Interested in 1/150 6.5mm or 7.1mm gauge?

[Ken Ford]

There has been some discussion of N scale modeling on 6.5mm gauge track in other threads. I know this is specialized, but I'm curious if others here are interested and care to share their experiences and knowledge.

 

I've ordered a loop of Micro-Trains Z scale track to use for experimentation with my Tomix Etsumihokusen Kiha120. I've been planning a simple small diorama / layout on which to run it, and it would make a nice self-limiting project since only the two cars would need to be converted. Plus, Tomix power trucks are available as replacement parts if everything goes pear shaped with the regauging.

 

One thing I'm finding is that most 6.5mm conversions are on Kato mechanisms, it seems they are easier to convert than Tomix. I'm still wiling to give the Kiha120 a try, though.

 

One inspirational webpage I found through posts here is http://www.vivant.jp/taichi.htm - that plus sites linked from there have been very useful.

 

Anybody else warped enough to give 1/150 6.5mm a try? Please chime in!

Edited February 26, 2015 by Ken Ford

[HantuBlauLOL]

Tomix mechs seems to be very hard to convert.. I think that's why that web's owner used Kato chassis inside a tomix shell.

[E6系]

Oh ... I had lost this link.  Thank you.

[Kamome442]

Hello Ken, 

I just thought would introduce myself, I am also attempting to convert some N scale trains. I have decided to convert them to 7.1mm and run them on homemade track (I like to make things difficult for myself!) from a 3D printed master which is used to create molds. I have to say converting Kato trains is actually pretty easy and only takes me about 3-5 minutes to convert a carrage. I also have a couple of tomix trains waiting to be converted. I have 3D printed a jig to convert the wheels for trailer cars however I have not yet tested on Tomix stock. I have attached a picture to show the difference between 7.1mm and 9mm track. If you are interested I can post some pictures of my jig.

Joe

[katoftw]

I would like to see it.  You make it sound easy if it only takes 3-5 minute per car to convert.  Thanks.

[Ken Ford]

Joe, you have my respect - 7.1mm is serious modeling! Please, post more photos - the one above perfectly illustrates what I like about gauge corrected models.

[cteno4]

Joe,

 

Great work! Really looks nice on the 7.1 rail!

 

Jeff

[E6系]

Hello Mr kamome442,

 

Your conversion looks amazing.  For 3-5 minutes work I would love to see a how-to video :D

[SantaFe1970]

Boy, the stance of the train is so much better on proper scale width rails. Like everyone else says, brilliant work.

 

Now, I'm aware that running 1:150 trains on z-gauge would not be as near-perfect as the 7.1mm above, but I bet there would be a market for relatively plug-and-play z-gauge conversion kits. Do any such kits exist?

[Ken Ford]

I've found a store that offers converted Kato equipment, and I suspect there are others.

[Kamome442]

Thank you for your kind words. I have to say it was never my intention to take things this far, I was just curious if it could be done and I happened to have a spare carriage. Once I saw the results I could not leave it alone! I am a little tied up with work for the next two weeks however I will try to make a short video in a couple of weeks time. For now here are a couple of pictures. First the original jig (since updated with 4 positions to convert a bogie in one go) from left to right: the nuts and bolts that hold it altogether, a plate to hold the wheels (axles go through the holes and the wheel face rests on the plate), a frame for the plate to drop into, and a back plate to hold the wheels in place. When the wheels are in the jig the little plate stand proud of the frame by 0.95mm I then pop it in a vice (one side touching the moving plate the other touching the bottom of the bolts) and squeeze it until the plate is flush with the frame. Then I just need to cut 1.9mm from the plastic axle. Next this is the process I use to create the track, a 3D printed mould, silicone rubber negative, a completed cast (resin) and the finished track with rail glued in place. Finally a picture of the a train on the finished track.

 

I will post a few pictures of my early tests to show the progression to this stage over the next couple of days, I would like to add I can only convert in 3-5 minutes with 4 position jig, the first few conversions were done with a hammer and some calipers and took around 10 minutes. Motorised bogies are still quite time consuming as you need to file down parts of the frame. As I am always looking for a simple (lazy) solution I am going to try using a dremel to sand down the plastic (I have ordered some spare bogies to practice on!). 

 

I have to say I have not had the courage to work on Tomix wheels yet, I took apart a motorised bogie and then put back together straight away once I saw it's complexity. I will have to face it soon and if I can help you I will once I know what I am going to do.

 

Joe

 

[HantuBlauLOL]

It seems that we need to cut the wheel holder down and make a new one with 6.5mm width on Tomix trucks for 7.1mm gauge.. On Katos we could just cut it down without making a replacement for it.

[Martijn Meerts]

I never minded the 9mm track, but seeing them side by side, the 9mm one looks silly ;)

[kvp]

Most Tomix wheels are very simple. They are made out of two halfs, each wheel turned in one piece together with a half axle. The middle plastic spacer holds them together and isolates them. The power pickup (if there is any) is in the bogie sideframes, creating a metal journal box. They can be regauged by removing the wheels from the plastic, cutting off a few bits from the plastic and the metal axle, then reassembling it. However the sideframes have to be resized too, both the plastic and the metal parts. (actually the plastic is not a real problem, since the metal parts will hold the wheels in place) Resizing a power bogie could be a problem, since the gears tend to fill the space available. Imho it might be easier to just replace the inner frame with a thinner one. The good thing about this design is that it's very hard to get a wheel out of gauge, since they can phyisically not go in and the frames won't let them come out of alignement. Also on the pickup equipped cars the wheels roll in a metal journal, which results in very low rolling resistence and good pickup, since the whole weight of the cars are on the contact surfaces.

 

ps: I have to admit it, that the correctly sized track makes the trains look much better when viewed from the front.

[Kamome442]

Hello kvp you are absolutely correct about Tomix wheels I was being a bit of a naysayer in my last post. The trailer wheels are very simple indeed having a single piece axle and to convert them should in theory be just a case of taking them off the train and putting them straight in the jig, adjusting one side before turning them over and adjusting the other. I say in theory as I have not actually tried it yet. My main concern is that the force of moving the wheel might damage the end of the axle. The holes in the back plate is tapered to hopefully spread the load applied to the tip of the axle. 

 

The part that freaked me out was the motor car having a metal collar around the axle that needs to be cut away, I have never converted any trains before now and have little experience cutting or grinding metal. I really just need to give it a go and see what happens, I know it is possible as it has already been done the there is an utterly amazing project on this forum converting trains to 7mm called Nn3½ where it has been done. I will see if I can find the thread again and post a link. One advantage of my project is that I don't have to cut away as much of the frame as people converting to Z gauge track would have to do.

 

HantuBlaulOL you are quite right I could make a new plate to adjust each wheel by 1.25mm instead of 0.95mm, it would be a very simple adjustment. The jig was pretty expensive so might not be feasible for anyone converting one or two trains, I am happy to give it a go if anyone is interested.  

 

Finally the pictures I have taken are usually taken from above as the difference in gauge is most obvious, from the side or low angles the difference is less striking. What really stands out is when you have two or more tracks as the gap between each line is visibly wider and looks much closer to the prototype.

[gerryo]

Just to try to get this thread back on the original topic of 1/150 on 6.5 gauge track for a minute.

 

Ken.  I have a bunch of Z gauge stuff here that I have no need for and will probably throw out some day. some of the Marklin Flex track, probably a few pieces of 110mm Straits. and some of their adjustable track pieces.  There are also some curves, don't remember sizes right now, and some turnouts - both left and right.

 

I would have to check some of my boxes and drawers, but I have some here somewhere.

 

They will be going cheap.

 

gerryo

[gerryo]

Sorry.  I thought I might be of some help. 

 

I guess it's time for me to learn where help isn't wanted.

 

gerryo

[Ken Ford]

Just to try to get this thread back on the original topic of 1/150 on 6.5 gauge track for a minute.

 

Ken.  I have a bunch of Z gauge stuff here that I have no need for and will probably throw out some day. some of the Marklin Flex track, probably a few pieces of 110mm Straits. and some of their adjustable track pieces.  There are also some curves, don't remember sizes right now, and some turnouts - both left and right.

 

I would have to check some of my boxes and drawers, but I have some here somewhere.

 

They will be going cheap.

 

gerryo

I'm sure if you post it here there will be interested people!

[HantuBlauLOL]

Kvp, isn't it Kato wheels? Tomix only used one axle for both wheels, and has no plastic spacer like Kato. But instead it uses a small rubber ring to isolate one of the wheel from the another one.

[kvp]

No, all of my stock has axle tip pickups and split wheels. This design is used even for the cheap tomytec sets, but without the pickups. A solid axle wouldn't work with the axle tip pickup system and also costs more to make.

[kvp]

For Z track i would suggest rokuhan. It's closer to tomix finetrack, has more radiuses, hidden turnout mechs and it's more reliable than the maerklin system from 1972.

[HantuBlauLOL]

You sure its not something like this?

 

 

Edit: My tip pickup equipped wheels used the same design as this. Except, the axle is splitted inside the another wheel, and that wheel has an integrated tip that isn't connected with the axle.

Edited February 26, 2015 by HantuBlauLOL

[Ken Ford]

For Z track i would suggest rokuhan. It's closer to tomix finetrack, has more radiuses, hidden turnout mechs and it's more reliable than the maerklin system from 1972.

 

That's what I'm planning to use if I convert any equipment - I picked up a loop of Micro-trains track to experiment, but the Rokuhan looks to be more versatile.

[kvp]

http://www.tomytec.co.jp/diocolle/lineup/tetsudou/images/unit/tt-04.jpg

As you can see, these have an integrated axle and a middle spacer. The solid axle type above is also common, for example marklin uses it for Z scale and i have similar ones in my high end sets. The common trick is that you need wheel integrated axle tips for axle tip pickup to work. It's possible to have completly isolated axles, but there is no point doing that. The side effect is the nice low rolling resistence. having non through axles also help keeping the wheels in gauge. Even Lego switched to the integrated tip version for non powered wheels to avoid out of gauge wheelsets on rolling stock. (motors still use through hole wheel mounting with inside bearings)

 

ps: Converting a side split version to a smaller gauge is possible by removing the metal axle, grinding it down and inserting it back into the plastic.

[Ken Ford]

Has anyone ever looked at the Tomytec TM-11R drive with an eye to suitability for narrowing?  I'm looking for a fairly simple first conversion project.