Wagon chassis test

[aleopardstail]

Not sure is 3d printing technically counts as scratch building, however I did create the design from basic primitives (cubes, cylinders & spheres). early stage, but first prototype done

its a basic solebar design, lacking any details, but with the W irons and springs (cosmetic springs, this is not a functional spring chassis). added some spare wheels to see how it works.

it does roll pretty well, the axleboxes are however designed for brass bearings that have yet to arrive, I want to get the design adapted to fit them and tested before adding more details.

not bad for about two hours working with Blender then about 4 hours to print (while I went out for the evening)

[Mountain]

Excellent. Are you able to 3D print wheels as well?

[Phred]

aleopardstail wrote:
not bad for about two hours working with Blender then about 4 hours to print (while I went out for the evening)

Wow! I guess the process must speed up for multiple copies after you've done the initial setup? I know nothing about 3d printing but the wagon looks good.

[aleopardstail]

Excellent. Are you able to 3D print wheels as well?

there is no reason why not, however I would expect printed wheels to wear quite quickly, especially the axle bearings, its possible but I think metal for wheels is best

[aleopardstail]

aleopardstail wrote:
not bad for about two hours working with Blender then about 4 hours to print (while I went out for the evening)

Wow! I guess the process must speed up for multiple copies after you've done the initial setup? I know nothing about 3d printing but the wagon looks good.

print time is basically set by how high the model is, this is printed on a 45 degree angle in two dimensions to make sure it comes out square. however given the size I could probably do three at once, and maybe two as complete (or near complete) wagons

I'm going to see how this handles bearings and metal wheels, its bound to need some changes to get the bearings to fit right. once the second one is done based on that I'm going to have a go at adding brake rigging and more rivet details, some sort of coupler pockets - printed couplers are possible though the other 3d print technology, using PLA string, is likely best for that. I may just get a pack of NEM couplers though and see how it goes.

first plan is an open wagon, this chassis is a design borrowed a bit from a Bachmann one, I can probably make it better due to not having to work with injection moulding limitations so its worth a try.

I'm surprised this is actually decently strong, not as strong as injection plastic but its not brittle

[Mountain]

Excellent. Are you able to 3D print wheels as well?

there is no reason why not, however I would expect printed wheels to wear quite quickly, especially the axle bearings, its possible but I think metal for wheels is best

I was looking for a means of producing 10.5mm wheels to a budget. The thought was that all I need is the individual wheels themselves as bicycle spokes can be used for axles. I can drill out the wheel centres for the axles on my little lathe. I was wondering if such wheels could be made to a budget or if they would cost too much?

But for your 12.5mm wheels, have you considered using metal axles? Bicydle spokes do the job but buying long axles designed for other uses and cutting them down gives one dead straight axles. Bicycle spokes are not always dead straight unless new! Is just ideas in theory to save money.

[aleopardstail]

Excellent. Are you able to 3D print wheels as well?

there is no reason why not, however I would expect printed wheels to wear quite quickly, especially the axle bearings, its possible but I think metal for wheels is best

I was looking for a means of producing 10.5mm wheels to a budget. The thought was that all I need is the individual wheels themselves as bicycle spokes can be used for axles. I can drill out the wheel centres for the axles on my little lathe. I was wondering if such wheels could be made to a budget or if they would cost too much?

But for your 12.5mm wheels, have you considered using metal axles? Bicydle spokes do the job but buying long axles designed for other uses and cutting them down gives one dead straight axles. Bicycle spokes are not always dead straight unless new! Is just ideas in theory to save money.

to be honest I just bought a load of wheels of AliExpress..

it would certainly be possible to print wheels to fit to metal axles though, and if you have a lathe that could make metal tyres printing the inner part wouldn't be too hard.

the expense is the printer, mind is a Mars 3, currently circa £150 on Amazon, a wash & cure station is a good idea, and with various other sundries (gloves, IPA and of course resin) probably £350-£400 is a good set up - if you don't mind using sunlight to cure and wash in a plastic box closer to £200 but its better to get the wash & cure station. main issue is space/mess/fumes

as for cost once you have that, well a litre of the resin I use is about £18-£25 depending on whats on offer (for this who cares on the colour, paint it). now think of the actual volume of say a railway wagon (keeping in mind you can make them hollow for box vans), one litre of resin goes a long way (though you use about 50% of it was waste for supports).

that chassis my software tells me cost about £0.22 in resin, since I have the rest of the equipment already excluding wheels and couplings once the design is done its probably about £0.60 of resin, maybe a bit less for an open wagon, a van under a quid. of course they need painting as well, there are places that will custom print decals as well

I got the printer for table top gaming stuff, for example my T'au Empire stuff is virtually all printed, and the printed stuff is well over £500 had I bought the actual models. have the same for Horus Heresy, a whole slew of model counters and recently have been printing 1:1800 model ships - probably about £300 worth retail all in for maybe £100 of resin for the lot

I'm aiming to use this to make houses, walls, odds and sods of scatter stuff as well

the other printer, an Ender 3V2 was about £200 when I got it, but doesn't need anything else other than 1Kg Reels of PLA - the quality is lower, wouldn't print wagons with it. perfect for printing stuff like control panel fronts, electrical module brackets etc

[Mountain]

I would need to buy a computer to go with it. This tablet is so old I need to keep resetting it to get it to work. I can see as a long term effect, that heavy investment will reap rewards...

Though it would take many wheels to break even.

I can see how useful it is though. The only real thing is I want to try and stick to finding budget ways that others can easily copy without having expensive equipment. (Though I do have a few expensive things, I try and only use these to speed things up, and keep to ways that people can make with simple tools if that is what they have).

However I do know that with 3D printing as you state, that less than £1 a waggon is really impressive! I am watching your venture with great interest as it is fascinating to watch your progress. (I can see how it very much pays for itself in the variety of things you can make using this equipment!)

I actually want to give myself a challenge. A whole item of rolling stock complete with wheels, couplings etc for £1 or less. Can it be done if everything one does in the build is accounted for? Quite a challenge whatever route one takes!

[aleopardstail]

I would need to buy a computer to go with it. This tablet is so old I need to keep resetting it to get it to work. I can see as a long term effect, that heavy investment will reap rewards...

Though it would take many wheels to break even.

I can see how useful it is though. The only real thing is I want to try and stick to finding budget ways that others can easily copy without having expensive equipment. (Though I do have a few expensive things, I try and only use these to speed things up, and keep to ways that people can make with simple tools if that is what they have).

However I do know that with 3D printing as you state, that less than £1 a waggon is really impressive! I am watching your venture with great interest as it is fascinating to watch your progress. (I can see how it very much pays for itself in the variety of things you can make using this equipment!)

I actually want to give myself a challenge. A whole item of rolling stock complete with wheels, couplings etc for £1 or less. Can it be done if everything one does in the build is accounted for? Quite a challenge whatever route one takes!

suspect if you ignore tooling costs and focus just on materials £1 for a wagon is possible.. you have me pondering printing and testing a wheelset, resin for that is minimal

[Bigmet]

Not sure if 3d printing technically counts as scratch building...

Using tools has always been part of scratch building. We are now a long way beyond 'qualification as a craftsman required the proof test of making all the tools of your trade with which the craft skill test pieces were produced'.

...you have me pondering printing and testing a wheelset, resin for that is minimal

I can see that working well for the hub disc, plain or spoked, between a metal axle and tyre, though I have had to glue in some injection moulded hubs now past 40 years in use, loose due to 'shrinkage' uncharacterised. A 'full life' test of a printed tyre on metal rails would be interesting.

[aleopardstail]

Not sure if 3d printing technically counts as scratch building...

Using tools has always been part of scratch building. We are now a long way beyond 'qualification as a craftsman required the proof test of making all the tools of your trade with which the craft skill test pieces were produced'.

...you have me pondering printing and testing a wheelset, resin for that is minimal

I can see that working well for the hub disc, plain or spoked, between a metal axle and tyre, though I have had to glue in some injection moulded hubs now past 40 years in use, loose due to 'shrinkage' uncharacterised. A 'full life' test of a printed tyre on metal rails would be interesting.

once I have an actual powered up loop of track (will be a while) I may have to try a wagon with printed axles and an RFID tag to count the laps and try to see how long it lasts. suspect for low speed stuff it will work. once cured its decent. may need the tougher resins though

[aleopardstail]

wheel bearings arrived, while they are a snug fit they didn't fit on one side where some residual resin had cured (my own fault, I need to order more IPA and clean the wash station out)

also the W Irons needed to be spaced further apart to allow the bearings to fit, added some basic rivet details to see how it turned out, render is thus:

its printing now, £0.24 of resin required apparently. plan is clean it up, cure it and add a shade wash to show the details, assuming the wheels fit of course


I actually have a decent quality drawing of a wagon now so the next one will be based more on reality and I hope better proportioned.

[aleopardstail]

Mk2 printed

W Irons now too far apart and need bringing in. however very free rolling with the bearings. rivet detail also worked out well. V3 will have to wait for Thursday, will be a rebuild from scratch now I have a better diagram.

quality is fine though, just flaws in the design

[Mountain]

Just a question. The axlebox assemblies. Can they be glued into position? If so, one can 3D print just them and glue them into position onto the rest of the chassis.

[aleopardstail]

Just a question. The axlebox assemblies. Can they be glued into position? If so, one can 3D print just them and glue them into position onto the rest of the chassis.

could be done pretty easily, either the boxes or the whole W iron with a suitable slot to fit into. could go for a compensated axle at one end, lots of options. thinking though once the width is sorted (its not much work to adjust it) I can basically lock it and re-use as needed. basically print a kit then build it. however if I can get the bulk as one print its a lot more accurate