Quarry Hunslet

[philipy]

Steve's "Alice" type Hunslet inspired me to have a go at one. As he himself said, his is just basic and lacking a lot of detail and he was quite happy for me to do whatever I wanted to his basic stl's. ( thanks Steve).
So anyway, the stl's imported into Sketchup with no problems at all and I've spent the last couple of weeks adding rivets etc, and redrawing a few bits to get them the way I wanted. Once you start down this particular rabbit hole it is amaaaaazing just how many rivets and bolts and lumps and bits, there are!
Rather than an "Alice" I'm doing a "Britomart" type and since it won't be an exact model of an exact protoptype, Rule 1 applies! The final batch of Quarry Hunslets went to the Nantlle Vale quarries, two to Pen-yr-Orsedd Quarry and one to Dorothea Quarry I believe.
Strangely enough I can't find any references to the 4th one of the batch. However I do know it's name was " R G Laird". By a strange coincidence, a Scottish distant cousin of mine ( 1st cousin 4xRemoved ) called Robert Grimmond Laird, was shown as "Mechanical Engineer"on the 1901 census and he was living at Tan-yr-Allt Hall which is sandwiched between New Vronheulog Quarry and Tan-yr-Allt Quarry and various other workings in the Vale, and only about 1 or 2 miles from Dorothea and Pen-yr-Orsedd Quarry. Both of the nearest two are shown on the map as having sizeable rail networks, so I assume that he arranged for the purchase of a Hunslet and the quarry owners were so impressed with it that they named it after him.

So anyway, back to the model. I'm printing most of it in resin and the chassis and footplate are now off the printer, together with 2 buffer beam overlays. I'm doing it like this to take advantage of printing things flat on the plate to improve the surfaces with little or no supports to worry about. The wheels are also done, but in filament. I'm trying a new type of filament for them and I'll say more about that later.

Now with the footplate glued to the underframe and the buffer overlays alongside, this is where I am today, in primer.
I'm going to try painting the various components and sub-assembly's before putting it all together in the hope of avoiding all sorts of masking issues further down the line.

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[SimonWood]

Amazingly crisp prints really showing off all the extra detail!

Just to be clear - frames printed separately from the footplate? (And flat to the bed too, so oriented at 90 degrees to how we are seeing them?)

[philipy]

Just to be clear - frames printed separately from the footplate? (And flat to the bed too, so oriented at 90 degrees to how we are seeing them?)

The footplate was printed by itself, upside down from how it appears in this photo - a simple 2mm thick slab with a small groove on the long edges and various openings for motor etc in the slab. The U/f was printed as shown but without the footplate underneath ( obviously). Then simply superglued together, and no problems with the two perfectly flat faces mating.
Two reasons for doing it like that:
(1) There is a shallow depression on the top of the footplate in front of the smokebox, which wouldn't print if it was on the bottom ( plate) face.
(2) In the past I've had issues with doing large prints which have sidewalls, flat on the bed. The resin swirl and suction tend to cause adhesion/distortion problems.

[SimonWood]

Thanks. That combination of parts printed together hadn't occurred to me, but it makes sense.

[Peter Butler]

That does look incredibly sharp with lots of detail. Quarry Hunslets are a guaranteed winner.

[drewzero1]

Looks great so far, will be following with interest! I had originally intended Thornas to be a quarry Hunslet so I can see some things I missed or oversimplified on my version of the frame already. (Out of curiosity, how does Luna compare in size to the Hunslet?)

[philipy]

(Out of curiosity, how does Luna compare in size to the Hunslet?)

My Luna is 176mm from front buffer beam to rear of bunker. The Hunslet will be about 185 when finished. They are both 85mm wide.

[FWLR]

Going to be brilliant that again Philip.

Just wish I had a bigger bed now for printing things that length, but it's not going to happen for years yet.

Anyway, looking forward to more of your build Philip.

[philipy]

Just wish I had a bigger bed now for printing things that length, but it's not going to happen for years yet.

Yes, well I'm fortunate Rod. I couldn't have afforded the big machines myself either, but technically they both belong to SWMBO's company and were bought to do a job for a particular contract they had. It was cheaper, faster and more flexible to buy the machines and get free labour from me, than to send them out to commercial printing companies, and it would have been a shame to have them sitting idle once the contract was finished....

[philipy]

An update and admission!

Not quite sure how it happened but when I printed the footplate I seem to have used an earlier drawing rather than the final one. It was only after I printed it and glued it to the frames, painted and posted about it, that I realised the error.

There should be a row of rivets across the front of the footplate and two pairs either side of the smoke box. I did draw them but then must have grabbed an earlier drawing. I didn't really want to go back to the beginning and redo everything but 1mm diam rivets are fiddly to say the least. In the end I managed to print them at the correct final spacing, upside down and attached to a flat strip by a thin support.

IMG_0747.jpg (210.59 KiB) Viewed 447 times

A touch of superglue on each and held in tweezers and they were fixed in the correct position ( almost, they are slightly offset to the left!). Left a couple of hours to be sure then snipped off. It seems to have worked Ok and once all painted should be fine, I hope. This close up is rather cruel - bare in mind that the rivets are only 1mm!

IMG_0752.jpg (285.3 KiB) Viewed 447 times

So, moving on, The smokebox and chimney are printed. I changed Steve's original drawing and printed them seperately to reduce the printing time significantly.
Also a coal bunker and the dome/safety valve and extensions. An odd combination I know, but they all need doing and it's what fits on the build plate.

IMG_0753.jpg (450.83 KiB) Viewed 447 times

[FWLR]

Just wish I had a bigger bed now for printing things that length, but it's not going to happen for years yet.

Yes, well I'm fortunate Rod. I couldn't have afforded the big machines myself either, but technically they both belong to SWMBO's company and were bought to do a job for a particular contract they had. It was cheaper, faster and more flexible to buy the machines and get free labour from me, than to send them out to commercial printing companies, and it would have been a shame to have them sitting idle once the contract was finished....

You were lucky then Philip and it's been worth while hasn't it because you have done some amazing builds with it.

And your right, it would be a shame not to use something that's going to be laying there doing nothing...

[philipy]

Things have been trundling along and I'm making some changes and reprinting the chassis/footplate. Not that there is anything wrong with Steve's original drawings but different people do the same things in different ways. I'll come back to that when I know if my way works.

In the meantime, the cab, firebox, brake standard and reverser are now printed.

IMG_0764.jpg (548.38 KiB) Viewed 265 times

In order to save time and make use of the space, I printed all these items at the same time. The cab alone took took fractionally over 12 hours so the other items were 'free' in printing time terms.
This picture shows them still on the flexible magnetic build plate.

IMG_0758.jpg (2.57 MiB) Viewed 265 times

[drewzero1]

The "free" print time is one big selling point of a resin printer. (That and of course the detail!)

When I try printing a bunch of things at once in FDM, all I get is more points of failure.

[Peter Butler]

The surface finish on those parts is just incredible, I can't see any sign of fault or imperfection.

[philipy]

Drew,
I very rarely try printing more than one thing at a time in FDM. It's no quicker than doing them individually and as you say, more chances for things to go wrong. The only real exception, for me, is a set of wheels. Printed flat on the bed the m/c can't really get it wrong, just going round in circles!

Peter,
Thanks for the kind words. I have to admit that in fact there are imperfections, but fortunately not on the big flat surfaces where they would show, and nothing that can't be dealt with as in any other kit.

[philipy]

As a slight aside, I've been thinking about colour schemes for when I get that far. I know the preserved locos sport a variety of liveries so I wondered how fancy they were when when new. I kind of assumed that they might have been fairly ( completely?) plain darkish colours, but I've just come across this post which knocks that idea on the head.
It might be of use to anyone else thinking of building/painting a Quarry Hunslet.
https://www.westernthunder.co.uk/thread ... ies.12558/

It appears that inside of the cab of Britomart was painted in an Oak grain effect. Not sure how long that would have lasted in service!

PEN-YR-ORSEDD SLATE QUARRY
"BRITOMART" 707/1899
Painted the Midland Rly. Colour (Crimson). Inside cab grained oak.

[ge_rik]

Just out of interest, are those supports added automatically by the slicer or did you put them in manually?

Rik

[philipy]

A bit of both Rik.
I usually tell Chitubox to put them in automatically and then look at them and take out the ones that are nonsense and add a few more to be sure! I also check and edit if necessary to make sure that the support bases are clear of the model and that the verticals are clear of faces and protrusions, to avoid bridging problems. Plus, the auto added ones are whatever type was originally selected, so you can end up with a big item with thin supports or a small delicate item with massive supports and I tend to make ajudgement about what suits best. For example the thin support on the tip of the regulator handle in the picture was left off completely in auto. In theory it might not be necessary, but for something delicate and that far out on a limb, I preferred to be safe than sorry.
I added quite a few extra along the bottom edge of the cab, because I was concerned that as it grew and got heavier, it might break away if there was insufficient to anchor it.

[Old Man Aaron]

Those are some truly beautiful prints.