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keitaro

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just a question when you have a train with a metal body around the motor what tool etc do you use to make more room in the body?

 

this is not for dcc but i need to take 1m off to fit a motor into my kiha 130 hidaka line model.

 

the original motor works but i wanted to upgrade to a fly wheel motor as a custom job for it.

 

As it stands I need to clear out 1 mm max to get it through the body to get it running it only just by a hair doesn't slide through the hole. I considered a drill but was affraid it may make damage to the body.

 

 

i figue 1 mm to make sure it's got a bit of space incase the train moves the motor on slopes and causes rubbing.

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There are a lot of factors that play a critical roll in a successful job verses a catastrophe. The size of your end mill, its flute and the speed in which it cuts is the beginning . Next is the precision in which you can make the passes (depth of cut in), the speed of the end mills rotation and finally the speed of the pass it self.

 

Not sure if you need to ream a hole or mill the body but in any case it takes precision to work with N-scale mods. It can be done by hand but you risk compromising the integrity of the body or unit as a whole. Being that you are working on a metal body it might not be that much of a problem but you never know.

 

This image is an end mill which scrapes/cuts the surface. 

endmill2fl.gif

 

The drill bit digs a hole. Because of the digging action it will twist into the metal.

drill-bit.gif

 

 

Although these examples are plastic it holds true based on the effects of size and thickness of the material.

This is my first hatchet job that seem to compromise the body a bit. I shaved the roof but the sides were effected where the body would not snap on any longer. The center bowed outward.  

[smg id=797]

 

 

After learning from the first job I used a mill and removed as little material as possible to maintain structural integrity. 

 

[smg id=946] [smg id=950]

 

[smg id=847] [smg id=849]

 

 

I always try to put things into perspective. I will not let a $3 bit destroy a $100 train but it cost on the other side too a good end mill will cost you $20 to $40.

 

So, you are right in thinking to mill it, just make sure that the unit is secured in a vise and will not move. If it move then consider it gone because you will not be able to respond in time.

 

Inobu

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CaptOblivious

Ghan:

 

I use a Dremel with a steel high-speed cutter bit for frame milling. Not precise, but gets the job done, and easy enough to make neat and tidy with a bit of elbow grease. Cheap, and gets the job done. I'm still trying to find the right tool for plastic, however.

 

Inobu: O/T, but is that a Digitrax decoder in your EF210? How in the world did you get away with removing so little material? I've just done an EF210 install for a fellow forum member, and found I had to remove far more than that to get the shell to fit.

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Ghan:

 

I use a Dremel with a steel high-speed cutter bit for frame milling. Not precise, but gets the job done, and easy enough to make neat and tidy with a bit of elbow grease. Cheap, and gets the job done. I'm still trying to find the right tool for plastic, however.

 

Inobu: O/T, but is that a Digitrax decoder in your EF210? How in the world did you get away with removing so little material? I've just done an EF210 install for a fellow forum member, and found I had to remove far more than that to get the shell to fit.

 

That's what I meant about milling. With the mill you can mill to .05 mm and remove only what you need. Here is the trick.

 

Get a dry marker and color all the high points. When you place the cab on it will transfer and mark the cab roof. Mill down those area until there is no transfer. The problem with the dremel is your breathing, heart rate everything jacks with you (LOL).

 

Some of the cuts are for air pockets for heat displacement.

 

One reason I can't job my work, the time/cost factor. It takes a lot of time which cost more money than the average guy wants to pay.

 

Inobu   

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I got a harbor freight Mini Mill

 

image_1125.jpg

 

This is a little 2" vice it is heavy duty and won't move. 

480.1590.jpg

 

I know you will look at the cost and shake your head but here's how I see things. I buy tangible things. I avoid restaurants as much as she allows me to. This mill is 6 trips to Claim Jumper's and 5 movie tickets. I bought this 5 years ago. I had this from my other hobbies. I buy things that has a wide span of uses which allows me to get my moneys worth. I will have the mill until the end of time. It cost me $400 but I use it for a lot of other things.

 

It's better to give up 4 trains that sit on the self for 1 mill that can cut precision stuff (if that's what you like to do).

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hmm thanks all looks like i might be looking at that dremel.

 

although it'll have to wait as it's not so cheap and a train would be much better investment  :grin

 

might ask my mate he has a wealth of tools and machinery perhaps he has one already.

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keitaro

 

Did not mean to go off on a tangent but, here is a cheaper alternative

 

With the dremel press you can mount it and Just barely pull the handle down and touch it and move the vice a little by hand and touch it again until you get the cut.

 

dremel%20drill%20press.jpg

 

480.1590.jpg

 

I would get these two. Make a guide that bolts to the drill press plate and just move the vise across the jig by hand. Less than $100 dollars if you already have a dremel.

 

Inobu

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lol nah I don't have a drill press either.

 

I have a drill, saw and a hammer hahaha. i.e. no tools.

 

Main reason is we rent and have no room for tools at this time as are in a town house.

 

I have a ton of reward points at work when i get a house i have plans to convert them into $600 or more maybe worth of giftcards for bunnings to go tool crazy.

 

and perhaps buy supplies for my next layout, to make the table.

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Most drills aren't designed for a lot of lateral stress.  Using an X-Y table with a dremel would be fine, and using it with a drill press to mill plastic is unlikely to do harm, but I'd be reluctant to mill a locomotive weight with an ordinary drill press.  Over time, that's likely to damage the bearings.

 

I have used a hand-held drill to mill cut-outs in sheet metal, with no obvious ill effect (it's a crude technique, but worked for what I needed).  But I've only done that a couple of times, not a lot.

 

This whole thread has me thinking I want a milling machine instead of the drill press I'd been planning to buy, but the good ones (like Inobu's) are running around US$600 and up now, without the hardware you have to add (bits, vices), so that's a pretty major investment for something I'd probably use a half-dozen times a year.

 

There's a nice mini-mill comparision page I found. I think this only compares those that are based on a single design made in China, but it's apparently the most common one.  I know it omits some models out there.

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I bought a Proxxon micro mill for ~400. It's smaller than the Chinese mini-mills, but supposedly better quality.

 

Of course, I haven't had a chance to set it up yet. That'll be sometime next month....

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Most drills aren't designed for a lot of lateral stress.  Using an X-Y table with a dremel would be fine, and using it with a drill press to mill plastic is unlikely to do harm, but I'd be reluctant to mill a locomotive weight with an ordinary drill press.  Over time, that's likely to damage the bearings.

 

I have used a hand-held drill to mill cut-outs in sheet metal, with no obvious ill effect (it's a crude technique, but worked for what I needed).  But I've only done that a couple of times, not a lot.

 

This whole thread has me thinking I want a milling machine instead of the drill press I'd been planning to buy, but the good ones (like Inobu's) are running around US$600 and up now, without the hardware you have to add (bits, vices), so that's a pretty major investment for something I'd probably use a half-dozen times a year.

 

There's a nice mini-mill comparision page I found. I think this only compares those that are based on a single design made in China, but it's apparently the most common one.  I know it omits some models out there.

 

Ken,

 

ive done milling on small to huge milling machines and also on a lot of drill presses of many sizes in a pinch on soft metals, plastics, and wood and never had a problem with the bearings. most drill presses have pretty good shank bearings in a few places. granted not as beefie as you would find on a mill shank, but fine for lightweight stuff.

 

i always do small passes and dont use huge cutters. also never do it for hard metals. its fine if you do a little here and there. if you are going to get into doing a lot of milling then yes a small mill is great, but usually start in the $400-500 range and most folks just want to cut some simple things here and there. the little xy table helps with this (although z is a pain on a drill press). i have used a fence on a drill press and hand pushed it thru when i didnt have a xy table.

 

hand drills are definitely not a beefy in the shank and bearings as they are made to be light weight, but even those take a lot of side toque when you use them and they do pretty well!

 

cheers

 

jeff

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ha Unimats are coming back! the company is sort of reinvigorated and they are starting to be distributed to the us as well.

 

i have the old basic one someone gave me as they werent use it. that one is pretty useless for anything other than a kid playing around some with soft woods. the next one up starts to have some milling potential. the classic version 1 starts to have milling potential but is not cheap in the us...

 

jeff

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I bought a Proxxon micro mill for ~400. It's smaller than the Chinese mini-mills, but supposedly better quality.

 

Of course, I haven't had a chance to set it up yet. That'll be sometime next month....

 

the proxxon looks like a great simple tiny mill for doing micro stuff and soft materials. its not really a full duty milling machine, but then you have to move up to one of the heavier duty small mills like the mircolux that micromark sells for like $429. ive been tempted by this one a few times, but still get by fine now with the little xy table on the mini and full size drill press for now...

 

it does really depend on how precise you need and how much power/strength. they start to get big quick and can take up a lot of bench space in the shop! like inobu said as well then you get into buying nicer cutters as well to do more precision work with harder materials and that can start adding up fast!

 

i do love the proxxon high speed rotary tool, best i have ever had. their little drill press for it is also a nice piece of gear.

 

cheers

 

jeff

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I bought a Proxxon micro mill for ~400. It's smaller than the Chinese mini-mills, but supposedly better quality.

 

Of course, I haven't had a chance to set it up yet. That'll be sometime next month....

 

the proxxon looks like a great simple tiny mill for doing micro stuff and soft materials.

I'm mostly planning on using it with plastics, etc for my n-scale stuff. I've got parts to convert it to CNC, but that's a project for sometime in the future...

 

its not really a full duty milling machine, but then you have to move up to one of the heavier duty small mills like the mircolux that micromark sells for like $429. ive been tempted by this one a few times, but still get by fine now with the little xy table on the mini and full size drill press for now...

jeff

 

The Proxxon seems to be considered a "jewelry" mill. I wanted one of the bigger ones, but I'm in Canada, with no local dealers. I was looking at close to $1000 by the time I got one of those things up here.

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the proxon should be great for small plastics milling like that. only drawback is that they are only small rotary tool size bits. cnc can be fun! also does not take up the whole workbench and wont give you a hernia trying to move it!

 

cheers

 

jeff

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Jeff brings up a few points that is worth discussing "small rotary tool size bits". This is important in that the cutting ability is not only based on the torque of the mill but in the size of the bit.

 

Milling is the ripping or chipping of material in a uniform manner. Even steel is chipped away although it appears like a cut. The power of the mill and the size and type of bit dictates what the mill can cut. Like the size of a hammer and chisel. It is important for you to buy a mill based on your usage and set it up to support that need.

 

The first mill posted can cut plastic to light metals. I not only machined my train stuff but I also machined the ejection port on a Glock. It required a cobalt bit but I was able to do it. There are principle behind your setup that you must adhere to in order to successfully complete your task. The Proxxon is good for plastics, woods and some soft metals but due to the bit size you will have to make a number of passes for hard material. It can only nibble away at the hard stuff because of its light power and small bit size. It can take forever to cut hard metals or thick material.

 

Remember I mentioned usage and setup.

 

When working with plastics within N Scale you are still looking at another factor "Size". You have to think and visualize in scale. The smaller Proxxon can better work with plastics but it too can create problems that you will not realize until it is too late.

 

A 1/8" or 3.18 mm end mill is equal to a 20" or 50 cm bit in real life. So just imagine cutting a 2" or 5 cm thick piece is steel with a 20" or 50 cm bit. It will tear that steel plate to bits. Now reduce the bit to 1/32 and it equivalent 5" or 13 cm which is better.

 

Remember you are using a real cutter in an N-Scale world so set it up relative to the environment.

 

Inobu

 

   

 

   

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so i got out my needle files last nihgt and started. 2 hours later i realised this is going to be a looooong project.

 

 

 

Anyway after 2 hrs i got bored and for shits and giggles wired it up with the motor sitting on top of body as it doesn't fit and and probably won't for a long time ...

 

I then placed on some custom axels to the trucks and tested it. given my 2 min slap up axels the didn't grip the grooves right it ran really fast.

 

For the axels I got a needle from sewing kit cut it down to size and bent it to grip in the grooves. x2 on both sides.

 

This thing runs fater than a shinkansen. since the motor is from the newer de10 it runs very fast..... maybe too fast.

 

Might start up a custom train racing group.  :laugh:

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