This was my first project 5 years ago. The PAA sand hopper wagon. At that point it was guess work, having never even seen one for real, only in photos. So, when I discovered 123D design (now obsolete) I began the drawing... the real wagons are very similar (and based on) the more common PGA wagon and built by WH Davis and Standard Wagon in the 1980’s. For the last few months I’ve had access to one, so thought it time to update my rather inaccurate model with some new design. Here are a few shots of the original and then my art work for the 3D printed “hopper top” to fit to a modified PGA by Hornby. There is still a little compromise, but it gives the overall impression. In the WBB Minerals livery at Cheddleton. The top doors are air operated. Being cleaned up. New ends for the Hornby model New handbrake wheel Measuring the arms Locking mechanism Arm work Ram details Fitting the new ends Drawing up the wagon for fitment (or replicating the Hornby model.) Andy NB3DM
Creating new arm and rams for the top doors. Nearly done. 4 hrs just for the blue parts. Designed to show fitment. Andy
Nice work Andy, I remember these running down the valley in rakes of 15 hauled by a pair of Twenties or a 47, in fact 47 532 was a regular on the sand run and also on Ten Trip to Cauldon.
Well, that’s one of my ideas, but as they were so little modified, with just a change of livery, you can go from build to 2018 and work behind 58,60& 66 for modern day on the Middleton towers trains. Maybe even a 56? Next up will be the single door roof of which there are non left, so it’s a bit of guess work from what I have Andy
So, it would seem that I have come as far as I can in 123D with this model (short of designing the underframe and wheel sets, but the idea was only so I could create parts to fit the Hornby PGA wagon... and at the moment, the cost would far exceed the price of a wagon new! But, finally it’s done. In the closed position.... And the open door position.... It’s still not 100% accurate, some of it has to be adjusted to meet minimum printing thicknesses, but I have to say I’m very happy with this.
Having completed the work on the later PA012B version (that’s the model above with the 2 roof doors) I scratched my head about trying to recreate the original design from WH Davis in Shirebrook, Near Mansfield (the last remaining independent wagon works in the UK!). Now, they appear to have taken the main PGA wagon design by the Standard wagon Company and created a single top door wagon. Non of these survive as they were all converted in a refit to make them all the same as a two door version... frankly, I can see why as it’s a much smaller gap to get your load into the wagon and doesn’t look like there is much strengtg. I don’t know if this is the reason that some ran around with no top doors on prior to the rebuild... but you never know. Now, the wagon we have preserved WBB30025/BIS7954 was built by Davis in around 1983 as a single top door version. It was rebuilt as the 2 door version and ran in this config till the end of their service life in 2018. For a wagon of 35 years of age, it’s in really good fettle. Anyway, I digress. Having made the model of the 2 door it seemed appropriate that we should have a model to represent the unrebuilt version.. I’ve searched high and low until someone posted to me on another group a web link for http://www.barrowmoremrg.co.uk/Prototype.html which I was informed had plans for railway wagons on. After a fair 2 hrs going through each pdf, some with 200 pages in them, I dropped across the PAA 35tonne hopper wagon. Now as this was a British Rail publication it was dated in the 1980’s and by chance carried the original single door version... albeit a very very basic outline but giving some useful dimensions. Having already drawn the top and the wagon body, it was a simple task of working out the new arm positions and “throw” for each arm when the pneumatics pushed them open. Here is the final design (in the open position) as drawn in 123D Design. It varies in that the piston pushes the one door at one end and had the latch at the other, the later version only used one to push from one end for one door and the latch sat along side, and was mirrored at the other. I also had to extend the ladder.. I then imported the model in to Fusion 360... I still struggle with this program... but have managed to add on some artwork. I’m not sure why I have 2 panels that have a red box around them or why the yellow stripe decided to taper off under the ends? But here we have the completed item. I will probably look at a test print after the next pay day and bring you some “model” pictures. Meanwhile, Mr UPS is expected today with the updates print of the first version.
I struggled with Fusion at first but I love it now - can do so much more thand 123. Good effort there though!
Thanks Steve, I think as I have done so much already in 123D its habit and familiarity. When I've over 100 items on Shapeways, its needing a kick up the backside to get me to move over - I probably need to start a new project from scratch, but when I first started on 123D it took me well over 100 hrs on my first project, the signal box, which I could probably do in around 20 now.
Here are the plans I had to work from... Doesn't give you much to go on to be fair.. but its a start. When we went to look at which one to preserve, I managed to get this photo with one of my earlier versions. At Cheddleton, see what I mean about its not too bad even inside... But sand is kind of delicate. The last version of the 2 door - in the closed position. And the prototype with the doors in the open position. It had issues, the side walls were too thin and the doors curved - so I added the bracing as per the real thing. Sadly, it rolled off the desk and broke, so V2 is due in the mail today. That has had some slight beefing up for strength\rigidity. I also made an amendment on how it fits with a .3mm plate on the outside (as per the real thing and missed on this version) that should support the securing points\lower pivots for the door arms.
Sand is very aggressive, hence used on sandpaper, I am amazed the inside of the hopper is not rusty, having had the paint worn out by the sliding sand! I latched onto Barrowmore MRG over a year ago, and added them to my links page, always worth a scan through the categories when looking for suppliers/info sources
I suspect the paint used on those PAA sand hoppers is a two pack epoxy paint. In the olden days when an old banana van was used as a barrier to stop sand blowing into the guards van the silica would have very quickly shot blasted rust off the corrugated ends of the van, particularly so if you were dropping down through Bucknall and Northwood with the wind blowing in the right direction... even as a Class 8 restricted to 35mph. The line speed on the double track from Milton Junction to Pratts was 45mph believe it or not.
I was referring to it being delicate compared to rocks and coal bashing about inside. To be honest, it looks like it’s wel covered in a kind of plastic coat paint.
So, UPS have been today and dropped off V2 of the doors open top. And I have to say, I’m very pleased with this. The doors are stiff, the bracing inside looks good and it fits!! Trail fit! Sadly the white didn’t stand out against the white background. I’ll try again tomorrow with the black back. He also dropped off the N gauge version... This uses the Grafar hopper wagon. New top which just drops in after you flip the coal out. The ends are also a new design and Push in on a pin where the old ones were taken off.. The biggest change on this model is that I’ve had to loose the ladder as it’s too fine to print in N (probably look as good in brass anyway) and create the discharge doors at the bottom. The grafar wagon has pipes and no door bottoms so I had to create these also with the pneumatic rams used to open them (there is some material behind to add strength that won’t be seen) So a productive day all in all.
Briefly tonight... took some more photos pre painting. Shows up better on the black background. You can see the rib detail on the underside of the door. The arm, door lock latch and the pneumatic ram that opens the door has come out well.
Is that the N or OO version? Paint shop probably tomorrow. Let it dry for a few days... It may appear unliveried on the box file layout soon.
In the paint shops. White primer at the moment. Top coat later today. OO scale version. Little and large N gauge version.