modelling 55009 in TT120

[Blefuscu]

Some initial results.

 

I have had a few issues, but I think I'll get three decent models out of this batch when I'm done cleaning them up.

 

I had a lot of warping on the first model. After reorientation, and increased support, I fixed that. However, I was then plagued with models lifting off the bed... essentially, I think my bed is level, but my FEP film has had it. I did get two good prints out of it by the end of the day though.

[tom s]

8 hours ago, Blefuscu said:

Some initial results.

 

I have had a few issues, but I think I'll get three decent models out of this batch when I'm done cleaning them up.

 

I had a lot of warping on the first model. After reorientation, and increased support, I fixed that. However, I was then plagued with models lifting off the bed... essentially, I think my bed is level, but my FEP film has had it. I did get two good prints out of it by the end of the day though.

 

 

Fantastic! They do look impressive when stacked up like a snapshot from Vulcan Foundry. My FEP just got replaced because I dropped the bed and put a tiny hole in my last one, and made a dent in the screen but oh well.

I had best my results printing the buffers horizontal separately, but they are 2mm scale ones so less thickness to support the narrow edges.

[Blefuscu]

16 hours ago, tom s said:

Fantastic! They do look impressive when stacked up like a snapshot from Vulcan Foundry. My FEP just got replaced because I dropped the bed and put a tiny hole in my last one, and made a dent in the screen but oh well.

I had best my results printing the buffers horizontal separately, but they are 2mm scale ones so less thickness to support the narrow edges.

I can see the sense of printing the buffers separately. Whilst I think I got away with it, leaving them on, it was pretty delicate work to cut away the supports there.

 

I left my grey resin in the vat for too long and I think the white pigment has settled out on the FEP. I loath emptying that thing, so I stuck it out by increasing the bottom layer times and lowering the z speed. I'm getting away with it, mostly, but small parts are a gamble. For my wipers, nameplates and horns I did a whole sheet of them just to be sure I'd have enough.

 

Last night I tried a 2mm print at 1:152 and it performed well - (not that I'm hedging my bets or anything). It retained far more detail than i expected, although the wall thickness is getting a bit thin. (0.6.. 0.4mm)

I really like it...

[tom s]

On 17/12/2023 at 18:49, Blefuscu said:

I can see the sense of printing the buffers separately. Whilst I think I got away with it, leaving them on, it was pretty delicate work to cut away the supports there.

 

I left my grey resin in the vat for too long and I think the white pigment has settled out on the FEP. I loath emptying that thing, so I stuck it out by increasing the bottom layer times and lowering the z speed. I'm getting away with it, mostly, but small parts are a gamble. For my wipers, nameplates and horns I did a whole sheet of them just to be sure I'd have enough.

 

Last night I tried a 2mm print at 1:152 and it performed well - (not that I'm hedging my bets or anything). It retained far more detail than i expected, although the wall thickness is getting a bit thin. (0.6.. 0.4mm)

I really like it...

 

I've been looking into printing all sides separately (if warping, shrinking, gap filling can be resolved) so separate buffers made sense. They are likely to break anyway so they might as well have a locating pin hole ready to slide the replacement into.

My angled print buffers tended to lose chips from the bottom of the buffer where the supports attached, whereas upright printed buffers could be supported entirely on the back face of them.

The 2mm one looks really good too! You'll end up with a russian doll of Deltics before long.

[Blefuscu]

1 hour ago, tom s said:

I've been looking into printing all sides separately (if warping, shrinking, gap filling can be resolved) so separate buffers made sense. They are likely to break anyway so they might as well have a locating pin hole ready to slide the replacement into.

My angled print buffers tended to lose chips from the bottom of the buffer where the supports attached, whereas upright printed buffers could be supported entirely on the back face of them.

The 2mm one looks really good too! You'll end up with a russian doll of Deltics before long.

I printed mine horizontally, with 'medium' supports to allieviate warping. It's not ideal, but I had some considerable warpage when I tried to print it at an angle... I'm not entirely sure if it was the model or the printer, but didn't want to risk it. I've seen this effect before on my prints that are normally ok. However, this time I know I'm asking for trouble because - until I have an idea what my chassis will look like - there's no lateral internal structure between the sides. At the least I'm thinking of putting a thicker rim along the bottom edge with temporary cross bracing to be clipped off post printing.

 

I did think about parting the model. One happy accident of printing horizontally was no support scaring on either end, the downside is some contour marks on the roof. The vents are hiding a lot of that though, so I'm still weighing up separating the roof in future. I'll see how the painting goes before I make that call. I'm keeping a bit of a snag list as I build these... and I guess this thread is partly a record of that.

I ruled out parting the ends because I couldn't see an obvious point to hide the join. I consider the nose quite a critical area!

For my coaches and EMU's, I'll probably go with a seperate roof, and maybe sides/ends, and I'd be more generous with wall thickness.

 

I see aeither path involving some model making / scratch building but it's only part of the fun.

 

I sometimes fill chips with a dap of resin on a cocktail stick before curing. Or to glue parts I've hamfisted broken . That's a good point though, the buffers will probably get broken at some point. I'll leave them on for now, but i'll export a 'spare buffer' stl. Brass buffers are also very tempting.

 

Thanks! The 2mm one has had me looking thoughtfully at the 2mm association parts list. If I see a 2nd hand co-co chassis I might go for it, but, despite the strong urge to build my own trackwork, I have the immortal words of Gold 5 in my ears; "We're too close. Stay on target"

Sadly my russian doll isn't getting any bigger. While I'm printing them horizontally I can't fit the 3mm deltic doll on the print bed. I like the idea though.

[tom s]

12 hours ago, Blefuscu said:

 

https://fft-keymodelworld.b-cdn.net/sites/keymodelworld/files/inline-images/003_update_hornby_hm195_sep23.jpg If this image is correctly scaled I'd roughly estimate the chassis width is about 19.6mm, so 1.2mm ish wall width allowed.

The class 55 does lend itself to one piece printing more than others, with the large smooth sides for sanding. The NBL diesels on the other hand have much more to impede sanding so might need the separate parts...

For flat parts I have been printing at some ideal angle someone taught me about, (I am sure it has a proper name,) but it ends up being ARCTAN(layer height/screen pixel size). For my Photon Mono it comes out as ARCTAN(0.02mm/0.051mm) = 21.413 degrees.
However for roofs I found this angle made the print just as contoured as printing horizontal, whereas printing halfway between or next along yielded best results for curved surfaces, so 10.7 degrees and around 32 degrees are my current values. Might give you a ballpark for printing rooves if you put in your layer and pixel size values.


I printed a class 16 roof profile but curved, so every 1 mm the profile rotated by 1 degree, with a marker every 5 degrees so I could observe which angles had the most acceptable finish.

Will have to remember the resin trick, would cut down on my tiny broken prints zip lock bag!

 

Edited December 19, 2023 by tom s

[Blefuscu]

11 hours ago, tom s said:

1.2mm ish wall width allowed.

Thanks for that - that's really useful to know.

 

11 hours ago, tom s said:

The NBL diesels on the other hand have much more to impede sanding so might need the separate parts

 

Yes, but that plays in our favour to some extent, as I find all the detail can hide a join (and all the contour lines) if you can find a path around it

 

I have backtracked a little since my last post. Today I have...  reinforced the borders of the model, added some temporary lateral supports, cleaned the FEP bed and am now printing a model really slowly and gently at 45 degrees with a bit of left over abs-like. It looks OK so far, 3hrs to go. Interestingly, since adding the lateral support, Anycubic's slicer wants to support the cross beams - and doesn't fill the model with supports... but it wants to put more supports outside the body, which I'm less happy about. So the surface finish should be improved... but there will be some scarring here and there. That said, while this has been printing I ran a bit of plastic putty over the contour marks, rubbed it down, and threw a coat of primer over them. They are looking really quite good now, probably not worth another photo - they are still just grey - but good enough than I'm a little excited about painting them blue.

 

On balance... I think I've improved the model today, but I would have got away with it. I will certainly have more deltics than I intended by the time I've finished. In addition to Alycidon, I've also printed nameplates for Pinza, Meld and Nimbus. I'm going to need some static bogies for the others.... and a DMU shed.

 

That research looks interesting. I should look into print alignment in more depth, it could save me a lot of filling and sanding. What was the result of the class 16 roof test?

 

There's nothing like resin for fixing resin. I used to cast in polyurethanes/polyesters and any dribbles left in the pot after a pour would fix up all the holes in the last batch.  I have repaired completely broken parts too... but you need to support them in the curer, while it is spinning!! Maybe I need a portable UV light for that.

[tom s]

10 hours ago, Blefuscu said:

I have backtracked a little since my last post. Today I have...  reinforced the borders of the model, added some temporary lateral supports, cleaned the FEP bed and am now printing a model really slowly and gently at 45 degrees with a bit of left over abs-like. It looks OK so far, 3hrs to go. Interestingly, since adding the lateral support, Anycubic's slicer wants to support the cross beams - and doesn't fill the model with supports... but it wants to put more supports outside the body, which I'm less happy about. So the surface finish should be improved... but there will be some scarring here and there. That said, while this has been printing I ran a bit of plastic putty over the contour marks, rubbed it down, and threw a coat of primer over them. They are looking really quite good now, probably not worth another photo - they are still just grey - but good enough than I'm a little excited about painting them blue.

 

On balance... I think I've improved the model today, but I would have got away with it. I will certainly have more deltics than I intended by the time I've finished. In addition to Alycidon, I've also printed nameplates for Pinza, Meld and Nimbus. I'm going to need some static bogies for the others.... and a DMU shed.

 

That research looks interesting. I should look into print alignment in more depth, it could save me a lot of filling and sanding. What was the result of the class 16 roof test?

 

CHITUBOX has so far been sensible about where to auto support models, with a few minutes of manual support placement after.
They should look good in blue, which brand are you using?


It never really showed on camera but sketched the islands of the worst contours appearing at the exact point of the ARCTAN ideal angle, so half way between at 10.7 degrees or going into the 30s and 40s of degrees look to work best for my settings, I suspect this will be the same result for all curved profiles. 


Now it has warmed up a bit I should be doing more test printing but got distracted with another model, at least the 20 has a lot of common parts with the Baby Deltic that's sitting in the to-do files...

Edited December 20, 2023 by tom s

[Blefuscu]

2 hours ago, tom s said:

CHITUBOX has so far been sensible about where to auto support models, with a few minutes of manual support placement after.
They should look good in blue, which brand are you using?


It never really showed on camera but sketched the islands of the worst contours appearing at the exact point of the ARCTAN ideal angle, so half way between at 10.7 degrees or going into the 30s and 40s of degrees look to work best for my settings, I suspect this will be the same result for all curved profiles. 


Now it has warmed up a bit I should be doing more test printing but got distracted with another model, at least the 20 has a lot of common parts with the Baby Deltic that's sitting in the to-do files...

 

I woke up to quite a nice print this morning. Here are the results at 45 degrees. My wobbly one, was about 12 degrees. That seems to concur with your experimental results.

 

I think the supports are sensible... it was just interesting how the additional 6 cross members changed the support layout. It's only a few supports on the outside of the body, but none inside now - which is great because they were a pain to clean and remove.

 

I still left the buffers on, but I think it will be ok. I'm long past expecting to freely whip off the supports like velcro! It will be a surgical operation- clipping then away from the model and filing back, like a plastic kit.

 

I'm going to stop tinkering and try and finish one of these now.

I've got some of the RailMatch acrylics ready for the blue and yellow.

 

I think the final adjustments were worthwhile though. I feel pretty confident selling this an an stl now.

 

I'm a little in two minds about charging for the files...  There's a lot to gain by allowing others to share, work on, and improve a model. Doing stuff on my own is painfully slow sometimes.

 

The flip side is that I haven't got any budget for this project... so, if she's ever going to have any wheels, or track for that matter, I'll need to put my ideology on hold.

 

I know what you mean about distraction. I've already made a significant start on the 313. The rest of the list is just folders of images and drawings. I would love to see a print of that 20 when it's ready though, it's looking great 'on screen'.

 

 

[Blefuscu]

A better view of the supports on the cross braces...

[Blefuscu]

I left some of those supports on while curing the model. When I compared this print to the standard resin prints I noticed, to my horror, that the sides had blown out slightly. I think it must have been during the final cure. The roof is thicker than the walls, so maybe it pulled the walls out of shape. The grey ones are still good enough for trackside static features I guess.

 

Edited December 20, 2023 by Blefuscu

[MikeTrice]

When you have finished curing, and even some days later, try putting the shell in very hot water and you may find it flattens any bowing.

[Blefuscu]

On 20/12/2023 at 15:17, MikeTrice said:

When you have finished curing, and even some days later, try putting the shell in very hot water and you may find it flattens any bowing.

Thanks - I will definitely try that.

 

Edit ---------------------------------------------------------------

I tried it, and it was remarkably effective! Thanks again.

 

Edited December 21, 2023 by Blefuscu
Revelations!

[tom s]

On 20/12/2023 at 11:56, Blefuscu said:

 

 

It does look impressive in the oily brown finish, all the contours look like they are in good angles to fill and sand flat too. 

Charging for it does make sense, everything in this hobby is expensive and quality stls are hard to find. I'd like to sell mine but there are so many stl sites, not sure how to find which one or ones to put it on, or how much for that matter. My budget it quite low, hence one of the reasons for modelling a 20 rather than buying a farish one. 

Thanks, the 20 has a lot of flat faces that aren't at 90 degrees so im expecting it to be a bit tricky to print without some of them suffering contours. 
Looking forward to seeing the 313 too, I lived in Brighton for university so I was quite sad to hear all the 313s have been cut up, save the 2 in preservation. Perhaps they're building an ark for EMUs?

Edited December 22, 2023 by tom s

[tom s]

With your M3 Plus's 34 micron pixels I think these would be the weird magic printing angles relative to flat, probably doesn't matter too much with whole prints but might be worth experimenting with for future projects.

Edited December 22, 2023 by tom s

[Blefuscu]

16 hours ago, tom s said:

not sure how to find which one or ones to put it on, or how much for that matter

I'm using cults3d at the moment. It's ok, I guess. They take quite a bit of commission, and hold on to your money for 30 days. Then it is released to Payoneer, who have a minimum payout of £50. I had an Etsy shop for a while, and would sell prints, but I found them worse to deal with and somehow even lost money on some sales. I soon released that if I want to scale up my printing to a point where it could become profitable I wouldn't have any time to design anything.

 

 

I've uploaded it here;

https://cults3d.com/en/3d-model/game/class-55-deltic-tt120-rescaleable-to-2mm-3mm-n-ho-oo-etc

 

I really struggle with pricing. Around £20 felt fair to me... 

 

16 hours ago, tom s said:

My budget it quite low, hence one of the reasons for modelling a 20 rather than buying a farish one. 

 

Mine too...  I don't expect to save much making loco's given the source of my parts, (need to work on that!), but I think a really decent amount of rolling stock will be much cheaper.

 

I'll make a note of those magic angles... I think a few print contours are OK though as part of the model making process, as long as it doesn't erode detail, but there's no point making it harder for myself either.

 

I might make a 313 build thread when I've made some more progress. This has been really helpful, (and  less of a solitary endeavour). I don't know the 313s as well as the 319's that replaced them, my parents are in Flitwick on the other end of the Bedford - Brighton Thameslink line, but it was sad to see them go. Since I began my research I spare them a thought every time I walk over Hornsey station and see the lines of 717s / 378s

[tom s]

11 hours ago, Blefuscu said:

I'm using cults3d at the moment. It's ok, I guess.

That does look like a good site, I have searched for wargaming figures on it before. That price does seem fair, it is currently quite niche with the lack of ready fitting chassis a potential buyer would need for a working model. My Baby Deltic might be able to be fitted to a Farish 24 chassis which I do own to size up, but the 15/16 are too short wheelbase to use the 20 or 17 RtR chassis. 
 

The angles should replicate the effect of the black line, ideally making the print look like a matt version of being printed flat, with the benefits printing at an angle gives. 
This was one of my old test prints that was done at the angle at 0.02mm layer height, it didn't need sanding at all as no contours appeared. However it did shrink at the corners, which means even though I'm keen on the separate prints it is a whole different kettle of problems to solve getting the model together. 

It is good to find a thread with a similar project to bounce ideas off of, diesel 3D printing and modelling does seem to be quite early in it's adoption in this hobby, however there are some great models being made in the earlier eras modelled.
I will probably start a build thread too when the actual models start to come together.

The blue looks great too! And with the handrails. After my 1957-61 period modelling feels complete enough I would love to move onto corporate blue era. The Tinsley or Stratford depots maybe...

Edited December 23, 2023 by tom s

[Blefuscu]

16 hours ago, tom s said:

That does look like a good site, I have searched for wargaming figures on it before. That price does seem fair, it is currently quite niche with the lack of ready fitting chassis a potential buyer would need for a working model.

Yes, there's quite a bit of wargaming on there - I've downloaded a lot more than I have had time to print, let alone paint. I realise there is going to be limited use for a body without a chassis but I felt I might as well put the listing out now as it maybe of use of other scales.

 

17 hours ago, tom s said:

one of my old test prints that was done at the angle at 0.02mm layer height

That's really good quality. I wish I had more time to experiment - I didn't think to try adjusting the layer height. I can see the shrinkage in the bottom left corner, and perhaps a little on the right there. It's just the corners though? (ie the edge is true)  The rivets don't look too far out of line though, and fi that was the case I would take the pragmatic approach and fill the gap. One of my deltic is a complete 'cut and shut' job from the ends of two failed prints - it might not be one for macro photography but I think it will be OK at a practical viewing distance.

 

Point me in the direction of your thread if I miss it. I think it's early days indeed. I haven't seen much work in other eras while I have had my head down working on this, but I do love earlier eras too. Soon, I'm sure there will be a pretty comprehensive range of models across all eras and scales - and the printers are getting better and easier to use all the time. Once I've made some headway in this area, I'm staying corporate blue, but heading up to Flitwick, near Bedford, to have a go at 45's and 127 DMU's... and some of the local buses.

 

I've just looked at the diesel allocation in Stratford depot and that looks amazing in itself.

18 hours ago, tom s said:

The blue looks great too!

Thanks, it's still only blue at the moment. I gave it a another light rub down and then some more blue today. I was hoping to start weathering it but a giant christmas jigsaw puzzle has appeared - so that's me out of action for a while. I shall emerge in a few days, have a good christmas!

[tom s]

9 hours ago, Blefuscu said:

Yes, there's quite a bit of wargaming on there - I've downloaded a lot more than I have had time to print, let alone paint. I realise there is going to be limited use for a body without a chassis but I felt I might as well put the listing out now as it maybe of use of other scales.

 

That's really good quality. I wish I had more time to experiment - I didn't think to try adjusting the layer height. I can see the shrinkage in the bottom left corner, and perhaps a little on the right there. It's just the corners though? (ie the edge is true)  The rivets don't look too far out of line though, and fi that was the case I would take the pragmatic approach and fill the gap. One of my deltic is a complete 'cut and shut' job from the ends of two failed prints - it might not be one for macro photography but I think it will be OK at a practical viewing distance.

 

Point me in the direction of your thread if I miss it. I think it's early days indeed. I haven't seen much work in other eras while I have had my head down working on this, but I do love earlier eras too. Soon, I'm sure there will be a pretty comprehensive range of models across all eras and scales - and the printers are getting better and easier to use all the time. Once I've made some headway in this area, I'm staying corporate blue, but heading up to Flitwick, near Bedford, to have a go at 45's and 127 DMU's... and some of the local buses.

 

I've just looked at the diesel allocation in Stratford depot and that looks amazing in itself.

Thanks, it's still only blue at the moment. I gave it a another light rub down and then some more blue today. I was hoping to start weathering it but a giant christmas jigsaw puzzle has appeared - so that's me out of action for a while. I shall emerge in a few days, have a good christmas!

Yeah for the body prints I have been cranking it down to 0.02 and being patient, but for the less aesthetic parts like under baseboard fittings and couplings i have just left it on 0.05mm. I was really pleased with the print, but also had some unusable class 15 parts where the corners retracted by multiple millimetres. It ended up putting me off the project for a bit but now I feel more alert to the room temperature and cure times on prints. There is also the possibility of dummy snap off skirts to put around the corners and edges to absorb the shrinking but ultimately be easy to remove and sand down the breaks like any normal support. 

Looking forward to seeing the 45 too, the enormous peaks do have a charm and look relatively straightforward to 3D model. 

Good luck with the jigsaw and merry christmas! 

[Blefuscu]

Just a mini update before the New Year...

It looks much better on the bench than in the photo and I'm really happy with this. I just wonder if I should 'stick or twist' with the weathering

The Railtec transfers are great. However, I forgot I needed two sheets of numbers and had to make a '009' from the class 09 transfers.

 

I'm going to have a crack at 3d printing some windows. Having recently seen some good results with clear resin on Instagram, really crystal clear, so I decided to trust the internet and ordered a kilo of Siraya Tech's 'simple' clear. (I wonder if I should have ordered 'craft' but the low-odour was a factor there.) I expect it will need some finishing but I hope it works, as I have rather a lot of it now. To improve the surface finish I'm going to back to Prusaslicer... I've just printed some Daleks for a friend using their 'rotate for best surface finish' and they looked really good. Still at 0.05 too... as they were printing in our kitchen and 0.02 was going to be 4hr longer. I am MUCH more aware of shrinkage and warping now though - and noticed the all the bases needed rubbing down to get them flat even though the shape of the model looked fine.

 

I think skirts and sprues might be the answer to give the shrinkage some pull in the opposite direction. Room temperature and cure times are supposely a factor during forming... but at some point surely the material needs to be fully cured and will want to shrink to the full extent of it's shrinkiness? I'm just thinking of fibreglassing or casting in polyester or wax where it's just inevitable.

 

[tom s]

Looks great with the white cabs, panel lining, weathering and decals! Good luck with the windows, I really wish resins came in smaller quantities per bottle haha

[Blefuscu]

On 31/12/2023 at 21:38, tom s said:

Looks great with the white cabs, panel lining, weathering and decals! Good luck with the windows, I really wish resins came in smaller quantities per bottle haha

Thats as close as I can get with it still looking great. In hand, there are a few flaws... on the track though it will be good enough!

 

 

For me it's the hassle of switching resin that I find the biggest drag! I'll be printing clear things for a while now.

 

Here's a test fit of the resin windows on one of the 'spare' bodies. They come out frosted. Successive layers of gloss varnish appears to clear them to some extent, as per the Siyaratech info, but they still look a bit murky. I wonder if I should attempt to polish them first but thats going to be a fiddly job...

 

Otherwise I'm pretty happy with the sirayatech clear. It's the 'simple'/ water based one. I expect the craft version is even better.

 

 

 

[natterjack]

Regarding warping issues, whilst I see plenty of external support pillars in 3D printing I do not see the use of 'sacrificial' webbing and floors to maintain dimensional stability until cured- built in jigs if you will.  Any particular reason for this?

[tom s]

2 hours ago, Blefuscu said:

Here's a test fit of the resin windows on one of the 'spare' bodies. They come out frosted. Successive layers of gloss varnish appears to clear them to some extent, as per the Siyaratech info, but they still look a bit murky. I wonder if I should attempt to polish them first but thats going to be a fiddly job...

Yeah looks good! I am reminded of car modellers on youtube who use layers and layers of varnish, finer and finer sandpapers and finally polishing compound to get the glassy finish on their models. Not sure how much of the clouding is within the material and how much is on the surface though.

[Blefuscu]

5 hours ago, natterjack said:

Regarding warping issues, whilst I see plenty of external support pillars in 3D printing I do not see the use of 'sacrificial' webbing and floors to maintain dimensional stability until cured- built in jigs if you will.  Any particular reason for this?

Because the roof section is thicker than the walls I suspected it had more pull when shrinking. It turn, perhaps this was the reason for the walls bowing out. The lateral pins I placed between the edges of the walls were to try and mitigate this. I don't know if it really helped much but it didn't hurt to try. I wasn't very scientific, as I also had to change resins at that point (from standard to ABS-like). 

 

It may be that i was overcuring the standard resin during printing, which I generally do to some extend to stop the supports ripping off. If I was going print more of these, those are the sort of tests I would start running.