Pledge or similar products for cleaning unless it is a proven method which you have found works for your dolly and track.

Strips of carpet or similar material can be used to lie down under your track to keep things like grass, weeds, or other similar things from coming up onto or over the track when you are on brushy terrain. When grass or weeds gets onto the tracks it can not only cause un smooth motion, but it can get the track and wheels dirty as the wheels and track squish it up between them. Carpeting or similar can also be used to keep the tracks off of dirty or abrasive terrain. This can also reduce or remove ground noise if you are using PVC directly on a terrain which can shift under weight like gravel.

Plywood makes an easy simple leveler when you have patches of uneven ground.

GETTING RID OF SQUEAKS, CLICKS AND POPS. Using talcum powders, or waxy sprays such as "Pledge" can get sometimes get rid of any squeaks as a quick fix, but you should ALWAYS test this out BEFORE being on location, to know what solution, if any works or is needed with your dolly and track setup. DO NOT use these items to try and alleviate clicks or pops, as clicks and pops are not caused by wheel and track stick, but almost always cause by dirty track and wheels. Clean your wheels and track thoroughly. Refer to tips #2 and 3. You should also check the construction of your dolly to be sure that the noise is not coming from the dolly itself under weight. You can check this by walking on the dolly on a CLEAN set of tracks with CLEAN wheels on carpet or other similar material. If the dolly is squeaking or clicking and popping from your weight shifting on it you should tighten, or loosen (pending your dollies construction)the appropriate points to get rid of the noises. If you have constructed your own dolly, check to make sure that the wheels are in proper alignment. the center of the wheels on the front of the dolly should be the same distance apart as the center of the wheels at the back of the dolly (in other words, the wheels should be perfectly parallel to ride on parallel tracks). If these distances are different, the wheels will try to pull the track in odd directions as it travels over it which can cause unwanted noise.

If your dolly is experiencing bumps over connections, it is either an un straight connection , it has debris in the connection, or the ends of the PVC are not square (it has rounded edges on the PVC from wear (or metal from damage) which can cause a small dip in the track if both edges are rounded too much). Replace, clean, or reconnect the track as needed once the issue has been identified.

Filling in small areas of low outdoor ground with small rocks (such as fish tank rocks or assorted cleaned river rocks) is an easy option to keep a level and solid surface for your PVC track.

Check back for additional and/or updated information, tips and tricks soon!