TT scale trains and models

That is also typical for Europe. Very often the shipping costs from the neighbor country is much higher as the value of the product. That way many people prefer the chinese shops instead of Ebay etc.

Those chassis are quite nice, just the speed reduction seems to be to small. For the modern motors we need a gear with over 1:20 reduction ratio. This cannot be achieved with belt drive. ( the worm gear has a reduction in TT around 1:8-1:12, that means the belt drive should have additionally at least 1:2 reduction.)

railtwister wrote:The BullAnt looks like a great little drive, but like most things TT, it has been hard to get in the past and appears to be unobtainable at this time. Even if it were currently available, the difficulty and cost of overseas shipping adds significantly to its price for anyone in the USA or Canada.

Shipping costs brings up another point. I have bought on eBay a few items from China where the price of the order included shipping to the USA, and that overall price was less than just the cost would be for return shipping alone should the item prove to be defective. On the other hand, shipping from some countries to the USA seems quite high, not counting the customs costs.

Bill in FtL

One more time for the folks in the back row....

That's why I suggest that it be made and distributed within North America.

And, once again, I reiterate that unless the big manufacturers see a robust TT cottage industry they're not likely to pick up the TT-torch.

I wonder what the owner of Hollywood Foundry would think of someone in North America producing his product here? Further, I do not see there ever being a “Robust TT cottage industry” here, simply not enough people interested, especially with today’s “ready to run” mentality.

Bill in FtL

Bill,

I wouldn't do an exact copy and I don't think they have a patent on modularity.

I also don't think that a North American competitor would hurt them since I don't think that they sell very many mechanisms on this side of the planet.

As for cottage industry. The On30 guys got started by selling tree stumps and ore wagons to each other.

krokodil wrote:Those chassis are quite nice, just the speed reduction seems to be to small. For the modern motors we need a gear with over 1:20 reduction ratio. This cannot be achieved with belt drive. ( the worm gear has a reduction in TT around 1:8-1:12, that means the belt drive should have additionally at least 1:2 reduction.)

What do you mean you can't get low reduction with a belt dive. Take a look a Nigel Lawton web site. Here's a link to his pulley and belt products. It looks like you can get up to 1.1 to 11 reduction.

http://www.nigellawton009.com/DriveComponents.html

Hey Tin goat, save your voice. One problem with many members here is they don't want to scratch build or can't. I've always liked the Hollywood Foundry drive system, it's the top of any drive system I've ever seen.

Bill in Fla. said:

I wonder what the owner of Hollywood Foundry would think of someone in North America producing his product here?

His drives aren't patented and it would be an international patent. And who says that it would have to be identical to his drives. Ideas can be taken from his design and improved on. One thing I would add would miniature ball bearings. I just wish I knew where one can get a good supply of gears.

So who's game to start building "look-a-like" Hollywood Foundry chassis and drive system? Motors can be gotten from North West Short Line.

http://nebula.wsimg.com/02d6e40c2d04190212ed400d3ccb2472?AccessKeyId=08BEE66B97B387F20C0D&disposition=0&alloworigin=1

They have expanded their line of motors. I see several that will fit. After perusing their web site I see they have expanded their gears they offer. So no complaining that you can't find a vendor for all the pieces we need to build TT scale chassis.

Bernd

Hi Bernd,

The things that I didn't want to scratch build are my own mechanisms.

I suppose I could though..

The lament I heard here is that there isn't a need for another loco shell until there are mechanisms to put under them.

That's the cottage industry we need.

Gears can be ripped out of old VCR's and DVD players or from the RC racers.

Sent from my SM-G903W using Tapatalk

TinGoat wrote:Hi Bernd,

The things that I didn't want to scratch build are my own mechanisms.

I suppose I could though..

The lament I heard here is that there isn't a need for another loco shell until there are mechanisms to put under them.

That's the cottage industry we need.

Gears can be ripped out of old VCR's and DVD players or from the RC racers.

Sent from my SM-G903W using Tapatalk

Well, we have to start somewhere. I'm some what set up for the chassis such as this one.

http://www.kingstonemodelworks.com/TTnut/GP38-2/TTchassis36.JPG

I never finished this build because I didn't have a motor. Now that I do I should restart this project. I'm looking at using a belt drive from the motor to the shaft that goes to ball joints. The two posts have miniature ball bearings to support the shaft. For those not mechanically inclined I'll explain why the ball bearings. If you use a belt drive like Nigel Lawton's the side pressure you get from the belt would put pressure on a plain brass or bronze friction bearing.

I wouldn't use gears from VCR's or DVD's. Perhaps RC cars, but those gears are to large for TT scale. One place that had small plastic gearing was Gizmozone. Their web site is shut down. I did also run across a place in Poland that sells gearing to the guys that are building HO scale R/C cars. North West Short Line has expanded it's gear line. They've also mention of custom cutting gearing. So I believe we have the recourses right here. We just need to utilize them.

Bernd

Bernd wrote:

krokodil wrote:Those chassis are quite nice, just the speed reduction seems to be to small. For the modern motors we need a gear with over 1:20 reduction ratio. This cannot be achieved with belt drive. ( the worm gear has a reduction in TT around 1:8-1:12, that means the belt drive should have additionally at least 1:2 reduction.)

What do you mean you can't get low reduction with a belt dive. Take a look a Nigel Lawton web site. Here's a link to his pulley and belt products. It looks like you can get up to 1.1 to 11 reduction.

http://www.nigellawton009.com/DriveComponents.html

Bernd

You can, you just do not have the space in TT. If the smaller pulley let us say has a root pulley of 2 mm the overall diameter will be over 4 mm
The second pulley must have root pulley of 4 mm, its overall diameter is 6 mm. This would be 1:2 ratio. Not very efficient as the belt on small diameter will tend to slip.
If you select bigger pulleys, like root 4 and 8 mm, you will be already almost out of space between the wheels because the bigger pulley will have an overall diameter of 10 mm.
The maximum space between the wheels is 10.2 mm.
I just wanted to point out the limitations of the belt drives in this form. Maybe you had a chance to have the Athearn RDC with beltdrive. It was a nice experience how not to build a model vehicle.

Additionally there is always a tension on both axles and on their bearings. That is why some people use ball bearings for beltdrives.

Guys!
Could you help me to find passenger trucks blueprints? In particular 41-n-11 truck. Or is there any source of blueprints on the internet?

krokodil wrote:The second pulley must have root pulley of 4 mm, its overall diameter is 6 mm. This would be 1:2 ratio. Not very efficient as the belt on small diameter will tend to slip.

Apparently you have never built a drive using belts. Nigel Lawtons belts are no where near what was used in the Atheran drives of yesteryear. Here's the start of a TT scale box cab I started. It uses an HO scale MDC Shay truck gauged to TT gauge. It uses a home made 5mm driver pulley to a 12.5mm driven. Look close and you'll see that the pulleys have a groove in them. It's a 45° groove for a square belt. The V groove supplies friction on two sides of the belt making it almost none slipping.

Note: If you would have checked Nigel Lawtons page on pulleys you would have caught an error I made in range size of the pulleys he offers. The largest one he sells is a 9mm root diameter pulley, not a 12mm. I mistakenly looked at the belt diameter. The largest one being 12mm dia.



Now tell me it's not going to work. Try something before you theorize that's not going to work. I did and it works just fine.

The British use belt drives on their 4mm scale models. http://www.clag.org.uk/axle-hung.html

Bernd