So I plan to recreate a train carrying 5.5" guns headed to/from Otterburn as shown below. This picture is at Reedsmouth Junction on 14th August 1955 going to or from Woodburn for unloading/loading. For this I need a selection of lowmacs ( from the pic you will see that more than one type is present). Currently I plan to do this using the NGS Loriot kit and the Osborns Arch Laser Loriot D kit. My question is, does anyone have any experience/hints/tips on assembling the Arch Laser kit? ( btw - I will use Arrowhead Miniatures for the guns - which should also give needed weight to the wagons ).

Forgive me for asking, but was the Loriot not a "one off" ?

Seems not have been a one off. The Loriot D that Osborns have produce a kit of was one of a batch of 18 ( see  https://www.svrwiki.com/GWR_42138_%27Loriot_D%27_Machinery_Truck ) - and although it might not be one of the exact wagon types pictured, there seem to be a lot of similarities to the first and second complete wagons nearest the camera in the picture. So I think it may make a fair representation.

Then the 3rd complete wagon has some similarity to the NGS kit  which is a Loriot K - that was a "one off" but ( allegedly* ) can represent Loriots of type E, C and D. So reasonable to use a number of them. * I say allegedly since for the Loriot D I cannot quite make the necessary visual leaps between pictured of the Osborn's and NGS kits. However at viewing distance in N it all might turn out to be an acceptable representation. Let's see once i have built this lot....

Ideally of course ( for the location )  I should be looking to build something of more North Eastern origin but the only kit I have seen so far for something of that ilk is a 2mm association etched kit - which could be quite a challenge to build for my skills at their current level.

My results so far as I move towards recreating this train - I have done an initial test build of one wagon and gun - so far unpainted and really I need to paint so as to get a real image of how representative this will be. Hopefully get time to do that soon.

The Osborn's Loriot went together well - it is still unpainted and buffers still to be applied. I think I may need to add brass axle bearing cups to improve the running and adjust the bearing centres as the wheel flanges are touching against the underside of the deck. I am wondering if there is a way to machine down the flanges of these wheels. The Peco spoked wheels do look nice on here so I don't really want to go for something smaller or without spokes. Any ideas?

The 5.4" gun is an Arrowhead Miniatures whitemetal kit and is very well detailed better than expected - assembled with CA (gel type which makes it easier with the tiny parts ) and coated it with primer. There are some slight scale difference issues of 1:152 vs 1:148 that may or may not show up in trying to reproduce the original image. With the Osborn's Loriot this is not so bad as it is a bit longer than the NGS Loriot kit. Also when I need to make a slight adjustment the next kit of the gun I build up - the travelling clamp is represented folded as when the gun is in action and not in the travel position - if it were it would  help in correctly setting the barrel angle when locked for travel - so I think I may have got the angle slightly wrong ( I did check it against a picture of a gun locked for towing and thought I got it right but when I look at the original picture something seems wrong ). I do need to work on how I am going to neatly represent the covers ( tarpaulins ) - probably using tissue paper and "setting" that with paint before putting thin thread on as securing ropes. Thoughts on that helpful as well?

I do need to work on how I am going to neatly represent the covers ( tarpaulins ) - probably using tissue paper and "setting" that with paint before putting thin thread on as securing ropes. Thoughts on that helpful as well?

dilute PVA works well as well and allows moulding with the fingers