don9f
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Les Warnett 9F, Martin Evans “Jinty”, a part built “Austin 7” and now a part built Springbok B1.
Posts: 960
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Post by don9f on Oct 12, 2020 19:48:52 GMT
Hi, carrying on with the axleboxes, I made the bushes from some SAE660 bronze, leaving the bores slightly undersize for now. Each bush was loctited into its steel box, then a hole was drilled / tapped up through the bottom of the box/bush to form an oil reservoir, with a thin threaded plug to seal the very bottom of the hole. On final assembly, some “bearing felt” will be installed in the reservoir, so as to maintain contact with the axle journal. The drawings show no means of lubricating the tender axleboxes and in the absence of any Don Young written info, I pondered about this for a while and decided to drill / cross drill the axle ends in the familiar manner. The axlebox covers will swing aside like the real things, to expose the axle ends for oiling. Once all this was complete, the axleboxes were refitted one by one into the fixture (still undisturbed in the 4 jaw chuck) for boring the bushes to final size....nominally 9/16” dia. Moving on to the axles, these were prepared from 3/4” dia. bms and as this won’t fit in the spindle of a Myford S7, I used the fixed steady to support them whilst facing and centering their ends....leaving them slightly over length for now. Behind the wheel seat, the axle is nominally 5/8” dia, but with a short larger section of 11/16” dia. for the back of the wheel to butt up to. Having turned the journal and wheel seat to size on one end, I used a collect to hold that end, for turning the other end, aiming for the standard 4 11/16” back to back measurement. The runout at the collett was about half a thou, so I didn’t need to use the “between centres” method, which is what I had originally thought of doing:- The fixed steady was used again to trim the excess length....I originally cut them long to give a bit of a margin in case of a cock-up turning the first end of each axle. Once done, I of course had to re-centre the shortened ends:- Next it was to form the 11/16” shoulder and turn the remainder of the axle to 5/8”. The drawing actually calls for the axles to taper slightly to 9/16” dia. at the middle....something I initially wasn’t go to do as I didn’t really see the point, but then relented and gave one a go.... I chose to have a go at the rear axle, as this is the only one that would normally be just visible on the completed locomotive. I set the tailstock over etc. but to be honest I felt it was straining things a bit much and had to settle for a slightly lesser amount of taper....I definitely didn’t bother with the other two ! Now that I could start to put the axles and boxes into place in the frames, the end float could be set and this involved skimming the “thrust faces” of the axleboxes. To hold them for this operation, I made a simple expanding mandrel which had the added benefit of ensuring that the thrust face was perpendicular to the journal. I only took the one photo of this stage, which shows the thrust face in progress, but unfinished:- However in this photo you can see all the features described so far....bushes, reservoir plugs, thrust faces etc:- Next job will be the unenviable one of fettling the wheel castings (spokes mainly), so that they can then be mounted on their axles. Whilst I do have a couple more days to go, there will unfortunately be an enforced curtailment of activities....if things go as planned....whilst I undergo a knee operation. If they do (Coronavirus things permitting), then I’ll be knobbled for a few weeks and there won’t be anything to update about ! Anyway...Cheers for now Don
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mbrown
Elder Statesman
Posts: 1,720
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Post by mbrown on Oct 12, 2020 20:05:15 GMT
Lovely work Don.
Tricky things, knees. I suspect I'll be facing something similar in due course as I have early-stage osteo-arthritis in both knees. So very best wishes for the op and the convalescence. Hope to see you back in the workshop before too long.
Malcolm
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don9f
Statesman
Les Warnett 9F, Martin Evans “Jinty”, a part built “Austin 7” and now a part built Springbok B1.
Posts: 960
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Post by don9f on Oct 12, 2020 20:49:04 GMT
Hi Malcolm, thank you very much....this is the 4th attempt in over 18 months to have the op on my right knee, the first three postponed for various reasons, by which time the left one is nearly as bad! I’m quite used to knee pain as arthritis started in both of them when I was in my 20’s, over 40 years ago! The last four or five years though have seen a serious decline.
I hope to still follow the various threads and contribute if I have anything of interest....
Don
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timb
Statesman
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Post by timb on Oct 13, 2020 15:18:42 GMT
Hi Don, at the risk of spoiling your thread (apologies) I always get score marks from using fixed steadies, any tips for score free steady use for the malinformed?
Great work!! Tim
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don9f
Statesman
Les Warnett 9F, Martin Evans “Jinty”, a part built “Austin 7” and now a part built Springbok B1.
Posts: 960
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Post by don9f on Oct 13, 2020 19:07:35 GMT
Hi Tim, it is very rare that I use the fixed steady (even more rare for the travelling steady!) and using it recently with these free cutting mild steel axles, I have had no problems at all. It is a genuine Myford steady and the “jaws” look like they are made from phosphor bronze. They were already radiussed about right for the job and I assume it’s fairly important that they are? Are your jaws a bit hard maybe? I made sure they were well oiled whilst the the lathe was running. Today I fettled the wheels, it wasn’t too bad a job but it’s dirty work handling cast iron, made worse by the moulding sand still stuck to the castings....for what they cost, you’d think the supplier would clean them up a bit (no, ludicrous thought)! Some bits of flash on a couple of spokes was really hard and needed the dremel, otherwise a couple of hours filing saw them looking pretty. I chose to loctite the wheels to the axles and the method is to initially turn the wheel seat to approx. 1 thou over the diameter of the reamed hole in the wheel....ie 0.626” in this case. Then the central portion of the seat is reduced by around .006”, leaving a narrow “land” at each end to provide a positive location for the wheel, once it’s pushed on. Before applying loctite 638, the areas were well cleaned with electrical cleaner (isopropyl alcohol):- I also had time today to add a bit of relief to the axlebox hornguides, to allow them to accommodate a bit more “tilt” of the axles in the frames....the drawing didn’t show or mention this, but it was definitely necessary to avoid problems of jamming up. Cheers Don
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Post by ettingtonliam on Oct 13, 2020 20:00:18 GMT
To be honest, its probably best to take delicate castings such as spoked loco wheels unfettled and do them yourself, tedious though it is. I've seen what the foundry fettlers can do, and it can be pretty rough.
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don9f
Statesman
Les Warnett 9F, Martin Evans “Jinty”, a part built “Austin 7” and now a part built Springbok B1.
Posts: 960
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Post by don9f on Oct 15, 2020 18:49:08 GMT
Hi, one more update for now....over the last couple of days I’ve made the “hornstays”, or “framestays”. These are what bolt to either side of the openings in the frames, under the hornguides. In full size, these provide much needed strength to the frames, where they have been weakened by the cutouts for the axleboxes etc.....they also stop the wheels falling out when lifting the engine / tender, or if it gets derailed! Due to the accuracy of the supplied laser cut frames, all six locations required stays the same dimensions. They are a simple milling job from 1/4” square bms....providing one takes into account the problem of distortion that occurs when removing material from just one side! Initially they were made in pairs, just for ease and clamping in the vice etc. A 3/8” slot drill was used to create square cornered slots 7/16” wide, half the depth of the material, 1 1/14” apart....these are the critical dimensions for a good fit over the frames:- Yes there was the inevitable distortion, but when turned over and pressed firmly down onto the parallels whilst tightening the vice, they flattened out again for milling away the recess, this time with a 6mm, 1mm corner radius carbide cutter (the only one I’ve got), to create an illusion of forgings, which is probably what the full size would have been. Once this operation was complete, the distortion mostly “cancelled itself out”! The laser cutting faithfully followed the drawings and a small radius had to be applied to the upper, outer corners of the stay cutouts in order for them to locate in their proper positions, immediately under the hornguides, following which the holes were spotted through from the frames, then drilled for their screws (frames are upside down in the next photo). I’ve still got a few screws / nuts to fit in some of the frame stretchers but it’s good to see a wheeled chassis at last! I’ll have t leave it at that for a while....next job will be making the axlebox spring plates and fitting the dummy leaf springs etc. Cheers for now Don
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don9f
Statesman
Les Warnett 9F, Martin Evans “Jinty”, a part built “Austin 7” and now a part built Springbok B1.
Posts: 960
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Post by don9f on Jan 3, 2021 16:50:52 GMT
Hello again, its been about 3 months since the last update to this thread and some of you may recall that back in mid October, I was about to have a knee replacement. This went ahead as planned and for anyone that doesn't know, its quite a brutal operation and for the first 2 or 3 weeks, I needed crutches to get about and what with all the swelling and aching, didn't really feel like going into the workshop! As things settled down a bit, I did start to make short visits over there to see what I could do....of necessity, mostly sitting on a stool....I made a few of the numerous pins and spacers that were going to be needed on this tender and moved on to making the brake hangers which although laser profiled, needed to be "waisted" down each side, using a fixture similar to the one for the engine described a few months ago. Then it was on to the brake blocks, more pins then the pull rods, both fixed and adjustable, followed by the brake crossbeams (or shafts):- I progressed onto the fabrication of the brake operating shaft (not fitting a steam cylinder on this one), its bearings and the handbrake column . The laser cut frames didn't include the bolt holes for the outer bearings, so using the rotary table, I made a simple drilling jig to enable the 5 holes per side to be accurately drilled relative to the large central hole that was included. The same setup was used to drill the outer bearings. The inner bearings were made by soft soldering bits of gunmetal together, machining as required, drilling holes etc. then heating to separate. After assembly, the mounting holes for these bearings were then spotted through onto what the drawing calls the diaphragm plate:- Next it was to fettle and machine the gunmetal dummy leaf springs. I chose to fit coil springs, within "plungers" working inside the buckles....more pins needed to attach them to the tops of the hangers, plus the spring plates that guide the bottom of the spring plungers, whilst allowing the axleboxes themselves to move around a bit whilst negotiating curves and dips in the track etc:- The axlebox covers are crying out for either castings, or even 3D printed parts, but since I could do neither, I had a go at milling them from some brass flat. The result isn't bad and at least they look something like the real things:- I finished the profiling of the wheeltreads/flanges as well....something I had left until I could spin the wheelsets between centres:- The parts for the tender buffers were simple to make, coordinate drilling the mounting holes carefully to match the laser spotted ones already drilled in the bufferbeam:- Front buffers (still awaiting springs), their "plates" and the drawbar pin:- The tender soleplate is supported by several "pads" each side, themselves attached to angles running the length of the frames on the outside. The "pads" were supplied laser cut and were initially clamped to their marked out positions, then soft soldered into place on the angles. The drilling/fitting of the rivets was done afterwards. I thought this way would produce a more accurate result:- Finally with the soleplate in position, this brings you completely up to date with progress so far:- Next job will be to make a start on the assembly of all the brass tank parts....of which there are quite a lot! Cheers for now and here's looking to 2021 being a bit better for us all ! Don
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don9f
Statesman
Les Warnett 9F, Martin Evans “Jinty”, a part built “Austin 7” and now a part built Springbok B1.
Posts: 960
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Post by don9f on Jan 7, 2021 17:32:19 GMT
As can be seen in the final photo of the previous update, the soleplate already has the cutouts for the “mudguard” shaped covers over the tops of the wheels laser cut, just needing a bit of tidying up of the edges. The tabbed, curved side pieces of these covers are also provided, but the curved top pieces are not, so these were formed from a 15/16” wide strip of 16g brass. To achieve the curve of these, I simply bent them by hand round the 100mm chuck that happened to be on the lathe at the time....once they had sprung back, the curve was just about spot on! I decided to silver solder these assemblies together so that they could subsequently be rivetted into place on the soleplate and caulked with soft solder, without anything falling apart! To hold the side pieces the right distance apart and in line with each other, a simple clamp was made:- A few days ago, I wasn’t really looking forward to this particular job, but it turned out a lot easier than I thought it would, so I’ll get these permanently fitted to the soleplate, then have a think about which parts to tackle next. All the main parts are slotted and tabbed but I have got plenty of 1/4” brass angle to use where needed to make good watertight joints etc. so there’ll be a lot of preparation work before anything else can be permanently fixed! Cheers for now Don
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don9f
Statesman
Les Warnett 9F, Martin Evans “Jinty”, a part built “Austin 7” and now a part built Springbok B1.
Posts: 960
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Post by don9f on Jan 20, 2021 19:35:50 GMT
There is quite a bit of bending / folding of the laser cut brasswork for this tender and as I don’t have a machine for doing that, I made a bespoke bending device....the longest item to bend being the piece for the “well tank” that fits to the bottom of the soleplate. This has a finished length of 14 13/16 inches and is cut from 1.5mm thick CZ108 brass. It bent the shape ok, but as I had marked the position of the bend lines from the outer edges, concentrating on trying to get the height to drawing, I didn’t realise until it was too late that the width was coming out a little oversize! The “development” of the part must include a bit of extra material. Unfortunately it won’t fit between the inner frames as it is, or rather between the numerous screw heads that protrude from them. Also the supplied end plates wouldn’t then be wide enough. In any event, I don’t want to have to take the frames apart to change all these screws to countersunk, so I have ordered a replacement piece to start the well tank again! Next time I shall concentrate on getting the width right, knowing the height will need trimming afterwards. Hopefully I’ll take a photo of the bender in action next time! Whilst waiting for the replacement, I turned my attention to the part that forms the floor of the coal space / roof of the water tank. This is supplied in one piece and once bent to shape, has just two seams that need butt strapping to make a watertight joint. There are more tabs and slots and correct alignment with the upper edges of internal baffle plates meant that this needed very careful bending to make sure everything fitted properly. Thanks to the precision “development” of the laser cut part in the first place, I’m very happy with the result. I bent up a couple of butt straps and rivetted / soldered them in place:- I spent a lot of time thinking how best to attach the sloping sides of the coal space floor plate to the tender sides, wanting to make it strong and easy to seal. Obviously 1/4 x 1/4 angle, as will be used elsewhere would be no good because of the 30 degree downward angle and I eventually decided to use some square brass, machining the required angle along it and mounting the pieces underneath the floor plate and to the tender sides with 8ba brass csk screws....hopefully the photos will make things clear. I don’t have a tilting vice and to machine the 30 degree angle, I found a very simple solution quite by chance..... A piece of 3/4” x 1 1/2” steel supported along one edge by some 1/2” hexagon bar presented an almost perfect 30 degree slope. A 5/16” wide slot was milled along its length, just over half the depth and a tight fit for the square brass. This enabled me to hold it sufficiently rigidly for milling....the vice was well tightened, conveniently holding the steel “across corners”. Again the photo should make sense of this:- This is as far as I got today before breaking my only serviceable 8ba taper tap, so there’ll be another short delay whilst some replacements arrive. Not to worry, there’s plenty of other bits to get on with! Cheers Don
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Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Jan 24, 2021 19:24:18 GMT
Looking good Don! Following with interest-
Gary
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don9f
Statesman
Les Warnett 9F, Martin Evans “Jinty”, a part built “Austin 7” and now a part built Springbok B1.
Posts: 960
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Post by don9f on Jan 29, 2021 19:21:56 GMT
Thanks to the efforts of the new owners of MEL, my replacement piece of brass for the tender well tank arrived today. It had been “lost in transit” for several days due to unexplained courier problems and fortunately, MEL were able to sort it out successfully! Having messed up the bending of the first one, I made sure that this one was marked out so that it wouldn’t come out over-wide. I didn’t mind if it came out slightly under, as that wouldn’t matter. I’d realised after the (over-wide) first attempt that although I’d used 1/2” x 3” flat bms steel for the bender parts, it was still not really strong enough, as bending a 376mm length of the 1.5mm thick brass caused slight deformity of the top clamping plate. The result was a slightly non-uniform bend radius along the length of the material. To combat this I decided that I would add a further clamping screw which would have to pass through the centre of the brass material, but I can either blank the hole off afterwards, or most likely make use of it to install a bush/drain plug. I’m pleased to say that “well tank v2” has turned out much better and once finished, will be very close to the intended 4” width for fitting between the inner frames etc. This is all I’ve managed to do over the last few days, having had our 7 year old granddaughter staying and me being her teacher for her “home schooling”....very time consuming, but equally, very rewarding! Cheers Don
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Post by coniston on Jan 29, 2021 21:24:07 GMT
Neat work Don, that's a nice simple bender as well. For future you could screw / weld a heavy piece of steel angle along the top piece to prevent it bending, or like commercial folders an upturned Vee with a jack screw in the middle applying pressure to the plate?
Agree MEL are doing a great job
Chris D
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Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Jan 29, 2021 23:40:38 GMT
Watching with great interest. I have a very similar job coming up soon with the pannier tanks on Paddington, (about 24 in long!) and only the haziest idea how I’m going to get a straight bend (IYSWIM) over that length without some pretty professional equipment!
(I’m not sure a professional would not be the way to go, if I could find one!)
Gary
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don9f
Statesman
Les Warnett 9F, Martin Evans “Jinty”, a part built “Austin 7” and now a part built Springbok B1.
Posts: 960
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Post by don9f on Jan 29, 2021 23:40:55 GMT
Hi Chris, I did think of screwing a length of rectangular gauge plate I’ve got along the top clamping plate to stiffen it, but when I located it, it wasn’t really long enough. I then thought of the “middle screw” solution, making use of the hole in the brass for a drain point.
Cheers Don
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don9f
Statesman
Les Warnett 9F, Martin Evans “Jinty”, a part built “Austin 7” and now a part built Springbok B1.
Posts: 960
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Post by don9f on Jan 29, 2021 23:58:41 GMT
Hi Gary, years ago I made a “bespoke bender” to form the curved upper & lower edges of the BR Std tender sides for the 9F. I welded some appropriate dia. round bars to the edges of the top flange of a length of sturdy “I” section girder (one was 7/8” dia, the other 1 1/2” dia.). These bars had holes drilled in their ends, to take the pins of two handles, between which a further round bar (another at 1 1/2”dia.) was accurately spaced, just the material thickness away from the fixed bars. I spent 2 or 3 days making this, using a big lathe & welding gear I had access to at the time where I worked. When it came time to do the bending, I was uncertain if it would actually work or not, but the job was done in minutes....it worked a treat!
Let me know if you want further info.....
Cheers Don
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Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Jan 30, 2021 0:41:21 GMT
Hi Gary, years ago I made a “bespoke bender” to form the curved upper & lower edges of the BR Std tender sides for the 9F. I welded some appropriate dia. round bars to the edges of the top flange of a length of sturdy “I” section girder (one was 7/8” dia, the other 1 1/2” dia.). These bars had holes drilled in their ends, to take the pins of two handles, between which a further round bar (another at 1 1/2”dia.) was accurately spaced, just the material thickness away from the fixed bars. I spent 2 or 3 days making this, using a big lathe & welding gear I had access to at the time where I worked. When it came time to do the bending, I was uncertain if it would actually work or not, but the job was done in minutes....it worked a treat! Let me know if you want further info..... Cheers Don Thanks Don, that's very kind. It isn't helped by the radii being 11/16", so the long bars will need to be 1⅜" dia. it's a stock size at least, though not everywhere (and at a price); on the other hand I can't see professional tooling going down that small. Your suggestion does at least offer a solution to build on. I'll have to start giving it some serious thought. Gary
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Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Feb 2, 2021 0:29:14 GMT
Hi Gary, years ago I made a “bespoke bender” to form the curved upper & lower edges of the BR Std tender sides for the 9F. I welded some appropriate dia. round bars to the edges of the top flange of a length of sturdy “I” section girder (one was 7/8” dia, the other 1 1/2” dia.). These bars had holes drilled in their ends, to take the pins of two handles, between which a further round bar (another at 1 1/2”dia.) was accurately spaced, just the material thickness away from the fixed bars. I spent 2 or 3 days making this, using a big lathe & welding gear I had access to at the time where I worked. When it came time to do the bending, I was uncertain if it would actually work or not, but the job was done in minutes....it worked a treat! Let me know if you want further info..... Cheers Don Thanks Don, that's very kind. It isn't helped by the radii being 11/16", so the long bars will need to be 1⅜" dia. it's a stock size at least, though not everywhere (and at a price); on the other hand I can't see professional tooling going down that small. Your suggestion does at least offer a solution to build on. I'll have to start giving it some serious thought. Gary Don, using your setup, would you advise a roller the same diameter as the bend required, or would it better to choose one a touch smaller? Gary
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don9f
Statesman
Les Warnett 9F, Martin Evans “Jinty”, a part built “Austin 7” and now a part built Springbok B1.
Posts: 960
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Post by don9f on Feb 2, 2021 8:04:54 GMT
Hi Gary, there is probably always going to be “some” spring back, but I think I just used round bars of the actual size for simplicity and accepted the small difference in the radius of the finished bends....it wasn’t much. I would think the spring back becomes more of a problem as the radius gets bigger? A few trials/experiments might be required and maybe you could use 1 1/4” dia to achieve the 11/16” radius?
Cheers Don
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Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Feb 2, 2021 11:37:55 GMT
Hi Gary, there is probably always going to be “some” spring back, but I think I just used round bars of the actual size for simplicity and accepted the small difference in the radius of the finished bends....it wasn’t much. I would think the spring back becomes more of a problem as the radius gets bigger? A few trials/experiments might be required and maybe you could use 1 1/4” dia to achieve the 11/16” radius? Cheers Don That’s what I was thinking. On my cab, I annealed the brass before doing any 90 degree bends, and it came out pretty much to size. On the tanks though, Adams specifies 16g material, and I will use brass, and I can’t see any way of annealing that, 24” long or thereabouts, without getting hideous rippling. Or indeed at all; it would need boiler-making kit. There is a substantial framework under the skin, which isn’t strictly necessary. A skilled sheet metal worker would be able to make the tanks as hollow boxes, self-supporting, but I’m not in that league. Given the presence of the frame and ribs, I’m wondering if a lighter skin than 16g would be better, and thus easier to bend. Gary
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