7mm Mickoo's Commercial Workbench

[mickoo]

Mid week update on the Garratt.

First off the ash pan saga, new mud ring fitted and then a 3D print of the ash pan made up and fitted.



There are no fixings in the kit so I simply added two plates and fixed screws up from below, the nuts are important, they stop the screws falling out and space the ashpan the correct distance from the bed plate.

And from below.



CCU visited when I cut back the mud ring at the front So I'm going to have to graft a small strip along the front and blend it in, not too hard, just annoying. It also looks like the print has got damaged around the corner washout plug bosses, eventually some square rod will go in these to replicate the plugs.

Fitted to the boiler bed plate. The extra spacing means that the print no longer buts up to the floor sheet, I'll make a new print with higher front and rear to seam the gaps. In reality I think there should be cross stretchers here so I might add them instead.

The damper doors are going on the etch I'm working up, as will the double row riveted strengthening straps, much easier to etch these than cut by hand.

I'm not happy with the large flat plate that supports the brake trunnion hanger, it's coming out and four oblong holes with rounded corners are going in, this area closely matches the SAR GG engine so I'll replicate that set up.



Right way up, I need to adjust the stay bolt head spacing on the front corners in the vertical plane, there should be five not three visible on the side plate.



Moving on to the cab, I mentioned the kit backhead was not the right profile, so a new one in 3D was worked up, just a first off test print. I added the regulator stuffing gland as part of the main print and now need to work out which fittings I'm going to use, then add any holes or plate work to match.



Finally we come to the boiler bed plate pedestal bearings, those in the kit are just a functional bock of white metal, which kind of leaves the ends rather bare. Whilst you cannot see all of the ends, you can see enough to be offended.

Using the SAR GG casting as a rough guide I've made a new printed cast block, I've no idea if it is 100% authentic but it looks a bit better. It's only a basic test print to check fitting and needs a few tweaks here and there as well as some bolt head detail and such; it'll probably need another tweak anyway once we come to fitting to the engines as clearances are tight in here.

 

[simond]

What’s the printer, please Mick?

Seems to make some stuff very much more easily, and probably better, than brass would have done. I recall your earlier comments on the subject.

I fear I’m suffering from “tool envy”

As an aside, you’ve made the ashpan from the etch, which was clearly good enough. Where would you draw the line between 3D printing and using etch? Why not just print the ashpan too?

cheers
Simon

 

[paulc]

Hi Mick , excuse my ignorance but what is 'CCU' short hand for ? Ref the 3D printer , a friend of a mate has one and its so handy , he likes to fiddle and i pay him to make bits for me . He never asks enough in my opinion but his answer is that he gets enjoyment from making things and thats good enough for me as its the same answer i give people about building stock etc .
Cheers Paul

 

[adrian]

'CCU' short hand for ?

I presume Captain cock-up (#840)

 

[paulc]

Oh , him again . He visits me quite often . Thanks Adrian .
Cheers Paul

 

[mickoo]

What’s the printer, please Mick?

Seems to make some stuff very much more easily, and probably better, than brass would have done. I recall your earlier comments on the subject.

I fear I’m suffering from “tool envy”

As an aside, you’ve made the ashpan from the etch, which was clearly good enough. Where would you draw the line between 3D printing and using etch? Why not just print the ashpan too?

cheers
Simon

Simon,

I'd rather not divulge the printer model as it's used commercially for Finney7 stuff, hope you don't mind

What I can say though is that it's a mid range hobbyist SLA model, and there are several on the market; pretty much all of them can give you good results, but it takes time, lots of time, to find the right resin, settings and basically how to drive it. New models appear almost monthly and quality keeps getting better and costs lower so I expect this one is an antique by now.

Unlike metal or other innate objects, resin is more like a growing material, it's more akin to cake mixing and baking.

I can also say that it has it's limits, which I'm hitting more often now, therefore I'm hoping to upgrade to a Form printer, either a new 3 or recon 2 in the reasonably near future.

Regarding the ashpan, sadly I didn't make myself clear, it was not good enough by any stretch of the imagination. A fold up sides and base, plus front. All in all about 20 minutes to construct, add 10 more to make a new rear and you would have had a ashpan shaped (roughly) blob. Without the print the metal work reconstruction took just over six hours, it doesn't show though does it.......

Interesting question as to where to draw the line, mine is much further to the left field than a great many others I rub shoulders with, there is (personal observations) an air of arms length to these new whizzy fangly materials, the staunch rear guard being firmly in the "it has to be all metal to be a 'real' model".

Personally, that's really beginning to initiate me so rather than lead the horse to water, I'm just going to go drink myself, no point keeping the horse if it's just become a burden.

Mixed media is here; I personally intend to work with it, move forward with it, embrace it. I may fall flat on my face, but my gut feeling is that I'm already playing catch up to others more far sighted than I.

I don't think 3D will replace everything, I don't actually like resin boilers very much but I am very much for resin fireboxes, life is too short to spend days whittling a firebox out of sheets of metal. There are some that enjoy that craft and skill (which I respect enormously) but I'd rather print one and use the time saved to do something important.....like drink beer

Back to the model, if I were not adding partially opened damper doors, then yes, the whole ash pan could have been 3D printed. If we had this conversation a week ago then that's the route I probably would have gone down. With hindsight, you have to question whether open doors was worth all the extra effort, especially given that the original kit did not have them.....or even a rear face

The line between metal and print is hard to define, prints are in essence plastic so you need to think strength and a method of fixing them securely. So, large blobs like ashpans (and I'm going to use these a lot on future models), smokebox doors, domes, backheads, sandboxes etc are prime targets, smaller details are assessed individually.

For example, a sight glass fitting could easily be 3D printed, it's not load bearing and is in a low contact area, it'd certainly have more fidelity than most cast brass ones. The only hard part you have to think of is the hole in the base for the 0.3 mm copper wire drain.

This is a crop of a test run I did, it failed because the washout plug openings failed to drain the resin when printing, however it shows the detail you can get with a 3D print. Personally I'd be more than happy with those sight glasses and regulator rod/stuffing gland on any of my models.



Apologies for the ramble, you lit an already very short fuse

 

[Lancastrian]

Mick,

Awesome stuff.

I agree with you about some of the ideas that everything must be made from material X, or whatever. As for horses, an Italian phrase I learned, I cavalli bevono latte (the horses drink milk), which my Italian friend finds funny and is now a joke between us. When you look at the work being carried out by military modellers with dioramas etc, and virtually all in some form of plastic/resin, you have to look at how our own hobby can learn and progress into 21st Century techniques and solutions to old problems of kit design.

I will take you to task about "of" though ! It's "have"

Ian

 

[mickoo]

Mick,

I will take you to task about "of" though ! It's "have"

Ian

It ain't in Suffuk.........we wroight how wez speek

 

[Lancastrian]

It ain't in Suffuk.........we wroight how wez speek

That will be why I only venture into those parts late at night when Suffolk folk are tucked up in their beds


Dunwich beach

Ian

 

[mickoo]

I do like that photo, that stalk right in the middle would have to go though.......

Given the orange hue on the horizon I'm guessing around 04:00, would love to know your camera settings, I never get any luck with deep night shots and I want to practice before getting back to the US and into the Mojave desert, specifically the Trona pinnacles I have my sights on.

At the risk of gate crashing, give me a call next time your in the area, it'd be good to meet up and learn some new tricks.

 

[michael080]

I can also say that it has it's limits, which I'm hitting more often now, therefore I'm hoping to upgrade to a Form printer, either a new 3 or recon 2 in the reasonably near future.

Fully agree with your statement. It is a nice technology, but it has its limits, especially if people think they can print large 3d-chunks in one part

If you need a test print from a Form 2 printer, send me a stl file. I can use one at work.

Michael

 

[simond]

Simon,

I'd rather not divulge the printer model as it's used commercially for Finney7 stuff, hope you don't mind

What I can say though is that it's a mid range hobbyist SLA model, and there are several on the market; pretty much all of them can give you good results, but it takes time, lots of time, to find the right resin, settings and basically how to drive it. New models appear almost monthly and quality keeps getting better and costs lower so I expect this one is an antique by now.

Unlike metal or other innate objects, resin is more like a growing material, it's more akin to cake mixing and baking.

I can also say that it has it's limits, which I'm hitting more often now, therefore I'm hoping to upgrade to a Form printer, either a new 3 or recon 2 in the reasonably near future.

Regarding the ashpan, sadly I didn't make myself clear, it was not good enough by any stretch of the imagination. A fold up sides and base, plus front. All in all about 20 minutes to construct, add 10 more to make a new rear and you would have had a ashpan shaped (roughly) blob. Without the print the metal work reconstruction took just over six hours, it doesn't show though does it.......

Interesting question as to where to draw the line, mine is much further to the left field than a great many others I rub shoulders with, there is (personal observations) an air of arms length to these new whizzy fangly materials, the staunch rear guard being firmly in the "it has to be all metal to be a 'real' model".

Personally, that's really beginning to initiate me so rather than lead the horse to water, I'm just going to go drink myself, no point keeping the horse if it's just become a burden.

Mixed media is here; I personally intend to work with it, move forward with it, embrace it. I may fall flat on my face, but my gut feeling is that I'm already playing catch up to others more far sighted than I.

I don't think 3D will replace everything, I don't actually like resin boilers very much but I am very much for resin fireboxes, life is too short to spend days whittling a firebox out of sheets of metal. There are some that enjoy that craft and skill (which I respect enormously) but I'd rather print one and use the time saved to do something important.....like drink beer

Back to the model, if I were not adding partially opened damper doors, then yes, the whole ash pan could have been 3D printed. If we had this conversation a week ago then that's the route I probably would have gone down. With hindsight, you have to question whether open doors was worth all the extra effort, especially given that the original kit did not have them.....or even a rear face

The line between metal and print is hard to define, prints are in essence plastic so you need to think strength and a method of fixing them securely. So, large blobs like ashpans (and I'm going to use these a lot on future models), smokebox doors, domes, backheads, sandboxes etc are prime targets, smaller details are assessed individually.

For example, a sight glass fitting could easily be 3D printed, it's not load bearing and is in a low contact area, it'd certainly have more fidelity than most cast brass ones. The only hard part you have to think of is the hole in the base for the 0.3 mm copper wire drain.

This is a crop of a test run I did, it failed because the washout plug openings failed to drain the resin when printing, however it shows the detail you can get with a 3D print. Personally I'd be more than happy with those sight glasses and regulator rod/stuffing gland on any of my models.

View attachment 128179

Apologies for the ramble, you lit an already very short fuse

Mick,

thanks for the comprehensive reply! I do of course understand about naming names.

I’m completely with you about using different materials, it seems no shame to me to use a resin print when & if it does the job. If it looks bad or falls apart, then use something else, either metal or a different resin or a different technique to make the part.

And your backhead, it’s lovely. I think I’d drill out the offending plugs, and glue in a bit of square brass/microstrip/hardwood...

cheers
Simon

 

[michael mott]

Interesting question as to where to draw the line, mine is much further to the left field than a great many others I rub shoulders with, there is (personal observations) an air of arms length to these new whizzy fangly materials, the staunch rear guard being firmly in the "it has to be all metal to be a 'real' model".

A chap on another forum is building a 1/12th scale clerestory American passenger car using a variety of materials and a good chunk of it is printed. It is amazing how far the model-making community has pushed the development in fine detail, that as you say would take a great deal longer to make with soldering or machining metal.

I would invest in one myself if I were 20 years younger but my drawing skills are fairly well entrenched in 2D and the learning curves need to be carefully monitored these days. I can vicariously enjoy the progress by following along with work such as your though.

Michael

 

[mickoo]

Mick,

thanks for the comprehensive reply! I do of course understand about naming names.

I’m completely with you about using different materials, it seems no shame to me to use a resin print when & if it does the job. If it looks bad or falls apart, then use something else, either metal or a different resin or a different technique to make the part.

And your backhead, it’s lovely. I think I’d drill out the offending plugs, and glue in a bit of square brass/microstrip/hardwood...

cheers
Simon

You could, or you could revise the master and print again......though the top right plug appears to have it's recess filled with a blob of paint. This print has also failed at the edges near the top washout plugs, it should be a continuous lip around the whole backhead, 3D printing is good, but it's not infallible.



The test prints should determine what can be printed professionally, basically if a hobby printer can do it then so can a professional one which then opens doors to casting etc.

There's a bit more added to the second test, primarily to see how far I could push the machine. All of this looks fine but moving forward some parts I would not print again, the steam turret looks good but would be hard to secure the copper pipework too. The blower valve at upper left you could probably get away with as the fitting is quite chunky but a brass casting would be better.

The combined/steam delivery valves would also be better in brass as would the AWS/steam brake fitting bracket at lower left. The flange plates with holes in I'd keep as part of the main print but the steam heat gauge nut has blown through, realistically it's too small to be printed reliably, let alone add the pipework. The regulator arm I'd cast but I'd probably keep the stuffing gland as a print.

For the record (as this shows a Finney7 up coming model) I should make it clear that many of these parts are not suitable for commercial casting, that's a whole different process, these were just direct scaled prints of fittings to see and explore what could be done.

Most of the recent detailed work has gone into that project, which I cannot really show in detail for obvious reasons, however, personal projects are open safari

The future comes down to a mind set, as already noted, other modelling fields embrace mixed media more than than model railways, I personally think that's down to the way models are viewed/handled. Toy trains get quite a battering when compared to other more 'static' models.

As such, small detail parts that are likely to get broken or knocked off need to be more robust, but, the cab area is a low impact/touch environment so it is a good candidate to add some detailed printed items.

Once you get your head into it, the vastness of what can be quickly and easily printed off is staggering, so long as you are prepared to embrace it.

 

[mickoo]

Fully agree with your statement. It is a nice technology, but it has its limits, especially if people think they can print large 3d-chunks in one part

If you need a test print from a Form 2 printer, send me a stl file. I can use one at work.

Michael

Thank you for your kind offer, I'll see how things go at the moment and maybe try one of the upcoming US model 3D prints I have planned in the pipeline.

 

[mickoo]

A chap on another forum is building a 1/12th scale clerestory American passenger car using a variety of materials and a good chunk of it is printed. It is amazing how far the model-making community has pushed the development in fine detail, that as you say would take a great deal longer to make with soldering or machining metal.

I would invest in one myself if I were 20 years younger but my drawing skills are fairly well entrenched in 2D and the learning curves need to be carefully monitored these days. I can vicariously enjoy the progress by following along with work such as your though.

Michael

Indeed,

I have no objection to those that still prefer the old way, it's a hard won skill set that is to be admired, however, it is a skill set that persistently evades me , so I end up looking for other ways to compensate

 

[simond]

If it evades you, us mortals around here have no b....y chance

 

[mickoo]

If it evades you, us mortals around here have no b....y chance

Sir doest giveth me too much credit

 

[mickoo]

Moving on, it was time to deal with the overly large smokebox door.



The initial test run is just for sizing and I'm using a new resin so it's a trial for detail as well.

A very cruel close up. Overall I'm happy with the resin and detail and having run out of rattle can red oxide, bit the bullet and mixed up some Vallejo paint to squirt on.



Mixed emotions on that, over joyed at the level of finish the Vallejo paint provides, proving I haven't lost my touch, bitterly disappointed I cannot achieve the same in cellulose without much hard work and rubbing down.
It does mean though that the cellulose issues are simply a lack of knowledge in that material, as opposed to a general lack of knowledge......which I already know I suffer from occasionally

Fitted to the engine it now sits in a much better place. The flange is still too thick and will be thinned on the final render, now that I understand the resin better I can move up from tractor engineering to mid range saloon, not quite at F1 level yet though.



It's still a tad high I think, the real engine door is offset toward the top as can be seen in the crop of the image on Flickr, some of that may be a visual thing caused by the excessive thickness of the flange.



The crop also shows how badly I misjudged the overall shape of just about everything, including the lug size/profile, I simply copied the white metal one from the kit.....bad bad Panda

If we do some doodles on the crop it's clear to see that the flange (red ellipse) passes below the front deck (red line across the engine), we can also see that the door (green ellipse) probably does not....logical Mr McCoy.



The unsolved question is thus, how on earth did they tend to the bottom lug if it is below the front deck, a lift-able panel perhaps, that would be a nice detail to add.

If the above summation is true, then my door is now undersized and needs to be mid way twixt original and this test print.

 

[adrian]

Fitted to the engine it now sits in a much better place. The flange is still too thick and will be thinned on the final render, now that I understand the resin better I can move up from tractor engineering to mid range saloon, not quite at F1 level yet though.

Very impressive - do you think that the 3D print will be able to make the flange thin enough to match? It looks awfully thin to me. To match the fullsize proportions do you think a 3D print doors and lugs on a nickel-silver disc give a better representation?