Mark

DapolDave, on 21 December 2011 - 12:41 , said: Hi everyone, Another post giving you an update of where we are with the Western with warts and all. As you can see from the cad.cam there are vast improvements to ours now including a full roof detail, better profile front and valance with some tweeks here and there including air tanks, and roof lift rings. Worthy of note, are that the Chinese still cannot understand what an exhaust port is, and that curved roof panels should be exactly that, and that there should not be a gap betwen the peak and the top of the cab front windows!!! However i have a charged cattle prod in my hand and i intend to use it on the engineer. Thanks to Mark for his generous help in aiding this project, and he will no doubt be as pleased as me with some of the progress and vexed by others. Yes you can see a gap betwen the valance and the body, but dont worry as the model will come with spare valances for you to fix and not have a coupling arm gap visible in. And here's a question..............................who thinks we should sell sound equipped DCC ready Westerns using our big speaker and a loc sound4? (just sounding you out (excuse the pun)) Thoughts and questions are as usual welcomed. cheers Dave Hi Dave, I guess the most obvious issues to me at the moment are as follows: Firstly as others have mentioned is the slab sided effect of the cadds geometry. Looking at the roof, it is also possible to see a few straight edges where the roof panels meet the top of the loco, which leads me to suspect that the cadds geometry may actually be correct, but they have used a very low resolution rendering mesh. I guess that is easily resolved by looking at the wireframe edges of the surfaces used. There appear to be a lot of rivets that have appeared on the edge of the roof panels, clearly these should not be there, neither should they be present around the sand box fillers along the lower bodyside. Also it is worth noting at this stage that the window frames are secured with countersunk screws and not rivets. They would be better represented by a slight depression in the surface of the frames rather than a rivet. I notice also that you have used the later pattern battery box door latch on the centre valence. This was a modification that was applied after the Ealing accident in 1973 and therefore would only apply to the last three years of Westerns in service. The original latch was the same as that used on the Warships and would be correct for all livery variations prior to 1974. It is difficult to be sure from the cadds images supplied, but the ledge in front of the windows appears to be parallel with the front windows. This is not the case as it is slightly closer in the centre than on the outer edges. It also follows a subtle curve. The ridge in the middle of the ledge is horizontal, but is sloped slightly down on the outside edges. The start of this slope begins where the plane of the front windows would intersect the side body panels. The cadds images seem to show it starting further back. The other issue regards the bogie suspension box under the body. I see that this has been broken between the body and the bogie presumably to allow for sharp trainset style curves. In reality, this box transfers all the weight of the loco onto the bogie. It rests via rubber blocks onto a leaf spring which is inside the beam outside the middle axle. The leaf spring is then supported by the two pairs of coil springs at each end of the beam. The way I had envisaged doing this on mine was to keep the suspension box and rubber blocks as part of the body and to leave a small gap above the beam in the middle of the bogie. I guess this isn't practical for sharp curves as the coil springs would foul the rubber blocks, but would it be possible to make this part in such a way that it could be fitted either to the body or bogie depending on the requirements of the modeller? Some photo's to help illustrate some of the points above. Shows small gap above front windows before the roof overhang starts Note the gap between the top of the window frame and roof overhang is greater towards the outer edges. Curvature along the front of the ledge on Western Ranger Curvature along the front of the window ledge on Western Campaigner Weight transfer box on Loco into bogie suspension. The block sits on rubber blockes, which are then carried by a leaf spring inside the beams of the bogie. The leaf spring is able to move between the beams and the load is carried by the two coil springs on either side. Each individual axle has two leaf springs behind the frames immediately behind each wheel. Measuring the roof profile. I used a frame which was levelled and then measures the drop of the roof relative to this datum at 3 inch intervals to produce a set of curves through which I could apply a surface. Front view Three quarter view Side view. Early cadds file of mine. Notice the lower part of the cab side doow has an outwardly chamfered lower edge. Regards Mark Humphrys

They are actually countersunk screws that have trapped dirt. The NBL drawings show them as screws. Regards Mark Humphrys

Hi Dave, PM sent with some wheel details. Regards Mark Humphrys

The brake rigging on the Western is below the valence. The problem comes from the front and rear brakes, which foul the valences when the model is on a curve. My own design dealt with this by feathering the back of the valences to provide more clearance without compromising on strength. This resulted in a minumum radius of 5 foot for a P4 Western. Since in OO the bogie frames will be narrower, then 3'6" to 4' should be possible without any need for substantial compromises. Regards Mark Humphrys

That is looking better, but the roof front above the cab is still not quite right. The area around the horn should still follow a curved profile meeting the main roof at a tangent where the first roof panel is located. The cadds model shows a straight line with exagerated curvature at the front. The ledge below the windows should not run parallel to the windows. It is actually slightly curved along the front edge and is closer to the central pillar than the outer edge. The ledge is horizontal in the middle and is only tapered at the out edge, the taper developing as you move away from the centre. The horn cover should be slightly lower at the front than the rear and the engine room vents are still the incorrect shape. See my earlier posting with views of the roof. Looking at the front view, the side skirts appear to be vertical. This is not correct as they taper inwards towards the bottom It is difficult to see from the cadds images, but the nose profile is actually curved in the vertical and axial planes above the headcode panel. This is quite difficult to visualise, so if you wish, I can send you some of my photo's and cadds images illustrating the point. I am not sure looking at the images that the engine room window corner fillets are large enough. The lower part of the cab door should have an outward taper at the base and there is a strip that follows the profile of the top of the door missing. Finally the lower fillet on the body behind the side cab windows is still missing. Otherwise, it is looking very promising in its current state. Regards Mark Humphrys

Hi Dave, The following issues come to my mind in looking at the images. The roof directly over the cab should be the same as the main roof profile until half an inch forward of the panel. It then drops down to the point above the windscreen. The horn shroud seems a little too wide, The roof ventilators are the wrong shape and should be more flat than shown. There is something not quite right about the buffer beam. The gap between the top of the buffer shank and the beading under the nose seems to be too great. It is difficult to see from the images, but the lower part of the nose below the headcode box is vertical. If you need help with the roof, please let me know and you can have a look at the cadds model I have created. I spent a lot of time on the roof of D1010 measuring the profile above the cab and measuring each roof panel. I will post some images for comparison later when I get a chance. In the meantime, there are some images on www.Quality-Diesel-Kits.co.uk (click just to the right of the home button for a gallery of images) The brake pull rods do not run the full length of the bogie as they are part of a linkage mechanism. Regards Mark Humphrys

It dips down sightly, but only on the outer edges. The middle is horizontal. I presume all the lines across the roof panels are just cadds surface boundaries! Regards Mark Humphrys

Looks very promising! My intitial thoughts having only had a brief look concern the roof over the cab, where the droop to the front should start about half an inch forward of the cab roof panel. The cadds geometry seems to be transitioning into the drop too far back. The small roof grills over the opening enging room windows are also able to be opened on the protoype and as such are different to the three banks of grills above the three main bodyside grills at each end, being both longer and different pitched slats. The engine room vents on the roof look to are a little over emphasised as they are raelly not much more than a small square. I think somebody has already pointed out the missing curvature on the front of the nose beneatht the cab windows. The only other area I can see is in the lower valence. There should also be a small ridge on the body at the top of the cab doors following the outline of the door, which is quite distinctive on the prototpe. However, overall impressions are very good at this stage and I know from my own experience how subtle the shape is to achieve correctly on cadds. It certainly captures the look better than the previous efforts have so far. Regards Mark Humphrys

I think Dapol have been talking with Fred Phipps who did the gauge 1 class 22 kit. I spoke to him many years ago and he sent me some copies of his drawings, which are the actual North British engineering drawings and are fully dimensioned that he had tracked down, although they were not the complete set. The positions of grills etc on the body side had to be scaled from photographs. I also found some drawings from the North British collection at Glasgow University, which are only really any good as concept drawings. It is possible to create the wheels, body, roof, and cab windows and all the doors from the engineering drawings. I think the drawings you have Darren are more like weight diagrams than actual detail drawings, based on the image you posted, which shows a tuck in at the lower bodyside more like a Western or Warship than a class 22. Regards Mark Humphrys