Hi, I'm currently designing a 4-8-2 Gresley design on stud.io with the vision of building it in real life and as such I want to make it able to traverse various radius track curves, however I also want to retain a cohesive look for the chassis. I'm not overly concerned about the tightest of curves but I would still like to go as tight as possible without compromising aesthetics. 

My current design consists of:

4x - 20.8mm (MS) leading wheels

Double Pivot

8x - 42.3mm (XXL) Driving Wheels

2x -  24mm (M) Trailing Wheels

Tender.

I was wondering about the feasibility of the design and if anyone has a similar setup, what curve sizes is their loco able to traverse?

 

Edited January 18, 20214 yr by Astro61201
Added Pictures

18 minutes ago, Astro61201 said:

Hi, I'm currently designing a 4-8-2 Gresley design...

*snip*

...I was wondering about the feasibility of the design and if anyone has a similar setup, what curve sizes is their loco able to traverse?

Gotta post some pictures of your setup. It's (imho) the most expedient way to get help.

28 minutes ago, M_slug357 said:

Gotta post some pictures of your setup. It's (imho) the most expedient way to get help.

Apologies, I have added some images to my original post.

Question: How do you get the BigBenBricks wheels into Stud.io?

1 minute ago, Trainaud(LegoRailCreaties) said:

Question: How do you get the BigBenBricks wheels into Stud.io?

Download them from his website (LDraw in the menu), then move the .dat file(s) to hard drive/ program files/ stud.io/LDraw/CustomParts

If the custom parts folder isn’t there then create one.

It is worth noting that these pieces lack connectivity features, to add them you need to import the piece into Part Designer and add an axle and pin connection, which is what I did.

34 minutes ago, Astro61201 said:

Download them from his website (LDraw in the menu), then move the .dat file(s) to hard drive/ program files/ stud.io/LDraw/CustomParts

If the custom parts folder isn’t there then create one.

It is worth noting that these pieces lack connectivity features, to add them you need to import the piece into Part Designer and add an axle and pin connection, which is what I did.

Thank you for the help.

So long as your leading and trailing bogies pivot you should be able to negotiate Lego curves just fine...do you have a setup with track curves tighter than that?. You may have to tighten up your main drivers so the blind wheel overlaps the flange slightly. This results in axles 5 studs apart. I'm in the middle of a potential move and my track is packed away so I can't test it. Does this answer your question?

Edited January 20, 20214 yr by CDM

23 hours ago, CDM said:

23 hours ago, CDM said:

So long as your leading and trailing bogies pivot you should be able to negotiate Lego curves just fine...do you have a setup with track curves tighter than that?. You may have to tighten up your main drivers so the blind wheel overlaps the flange slightly. This results in axles 5 studs apart. I'm in the middle of a potential move and my track is packed away so I can't test it. Does this answer your question?

Thanks for your answer, I’m aiming for a minimum curve radius of about R56 or R72, do you think this would be possible?

Edited January 21, 20214 yr by Astro61201
Quoted Twice

19 hours ago, Astro61201 said:

Thanks for your answer, I’m aiming for a minimum curve radius of about R56 or R72, do you think this would be possible?

I would think so. Lego R40 tracks are unrealistically tight and it should work on that. Anything with a larger radii would be fine. I may get some track out this week to test a build of my own. I'll play around and report back.

Wait, aren't XXLs restricted to higher radius curves? I thought I read somewhere that the XXLs were not able to take R40s due to their size.

 

59 minutes ago, High_Admiral said:

Wait, aren't XXLs restricted to higher radius curves? I thought I read somewhere that the XXLs were not able to take R40s due to their size.

 

You may be right. I mistakenly thought my drivers were the XXL but are in fact 37/30mm. My apologies. 

Edited January 22, 20214 yr by CDM

If you KNOW you are going to build this and you are going to get the track, I'd suggest you get the wheels and enough track to start prototyping the frame. There are so many nuanced things that complicate frame building (e.g., pilot truck clearing the cylinders). Of course you are doing the right thing by asking questions to make sure it is even feasible before buying anything. If that is the case, perhaps rephrasing the question to be about the wheels in general,

"Using XXL wheels with a spacing of 6 studs axle to axle (5 studs center to center), what is the tightest curve any of you are able to run on?"

If this is your first steam MOC and you don't have any parts yet, you might want to start with something simpler first (L wheels) and keep this for your second steam MOC.

14 minutes ago, zephyr1934 said:

If you KNOW you are going to build this and you are going to get the track, I'd suggest you get the wheels and enough track to start prototyping the frame. There are so many nuanced things that complicate frame building (e.g., pilot truck clearing the cylinders). Of course you are doing the right thing by asking questions to make sure it is even feasible before buying anything. If that is the case, perhaps rephrasing the question to be about the wheels in general,

"Using XXL wheels with a spacing of 6 studs axle to axle (5 studs center to center), what is the tightest curve any of you are able to run on?"

If this is your first steam MOC and you don't have any parts yet, you might want to start with something simpler first (L wheels) and keep this for your second steam MOC.

Thank you for your advice, I think prototyping is the best way to go.

On 1/18/2021 at 4:52 PM, Astro61201 said:

Hi, I'm currently designing a 4-8-2 Gresley design on stud.io with the vision of building it in real life and as such I want to make it able to traverse various radius track curves, however I also want to retain a cohesive look for the chassis. I'm not overly concerned about the tightest of curves but I would still like to go as tight as possible without compromising aesthetics. 

My current design consists of:

4x - 20.8mm (MS) leading wheels

Double Pivot

8x - 42.3mm (XXL) Driving Wheels

2x -  24mm (M) Trailing Wheels

Tender.

I was wondering about the feasibility of the design and if anyone has a similar setup, what curve sizes is their loco able to traverse?

 

 

I have a question. Where did you get the file for the MS leading wheels? I am looking for these wheels in digital form for stud.io.