Miniature Machining

[MT Hopper]

It was a dark and cold December night 30 years ago. Chilled by the prarie howler and stung by the snow I welcomed the warmth of the Hobby shop as I stepped through the door into the dim light my breath sending up a plume of steam that would have done justice to a 2-10-0.Two of the regulars were hanging out at the bar, no I mean counter, eyeing up some of the latest locos. "Evenin' ", they said. I howdy'd back at them. The man behind the bar, no I mean counter, looked up and said,"good to see ya'." "I hear your shipping out back East and then over the pond." "Yup", I replied. "I got some of them uni mats in." The bar keep, no I mean Hobby shop person said. "I reckon you should get one now. You know next thing you'll do is meet some fraulien and then it'll be this 'n that an' you'll never have the money again to get one of these here machines." I allowed as how he was right an' so I bought me one.
Oh! Sorry, my children really must quit giving me so many novels for Christmas.
30 years later I have unwrapped the greased paper from the aforementioned Unimat. It's been in its paper and in the wooden box so long the paper is almost dry! Does anyone have any suggestions about;
1- how do I check the bearings on this thing?
2- what should I re grease the bearings with?
3- whats the best way for a mechanically inept one eyed old guy to learn how to use a miniature lathe (unimat)?
Any non rude suggestions are welcomed
Cheers from the Heart of the Continent
MT

 

[PWRR-2207]

Unimat resurrection

Here is a link to a site that sells replacement bearings and the manuals:

belts and accessories place order

(Your lathe may have sealed bearings and hopefully the site can help you figure that out.)

Personally, once you get her running, I would get some clear pine and try some of the different lathe tools (aka chisels) to see what they do.

Start with rounding a square piece and then see if you can shape into furniture legs or a lamp post. You can also smooth/shape the leg with a piece of sandpaper (no more than 100 grit or it tears striations into the pine).

Why clear pine? Cheap, easy to cut and shape plus knots in pine tend to explode/chip-out at high speed turning.

Safety - Couple tips in addition to the standard warnings:
- Goggles/Safety Glasses or a full face shield required (I would start with a full face shield until you figure out what is too fast for the different types of wood and/or metals.)
- Thick shirt but make sure the sleeves can be fastened down so they do not get caught in any rotating pieces/machinery.
- Do not apply too much pressure with the chisels. Be patient and let friction wear into the part. Getting 'the feel of it' is why I suggested starting with clear pine.
- If you do not have a tool rest attachment with the lathe, get one. They make results much more predictable, allow you to be creative without working hard at it and allow for more precise control of the cutting tool.

 

[sumpter250]

PWRR-2207,
Thanks for the link! He's only "down the road a piece" from me, and I could use new belts for my Unimat SL.
Pete

 

[60103]

MT: are you planning on doing wood or metal or both?
Did you use a lathe in shop at school? I only managed to get one project each in wood and metal. There might be evening classes at a local school (or do they still teach anything practical?).

 

[Kevinkrey]

I made a few projecects last year in school, hopefully more this year.

​

 

[sumpter250]

Did you use a lathe in shop at school?

Shop! that was a long time ago. The only lathe work I got to do in shop, was to turn a handle for the straight slot screwdriver I got to make...big screwdriver!
Pretty much I have taught myself how to use the Unimat. Mostly, I've set it up as a mill, to "make adjustments" to loco frames. When I get started on the On30 2-6-6-2, I'll be milling the frames, and possibly changing over to drill press mode for all the drilling that will need to be done. I would like to build this one with full working equalization.

 

[MT Hopper]

Thank You All for your help.
Like Sumpter I find MANY snows have passed since I did shops. I vaguely recall pressing a wood patterin into casting sand and then pouring a ladle of molten metal into the impression so I ended up with an ashtray to give my dad.
I suspect the constraint of time will see me go down the same road as Sumpter and I'll try to find a book so I can teach myself metal miniature machining.
Thanks PWRR-2207 for the helpful link.
I hope you all have a Happy New Year.
Cheers from the Heart of the Continent
MT

 

[Ray Marinaccio]

Pretty much I have taught myself how to use the Unimat.

Same here.
Once you read the manual and become familiar with your machine, experience will be your best teacher.

Measure twice then cut once.

I would like to build this one with full working equalization.

I've been thinking of building an equalized frame too.
I have to get some of these other projects off the work bench first.

 

[ChadYelland]

I'm a machinist by trade,, I'm not sure how to instruct on wood turning, but I'd say pick up a pocket book on wood turning or metal working, something like "Work holding in a Lathe" having chips fly at you is one thing, having the whole workpeice fly at you is another. learn how to mount and secure your material and the correct Rpm, and have fun.

 

[Jim Krause]

I was under the impression (maybe erronous) that the Unimat was capable of doing metal turning. Did it come with wood chisels and gouges? For metal turning, you will need different tool bits that clamp to a tool post on the lathe. Don't attempt to cut metal with a hand held tool.

 

[sumpter250]

Not erroneous, Jim, the Unimat came equipped to turn metal. You had to order the necessary parts to do wood turning.
Excellent point on not trying to turn metal parts with hand held tools! You caught me in a moment of "common knowledge syndrom"....I forget that there may be some here who have never operated a lathe, or seen a metal working lathe being operated.
When turning wood, the piece is usually at high rpm, and not only can it get loose, but a tool can be caught and sent flying. Care, patience, and protective gear are essential.

 

[MT Hopper]

Thanks to all for your help. The new/old lathe is a Unimat Model DB 200. It comes with metal turning tools. I also (at that time) bought the tool rest and wood turning chisels. I have an old book, Miniature Machining from MAP Model Aeronautical Press, that I apparently acquired along with the lathe.
Thanks again PWRR-2207 as the site you posted let me get some new belts, the old ones not having aged too well.
sumpter 250 are you moved yet to start the 2-6-6-2? Can't wait to see the results.

Cheers from the Heart of the Continent
MT

 

[PWRR-2207]

Metal turning

You are welcome

For metal, I would go over to a hardware store and get a piece of aluminum rod, at least 1/2" diameter.

Cut a piece with a hacksaw or metal bladed bandsaw about 3 inches long. Learn about the metal tools with that at low speeds and use gloves to pick up the shavings as they can be quite sharp. Start by pining both ends of the rod and then beveling an end ===<=.

If you have a 3 or 4 jaw chuck, try getting it aligned so it spins in-balance with just the one end held by the chuck. Once you figure that out, try shaping out a wheel from the inside. Good luck and I hope you have fun! :thumb:

 

[cedarcreekrr]

Being an industrial arts teacher I found once the students are shown how to use machinery they forget get 75% of what you told them and ask alot of questions anyway. Just remember If you get in trouble shut it off and try figuring out what went wrong and try again.

 

[sumpter250]

sumpter 250 are you moved yet to start the 2-6-6-2? Can't wait to see the results.

It's going to be a while. I'm currently working on a model of USS Carronade IFS-1, in 1/170 scale (Lindberg called the kit 1/160 scale), that will be drydocked on my Ntrak module. The 40mm twin mounts, represented in the kit by a "post and two barrels", have been replaced by two scratchbuilt mounts. There were close to 60 pieces that had to be made for each mount! I just got material for the liferaft cradles. Ships in drydock/ yard overhaul, usually have the liferafts removed for testing, and so that the cradles can be "preserved". I have to model them "empty".
I did find material for the boiler of the 2-6-6-2T, coal fired, with tender. Should look interesting.

 

[MT Hopper]

Hi sumpter 250.The ship sounds really interesting. Can you have her sitting in a drydock with one side of the dry dock cut away so she's visible? Makes me think of the Marine-Rail SIG I encountered. I've got my Walthers car float one eigth finished and then theres' the Float apron to be done. I don't know if it falls within your range sumpter but, while the New York Harbour Walthers car float is three track, would a Lake Superior car float necessarily have to be only two track to remain credible?
Cheers from the Heart of the Continent
MT

 

[MT Hopper]

PWRR-2207.
I got the aluminum rod and a brass rod. I also have both the three jaw and the four jaw chucks. The four jaw is a bit more challenging to centre up but I can see its definite potential in doing off centre turnings. I unpacked another wondorous cardboard box and inside the dried out paper is something the little previously white paper calls a dividing head. Darned if I can remeber why I bought that?! This is kind of like Industrial Archaeology. I vaguely recall buying some unimat odds 'n sods when ever my LHS buddy would recommend it but they mostly never got out of their boxes as life consisted then of moving to yer another posting. I even have a circular saw table for the unimat, which makes no sense since I already have a Dremel table saw. I think I'd better go open some more of those little boxes!
Cheers from the Heart of the Continent
MT

 

[MT Hopper]

sumpter 250.
You might be interested in the 2-6-6-2T build over on Yahoos Bachman On30 site. The chap used a Mantua 2-6-6-2T as the donor mechanisim and then added bits and pieces from the Forney,the Porter and the 2-6-0 and 2-8-0. It is a nice looking build.
Cheers from the Heart of the Continent
MT

 

[sumpter250]

Can you have her sitting in a drydock with one side of the dry dock cut away so she's visible?

Here's the Ntrak module, the drydock is in the far left corner.

 

[sumpter250]

This is a shot of the ship, in the drydock subassembly, before it was incorporated into the module.