I only want one chair...

[Ikcdab]

I am obvously doing something wrong. Try as I might, I cannot create a .stl file with anything in it. Each time i open the file created in Templot, it is empty.
But- all I want is one chair.
I want to print some track bases to go across a girder bridge. So these are chairs on longitudinal timbers. I can easily create the baulks in fusion 360 add a chair and copy it to create the number I need.
So all i really need is a stl file of a single standard chair to fit c&l code 75 rail.
Could anyone post me a suitable .stl file of a singe chair?
Thanks in anticipation
Ian

 

[Terry Downes]

Hi, here are stl files of a standard S1 chair with default settings straight out of Templot. Note: these are for code 75 rail and 00-SF gauge. adjustments can be made after You have printed a test chair. Hope this helps.

 

[Ikcdab]

Thank you. Of course I meant code 75. Not sure why I put code 83. I shouldn't post late at night.
Thanks again.
Second question, on such longitudinal baulk track over a steel bridge, are the chairs spaced similarly to standard cross-sleepered track?
Thanks again
Ian

 

[Martin Wynne]

@Ikcdab @Terry Downes

Hi Ian, Terry,

For use on waybeams (baulk timbers) you need L1 chairs rather than S1.

That's why they are called bridge chairs.

Generally spacings are closer than on plain track, typically 24" centres, although prototypes vary. Here are some L1 bridge chairs at Lichfield:

I will post some L1 files later, if Terry doesn't get there first.

cheers,

Martin.

 

[Ikcdab]

@Ikcdab @Terry Downes

Hi Ian, Terry,

For use on waybeams (baulk timbers) you need L1 chairs rather than S1.

That's why they are called bridge chairs.

Generally spacings are closer than on plain track, typically 24" centres, although prototypes vary. Here are some L1 bridge chairs at Lichfield:

I will post some L1 files later, if Terry doesn't get there first.

cheers,

Martin.

Hi Martin thank you. That picture is exactly what I want to do. Please can I have a dxf file as well. I just tried to import the STL file into Fusion360 and it didn't have the results I was expecting. I expect I can sort it out with some fiddling around, but I notice it has a dxf import function that might work better.
Thanks again
Ian

 

[Steve_Cornford]

Hi Ian,
Before trying to export did you save the control template to the backgound first?


You might want to read through this post https://85a.uk/templot/club/index.php?threads/lymington-town.765/#post-8694
from that point on which describes my attempt at waybeams.
Followed by Martin describing how to use the L1 chairs and the Templot Waybeam facility.

Templot can output PlugTrack waybeam timbers for FDM printing or laser cutting, and can output the correct L1 chairs for resin printing.

Steve

 

[Ikcdab]

Hi Ian,
Before trying to export did you save the control template to the backgound first?


You might want to read through this post https://85a.uk/templot/club/index.php?threads/lymington-town.765/#post-8694
from that point on which describes my attempt at waybeams.
Followed by Martin describing how to use the L1 chairs and the Templot Waybeam facility.

Templot can output PlugTrack waybeam timbers for FDM printing or laser cutting, and can output the correct L1 chairs for resin printing.

Steve

Yes I did. I think I have tried everything possible! I'll have another go at some point.

 

[Martin Wynne]

I will post some L1 files later, if Terry doesn't get there first.

@Ikcdab

Hi Ian,

Here you go. DXF and STL files for a single REA L1 bridge chair with solid jaws, in 4mm/ft scale.

Please let us know how you get on importing it into Fusion360.

STL file:

DXF file, rendered in TurboCAD. The DXF units are mm:

Files attached below.

The STL file has been mesh-fixed ready for 3D printing. The DXF file is raw from Templot and has not been mesh-fixed.

Intended for C&L code75 bullhead rail.

cheers,

Martin.

 

[Ikcdab]

Hi Martin that's very kind. Thank you.
Just got visitors, will have a go later.
Ian

 

[Phil O]

Hi Ian,

We discussed importing stl and dxf files into Fusion 360 last night after the-Zoom meeting stopped being recorded, the conclusion was that, without much reduction of the file size, it was pretty much a non starter, unless you have a paid for version.

 

[Ikcdab]

Hi Ian,

We discussed importing stl and dxf files into Fusion 360 last night after the-Zoom meeting stopped being recorded, the conclusion was that, without much reduction of the file size, it was pretty much a non starter, unless you have a paid for version.

Hi Phil, I'll have a go later, but just messing about earlier on it seemed to go ok. I used the "import mesh" function and then convert mesh to body. I then managed to copy and move it round ok.
The only issue looking like it creates about 10 bodies for the one chair. Thinking about it, I should make them a "chair" component and then I can work at the component level.
I didn't do that, but it looked hopeful.
I'll have a play later.

 

[Ikcdab]

Hi Ian,

We discussed importing stl and dxf files into Fusion 360 last night after the-Zoom meeting stopped being recorded, the conclusion was that, without much reduction of the file size, it was pretty much a non starter, unless you have a paid for version.

Hi Phil, i just tried it again. I used the file Martin sent me above and the function "import mesh".
The only issue i had was that the chair came in at 93mm (approx) across the baseplate whereas @Martin Wynne had exported it in mm for 00. Using the LMS drawings pdf, I see that the baseplate is 11" long, so it was easy to calculate a scale factor reduction. Then i could copy the mesh arond, move it and whatever.
An export to .stl then gave me the chitubox file as seen below.
All seemed to work fine for this piece with about 20 chairs. Maybe if you had a bigger or more complex file, then the PC might struggle.

But a question for @Martin Wynne about the sizing - i now have L1 chairs that are 3.667mm across the length of the baseplate (having scaled 11" down to 4mm scale). Does this sound right and i wondered why the .stl file came in so large?
Thanks to all
Ian

 

[Martin Wynne]

But a question for @Martin Wynne about the sizing - i now have L1 chairs that are 3.667mm across the length of the baseplate (having scaled 11" down to 4mm scale). Does this sound right and i wondered why the .stl file came in so large?

@Ikcdab

Hi Ian,

L1 chairs are 11" wide (i.e. measured along the rail) and 10.5" long.

In 4mm/ft scale that is 3.6667mm wide and 3.5mm long.

Those are the dimensions in the STL and DXF files. The file names included "mm" in the name to indicate this fact.

However, Fusion360, like TurboCAD and all American software before it, assumes everything is in inches. Consequently it imported the chairs at 3.6667 inches x 3.5 inches.

Which is 93.13mm x 88.9mm.

When importing a DXF file into any software, the very first thing you do is to tell it what units to use. There is always a button for this purpose on the file Open dialog.

In theory the same applies to STL files, although in practice they are always in mm, so the software ought to know this without being told.

cheers,

Martin.

 

[Ikcdab]

Hi Martin, thanks. I did indeed tell fusion360 to "treat each unit as a mm"...but that was the result. Its not a huge problem as I applied the scale factor to reduce it down.
That sounds like one of the mars landers when (apparently) ther US worked in feet, the europeans in metric and the lander crashed onto the surface. Maybe they used fusion 360 too.

 

[Phil G]

Hi Phil, i just tried it again. I used the file Martin sent me above and the function "import mesh".

Hi Ian,
Out of curiosity, when you imported the STL into F360 as import mesh, where you able to actually cut the chair up? IE to allow for chair modification. As if when using Martin's diamond crossing kludge method, where some chairs need a bit of finessing to get them looking 100% correct? Or were you just using F360 to copy and paste the chair onto a way beam arrangement as shown?

Just as a further experiment, if you don't mind. Could you see if you can open the attached DXF file in F360, its simply three sleepers with 2 x S1, S1J and L1 chairs. I can't, and I am wondering if its something I am doing wrong now.
I can't open this 3D DXF in Inkscape, FreeCad or even AutoCAD either for that matter
cheers
Phil,

 

[Terry Downes]

Phil, I don't believe dxf files can be opened within Fusion 360 (see recent Fun with CAD post). I know that STL mesh files can be imported but NOT fully edited so I suspect Ian has actually imported the stl file and just re-scaled.

I have successfully opened and can edit your dxf file into SolidWorks Maker. screen shot below.

 

[Phil G]

Hi Terry,
That sounds very promising, I can open 2D DXF in F360 see attached screen shot, but not 3D, hence I was wondering if it was me doing something wrong.
My post was only about trying to understand exactly what Ian had done. You could very well be right with your comment's though.

Its great news you can open the DXF file in Solidworks. (know you did say your were going to try in the zoom,) Can you also save it in other file formats?
cheers
Phil,

 

[Ikcdab]

Hi Ian,
Out of curiosity, when you imported the STL into F360 as import mesh, where you able to actually cut the chair up? IE to allow for chair modification. As if when using Martin's diamond crossing kludge method, where some chairs need a bit of finessing to get them looking 100% correct? Or were you just using F360 to copy and paste the chair onto a way beam arrangement as shown?

Just as a further experiment, if you don't mind. Could you see if you can open the attached DXF file in F360, its simply three sleepers with 2 x S1, S1J and L1 chairs. I can't, and I am wondering if its something I am doing wrong now.
I can't open this 3D DXF in Inkscape, FreeCad or even AutoCAD either for that matter
cheers
Phil,

Hi Phil, yes, I was only importing the .stl, then copying and pasting into the waybeam structure. see below
I was not able to manipulate the .stl.
And i found that trying to copy or pattern multiple copies of the .stl caused f360 to lock up - at least on my laptop. I guess it is a complictated feature.

I dont think it would be that difficult to draw the chair again in f360. I wil have a go at that.

 

[Ikcdab]

Hi all, I have now printed these track bases and I am pleased with the outcome

I made an error where I later shifted the transoms but forgot to move the bolt plates on the outer edges of the waybeams to match. Oh well, I've printed 20 and I'm not doing it again!

I am now concerned about how best to deck the bridge and how the decking interacts with the waybeams. Over on rmweb I have started a discussion and would welcome any comments on how to proceed.

https://www.rmweb.co.uk/forums/topic/185944-decking-for-steel-girder-bridge/

Thank you again for your help

Ian

 

[Steve_Cornford]

I've printed 20

How long is the bridge?

I can see a pair of holes this end of your print, are there corresponding pegs at the other end, or are you using some form of dowel pegs to join?
Steve

 

[Ikcdab]

How long is the bridge?

I can see a pair of holes this end of your print, are there corresponding pegs at the other end, or are you using some form of dowel pegs to join?
Steve

How long is the bridge?

I can see a pair of holes this end of your print, are there corresponding pegs at the other end, or are you using some form of dowel pegs to join?
Steve

Hi Steve, it's 1500mm double track and the track units you see here are 150mm long.
I was intending to use dowels in the holes, but threading on the rails is enough to locate to units so I won't be using locating pegs.

 

[Phil O]

Hi Ian,

I would suggest that the baulk timbers would be secured directly to the way beams. If there's a problem with the deck you wouldn't want to be taking up the track and baulks to replace them.

 

[Ikcdab]

Hi Ian,

I would suggest that the baulk timbers would be secured directly to the way beams. If there's a problem with the deck you wouldn't want to be taking up the track and baulks to replace them.

Hi Phil, thats a good point.
I have this picture of Barmouth. This appears to have timber decking and the track laid on top of the timbers. Perhaps thats why its just cost £30 million to repair.

 

[Phil O]

Hi Ian,

It certainly looks that way. I wonder what is holding it all in place? The footpath deck is looking a bit rough in places.

It's interesting to see the rail on their sides as guards, and the castings to hold it in place and the near one appears to be a steel fabrication.

 

[Ikcdab]

Hi Ian,

It certainly looks that way. I wonder what is holding it all in place? The footpath deck is looking a bit rough in places.

It's interesting to see the rail on their sides as guards, and the castings to hold it in place and the near one appears to be a steel fabrication.

Maybe the difference is that Barmouth is mostly timber rather than being a steel viaduct?