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PM Research Milling Machine by Rik Thistle - FINISHED - late 1800s - 1:12 (est)


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Ron,

 

"How to run a Lathe" by Southbend Lathe company.

 

I've already built up a small library of general lathe and mill books, and specific ones such as 'Screwcutting in the lathe' - Martin Cleeve.

 

I see that Amazon.uk does offer the book you mention and it's only £6. My concern is that most older books I feel are written around more rigid, higher tolerance UK/European/USA built equipments rather than small 'Chinese, built down to a price' lathes. But I'll have a think about it 😉

 

Richard

 

Edit: Ron, I've now 'found' your book .... having a quick read-through now. And the lathe pictures therein remind me of a model lathe I built a few months ago!

Edited by Rik Thistle
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Many of these old books were written for bench-lathes, marginally bigger than my watchmakers lathe with 50 mm centre-height.

 

The watchmakers lathe probably isn't much more rigid than the SIEG, though manufactured to much higher standards. Here I am cutting the worm for the milling machine mentioned earlier.

image.png.92e618f5b227b5dc4bdadecc08f9128f.png

The cutting tool is actually a brazed carbide one as used on so-called Swiss automatic lathes. Their shaft is smaller (4 mm square) than the usual ones and hence better adapted to these small lathes.

Below I am making a lead-screw for a home-built micro-milling machine. I am not claiming any specific accuracy, but it works well enough for my modelling projects. In this case I used a home-ground HSS 5 mm square cutting tool:

image.png.442b2f04425cc2fe1c04c5c2a4fca0d5.png

First pass to check that the pitch is correct

image.png.cb393ca6ec03b780e7c1e9ed5a035f82.png

Last pass before chasing the thread with a die

 

Edited by wefalck

wefalck

 

panta rhei - Everything is in flux

 

 

M-et-M-72.jpg  Banner-AKHS-72.jpg  Banner-AAMM-72.jpg  ImagoOrbis-72.jpg
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Here I am cutting the worm for the milling machine mentioned earlier.

 

Thank you for the info and informative pictures. The results look very good. I think I need to go back and look at how I am grinding the single point cutting tool shape!

 

Richard

 

 

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Egilman,

 

Thanks. I think that ties in with what Wefalck has been advising.

 

...you set the top slide to 30 degrees...

 

The procedure I have been missing is to introduce the tool to the workpiece at 30 deg (using the top slide) so that the tool's leading edge (on it's right side) does most of the cutting.  I really can't remember if I was ever taught that back in the day...I may have but certainly don't recall it.

 

FeedWorn1.thumb.jpg.583ff8c0c77c4bb3f31b8945e0a7d1f5.jpg

 

I'm also wondering why the drawing asks for a chiselled end on the cutting tool. The mating teeth on the wheel are not flat bottomed...perhaps a rounded end on the tool would be less aggressive when cutting.

 

As I mentioned previously, I have ordered some proper EN1A mild steel so will use that together with your's and Wefalck's advice when the time comes. Meanwhile I am getting on with making handles etc.  I think I will tackle the Feed Worm issue once the project is finished, the decks are cleared and I have time to sit down and think it all out properly. I'll add an Edit if/when I am successful.

 

Richard

 

PS: I also just noticed that my Tailstock is about 0.25mm out in the horizontal plane - there is an adjustment for that on the tailstock, but it's a bit finicky to set-up correctly. I had adjusted it when I first got the lathe but over time it seems to have moved. Anyway, it would mean that my 2nd attempt, using the live centre for support, was probably causing the end of the workpiece to slightly wobble as it tried to straighten itself out.

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6 hours ago, Rik Thistle said:

The procedure I have been missing is to introduce the tool to the workpiece at 30 deg (using the top slide) so that the tool's leading edge (on it's right side) does most of the cutting.

Except in your case you want the cutter ground at 40 deg. thread profile set to cut from the left towards the right for left hand threads and the top slide set at 20 degrees... 

 

Ah, there is no engineering reason for the thread profile to be flat pointed, a round nose will work equally well, in fact engineering wise, probably better...

 

That will slightly increase the depth of cut needed to execute the profile though...

Edited by Egilman

Current Build: F-86F-30 Sabre by Egilman - Kinetic - 1/32nd scale

In the Garage: East Bound & Down, Building a Smokey & the Bandit Kenworth Rig in 1/25th scale

Completed: M8A1 HST  1930 Packard Boattail Speedster  M1A1 75mm Pack Howitzer  F-4J Phantom II Bell H-13's P-51B/C

Temporary Suspension: USS Gwin DD-433  F-104C Starfighter "Blue Jay Four" 1/32nd Scale

Terminated Build: F-104C Starfighter

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Quote:

"Relish Today, Ketchup Tomorrow"

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Egilman,

 

Strangely enough, when I got up this morning I was thinking about the issue and I wondered 'why 30 deg?' ....should it not be 20 deg. So that was going to be on my To-Investigate list today. But you have saved me the trouble, thanks 🙂

 

Richard

Edited by Rik Thistle
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Yes, of course, it has to be half the included angle of thread. Many (most) toothed wheels have a pressure angle of 20°, that's were the included angle of 40° comes from.

 

Incidentally, one can cut a worm-wheel with a tap as a cutter. There are various examples on the Internet for this. I have not done this myself, but I have made hardened concave knurling wheels in that way: https://www.maritima-et-mechanika.org/tools/attachments/attachments.html#Knurl. The matching worm would be exactly the thread of that tap.

wefalck

 

panta rhei - Everything is in flux

 

 

M-et-M-72.jpg  Banner-AKHS-72.jpg  Banner-AAMM-72.jpg  ImagoOrbis-72.jpg
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Hi all,

 

I'm getting close to the finish line. This post covers the last remaining parts ie handles and shelves.

1assy1a.thumb.jpg.f82ae7831d199d6486a8d17d42aeb25c.jpg

 

Firstly, the Crank handle for moving the Knee up and down. The same handle also moves the Saddle in and out.

2CrankLever1a.jpg.0ac0d2abf99e94c9e1e6febdbe502a06.jpg

 

The drawing calls for the Crank to be made out of one piece of 3/16" brass. I decided to fabricate it out of three parts.  I wasn't convinced I could bend the brass as depicted. I had some 1mm thick brass sheet that I did a test bend on and that bent fine - that convinced me to fabricate the Crank.

 

Below, the square hole was filed into the 3/16" brass stock. The end with the square hole was then cut off and cleaned up.

2CrankLever7a.thumb.jpg.96146e688cfaadd3bf78ba227942a877.jpg

 

Close up of the square hole.

2CrankLever7c.jpg.a807228cd799ec211949dbdfba94b427.jpg

 

The arm and circular boss.

2 Crank Lever 11a.jpg

 

 

After bending the arm of the Crank, it was soft soldered on to the square end using a hot air soldering station.

2CrankLever13.thumb.jpg.496de09b6582533ef8236465942c5a13.jpg

 

Next was cleaning up and fitting the two tool shelves.

3shelf1.thumb.jpg.19fe424c3573d928d0a2c6a558662476.jpg

 

As seen below, one shelf fits near the top of the mill and the other on the sloping side of the mill Stand. That latter shelf had it's mounting face slightly angled on my mill so that it would lie horizontal when fitted.

3shelf3.thumb.jpg.4a31f393f0399be2fca4d2589375004c.jpg

 

Both the Crank and the Feed Shaft require handles, as does the 'door'.

4assy1.jpg.d3c7d53a8e8709cd722465c62f423229.jpg

 

Below, the Door Knob and the Crank lying next to the mill.

4assy1a.thumb.jpg.790ae0f6293bf1971c8d9feab889b982.jpg

 

Lastly, the Bed Crank. Again, another square hole had to be filed...yup, I really need to get that broach made ;-).

5bedcrank1.thumb.jpg.eb694ed1b86521cdc110fd2af619dbdc.jpg

 

I had firstly turned the 1/8" dia end on the lathe. Then over to the mill to put the flats on the central section and drill the two holes.

5bedcrank3.thumb.jpg.8627952d05b9b3b8a768dd04be23dfae.jpg

 

Now ready to move back to the lathe for profiling the ball shaped sections.

5bedcrank11.thumb.jpg.ce690c64168eae011b46884f104bbf06.jpg

 

Finally, a couple of pics of the fully assembled mill (less driving belts, Pts 41)

6assy1.thumb.jpg.0ad63d52931af8895979d612459a0fd8.jpg

 

6assy3.thumb.jpg.436c9100ee45b64dff72c3dda29c94f6.jpg

 

The remaining work is to disassemble, fettle and clean, paint, make up the drive belts and reassemble. I'll post when that is done. I'll also have another go at making Pt 29, the Feed Worm and post progress.

 

All for now,

 

Richard

 

 

 

Edited by Rik Thistle
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Thanks Roger,

 

Yes, I learned new stuff doing this one. Still a little whiles to go before it is fully 'finished', but I see the light at the end of the tunnel.

 

Some parts are now in the paint shop, others in the 'fettling' shop. So the pressure is off 😉

 

Richard

 

 

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Hi all,

 

The parts are back from the paint shop and assembled.

 

Below. There was a good bit of masking areas off before spray painting. And after the masking was removed some touch up with a fine brush was required. Colour chosen was Black - this seems to be the dominant colour around the turn of the last century and matched the colour scheme of my Stuart Lathe.

1paint5.thumb.jpg.9ad4b94462ff7b17be8c4663151a090b.jpg

 

Also shown above are a couple of shafts that 1-72 UNC grub screws are meant to bite in to. I decided to add flats to all such areas.

 

Below, flats are being added to Pt 23, the Spindle Shaft.

1paint15.thumb.jpg.34e9f563f1aad6dd5b73178c02226cfc.jpg

 

Below. One of the last things to do was add the two Belts, Pts 41. The drawing calls for them to be cut to length, with a slight overlap, then the overlaps super-glued together. The best way I found to do this was away from the mill. I firstly coiled the complete length to introduce a curve to the belt, then cut to length and then I weighed down one end whilst a cocktail stick with a dab of super-glue was applied to that end. The other end was carefully introduced and held down with finger pressure, making sure I rolled my fingers to stop the belt becoming part of my hand.

1paint17.thumb.jpg.e32589933e76b627e989d30de837a1e8.jpg

 

Finally, three pics of the finished Milling Machine.  the wooden base is temporary till I find something a bit better- it did allow me to handle the mill more easily rather than getting fingerprints all over it.

2assy4.thumb.jpg.2af498a6fac9338c374d639e8f7ac417.jpg

 

Below, for scale, one material removal device sitting next to another.

2assy9.thumb.jpg.8123c46c4695b4b8e2c3678f4255958d.jpg

 

And the last pic shows the Mill about to meet it's workshop colleague, the Stuart Model Lathe.

2assy30.thumb.jpg.ed3223179be5e175fcc82bf776ca2a74.jpg

 

All the moving parts of the mill function as they are meant to - the handle at the front moves the knee up and down, same handle also moves the saddle. The belt drives work, and move the bed left and right.

 

I will have another go at screw cutting the Feed Worm, Pt 29, and add a post about how I got on.

 

Final thoughts are:

- An enjoyable project that I would recommend. The Aluminium parts meant the workshop was much cleaner than when machining the cast iron of the Stuart lathe. However, in some ways, the Stuart product seems a bit more 'real'.

- The drawing set was fine and adequate for the task. However, some of the dimensioning was a bit strange eg more than one datum on parts when really only one should be used.

- The scale is claimed to be 1:12 but I always felt the real mill would be approaching 6 feet tall - the model is 4" high.

- I thought I had lost one of the 1-72 grubs screws (...there are no spares in the kit) but I had somehow managed to installed two grubscrews in the same pulley fastening hole .... I found that out late in the day....and it explained why I could never properly tighten that pulley 😉

- I probably should have paid more attention to accurately making the Bed, Pt 4. It is quite important to follow the drawing dimensions 100%.

 

Thank you for all the Likes, Comments and very useful feedback I received. It really does help bring a Build to life and also helps motivate me and helps me learn.

 

I'm not sure what my next project will be....I have a long list to consider and some workshop improvements that need doing first.

 

All the best, and see you soon 🙂

 

Richard

 

Edited by Rik Thistle
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Nice looking machine.... Matches up with the lathe very well...

 

And btw, most job shop horizontal mills have a 4' spindle height, because most jobs are mounted by hand, the saddle height is set by the height a couple of workers could lift the work... So, at 1/12th scale, it is right on the money...

 

The sliding beam of a Cincinnati 2MH rises to upper chest height on me, and I'm 6' tall...

 

I'll be here when you choose the next one.... (psst, a radial arm would be perfect)

 

Beautiful work...

Edited by Egilman

Current Build: F-86F-30 Sabre by Egilman - Kinetic - 1/32nd scale

In the Garage: East Bound & Down, Building a Smokey & the Bandit Kenworth Rig in 1/25th scale

Completed: M8A1 HST  1930 Packard Boattail Speedster  M1A1 75mm Pack Howitzer  F-4J Phantom II Bell H-13's P-51B/C

Temporary Suspension: USS Gwin DD-433  F-104C Starfighter "Blue Jay Four" 1/32nd Scale

Terminated Build: F-104C Starfighter

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Quote:

"Relish Today, Ketchup Tomorrow"

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Egilman,

 

So, at 1/12th scale, it is right on the money.

 

OK, got it. Thanks.

 

a radial arm would be perfect

 

Interesting. I've mostly been looking at Polly Models' range of Anthony Mount models.... https://www.pollymodelengineering.co.uk/sections/stationary-engines/anthony-mount-models/index.asp  I'm limited to a 7" flywheel so quite a few of them are doable in my workshop.  But I'm a long way from making my mind up....all suggestions considered 😉

 

Richard

 

Edit: Yes, the Oil Field Pump has also caught my eye ... https://www.stuartmodels.com/product/oil-field-pump-unmachined/ ... it would be nice to see it running with my Stuart 10V, say.

Edited by Rik Thistle
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40 minutes ago, Rik Thistle said:

Egilman,

 

So, at 1/12th scale, it is right on the money.

 

OK, got it. Thanks.

 

a radial arm would be perfect

 

Interesting. I've mostly been looking at Polly Models' range of Anthony Mount models.... https://www.pollymodelengineering.co.uk/sections/stationary-engines/anthony-mount-models/index.asp  I'm limited to a 7" flywheel so quite a few of them are doable in my workshop.  But I'm a long way from making my mind up....all suggestions considered 😉

 

Richard

I ran a Clausing 60" radial arm back in the toolroom days... Impressive machine...

 

Those are some very nice engines, I particularly like the oil well field pump.... lots of moving parts, very rotational as well as linear motion, would be very impressive...

Current Build: F-86F-30 Sabre by Egilman - Kinetic - 1/32nd scale

In the Garage: East Bound & Down, Building a Smokey & the Bandit Kenworth Rig in 1/25th scale

Completed: M8A1 HST  1930 Packard Boattail Speedster  M1A1 75mm Pack Howitzer  F-4J Phantom II Bell H-13's P-51B/C

Temporary Suspension: USS Gwin DD-433  F-104C Starfighter "Blue Jay Four" 1/32nd Scale

Terminated Build: F-104C Starfighter

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Quote:

"Relish Today, Ketchup Tomorrow"

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I ran a Clausing 60" radial arm back in the toolroom days... Impressive machine...

 

Those Clausing machines look like very serious pieces of kit.

 

I did use a radial drill when I was undergoing training. I was always impressed how it could hold its accuracy even when the drill was out at the end of the arm.  Not sure I could build a model from scratch though.....it would require a lot of research and design, whereas I tend to target 3-6 month projects, at least for now.

 

But keep pushing...who knows 😉

 

Richard

 

 

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Thanks Wefalck.

 

Yes, there is quite a lot of 'bling' on it 🙂 

 

I think the model manufacturers do that deliberately to make the kit more attractive to potential buyers. It aslo makes the details stand out a bit more on a finished kit. For a display model it's OK, but for a 'real life' type model it would be unacceptable.

 

Richard

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brass oil-caps

 

Funny enough I was looking at that yesterday. I do have a couple of spare oil-caps from my previous models but I felt they were a bit too large to put on the Mill's main bearings. I may make smaller ones though.

 

Richard

 

 

 

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Amazing work!

Building: 1:64 HMS Revenge (Victory Models plans)

1:64 Cat Esther (17th Century Dutch Merchant Ships)
 

On the building slip: 1:72 French Ironclad Magenta (original shipyard plans)

 

On hold: 1:98 Mantua HMS Victory (kit bash), 1:96 Shipyard HMS Mercury

 

Favorite finished builds:  1:60 Sampang Good Fortune (Amati plans), 1:200 Orel Ironclad Solferino, 1:72 Schooner Hannah (Hahn plans), 1:72 Privateer Prince de Neufchatel (Chapelle plans), Model Shipways Sultana, Heller La Reale, Encore USS Olympia

 

Goal: Become better than I was yesterday

 

"The hardest part is deciding to try." - me

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Paul,

 

That is very kind of you, thanks.

 

It was an enjoyable build and probably just the right length of time for me.

 

I'm now trying to decide what to do next. Stuart's Oil Field Pump is a possibility   https://www.stuartmodels.com/product/oil-field-pump-unmachined/    along with some other ideas. However I feel I need something a bit different that will force me to learn new things whilst still being makeable on my mini-lathe and mini-mill. So, still thinking.... 😉

 

Richard

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Thanks Gary,

 

I had noticed your dioramas a while back...amazing work and you have an amazing skill set.  I'm off to read your latest, the Eastern rig dragger.

 

As for my next project, well it's in the post....another workshop item, partly encouraged by a poster here 😉  After that, I think I need to branch out a bit....maybe in to an area Elon wouldn't be too enamoured with.

 

Richard

 

 

 

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Thanks RetiredGuy,

 

I've got an f1.7 lens for my 4/3rds Panasonic camera which allows a shallow depth of field...it took a few tries to get the correct balance of sharpness of the Mill against putting the Lathe out of focus by the right amount. I also adjusted the distance between the Mill and Lathe to help with that effect. I too was happy with the end result 😉

 

Regards,

 

Richard

 

 

Edited by Rik Thistle
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