G Gauge/Scale Japanese Skinkansen 500 Bullet Train ??

[Toy Maker]

 

Right now, I am laying out the "engine" or end cars, whatever you want to call it. I am working up a 3D wire-frame drawing in AutoCAD, and will be sending it out to another guy that does amazing 3D model surfacing work in Solidworks.

I never got into surfacing, and this thing has a pretty complicated surface mesh.

Once he is done, I am going to be sending the 3D nose model off to a friend in California, who will be running me 3D machined aluminum billet noses for the train. Those will be fitted to the extrusion and welded together.

Once it's welded and sanded, the seam should be invisible. 

I got great news back from my source in China last night... They are going to waive their usual 2000lb minimum and go ahead and run the smaller quantity I was hoping for.

 Most of the really "hard parts" are getting ironed out, and it seems like this is going to be pretty do-able after all. I know I am going to be running into little obstacles all the time, but the really big issues

(body and nose) are working themselves out it looks like. 

Next will come the trucks, and powering them. So far, I really like what KMT did on the O-gauge version. I am planning on copying that design. But I need to find a way to synchronize 8 electric motors, when 4 will be at one end, and the other 4 will be 25 feet away in a different car. What are the chances that 8 of the same electric motor are all going to be close enough in RPM to not have to synchronize them ??  Anyone know of a small electric motor that you can manually adjust its RPM?? That might be a good way to go.

If you sync all 8 before putting them in, than they should all continue to run at the same speed. Maybe check them every so often. Put a small adjustable pot on each motor...  I dono.

Here's a link to a big verson of the same image http://www.radicalrouting.com/500/3Dmodel1.jpg 

 

[IRB Souther Engineer]

Toy Maker

 

  
But I need to find a way to synchronize 8 electric motors, when 4 will be at one end, and the other 4 will be 25 feet away in a different car. What are the chances that 8 of the same electric motor are all going to be close enough in RPM to not have to synchronize them ?? 

 

 

I don't think you need to worry so much about that (if you use an R/C system). I think you need to worry about the Amperage that 8 motors pulling a pretty heavy load would draw...

 

If you did R/C one solution that immediately comes to my mind is add one receiver in one powered car and a second receiver in the other powered car, then add the two receivers as a consist (MU them) in your R/C system so they operate in sync. 

 

Take a look at this http://www.aristocraft.com/techinfo/revolution/REVOLUTION_TE_manual_Rev_A_0409.pdf (go to page 27). Even if you didn't use this exact R/C system you will get the idea of what I'm suggesting.

 

For motors you may want to look at something like this: http://www.nwsl.com/motors-power-drives/the-super-magic-carpet

[cabbage]

Don't worry about the sychronization of the motors. The weight of the loco on the track will force all the motors to revolve at the same rate. What you will have to worry about is the power supply and the power specifications for your bogies. There are really only two options. EITHER you take power from the rails OR you have on board batteries. There are pluses and minuses on both sides. Before you decide I would suggest that you try and work out some masses of the loco and the complete train. If you go for on board batteries then the best place for them is in the power cars at either end. You then have the problem of connecting right through the two ends... If you go for track power then you have pick up problems -which might not be that high given the number of potential wheels that are on the track! I am going to point you in the direction of the main motor supplier for the models that I build. http://www.mfacomodrills.com/motors/motors.html A G3 loco normally uses 360 to 385 rated motor per axle. I would stick to MOD 1 gears as this makes the maths easier and the coarser tooth makes it easier to keep clean. regards ralph

[Toy Maker]

 Well, I went ahead and bought a few different brushless motors last night off eBay. These motors might work just perfectly for what I am thinking about doing.
Most of these motors COME APART...  Which means I can make custom drive shafts for them. They are also small enough to place BETWEEN the wheels.
Direct drive on as many axles as I want. I am thinking all 4 axles on 2 cars (8 motors) should be plenty of power. These motors can be driven via the track voltage, or they will be able to be run off battery packs.

They will be in this week or next, than I can do some real testing on them, and see which ones will work best for this application.

[Toy Maker]

Back from vacation !!! 
Sorry it's been a while since I posted, had a ton of personal stuff going on... (still do)
but at least now, I have my head above water.

Just wanted to update everyone on the Bullet train.

I finished the drawings, and sent them off to the extruder.

Here's what I got back as a "sample"

 

 

 

Coming along, slowly but surely !!!

[cabbage]

That is lovely! You will in effect have a monocoque construction for your carriages and with the extruder die -make them like a string of sausages... Fettling out all the windows etc is going to take time -but already you can see the thing as a whole. (Unfortunately my current loco is held in two ice cream tubs.) This when finished is not going to be a model -more a work of art(!)

regards

ralph

[Toy Maker]

I thinned out the material where the windows go. The entire profile is 2mm thick, except around the windows, there it's only 1mm thick. I made little micro notches top and bottom of the window, that I can just snap in a strip of .005 - .010 thick acetate behind the metal.

The material thickness will be so thin, it should look really clean when the windows are put in.

 

As for cutting everything...   I have (2) CnC router tables, each is 6' x 12'.

The plan so far is to make a master jig, that will hold the 36" long car in place, and will have removable window pattern inserts for each of the different car window/door spacings.

Since there are 12 different car layouts, it will be easier this way, than to set up everything in the machine. Building custom jigs for the machine is fine if you are going to run 50-100 of the same thing, but running 16 cars, where 12 are different, isn't worth the setup time.

I will probably be cutting the windows with a trim router. I have tons of cutting tools.

Building the jig will be the tough part, but once it's setup, doing the actual cutting will go really fast. I'd expect I could do each car in 10-15 minutes at worst.

[Toy Maker]

Sorry for the long time gaps between posts, but this is a pretty slow moving project, since so much of the project has to be shipped in.

The full batch of aluminum extrusion pieces are complete, and on their way to the US as I type. The motors have been bought and paid for, and are on their way.

I am super excited to see all these parts coming in at the same time.

 

As for the number of motors...  I have gotten some amazing advice on the forums from a few people.

One of which is a guy that is a servo motor engineer, who spent a number of hours helping me calculate the (weight / torque / traction / RPM) ratios of this train.

Each car is going to be in the neighborhood of 5 pounds for a total train weight of about  75-100 pounds

The big problem, was getting the train up to "full scale speed" within a reasonable amount of time.

The train will run on fewer motors, but you will start to run into traction, and ramp-up speed problems.  With this many motors, the train will get up to speed faster, and will little to no slippage.

 

I have also met a new local friend here is Fort Myer, one of my daughters frineds father.. and we are talking about running the nose cones from solid blocks of aluminum again.
He just moved to Florida, and is looking for somewhere to setup his 4-axes CnC milling machine :) and it's looking like my shop might be the perfect place for it.
So very shortly, I may be able to 3D mill all the needed parts IN HOUSE !!! GOD that would be NICE !!! This guy is a Soldworks master, and is willing to teach me everything I'd need to know.

So, things are moving forward, and looking GREAT. I can't wait for parts to start showing up...

I'll post some more as soon as I have something for you guys.
Hope everyone's hollidays were great !!!!

James

[Toy Maker]

Well, all the extrusion profiles came in today. Guess it's about time to start doing some REAL work

soon.

[Toy Maker]

 

Well this project is going "Slow but Sure"

I have been having to learn a whole new world of 3D design. 

These complex compound surfaces are very tricky to redesign

The hard part is almost over, and the nose design work is almost finished.

I opted to go back to AutoCAD for the nose cone. The new 2013 version now has ALLOT of the same features that SolidWorks has, but it much more flexible in the drawing department.

The hard part is over. Now I just have to do the bottom skirt portion on the nose. 

 

My son also just bought an awesome new toy..... 

Should make making all these custom parts MUCH faster and easier.

watch?v=Sx2AvY2Qsa8

 

 

[Toy Maker]

MAJOR UPDATE !!!!!!!!!!!!!! PLEASE.... Follow and LIKE this project on Facebook from now on.
https://www.facebook.com/Shinkansen500 

It's a little too much for me to keep posting in 3-4 different places/forums trying to keep everyone updated. 
My son has set up a Facebook Page: https://www.facebook.com/Shinkansen500 
This is where he and I will be uploading photos, videos, and new info. It's much easier, and pretty much automatic to upload to FB from any of our phones, and cameras now. 




This project has been going pretty slow over the last year. Been slammed with work at the shop, and haven't had much time to work on hobbies. 

This week, my son took on a few parts, and I thought I'd update everyone. 

He worked on a jig that took 2 days to build, that allows us to lock the cars in place, and machine the windows, doors, and any other openings that need to be cut from the sides. 
He also machined a few end-caps for the cars. We needed to do a few tests to see which would be the tightest fitting inserts the help keep the extrusion to the perfect shape for the outer end-caps to fit perfectly. 

Please go to the FP page to see the new parts

[Toy Maker]