Jump to content
 

Nm9 RhB modules and standards


PaulRhB
 Share

Recommended Posts

  • RMweb Premium
3 hours ago, PaulRhB said:

Just a reminder that Jon and I will be at Globalrail this Saturday with these BonsaiRhB modules and discussing setting up a wider Nm9 standard for group meets, come and have a chat  :) 

Love to - but its just too far South for me. Hope it goes well for you and hope you will keep us all up to date with developments regarding the standards.

Link to post
Share on other sites

Well, some excess HO got sold today and a basic 10-1145 set and unitrack oval was ordered.

It's likely I won't be building a module first-off - one of my aims with this is I want to try and give Sophie the chance to build a small layout with me, and that'll give me a good incentive to build some stock (she definitely wants a model of the ice cream container. :rolleyes:

That should let me get my head around it's capabilities before I do a module too, plus give the spec a chance to solidify a bit as well.

  • Like 1
Link to post
Share on other sites

  • RMweb Gold

The refrigerated containers are available in 1/160 but you’ll probably need to make transfers to do the Frisco ice cream one as I’ve not seen any. 

Maybe something like my scenery test piece that started my BonsaiRhB module thread off? That’d be fun to build together, nice n messy ;) 

Edited by PaulRhB
  • Like 1
Link to post
Share on other sites

  • RMweb Gold

Ok as we didn’t get to discuss this in person here’s an idea I’ve been musing on this week. 

The profile in red is influenced by the FREMO profile but more by the size of the INGAnetNG one I’ve overlaid it on. 

 

B2ECE0DE-441E-4840-8AAC-79A2C05A5124.jpeg.05da99118dfc26971d2d6b14d90dd113.jpeg

My concern with FREMO was the width which makes getting several in a car for a meet more difficult. This is going to be a small niche group so getting a more narrower plain run modules in is going to be very useful. Beyond the profile the board can go as wide as you want too. 

 

My concern with INGAnetNG is the depth. Stacking two together instantly puts you at 600mm tall without allowance for trees and from my car boot that would severely limit the length that will fit in. 

 

So my idea takes on the suggestion by Martyn of 300mm to use commercial boards if you want to with our own laser cut ends. (I’m guessing from photos that Tim Horn’s are 100mm deep so it may require asking for a modified shallow frame)

I’d also suggest we have a completely flat profile and possibly an embankment one too like FREMO.

The shallower profiles are easier to transition to mountain or valley type scenery. 

100mm gives plenty of room for point motors, like Cobalts, below track level.

The smaller size should allow at least four boards boxed in pairs in most average car boots. 

 

Discuss ;) 

Edited by PaulRhB
  • Like 1
Link to post
Share on other sites

Can I just skip back a step to first principles - connections?

In HO we use clamps - giving a very simple (no need for absolute precision) end construction and very simple adjustment, the only section of that we have occasional issues (due to precision actually being needed!) is with double track ends. With single track, we can just adjust the joint to take account of any imprecision in the track laying. A deeper module end (such as the asymmetric one) with clamps should be possible but may need a (precision?) slot to get a clamp through.

Having the end profiles laser cut gives you a precise end, that gives the possibility of having precision holes for bolts to connect boards. So far so good.

BUT - This will mean that the relationship between bolt holes and rails becomes a (reasonably) precision measurement - potentially a track slightly out of level (one rail higher than the other) or both rails mounted slightly high or low relative to the bolt holes could be an issue  - are we okay with that?

I think it's worth flagging that - but I'm going to move on with this post in the assumption that we are okay with it and that we will choose a bolted connection - we can always skip back and explore the clamp alternative later.

Assuming bolted boards, then logically we need to have a minimum number of holes to cover all scenarios. I do think it should be our intention that any two module ends can physically be connected if necessary, even if that doesn't look pretty and we would try and avoid mating mismatched ones in practice.

So we should include the minimum number of holes to do that, but not all ends will be able to have (or need to have) an equivalent hole on the connecting module (the asymmetric hillside may have fresh-air on the downhill side where the connecting module has a bolt hole).

All joints will need a minimum of 2 bolts, some might benefit from a third (or more) to pull scenery together? The bigger the end I suspect the more holes it will need!

Given all that - I suspect the position of those holes relative to the track will somewhat define the majority of what is possible on the symmetrical ends.

A "plain" flat or cutting end can both have a straight line of bolt holes across it below track level and be quite compact, and most of the same boltholes will also work on the 'uphill' side of the asymmetric board - but if we ever wanted to do a symmetrical embankment the bolt holes would have to be further vertically from the track - that would force all other boards to have a deeper end also to keep the bolt hole to track dimensions the same - so we need to be careful there, even if an embankment board is not chosen right now, what we do with the bolt holes will define whether it is possible in future by the trade-offs we make now.

I'll try and knock up a visual.



 

Link to post
Share on other sites

14 hours ago, PaulRhB said:

The smaller size should allow at least four boards boxed in pairs in most average car boots.  


Virtually every car on the market has more than 3' between the wheel arches, so if we have a nominally 1' wide board you will be able to put 3 pairs across, so a total of 6 boards. You may lose a bit if some/all are curved though.

You'd get 2x 18" HO boards across by the length of the clear length of the load bed, so this gives you a third extra module length (ignoring scale difference etc!) over the HO scale. I load my HO Nucor module (3' boards) transverse in a Meriva (small car but decent load bed) and I reckon I'd easily get 4x pairs (8 boards) of 3' x 1' straights in easily, and could possibly push that to 5 pairs*.

(I don't have space to store 5x RHB board pairs and my HO ones, so don't expect me to build that much, but....) :lol:

Link to post
Share on other sites

On the comparison of the ends, unfortunately this is the downside of a slightly wider profile is it translates to taller on the asymmetric end!

I'd go for a slope between those two, but slightly closer to the INGAnetNG one than the fremo one, maybe take 1/3rd of the difference off?

I agree with what you're saying on depth, (though ultimately it'll be down to individual users what they can build, store and move!) but I suspect you can cull the majority of the board "base" from the INGAnetNG one as there is no need for it to connect to anything else down there. The vertical fascia on the 'downhill' side only needs to be enough to give the board some structure, and maybe attach a curtain in case of exhibition use - it doesn't have to be 72 high as drawn?

With those mods I think you could lose a lot of that difference.

  • Like 1
Link to post
Share on other sites

  • RMweb Gold

Ok on the baseboard width my car is 890mm due to a plastic moulding for the rear boot cover so you have to be careful where you measure as it can restrict width on just a small area. I fell foul of it with my OO layout where the second trolley would have to be forced in and end up damaging it or the car ;)

On the bolt vs clamp that’s one reason to reduce the depth from the INGAnetNG profile. I suppose you could laser cut a slot to allow a clamp to be inserted sideways and turned?

On my BonsaiRhB ends I’ve got three 8mm holes and I made a tool that goes in the slot to align the track. On the boards I’ve done that means I’ve got perfect alignment but it would mean making a standard tool everyone could get. What I have as backup though are 6mm bolts that will allow approx +/-2mm adjustment as both ends have 2mm ‘slop’ so that’s an option rather than having to distribute a tool. 

  • Like 1
Link to post
Share on other sites

  • RMweb Gold

It would be nice to make it easy to use something like the Tim Horn boards if people want to with minimum alteration so maybe no holes, and clamps is better, which we could allow for or people just use a Nm9 end as a drilling jig on commercial boards? 

  • Like 2
Link to post
Share on other sites

  • RMweb Gold

On the bolt holes a triangular arrangement with one near track level and two lower down should allow asymmetric, embankment or flat ends to all match. The top hole just to endure no big gap but rely on the two lower ones to ‘lock’ the boards?

  • Like 1
Link to post
Share on other sites

Hope this works and makes sense, this was what I was thinking, 7 potential holes, though any given end will have max 5.

 

I've only drawn flat, slope and cutting on this, a flat one side and slope the other would be easily possible too but an embankment might not be doable...?IMG_20190616_160001.jpg.4fb5c4a46fb3afa3fad2e825d25698b6.jpg

  • Like 1
Link to post
Share on other sites

35 minutes ago, PaulRhB said:

It would be nice to make it easy to use something like the Tim Horn boards if people want to with minimum alteration so maybe no holes, and clamps is better, which we could allow for or people just use a Nm9 end as a drilling jig on commercial boards? 

 

Yep I was thinking you could use that (on the cutting or flat versions anyhow, the slope won't work) with a laser cut end overlaid to give accurate hole spacings versus track.

Link to post
Share on other sites

  • RMweb Gold
23 minutes ago, Glorious NSE said:

IMG_20190616_160001.jpg.4fb5c4a46fb3afa3fad2e825d25698b6.jpg

 I think holes D, F & G would actually cover all well enough and be easy to get to. A & B would get buried in the scenery? On my HOm RhB layout I had higher holes that I never actually used because they were virtually impossible to do up as space was so tight. It worked fine like that for years on the circuit. 

Link to post
Share on other sites

I'd envisaged F and G being lower than the straight ends, keeping the ends slim?

 

If they were deeper then yes that might work, and a deep end would allow for a symmetrical embankment. (Another trade-off?)

 

The upper one is there to pull together scenery if you get a gigantic chasm, not that much of an issue at a meet but I suspect more useful at a show. You wouldnt *have* to use them, but they give that capability if you needed it.

 

We had a joint back on Rock Springs which needed one up there to pull the scenery together at the top. (And yes, that was also a pain to get to, but it did get rid of the gigantic fault line between boards which showed up at that board joint without it.)

  • Like 1
Link to post
Share on other sites

I think A&B might have a use in allowing slightly warped scenery to be tightened together, but equally my existing modules hide that sort of location behind expanded polystyrene, and I think forcing scenery togethe r at the top edge will probably be detrimental to the quality of alignment at the trackbed, which should always be first priority.

 

I've drawn a 300mm wide profile over the top of my 200mm wide modue end to give a comparison. the steepest gradient can't bisect the trackbed and make both corners.

 

I havent put any man-made part enbankment/cutaway of retaining wall detail into the profiles.

 

jon

image.png

  • Like 2
Link to post
Share on other sites

  • RMweb Gold

I suppose the other way to get at them at the top would be from the side with a blanking plug to cover them if you wanted to hide them?

This shows the difference between the two existing standards and I think the FREMO, at the front would be steep enough to blend with most but I see Martyn’s point of halfway between the two. 

B50225D6-E1B7-482C-A638-A6340621CC8D.jpeg.9c03242ae50f07e509145e8ed60ca752.jpeg

 

On Jon’s diagram as he said the steeper gradients don’t bisect the full width unless we go very tall, like INGAnetNG.

I think we need to think about structural considerations or I can see boards twisting so a flat lower edge would seem preferable even if it eats up another 40-50mm depth?

We could go with several ends but it’s going to get expensive if we get them laser cut unless Jon could do them to order? I use G&H and have to order in batches of 12 up to make it viable. Flat ends aren’t a problem as such but to use commercial boards we would still need another profile to act as a drilling jig. 

Jon’s T arrangement of bolt holes is interesting as they would cover alignment and twist for deep or shallower profiles. 

  • Like 1
Link to post
Share on other sites

I think that shows that actually provided the end profile looked 'tidy' or 'neutral' the occasional miss-match at the end of boards is OK with me (in this context) if I can accept that the world suddenly drops off in 150mm either side of the track, I can accept a jump like that.

 

26 minutes ago, PaulRhB said:

I

B50225D6-E1B7-482C-A638-A6340621CC8D.jpeg.9c03242ae50f07e509145e8ed60ca752.jpeg

 

 

 

 

 

Quote

I think we need to think about structural considerations or I can see boards twisting so a flat lower edge would seem preferable even if it eats up another 40-50mm depth?

 

 

I think you could go as low as 20mm - which it what the 'gutters' are on mine, but I'll accept my boards aren't very long, so don't need that much strength!

 

Quote

We could go with several ends but it’s going to get expensive if we get them laser cut unless Jon could do them to order? I use G&H and have to order in batches of 12 up to make it viable.

 

I have access to the laser cutter for about another ~9 months, after that it depends if I join a new makerspace in Reading, buy my own (which is a possibility) or periodically go back to Richmond. 

 

If we reach a decision I don't mind cutting a starter stock (probably in 6mm ply), although as the idea is to de-clutter before moving, I'm not sure I want too many on hand!

 

Quote

Flat ends aren’t a problem as such but to use commercial boards we would still need another profile to act as a drilling jig. 

 

again I don't mind doing a starter set of a dozen of those

 

Quote

Jon’s T arrangement of bolt holes is interesting as they would cover alignment and twist for deep or shallower profiles. 

 

I concluded with my asymmetric boards that they could in extremis be used to create a 90° swing, but that would only have 1 bolt that the joint would tend to rotate about. I think a high and low on the centre line has a lot to recommend it - after that it depends if you think there will be multiple tracks crossing the board joints (which I doubt at the end of modules)  an upper bolt to hold the trackbed tight, and then two outer bolts lower down would be OK?

 

Jon

  • Like 1
Link to post
Share on other sites

Just a thought, but if going with Tim Horn just for the ends, there's nothing to stop you getting 6mm bolt holes added as part of the cut once you're happy with all the profile designs and have all the holes in the same place relative to the track. That size hole wouldn't stop you from using g-clamps instead if there are some alignment issues.

 

I don't think he'd have too much of a minimum order issue either, especially as there's minimal design work required really as you'd have very accurate measurements to send at this rate! It's no different to a couple of little jobs he's done for me, once the design is final I'm tempted to knock up a simple one just for a standard gauge photo plank which would obviously be compatible with what you're doing.

Link to post
Share on other sites

Can't see that making up a double track standard is worth it for this, I think only one reasonably long stretch (West from Chur) seems to be double track at the moment, yes there are other bits of double track but none seem so long you couldn't build them within a module set if that's what you wanted.

 

 

  • Agree 1
Link to post
Share on other sites

  • RMweb Gold

As Martyn says the double track is minimal around Chur and would only really apply to near flat boards so we could include it to the side on those? They have building long dynamic loops at a lot of major passing points. They are integral to the station though so I don’t see them as particularly useful as a set end. 

  • Like 1
  • Agree 1
Link to post
Share on other sites

and from the above what I might propose as my prefered 'steep' profile, which I realise is somewhat concave, but I think that might work...

 

image.png.b365d0ae56196cb9d58e102c74dd350c.png

 

probably needs a few more bolt holes...

 

jn

Edited by jonhall
  • Like 1
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...