Dolly wheels and tracks

[Adam Paul]

I have had a tire dolly for a while now and I want to convert it to a track dolly. I have found some U grooved steel wheels covered in polyurethane inside the groove for silence. I have also found the track that goes with it. It?s not purposed to be dolly tracks but it seems it could work. My only concern is that the wheels and tracks are pretty slim. The wheels are 120mm in diameter and only 30mm wide. The groove itself is only 21mm and the round track is 20mm diameter. The weight is not the problem. They support up to 470lbs. But do you think it will run smooth even being so slim or it doesn't matter? Would flanged wheels on a square track be better than the U grooved wheels on round tracks? Thanks.

Edited January 30, 2007 by Adam Paul

[Adam Paul]

36 views and no reply? Comon guys, help me out here :)

[Adam Paul]

Should I post the question in the 35mm forums? :(

Maybe I will have better chances to get a reply there as there are more people visiting.

[Hal Smith]

Should I post the question in the 35mm forums? :(

Maybe I will have better chances to get a reply there as there are more people visiting.

I suggest being much more specific with details: make and model of dolly, post a couple of pictures, etc.

[Adam Paul]

No make and model. It's a self made tire dolly. It's about 34"x64" and made of plywood, steel and aluminum. It has four 8" tires on right now. The go-kart looking type of tires. I would like to convert it to a track dolly. I have two options for that:

 

Option 1: 125mm diameter (flange is 150mm dia.) x45mm wide flanged wheels over 30x30mm square tracks

 

Option 2: 120mm (100mm inside U) x 30mm wide U grooved wheels over 20mm diameter round tracks.

 

The bonus of option 2 is that the tracks are already ready and in option 1 I would have to build the tracks. Option 1 would also be cheaper.

Both options are polyurethane covered steel wheels with double ball bearings for smoothness and silence.

I'm wondering what's the best option and what's best, square or round tracks? Are the wheels in option 2 too thin? Will they be unstable or not smooth enough?

If both options would be the same I would rather go with option 2 because the tracks are already ready to use. But if a flanged wheel would give extra precision and smoothness over a U grooved wheel and if 30mm wheels or 20mm diameter tracks are too narrow to be stable and or smooth, I would go through the extra work of building the square tracks and just go with the flanged wheels.

Thanks.

[Hal Smith]

No make and model. It's a self made tire dolly. It's about 34"x64" and made of plywood, steel and aluminum. It has four 8" tires on right now.

Axle diameter? If you're lucky, and your axle diameter is standard, you can probably use standard dolly wheels.

[Adam Paul]

Axle diameter is 20mm. Both wheel models come in 20mm center hole.

[Alain J Francois]

I have had a tire dolly for a while now and I want to convert it to a track dolly. I have found some U grooved steel wheels covered in polyurethane inside the groove for silence. I have also found the track that goes with it.

HI, the system you describe has been used out in the field by ABC camera operators for years. It seems to work perfectly for short dolly distances. If you required longer tracks it becomes a problem where you have to join the tracks. Also, I have seen operators place old mats under the tracks if the ground is uneven.

Cheers, Alain.

[Adam Paul]

HI, the system you describe has been used out in the field by ABC camera operators for years. It seems to work perfectly for short dolly distances. If you required longer tracks it becomes a problem where you have to join the tracks. Also, I have seen operators place old mats under the tracks if the ground is uneven.

Cheers, Alain.

 

Hey Alain, thanks for the reply. Finally some input :)

 

Why is joining tracks a problem? If the joints are smooth I can't see a problem, or is it related to something else?

By the way, the system you say ABC uses is the U grooved wheels? With the particular ones I found I'm just afraid they may be too narrow at 30mm and the tracks at 20mm diameter.

[Mitch Gross]

Check willyswidgets.com to see what other setups are like.

[Adam Paul]

Check willyswidgets.com to see what other setups are like.

 

Thanks for the link. I checked their site and they only have the small skate wheels. A very different set up to what I have in mind. What's your opinion on my option 1 vs. my option 2 and the stability and smoothness questions?

Thanks.

[Adam Paul]

I decided for the U grooved ones. Looking at some high end dollies in some big budget movie making ofs they seem to have pretty small single wheels and be smooth enough to carry even big jibs so should be fine for me. I think 120mm is more than big enough.

 

Thanks for "all" the input.

[David Auner aac]

I decided for the U grooved ones. Looking at some high end dollies in some big budget movie making ofs they seem to have pretty small single wheels and be smooth enough to carry even big jibs so should be fine for me. I think 120mm is more than big enough.

 

Hi Adam!

 

I'd be interested in your experience with your selfmade dolly. Can I see some pictures/drawings?

 

Thanks in advance, Dave

[Adam Paul]

Sure thing. Once I'm done with the project I will post pictures here.

[David Auner aac]

Sure thing. Once I'm done with the project I will post pictures here.

 

Do you have any pictures of it in tire config?

 

Cheers, Dave

[Adam Paul]

Do you have any pictures of it in tire config?

 

Unfortunately no, sorry. But it doesn't look much different than the Western dolly.

[Adam Paul]

Just got off the phone with an old friend who was trying to stir me towards going for skate wheel trucks. He mentioned people are putting even Fishers on skate wheels those days. :blink: (although I wonder why)

 

 

Just when I was finally set on single U grooved wheels. :(

[Adam Paul]

Isn't there any pro grips with experience in the field who could atually give some insight? I have given enough details but I still didn't get any solid input. I'm now having seconds thought between going with them little skate wheels or going with the U grooved wheels set up I mentioned above. I wonder what advantage is there with skate wheels because people seem to be putting Fishers on skate trucks even though Fisher is a track dolly and has it's own track wheels.

[Onno Perdijk]

Hello all,

 

There is a lot to comment on this topic, nearly to much to start doing it. here is a try

First the advantage and disadvantage of U-grooved wheels: The andvantage is the shape wich will prevent de dolly from sliding of the track. T

The disadavantage is hard to explain for not being native-english: If you'd take a slice-cut (cross-cut?) of the wheel on the track you will see that a U-wheel touches the round-track nearly everywhere. (if this is not the case please neglet this post). The rotation speed of the wheel is everywhere the same, (say 12 rounds per minute) wheater you are on point A or B. The surface-speed however is different, since in one rotation of the wheel, point A needs to clear a distance of say 18 cm, point B needs to clear 12 cm and point C is nearly in the centre of the wheel and does need to clear les the 1 cm. This difference in surface-speed creates internal-forces in the material (rubber, nylon, ...) of the wheel. If the material is not soft enough it will be torqued (split). To prevent the outher side of the will from having this surface-speed people tend to use WD40 or teflon or other kinds of lubrifications. This will let the wheel glide instead of roll.

So for U-wheels you will need very soft material or loads of WD40 or silicone-spray on the tracks. Soft wheels tend to flatten on a heavy payload. The lubrifications gives a dirty track.

 

Concerning the heavy dollies on scateboard wheels:

The scate wheels are flat on the track so no difference on surface-speed.

The more wheels to carry the payload, the less resitance on the track.

The more bearings to run each wheels, the less resistance. Although with a long line of scate wheels on a row it is hard to push the dolly through a (narrow) curve.

With a line of scate wheels the weight of the dolly is evenly distibuted on the track, so if you have a track-joint the dolly will have just two wheels at the same time hitting the joint. The other wheels are still running smoothly and carrying the weight.

 

Hopefully this helps.

 

Onno Perdijk

Amsterdam, The Netherlands

KeyGrip

crosscut.bmp

[Adam Paul]

Hi Onno,

 

Thanks for the explanation. So it seems four trucks of 2 wheels or even four trucks of 4 wheels would be better than 4 bigger U-groved wheels? I was always wondering what's the point in putting a Fisher dolly on cheap/homemade looking skate trucks.

How about flanged wheels(the type similar to the ones used in trains). They don't seem to have difference on surface-speed either.

By the way, the U-grooved wheels are polyurathane covered, so I think they should be soft enough(?)

[Onno Perdijk]

Wheels like they use on trains (here in holland) run flat on the tracks. The sides hit the tracks as well. When using them on a filmdolly you will either have "the difference of surface speed" between the sides and the running-surface of the wheel or you will have the side of the wheel sometimes touching the track which will result in more resitance for the dolly-grip, so a non-continues unpredictable speed change.

 

The flanged wheels on the fishers, hybrid and peewee do have a little "track-rounding" so in theory the should have this surface-speed-thing, on set you will not encounter them this much.

 

Onno Perdijk

Amsterdam, The Netherlands

KeyGrip

[Adam Paul]

Wheels like they use on trains (here in holland) run flat on the tracks. The sides hit the tracks as well. When using them on a filmdolly you will either have "the difference of surface speed" between the sides and the running-surface of the wheel or you will have the side of the wheel sometimes touching the track which will result in more resitance for the dolly-grip, so a non-continues unpredictable speed change.

 

The flanged wheels on the fishers, hybrid and peewee do have a little "track-rounding" so in theory the should have this surface-speed-thing, on set you will not encounter them this much.

 

Onno Perdijk

Amsterdam, The Netherlands

KeyGrip

 

Yeah, that was the basically reason I decided on the U-grooved wheels over the flanged ones. The flage would touch the tracks. But given all you said it seems the skate wheels are a better solution than the U-grooved ones. I have been looking around online and there seems to be a lot of people using them. I even saw that they used some in King Kong. Funny because I would have never thought they would be better than the U-grooved wheels or the Fisher wheels because both styles seem to be more precise. Panther even have them and call them precision wheels or something. Go figure.

Now it's just a matter of deciding between trucks of 4 skate wheels each or is there a need for more wheels per truck?

Edited February 13, 2007 by Adam Paul

[robert duke]

Yeah, that was the basically reason I decided on the U-grooved wheels over the flanged ones. The flage would touch the tracks. But given all you said it seems the skate wheels are a better solution than the U-grooved ones. I have been looking around online and there seems to be a lot of people using them. I even saw that they used some in King Kong. Funny because I would have never thought they would be better than the U-grooved wheels or the Fisher wheels because both styles seem to be more precise. Panther even have them and call them precision wheels or something. Go figure.

Now it's just a matter of deciding between trucks of 4 skate wheels each or is there a need for more wheels per truck?

 

 

Check out Modern studio or willey's widgets. They have eight wheels per truck. the more wheels the more the load is spead and the more capacity for the dolly. I have a door way set with four wheels per corner, it runs fine for loads on a doorway dolly. I have a set of modern skate trays with eight wheels per corner. I use this with fischers and chapman, I also use this with the panther dolly. I have even begun for speed sake using the dolly trays with the doorway dolly rubber wheels so I dont have to take time to switch wheel sets.

 

Losmandy makes a set of trays with different diameter wheels so that even with high loads when the wheels get a flat spot the varied diameter smooths out the ride to hide the bump. I usually just rock the wheels out just before the shot.

 

your u shaped wheels will work. the panther has them and the fisher and chapman have them as options. I only use the panther set on straight track. It squeaks like the dickens on round track. I never use the fischer or chapmans bc I have a set of dolly trays. These make life faster and less worries about dirt or gravel in the wheel. The panther u wheels seem to tear up frequently because of dirt and rooling on hard floors, which is why I dont like the panther as a dolly. ( I know there are fans of it)

 

Build your dolly the way you want it. experiment. If you have the wheels make one of each and find the one you like. If it works great let us know, it might be your million dollar idea.

 

Robert Duke

Key Grip

Memphis,TN

[Adam Paul]

Thanks for the very insightful reply Robert.

 

Check out Modern studio or willey's widgets. They have eight wheels per truck. the more wheels the more the load is spead and the more capacity for the dolly. I have a door way set with four wheels per corner, it runs fine for loads on a doorway dolly. I have a set of modern skate trays with eight wheels per corner. I use this with fischers and chapman, I also use this with the panther dolly.

 

My dolly is a doorway type of dolly too. Much like the Western dolly. But I have a pedestal where I can mount either a tripod head or a jib arm. So the load is not so light. In this case would you advise going with more than four wheels per truck? I don?t know how much a fisher or Chapman weights but I would think my dolly even with the jib arm wouldn?t weight as much as one of them.

 

 

I have even begun for speed sake using the dolly trays with the doorway dolly rubber wheels so I dont have to take time to switch wheel sets.

 

If I really go for skate wheels this is my plan. To make a tray where I can just sit my dolly on without taking the rubber tires off. It really seems to save time that way.

By the way, are the skate wheels found in hardware stores good enough for this? Or should I go to a proper skate shop? Also, am I looking for harder or softer wheels here?

 

Losmandy makes a set of trays with different diameter wheels so that even with high loads when the wheels get a flat spot the varied diameter smooths out the ride to hide the bump. I usually just rock the wheels out just before the shot.

 

That?s a good idea to have different diameters.

Rocking the wheels sound very useful specially on a cold day I would guess.

 

your u shaped wheels will work. the panther has them and the fisher and chapman have them as options. I only use the panther set on straight track. It squeaks like the dickens on round track.

 

I was only going to use it for straight track as I don?t think I can build a round metal track and a PVC one doesn?t sound would be very stable, or?

Anyways, the skate wheel tray will work on a round track? Or it needs to be pivoting trucks to work on a round track?

 

 

I never used the fischer or chapmans bc I have a set of dolly trays. These make life faster and less worries about dirt or gravel in the wheel. The panther u wheels seem to tear up frequently because of dirt and rooling on hard floors, which is why I dont like the panther as a dolly. ( I know there are fans of it)

 

Yeah, the main reason I was going for the U grooved type of wheels was because all the big pro dollies use them and because I thought the bigger diameter would smooth the ride more than the little skate wheels. I guess I was wrong. I was really surprised to see Panthers and Fishers on skate trays in big budget film sets.

 

Build your dolly the way you want it. experiment. If you have the wheels make one of each and find the one you like. If it works great let us know, it might be your million dollar idea.

 

That?s a sure thing. I will post the results here when done.

By the way, I see you are in Memphis. That?s a lovely city. I have been to Memphis in May once. Great place really. I love the Southern hospitality.

[Adam Paul]

Losmandy makes a set of trays with different diameter wheels so that even with high loads when the wheels get a flat spot the varied diameter smooths out the ride to hide the bump. I usually just rock the wheels out just before the shot.

 

I was just thinking about the flat spot problem with skate wheels. Would the U grooved ones have the same problem? They are steel covered in polyurethane type of material.

Also, I just checked Modern Studio and I see their standard wheel set are soft and the luxury set are hard wheels. I thought soft wheels would be smoother and the only advantage of harder wheels would be no flat spot. But at the cost of smoothness?