Highland Railway Drummond 0-4-4T Passenger Tank

Hi Bob

As these ones are min, once done i'll send you a set of the STL's, or the sliced file it's up to you.

Doing a bit of accupuncture



This will create the holes for the Handrail knobs and smokebox door - holes 1.0mm will probably end up being approx 0.8mm after printing but are easily drilled out.



Looking at the underside - notice the cab handrails pass through the valance, I think I will try to print the hand rails and see how they come out.



For those wondering about the two hex holes and the central hole under the cab - I have a plan

I am goiny to try and etch an assembly that will have the steps and be attached via a pair of nuts glued in to the body. The center hole is to clear a height adjusting screw for the chassis / bogie rubbing plate.

This feels like I may be ready to try a test print - fingers crossed

Paul

 

It'll be a tomorrow morning job to the result - estimated 10h 57m, don't think I'll wait up



Sliced using Lychee Slicer.

Next job will be the smokebox door, but need to get some brownie points in the bag before going awol again in the cave - the sacrifices we have to make for our hobby

Paul

 

Mixed results - although I wasn't expecting it to be right first time, and was aware of some short commings.

11h 5 mins (according to the display) - was in bed when it completed, I know nae dedication, but I am getting old.

I did see some issues duirng the print with the footplate and noticed the tank fillers were missing

Now I remember having issues with the tank fillers been missing before, and found that there was gap between the tank filler and the tank itself - less than 0.1mm but enough for it not to be able to stick (effectively printing in thin air). I'd forgot about that, as I had to an older version of the models to rebuild the model as a 1 piece print.

When removing the supports the front bufferbeam and foot plate snapped off - hardly surprising when the footplate is only 0.5mm thick. I've taped the footplate back in place to show the buffer beam and valance as I think they look nae too bad

Next bit I was impressed with was the Cab hand rails, looks like these will remain printed

I will check some of the earlier prints for the transition between the chimney and domes to the boiler and smoke box, as in this print it's smooth, if they were there before it may be a cure time issue.

As mentiond in the previous posts the tank sides will need bulking up, as they were deformed. They may also have been effected by the supports. I had used the auto support feature, which seemed to have prioritized the inner areas and not the valance.

The footplate between the valances will be increased to 1mm thick, and will also apply a fillet between the indise of the valance and the footplate to help strengthen the area.

Need to add a few more holes for detail parts, and decide whether the Chimney, dome and tank fillers will be printed in place or printed seperately.

I will give this print a quick sanding and a spray of Vallejo grey surface primer, just to see how it looks.

Paul

 

Hi Gormo - fingers crossed

First job - tank fillers



As suspected there was a gap - 0.28mm

Tank filler separated from the build, moved down 0.3mm and a 0.1mm radius fillet applied (this is also a good way to make sure the two have mated as the fillet will go the wrong way if the two aren't joined up - lesson learned)



Now the under side for the valance and front footplate strengthening and Tank side thickening

A 2mm slab was added to each tank side after the over lap gives a thickes of about 2.5mm, I will make up some support frames that can be removed if space is required for motors etc, they will only have a 0.5 mm thick connection so can be easily cut out, but will provide support during the build process.

Next up a 1mm thick brace fitted to the underside of the front footplate, and along the length of the valance. A 45 degree chamfer was applied to the edge.
Finally a 2mm radius fillet was applied between the joint of the bracing and the valance.



More finger crossing, as I think I will try another test print, but just incase this is a gudun, I will add the holes to the smokebox front for a couple of fittings.

Paul

 

Ok, ready for another test print



Trying a couple of tests at the same time, printing horizontally to save time and also without anti-aliasing enabled to see the effect on the model - last print it was set at 8.




The last print the undersides of the prints were'nt pretty although not seen I'd like to fix it. One of the causes can be overexposing the resin, so I have cut the exposure time to 1.6 seconds.
I've also increased the raise and lower speeds, raise speed increased from 2mm/s to 3mm/s, so with 8mm raise height it should take approx 3 seconds to lift, and increased the lower speed from 4mm/s to 6mm/s so approx 1.5 seconds total time of 4.5 sec to raise and lower. I have set the stop time to 8 sec, this should give the build plate 3.5 s to settle - we'll see.

Estimated time to print is 5h.

Just need to level the build plate before starting.

Paul

 

Cheers Paul

Just started the print so - the software estimated 5h18sec, the printer estimates 5h48min, think I believe the printer, so I maybe a happy bunny at bed time

Paul

 

Nuts - not the edible kind

Paused the print to check, and the footplate had started to detach

Trying the print this time sliced with Chitubox,



There is now a profile available from Chitubox for the Mono X

I have increased the cure time from 1.6s to 2.2s and used the following settings





interestingly, Chitubox allows different settings for the normal layer and bottom layer speeds.

estimated print time 5h59m56s - printer reckons 9h56m to go

Paul

 

Hi Gormo,

Your spot on, to the point where on some of the forums, when giving print settings they include tempreture and location they are printing.

My intension is to move the printers into the shed - get rid of the fumes, but will build an insulated type of fume cupboard, with its own extractor fan and Electric oil filled Radiator.
The radiator will be set to maintain a minimum temp, and the extractor fan, to either clear out the fumes at the end of a print (before I open the doors) or in summer when the temp may rise above freezing to clear out the hot air.

Seemingly its more sensitive to resin temp at the start of the print, but doesn't like the cold - that's me gubbed then.

The UV light does pump out a fair amount of heat, so this may explain the sensitivity at the start before the lamp has heated up the resin.

Paul

 

Just checking before heading for bed

We're up to layer 1067 out of 2089 with an estimated 4h52 to go, so should be completed for when I get up



The bit appearing as the build plate rises looks just like the preview, but is the other way up.

oooo the excitement, i'll not be able to sleep - nah don't think so

Paul

 

And it finished 10h 15m

Removed from the print bed

Cleaning was fun as its too big for my wash baths while the supports are in place, so a couple of stints in the ultrasonic cleaner.

The supports were removed, then given a rinse in the 2nd wash bath with IPA (a pickle container), then into the Wash & Cure machine, 2 x 6min washes again in IPA.

Allowed to dry for a couple of hours (coffee plus walk the dog ), also allows the fume level to drop - it's too cold to open the windows.

Cure time

4 mins in cure mode

Then I used the nail curer to do the ends, the models are too large to lie flat - 2 x 100 seconds on each end, and a final 4 min cure in the wash & cure machine.

And the final model

Nuts - I forgot the hole for the handrail knob, not sure for lamp brackets, as they were different for HR/LMS/BR, so an addon I think.

Note also the bottom edge of the buffer beam, think I need to add more supports, with heavier supports at the ends

Note the paler areas around the windows, this is because there is a gap between the font and back faces, to allow me to insert an 18 x 18 glass slide cover as the glazing, and this canbe done after painting.

and finally the main issue / fail

The valance, is stepped, probably fixed with more supports, but I also think I need to raise the print angle to 45 degrees, this will impact the print time but should give a far better print.

Next up, add the handrail hole, then create the smokebox door, Vacuum pipes, sandboxes, brake shoes and other fittings, all to avoid having to start the chassis.

Paul

 

Hi Bazzmund

Dunrobin, was the Duke of Sutherlands own private Loco, and was never actually part of the Highland railway stock, but was designed by David Jones (of Jones Goods fame) and built by Sharp Stewart. Built in July 1895, it remained in the Sutherlands ownership until nationalisation, when access to the main line was forbidden. In 1949, it was sold to Capt. Howey and moved to Kent, In March 1965 it was sold to Imperial Pagents Ltd and shipped to Victoria, British Columbia, then sold again in November 65 to the British Columbia Goverment location Fort Steel British Columbia. In use it would normally be seen towing the Duke's own saloon car. Luxury abounded, the cab was fully glazed non of this fresh air malarky.

The Highland Railway Passenger tank I'm making was designed by Peter Drummond, and built between March 1905 to Feb 1906, 4 in the class, and were the last class of locomotives built at Lochgorm works. 3 survived into BR, HR No. 45 (LMS 15053, BR 55053) was the last HR loco in service when it's axel broke, and was replaced by a GWR 16xx .


Hi WalkingtheDog

The potential is amazing, and the cost is plumeting. The process has a somewhat steep learning curve, not only the design of the model, but the tweaking of the process to get the correct result. But is well worth the effort (in my opinion that is), I now have 3 Resin printers 2 x Anycubic Photons (approx 6" build plate) and my new Anycubic Mono X (approx 9" build plate). There are resin printers with larger build plates (12 -13") but cost between two and three thousand pounds, so might be on the wish list but will be on the list for some time.
Great thing is you can start small and work up to bigger and braver things. I'm not trained in CAD or 3D modelling, and have picked up bits by trial and lots of errors, one day I may even know what I'm doing

You can download free software and play designing your own bits, can even get them made by company's such as Shapeways.

Go on give it a go

Paul