SM32 Minimum radius

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steveh99
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SM32 Minimum radius

Post by steveh99 » Tue Jun 26, 2018 7:37 pm

What is the minimum recommended radius using Peco SM32 track for Roundhouse 0-4-0 locos and short wheelbase rolling stock such as tippers and 4 wheel box vans?

I am guessing the problem is the loco chassis overhang and the effect it has on the couplings that will either be choppers or link and pin.

I am looking at using 3 foot radius, could I get away with less? I think SM32 points are set for 38in radius

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tom_tom_go
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Re: SM32 Minimum radius

Post by tom_tom_go » Tue Jun 26, 2018 7:58 pm

I use these and don't have problems with Roundhouse 0-6-0 locos:

https://www.track-shack.com/acatalog/Pe ... T-605.html

I would recommend you go a big as you can though for smoother running.

CSL
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Re: SM32 Minimum radius

Post by CSL » Tue Jun 26, 2018 10:42 pm

The FAQs on the Roundhouse website state 2-foot radius "for our smaller locomotives". That said, I assume 3-ft radius as a minimum (nominally, that is - I think my rail-bending is a bit variable).

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Lonsdaler
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Re: SM32 Minimum radius

Post by Lonsdaler » Wed Jun 27, 2018 8:39 am

CSL wrote: Tue Jun 26, 2018 10:42 pm The FAQs on the Roundhouse website state 2-foot radius "for our smaller locomotives". That said, I assume 3-ft radius as a minimum (nominally, that is - I think my rail-bending is a bit variable).
Yes indeed. I've tried to stick to a minimum of 38" radius, but as you say, some of the bending is a bit variable! :roll:
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SimonWood
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Re: SM32 Minimum radius

Post by SimonWood » Wed Jun 27, 2018 10:59 am

John Rogers' Pigsty Hill is laid with 14" radius Faller track. He runs a Roundhouse Bertie round it with no apparent issues. (Videos on Facebook for those who are willing to go there.)

The Bertie has a very short wheelbase - a Millie wouldn't do a curve that tight.

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Re: SM32 Minimum radius

Post by Dasher » Mon Jul 09, 2018 8:12 pm

I'm using quite few of the SM32 "standard" curves - which are 2' 6" radius. I have at least one long arc formed of 5 single lengths (150 degrees) and several other places where two the three lengths are fastened together (60-90 degrees). My Roundhouse 0-4-0 (Jack) goes round without any issues - but I certainly wouldn't take them on at any speed. I can't comment regarding links to rolling stock as I've yet to purchase some.

I'm intending to run Brandbright "Premier" 4 wheeled (short wheelbase) stock and if these don't negotiate the Peco standard set track curves then I need to know before buying a rake of them!
Last edited by Dasher on Wed Jul 11, 2018 10:51 pm, edited 1 time in total.

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IanC
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Re: SM32 Minimum radius

Post by IanC » Tue Jul 10, 2018 9:36 am

My Lady Anne is quite happy on Mamod track. I believe the curves are 2'6". I do have some Newqida coaches and a bogie wagon, but I haven't tested them on small radius trackwork.

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FWLR
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Re: SM32 Minimum radius

Post by FWLR » Wed Jul 11, 2018 8:55 am

Hi Steve, it all depends on how much room you have, allowed to have :thumb right: I would go with has wide as possible though like most of the members have said.

On my old line before we moved i was lucky enough to be able to have some straights in the line, which only had 2 of the new Peco curves you can buy now, I think they are 38”, ST-607 No2 Radius.

If you are intending to have people round for steam up’s, it is best to go as wide as possible, because they may have longer wheelbase’s than you have, so if your’s where to small, they wouldn’t be able to run their loco’s or rolling stock.

Hope this helps.

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Re: SM32 Minimum radius

Post by DonW » Mon Jul 22, 2019 5:39 pm

It is surprising what you can get away with on sharp curves. Things to what though are clearances on curved platforms. A new coach a bit longer than your existing ones can be a sudden problem.
Couplings too can be an issue if using centre buffers with a length of chain you can always have some lengths of chain with an extra link for long vehicles. Chopper type couplings may not couple so easily on sharp curves.

If you can put a short bit of larger curve at the start it willmake a big difference the maximum offset between two long vehicles occurs when one is still on the straight and couple to one on the curve. Obviously if you are daft enough to have a S curve with a sudden change from one tight curve to another the opposite curve that will be even worse a straight bpice between them the length of a coach will avoid the problem.

Don

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