# New Member



## chiliviking (Dec 30, 2007)

I just found this board last week and think it's great. I lurked for a long time on the HSM board and recognize several of the folks on this board. I just finished my Ajax kit from Tiny Power. For my next project I have ordered the 1890's lathe castings from the Engine Shop for the 1/12 scale engine lathe. I would be interested to know if anyone has built this unit and has any tips for me. Thanks in advance for any info I may receive. I am looking forward to participation on this board.


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## rake60 (Dec 30, 2007)

Welcome to HMEM chiliviking

Very nice work!

Rick


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## mklotz (Dec 30, 2007)

Are you thinking of the 1/12 scale lathe from PMR? (I'm not familiar with a model lathe from "Engine Shop".)







If this is what you have in mind, I've (obviously) built it and perhaps can help you (although it's pretty straightforward). Feel free to ask.

Oh, and welcome to the forum.


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## chiliviking (Dec 30, 2007)

mklotz..

I actually bought the lathe kit on ebay but first learned of it from the Engine Shop website. It appears to be the same lathe as you have so finely constructed. I will most likely have questions as the construction goes on and would be most appreciative of advice along the way. Did you find the directions with the kit to be adequate or is your success atributed to great skill and experience on your part?


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## mklotz (Dec 30, 2007)

Much as I'd like to say it's due solely to my legendary skills, I'll forego such an exercise in back-patting and tell you that the plans that come with the kit are exellent - as are PMR plans in general.

Complete as the plans are though, they don't offer a great deal in the way of help on fabrication procedures so I'll offer some suggestions to get you started.

Milling the lathe bed, with four prismatic ways, requires great patience and preparation.
I laid out a detailed, step-by-step cutting schedule first and then proofed those plans on a piece of scrap aluminum. This test part then later became a fixture for holding the headstock and tailstock for drilling and boring. I made a similar test piece for testing the procedure for cutting the female V-ways in the HS and TS to ensure that, when finished , they would fit nicely on the ways. Buy a V-tipped endmill to mill the way prisms - don't attempt to tilt the lathe bed. (I attached the bed casting to a sturdy backbone for the duration of the work done on it. This gave the MM vise something to grip and prevented milling forces from bending the casting during machinining.)

The 1/32" wide, 4+ inch long slot in the 1/8" OD power feed shaft can't be cut with an endmill (unless you have far better equipment and skills than I have). Make a jig to hold the rod rigidly and use a slitting saw.

Throw away the supplied castings for the cone pulleys. It's far easier to make these from bar stock so you have something to hold onto in the lathe. You'll waste a lot of time trying to come up with a jig to hold the supplied castings and they won't be as accurate as ones turned from bar stock.

A collet setup is essential for holding the gear stock to make the myriad gears.

I made the 3 ball handle for the crossfeed by using one of my computer programs to generate an incremental cutting schedule. This technique works well although, today, with more practice behind me, I would probably do it by hand using a graver - similar to turning on a wood lathe.

The oil cups (for the HS main bearings) that you see on my model are not called out in the plans. I think that they add a nice touch of realism and encourage you to consider making some for your model.

By all means take the time to make the working 4-jaw for the model using the included plans. I did and it's a real attention getter when I exhibit the model.


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## chiliviking (Jan 3, 2008)

I received my kit and it indeed is a PM research kit. It is smaller in scale than I imagined and will present a challenge to say the least. I have a nicely tooled shop for a hobbyist but am going to have to buy some smaller end mills and such to work on this small of scale!


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## mklotz (Jan 3, 2008)

Chili,

No question you'll need small tools to complete that lathe. If you look at my picture above, that coin is a Sacagewea dollar - about the size of a quarter.

MSC has sets of miniature end mills. This is the one I have

http://www1.mscdirect.com/CGI/NNSRIT?PMPXNO=1691878&PMT4NO=35206214

A high-speed spindle is essential for using such small endmills. I have a Unimat and run it at max speed and that's still low for the recommended cutting speed for such tiny endmills. 

You'll also need some 0-80 and 1-72 taps and dies as well as the big stuff like 2-56.
And, as I said above, get a 90 degree point drill-mill to cut the ways on the bed.

Finishing it is a fiddly job bound to test your patience. However, when done, it's a great display piece and a sure attention getter at club meetings and exhibitions.


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## S_J_H (Jan 15, 2008)

I just purchased this kit and it is going to be my next project. 

 mklotz, Thanks for all the tips and your finished example looks great!

Steve


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