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Post by doubletop on Nov 4, 2021 23:54:12 GMT
Model Engineer ran a series of articles by John Smith "Close to scale GWR 14XX in 7.25" gauge" in 2012/13. Polly Model do various parts to John’s design. I’ve never been really happy with the platework that came with my Dart so I ordered the kits back in May.
The parts arrived yesterday and I was pleasantly surprised by the level of detail in the components List of parts Running Boards I ordered a second set of splashers for inside the tanks. Hence the handwritten ammendment in the parts list.
Tanks The tanks sides came pre folded. You dodn't get any bulkheads etc as these need to be made to fit your boiler dimensions
Cab Roof, front and rear panels, windows etc Bunker Tool Boxes So, you can now see why I’ve been interested in the Gary L Paddington Platework project and the recent thread on riveting. (I ordered enough rivets for the job; I was supplied with 3500). I don’t intend to build this completely to John’s design. If I was to do that it would end up more or less impossible to maintain anything without a major strip down. With my current platework the tanks are dry and have 10kg of lead in each side. I can remove the cab and tanks in about 15 mins, they are only held on by 2x4ba bolts, 4x 4ba nuts and 2x6ba bolts. Surprisingly that is enough and I’ve never had any problems. I will probably use more fixings for this job. This is another first for me so where to start is the major question. It will probably be the running boards. However, it may be a while before I produce anything. Pete
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Post by doubletop on Nov 15, 2021 3:22:20 GMT
Not a lot of progress to report. I'm still getting my head around how I amd going to approach this and retain easy access for maintenance. I think I've pretty much got it sorted in my head but in the meantime I've been working on tooling. I've already got a brake/shear/rollor "Formit" as Gary calls it. You will have seen the riveting tools that I posted on the riveting thread. On the Gary L 'Paddington Platework' thread he has made some useful "G"ary clamps so I made myself a set today. After I'd finished them I found his post on page 11 that gives the dimensions. He used 1/2" x 3/4" bar and I used 3/4" x 3/4" so my version wasn't that far off. So much of the work I've got to do is pretty much the same as Gary has already posted so I will just about follow his lead. Pete
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Post by doubletop on Nov 22, 2021 9:14:57 GMT
Well, I’ve made a start. For ease of maintenance, I plan to make six sub-assemblies. - Left and right hanging bars with the front corner, leading wheel and tank running plates permanently attached. - Left and right tanks with separate tank floors, the floors will be bushed to allow fixing bolts up through the tank running plates. I’m doing it this way because the thought of having to remove 27 8ba rivet bolts every time I want to take the tanks off doesn’t appeal. As I’ve said before these tanks will be dry and hold 10Kg of lead in each. - Bunker fixed to the bunker running plate and the plate bolted to the hanging bars with 8 x 8ba hex bolts the others bolt holes will be filled by dummy rivets. The lower bunker will contain a small cross tank for the injectors. This is/will be supplied by a tank in the driving trolley. - Cab roof and spectacle plate, bolted to the two tanks and bunker with 10ba bolts rather than riveted. This will mean the cab roof can easily be removed and then the two tanks removed for maintenance. Something I do after every run. On to progress……Splashers have been silver soldered. You’ll notice the three screws holding it together. The side plate comes with a ridge removed for the top to fit. By rolling the top just a tad more that required it clips into place in the groove and the screws just hold it there. In place on the leading wheel plate. You’ll notice that the holes in the surround don’t match the holes in the plate. It looks like a bit of an error here on the kit. Not much of a problem to re-drill to match the surround. Really the first thing that needs doing is the hanging bars as this is really the interface between the old and the new. Once these are done and the running plates attached then every thing else builds off the running plates. The front and rear hanging bar end plates are pretty much to John Smiths drawing but the brackets need to be made to attach them to the Martin Evans buffer beams. The first concern was that dimensions of the outer face of the frames. Martin Evans 6.0625” inner dimension with 3/16” thick frames, John Smith 6.033” inner dimension and 5mm frames. Overall Martin Evans is 0.0107” wider so nothing worth worrying about. The length is pretty similar also, the overhang of the running plates on the buffer beams is adequate. The next thing was to drill the hanging bars to the hole pattern in the plates. As I have DRO’s on my mill I prefer not to spot through and drill. Rather than just pitch in and use the dimensions in John Smiths drawings I thought I’d better check. Good job I did, the hole spacing on running plates are not to the drawings. For each plate the same number of rivet holes are provided over the same distance but they are equally spaced. No doubt easy for the CAD. Other than nealy catching me out it is not a concern for me. I did need to work out where the holes landed laterally on the hanging bars. I used the bunker plate as a reference as it provided the dimension between the mounting holes. The plate is 12.375” the inner face of the hanging bars is 11.875”. Therefore the holes need to be 0.25” from the inner face of the hanging bar. Armed with this info and a table I created of the hole spacing along the hanging bar I drilled and tapped the first 38 holes. To discover, as per drawing, the offset from the edge of each running plate to the line of holes is different for each plate Front Corner and Leading Wheel plate 5/32" Tank Plate 3/16" Bunker Plate 7/32" Therefore 0.25” was incorrect for the other plates. Tomorrow’s job is a new hanging bar. Fortunately, I’d only done one. Pete
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JonL
Elder Statesman
WWSME (Wiltshire)
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Post by JonL on Nov 22, 2021 15:19:23 GMT
Looking good, following with interest. That mild setback shouldn't hold you up I imagine.
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Gary L
Elder Statesman
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Post by Gary L on Nov 22, 2021 21:21:42 GMT
Well, I’ve made a start... [Snip] The next thing was to drill the hanging bars to the hole pattern in the plates. As I have DRO’s on my mill I prefer not to spot through and drill. Rather than just pitch in and use the dimensions in John Smiths drawings I thought I’d better check. Good job I did, the hole spacing on running plates are not to the drawings. For each plate the same number of rivet holes are provided over the same distance but they are equally spaced. No doubt easy for the CAD. Other than nealy catching me out it is not a concern for me. I did need to work out where the holes landed laterally on the hanging bars. I used the bunker plate as a reference as it provided the dimension between the mounting holes. The plate is 12.375” the inner face of the hanging bars is 11.875”. Therefore the holes need to be 0.25” from the inner face of the hanging bar. Armed with this info and a table I created of the hole spacing along the hanging bar I drilled and tapped the first 38 holes. To discover, as per drawing, the offset from the edge of each running plate to the line of holes is different for each plate Front Corner and Leading Wheel plate 5/32" Tank Plate 3/16" Bunker Plate 7/32" Therefore 0.25” was incorrect for the other plates. Tomorrow’s job is a new hanging bar. Fortunately, I’d only done one. Pete Hi Pete very annoying, but not fatal I hope, even coming so near the start of your work. Commiserations; it seems to be an occupational hazard working from loco drawings (and I've done it on my own drawings, so I can't be 'holier than thou.' Is the different rivet spacing a feature copied from the prototype do you suppose, or is it an error on the part of the draughtsman? Gary
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Post by doubletop on Nov 23, 2021 7:50:57 GMT
Hi Pete very annoying, but not fatal I hope, even coming so near the start of your work. Commiserations; it seems to be an occupational hazard working from loco drawings (and I've done it on my own drawings, so I can't be 'holier than thou.' Is the different rivet spacing a feature copied from the prototype do you suppose, or is it an error on the part of the draughtsman? Gary Gary Not a major problem to re-make the hanging bar all done and both sides now drilled and tapped, something like 78 holes all 8Ba. The original drawing John Smith had done he'd tried to get as much as possible to the prototype so, for example his drawing for the tanks have 25 holes over 19.0625" the front 4 at 0.781" spacing and the remainder at 0.797" spacing (1/64" difference). The kit has all the holes equally spaced at 0.794" spacing. As far as I'm concerned very pragmatic and who is going to notice? In my last post I had quoted the distance of the line of holes from the edge of the paltes but something didn't sit right with me and I checked again. Good job I did in fact the correct values are Front Corner and Leading Wheel plate 7/32" Tank Plate 3/16" Bunker Plate 7/32" Another cockup averted. Although when I was drilling the 78 holes I was still doubting myself and wasn't convinced I had it right. Thankfully it was. No update pictures yet and plenty more to do in with the running plates before moving onto tanks, bunker and roof. Pete
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Post by doubletop on Nov 23, 2021 22:23:44 GMT
I've let Matthew Thomas from Polly know and althpugh they have sold a number of these kits he was unaware of this difference between the kit and the drawings.
He tells me has already updated their CAD files to the drawings so any future kits will be produced as drawn.
Pete
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dscott
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Post by dscott on Nov 23, 2021 23:06:11 GMT
I've let Matthew Thomas from Polly know and althpugh they have sold a number of these kits he was unaware of this difference between the kit and the drawings. He tells me has already updated their CAD files to the drawings so any future kits will be produced as drawn. Pete We or more importantly I did a sort of Supermarket sweep at Polys several years ago and had to hide the checkout total from Lily at the exit. A lovely tour. Thank you Matthew. Wonderfully with modern storage and printing when needed. Poly do not have a stock of drawings on shelves getting dusty full of mistakes? When you order drawings from them the updated file is accessed and printed for you. I was incredibly impressed by the set of Jessie drawings that arrived all rolled up. Just superb if you want to frame the general arrangement on your bedroom wall. David and Lily.
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Post by doubletop on Nov 25, 2021 22:08:46 GMT
That is all the running plates and bunker floor now located a temporarily fixed to the hanging bar. It is all a remarkably good fit, particularly when you realise the frames were made many years ago and I'm the third owner. Other than making the hanging bar ends match the Martin Evans design of the buffer beams and ensuring that the holes for the plates were correctly located on the hanging bar little fettling was required to get it all to line up. Next is various plates to join the three front running plates together and fixing to the frame outriggers. Then the 4 steps. As I've said before the running plates are not going to be removed individually, along with the hanging bar and ends they will form one sub-assembly. The bunker floor, with the rest of the bunker, will become another sub-assembly. Something that could possibly go wrong is the way I plan to do the tanks. These strips are intended to be folded and the side with the larger holes goes into the running plate with 28 x 8BA slotless rivet bolts and the side with the smaller holes riveted to the tanks. From a maintainability point of view that just isn't going to happen. I'm going to split these strips down the fold line and fit one half to the running plate and the other to the tanks. I'm hoping that both faces will butt up to each other sufficiently that the gap isn't too noticeable. The tanks will have separate bases and 4 bolts through the running plate to hold them in place.
Pete
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dscott
Elder Statesman
Posts: 2,437
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Post by dscott on Nov 25, 2021 23:38:34 GMT
Great idea. This is what takes the time with these models.
Lovely story so sit down and enjoy. A new Pansy and owner arrived at the track with various bits not working including the hand pump in the bunker. "Hours spent!" he moaned. And everyone busy. he turned to me and asked for help. 4 under the bunker and 2 into the roof screws taken off and the bunker lifts off. New O ring fitted to the ram and it worked superbly. He and I had lovely drives all afternoon.
David and Lily.
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Post by doubletop on Nov 26, 2021 9:01:38 GMT
Great idea. This is what takes the time with these models. Lovely story so sit down and enjoy. A new Pansy and owner arrived at the track with various bits not working including the hand pump in the bunker. "Hours spent!" he moaned. And everyone busy. he turned to me and asked for help. 4 under the bunker and 2 into the roof screws taken off and the bunker lifts off. New O ring fitted to the ram and it worked superbly. He and I had lovely drives all afternoon. David and Lily. That is the plan. The cab roof and tanks will be able to be taken off in 15 mins and back on in a similar time. If any more is required the bunker assembly will be just as easy to remove but a bit of plumbing will need to be disconnected. Two water feeds for the injectors and the input from the driving trolley. With all the plumbing disconnected from the boiler and the blow downs removed the boiler can be removed. Currently, to get to this point from a runnable loco takes about an hour. With the cab roof, tanks and bunker removed the running plate assemblies will also come off just as easily. When you get to this point the motion, which is between the frames, is as accessible as its ever going to be. You would never be able to do this if the kit was assembled as drawn. Pete
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nonort
Part of the e-furniture
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Post by nonort on Nov 26, 2021 13:09:53 GMT
A bit of a wild thought! Why not use indium magnets to hold the tanks on? I know of two seven and a quarter engines with this approach. you can even oil up with out having to have bent oil cans.
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Post by doubletop on Nov 26, 2021 18:53:45 GMT
A bit of a wild thought! Why not use indium magnets to hold the tanks on? I know of two seven and a quarter engines with this approach. you can even oil up with out having to have bent oil cans. I think I'll continue with 4 bolts. There will be 10kg of lead ballast in each tank and I'd hate the thought of the magnets coming unstuck at an inappropriate moment. Pete
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Post by doubletop on Nov 27, 2021 4:42:56 GMT
I thought it was time to bite the bullet and attempt to split these tank angles. I was cautious as any stuff up would mean potentially a long wait for Polly Model to make me some replacements or the prospect of having to drill lots of holes. Fortunately I found I had a 0.015” slitting saw but it needed an arbour that would clear the vice. So, first job today was making an arbour. With the job supported my most appropriate parallels the clearance with the top of the vice was only 10thou so I resorted to jacking the job up slightly on a piece to 1/16” TIG rod. The thickness of the strips is only 1.2mm so they were bolted together to get the job closer to the 3mm thickness of my parallels. This still needed a packer to be able to clamp them in the vice. The job then sat on one parallel with a 1/16” TIG rod underneath to lift it and a packer sat on a second parallel The job is about 20” long so about 5” were done at a time and then moved along. You can just about see the slit here, along the line of the grove Polly Model included for folding. The engineers clamps stopped the cut ends of the job resonating and also stopped the slit from closing up on the saw. The test to see if this approach is going to work. I think that is going to be pretty acceptable. When full assembled ant gap between the two will be barely noticeable Pete
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Post by doubletop on Dec 5, 2021 9:04:48 GMT
Now that I know my approach to making the tanks removable is going to work, I started making the components for the tank internals. I didn’t get very far before I realised that working directly from John Smith drawings wasn’t going to be practical. There’s nothing wrong with John’s drawings (well there as few things I’ve found so far) but those of you who remember them from the ME articles will know they are very detailed, and 60+ sheets. So detailed it can be hard to find the dimension you need, and may have to find a complimentary dimension on another sheet. That coupled with numerous dimensions in 64ths of an inch there is plenty of scope for error. Then there are the hundreds of holes to be drilled in the new parts. I made the decision that spending a bit of time on the CAD will pay for itself in the long run. I’m not that I'm adept with Fusion 360 so the hour or two turned into the whole weekend. I am getting better at it. The tank kit only comes with the tank sides, tops and I purchased an extra set of splashers. That means the rest has to be made. You can see the number of bulkheads, and the associated angle brackets for each, plus a number of other parts. As you can also see lots of holes. I may well not do them all and just use dummy rivets for some, but I’ve drawn just about all of them and I can decide when it comes to doing the job. I had asked Matthew at Polly why they didn’t do the tank internals in the kit and was told that the problem is not knowing the size of the individual boilers. If the Belpaire cladding is too thick then the spectacle plate will need modifying to fit and possibly the tank tops will need trimming slightly, that would mean an amendment to the bulkhead widths and associated brackets. I can see why they don’t do it. Fortunately, I will only need to adjust the spectacle plate slightly as there is about 0.22” difference between the width of the spectacle plate opening and the width between the tank tops. As I’m making this so the tanks can be removed, I can’t follow John’s drawing and put the reverser on top of the right-hand tank. I intend to use the Martin Evans reverser, well the standard at least. You can see from the drawing that will work pretty well. On the other side is the lever for the drain cocks. That will need a bit of modifying. Although the front of the tanks will have their own floors, separate from the running plates, the back of the tanks won’t. That will allow me to lift off the tanks and mount any non-standard gubbins on the running plate, under the tank body. On the right that could well be a battery for the loco lamps, or in my case the electronics for the boiler pressure and temperature sensors that are part of the data logger on my dynamometer. For the left-hand tank, it will be the valve for the steam operated drain cocks. So, it is looking more and more like my approach is going to work. Pretty soon I’ll be able to call myself a rivet counter. Rivet Count To Date = 0.Pete
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jwkb23
Active Member
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Post by jwkb23 on Dec 8, 2021 21:44:46 GMT
Pete, I am very jealous; I ordered my kit in March and am still waiting for it.
Hopefully it will arrive before Christmas !
James
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Post by doubletop on Dec 12, 2021 6:33:09 GMT
Pete, I am very jealous; I ordered my kit in March and am still waiting for it. Hopefully it will arrive before Christmas ! James James That is very interesting. Although I started the discussions with them in March clarifying a few things, I didn't confirm the order until mid-May and then paid the deposit. With no intention of knocking Polly in anyway their processes do seem to be lacking somewhat. Orders don't get confirmed and shipping information needs to be sought rather than automatically supplied. I found my shipment was on its way when DHL got in touch regarding customs clearance. Fortunately, it took less than a week to get to NZ. I'd be inclined to call them. It would seem strange that they had more than one order to deliver and not manufacture them both at the same time. Hopefully it is in hand and when the kit arrives, you'll be pleasantly surprised. The catalogue description doesn't do it justice. Pete
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Post by doubletop on Dec 12, 2021 7:21:10 GMT
Having spent last weekend drawing parts for the tanks I was able to get things underway during the week. First was all the angles etc for the tank bulkheads and top and bottom. Then it was time to bite the bullet and try this riveting lark. Doing something I’ve never done before is one of the reasons for doing this project. As I said before, rather than use the running plates as the tank bottom I’m doing the bottoms separately. As the rivet holes for the bottom angles are only 1/8” from the bottom of the tank sides it means that 1/4“ angle couldn’t be used as it would need to be inset 1/16” to accommodate the bottom plate. Therefore I’ve used 1/4“ square bar for the bottom rails. The keen eyed amongst you will spot some rivets that could have been done better, but I took the view that attempting to get them out and re-do them was likely to be create a bigger problem than letting them be. What is more the problem was due to the rivet shanks being too long. Something that was only noticeable on the inside of the tanks so i could be a good few years before anybody else discovers them. I do have some “smiles”, along with some scratches, on the front face of the platework. The scratches occurred on the trip to New Zealand. I don’t consider them a problem at all. Once completed the tanks will be blasted with fine grit in preparation for painting. All these minor blemishes will easily disappear. The rivet length issue was quickly remedied with a modification to my rivet chopper to obtain the correct lengths, I was then able to carry on and produce some nice regular rivet closures. It will now trim 1/32“, 3/64” and 1/16” rivets from 1/4“ down to 3/32” in 1/32” increments Chopping the rivets down is probably the longest part of the riveting task. Installing the trimmed rivets and forming with the rivet pliers is relatively quick. You may notice that the chopper is being used by pushing the lever away from you. Not a design feature but I have inadvertently made myself a left-handed rivet chopper. The stepped holes should really have been on the right-hand side of the plate. That’s it so far. Next task is the bulkhead plates. Rivet Count To Date = 480.Pete P.S. The bottom rails aren't fully riveted as I waiting for some longer rivets from Polly. (That reminds me I do need to follow up on that order)
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jwkb23
Active Member
Posts: 18
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Post by jwkb23 on Dec 16, 2021 7:29:53 GMT
Pete, I am very jealous; I ordered my kit in March and am still waiting for it. Hopefully it will arrive before Christmas ! James James That is very interesting. Although I started the discussions with them in March clarifying a few things, I didn't confirm the order until mid-May and then paid the deposit. With no intention of knocking Polly in anyway their processes do seem to be lacking somewhat. Orders don't get confirmed and shipping information needs to be sought rather than automatically supplied. I found my shipment was on its way when DHL got in touch regarding customs clearance. Fortunately, it took less than a week to get to NZ. I'd be inclined to call them. It would seem strange that they had more than one order to deliver and not manufacture them both at the same time. Hopefully it is in hand and when the kit arrives, you'll be pleasantly surprised. The catalogue description doesn't do it justice. Pete It must be magic but the day after mentioning it on here my parcel arrived from Polly! Does anyone have a suggestion on where to get copies of the construction articles in Model Engineer Magazine from?
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Post by doubletop on Dec 16, 2021 7:58:08 GMT
James That is very interesting. Although I started the discussions with them in March clarifying a few things, I didn't confirm the order until mid-May and then paid the deposit. With no intention of knocking Polly in anyway their processes do seem to be lacking somewhat. Orders don't get confirmed and shipping information needs to be sought rather than automatically supplied. I found my shipment was on its way when DHL got in touch regarding customs clearance. Fortunately, it took less than a week to get to NZ. I'd be inclined to call them. It would seem strange that they had more than one order to deliver and not manufacture them both at the same time. Hopefully it is in hand and when the kit arrives, you'll be pleasantly surprised. The catalogue description doesn't do it justice. Pete It must be magic but the day after mentioning it on here my parcel arrived from Polly! Does anyone have a suggestion on where to get copies of the construction articles in Model Engineer Magazine from? That is good news. Somebody to compare notes with. If you have not done so I'd suggest you get a copy of the drawings from Polly. Even if you are only doing the platework money well spent otherwise you'll be scratching your head at times. I've already found a couple of errors in the drawings but that is all part of the fun. Pete
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