Ray H

My dcc controlled O gauge layout represents a fictious Light Railway primarily because of the relatively small radii needed to fit it into the garage. I've invested in a few 0-6-0Ts in the hope that they might not be too picky about power collection where the track takes a bit more effort to reach/clean. Two of the locos are Dapol Terriers, one - Bodiam - in blue (and numbered 3), the other - Portishead - is in green. I also have an unnamed Manning Wardle also in blue. I'm minded to retain the blue locos as they are, and adopt a similar shade (of one or other) as part of the railway's colour scheme. My question relates to the green loco (and any other non-blue ones that I may get). Is there likely to be a significant impact on the value of an R-T-R loco that has its colour (and optionally number and/or name) changed assuming there's been a good quality (re)paint job?

The two Drop-In-Sections (DIS) have now been ballasted. However, I managed to miss a few areas and had to apply some more ballast (and adhesive) in a several places. The smaller (Light Railway) DIS was ballasted several days ago and had been test fitted in place a few days later, only requiring minimal “cutting back” where some of the ballast had managed to project slightly over the ends of both the DIS and where the track ends on the fixed boards. The larger DIS was only ballasted at the beginning of this week and still wasn’t completely dry 3 days later. This DIS (and the part of the fixed boards where it aligns) had also suffered a bit of ballast creep that I think I’ve now attended to but it’ll take a few train movements over it (and a few insertions and removals) before I can be sure. Readers may recall that I added some blocks to the underside of the DISs which aligned with the track on the fixed part of the layout on which the DIS rest stand when the layout’s not in use - said blocks are just visible in the above pictures. It appears that I didn’t check that the blocks on the larger DIS (whilst aligning nicely with the track they’ll stand on) were actually clear of the fixed parts of the baseboards when in position for trains to run over ☹. Fortunately, I only fixed each block with a single screw so I was able to “unscrew” the errant block, drill a new hole and insert the fixing screw through the DIS before screwing the block back on where it is clear of the fixed baseboard.. I’d been thinking about 3D printing on and off for a while, more recently for its use for making the windows in the factory at Mixbury. A few other ideas surfaced from time to time but the trump card so to speak was to be its use for printing the girder parts for the sides of the DISs (once I’d experimented with using it (and coming to terms with the 3D software) for some easier things). Regular readers of these pages will know that the LR “bridge” over the lower-level tracks at the far end of the garage had utilised the Scalescenes prints enlarged to size suitable for O gauge. Once I’d worked out how to print them, I’d use the components for the DISs and to replace the paper ones on the existing bridge. I’d even worked out roughly how the printed parts would fit together. Browsing through my copy of “Bridges for Modellers” by L. V. Wood to see what I might need to print; I came upon this picture of the flyover at Rugby which got me thinking. A girder bridge (without intermediate supports), the length of the DISs, especially the longer one, might look better than the plywood sides of the DIS, but would probably be beyond the realms of even modern-day technology. However, here is pictorial evidence of multiple short span arches used to support a bridge that could be of any length. I could limit the height (between ground level and the underside of the DIS) to match the height of the aforementioned blocks (that support the DIS when not in use) and have a false ground level on which the arches stand that probably need only be unkempt ground. What’s not clear from the picture of Rugby is whether the arches pass right through to the other side of the structure or whether the openings are fairly shallow. Does anyone know?

Sorry, my reference to 11 pins should have read 11 wires.

Could 11 pins be the usual 8 plus 2 for the speaker (or stay alive) and the brown wire whish is often longer than all the others?

The next task has ended up being the ballasting of the longer but narrower of the two DISs. I also took the opportunity to repopulate the areas of missing ballast in and around the area that plays host to said DIS (and the LR tracks). The lifting access flap has still to be dismantled as I seem to have found numerous other things to keep me out of the garage recently. I am hoping to ballast the other DIS tomorrow, once today's effort is dry. I hope to do it without tipping over the jar containing the diluted PVA like I did today 😒

Is the new bridge one that will be slewed over as a replacement for the existing one?

I believe at one time (and it may still be the case) that around 07.00 SX there were trains from Ipswich to Liverpool Street departing in opposite directions (and using different routes to London).

Some of what I'm hoping to print is liable to find itself on the garden section of a colleagues O gauge layout. Has anyone any experience of a similar usage/requirement with indications of a good resin, water based if possible? Thanks.

The picture or Mavis?

I have managed to do a little more to the layout now that I seem to have gotten over at least some of my initial teething problems with the 3D printer. The first of the two (new) drop in sections (DISs) was held in place with very crude home made bolts and some locating pins. Following the success with the up-market home made bolts fitted to the 2nd (larger) DIS, I upgraded the bolts on the first DIS yesterday and have removed the now redundant locating pins. Some trial running with a light engine showed a slight "hump" at one end of the rejuvenated DIS. Some judicious packing under the track on the DIS in that area has solved that problem. As previously mentioned, the DISs will sit on the trackbed when not in use. This has an upside and a down side. The upside is that in this position the DIS prevent any runaways taking a dive to the floor off the end of the baseboard. The downside (?) is that whatever (minimal) scenery there is in those areas would have to stay below rail height. Whilst my dislike for undertaking scenic related tasks is well known (by mean at least), limiting the height to such a low profile is probably unrealistic. As a result I plan to fit some blocks to the underside of each DIS. These blocks will be in-line with the track upon which the DIS sits when not in use. It is easier to fit the blocks before I ballast the DIS as the securing screw can be be buried under said ballast. I think it is now safe to dismantle the old lifting access flap, which will be one of the next tasks.

I believe there is a Zimo decoder CV that determines how long a loco/motor should run on for if track power is lost. This may be set to a (very) low value on 7800 and may account for the difference. Are the two capacitors of a similar rating? You should be looking for a number followed by µF or uF. The higher the better (within reason).

I had seen the auto arrange option in Chitubox but hadn't understood its purpose, so thanks for that. And to continue the saga . . . . The computer has indeed arrived. It came with a power lead and what looks like a wireless Internet dongle but the monitor was absent as were the keyboard and mouse. Unfortunately my present monitor has a 15 pin VGA style connector whereas the new box of tricks has a connector - USB? HDMI? - that I've not aware of seeing before. I have been promised delivery of the remainder of the kit by Friday. I do have myself partly to blame because I ordered the various items over three days but I'm told the monitor I was to have had failed during testing hence the delay. Anyway, back to the Mars 3 Pro. I thought I'd nailed it with the more flexible build plate but No! Probably my fault because in my hurry to try it, I overlooked to give the flexiplate a clean, just using it straight from the packet. I did get three out of the ten models printed but the bottom layers (and little else) for the remaining seven were stuck to the FEP. I cleaned the flexiplate - which I've just discovered has some fairly sharp edges that I need to attend to - and increased the bottom layer exposure time back up to 30 seconds. Just under two hours later I had ten models, all of which look to be complete prints. They've just been removed - quite easily - from the flexiplate and have been through the wash machine. They'll go through the curer in the morning. Fingers crossed, I think I might now have a better understanding of this 3D printing lark. Thanks for all the responses & suggestions. Can I suggest for those who don't know about it, search YouTube for videos on the use of the Tank Cleaner facility. It's saved me having to keep draining the tank. I've got some work I want to do on the layout over the next day or so, so I'll probably give the printer a rest until after I get the new computer up and running.

The Modelu .stl file does come with a raft. I think I just got carried away yesterday for some reason. I'm fairly certain that I saved the finished item (all ten models) using Save Project before I started the print but I can't find that file now so I'll recreate it without the extra supports and try reprinting. The mirrored version of yesterday's half model printed OK so maybe the half model struck unlucky. I think that might have been the one near the marks under the FEP. Thanks for the tip about the right mouse button. I've just tried it but it seemed to take a while for the display to respond. The replacement PC is due later today, thank goodness. The flexiplate is a story in itself. Intent on taking full advantage of my month's free Prime membership which I got when buying the Mars 3, I looked for the flexiplate thereon and found what I thought was a complete set. When I opened it I somehow thought the metal plate I found was the magnetic part with the adhesive "stuff" on the other side so I went shopping again elsewhere and bought what I thought was just the magnetic flexiplate. Imagine my surprise when I eventually discovered that the second purchase wasn't actually needed - the metal plate that I found in what I'd bought originally was the flexiplate and the adhesive side incorporated the required metal plate to affix to the build plate. Doh! The removable plate that I'm currently using doesn't seem too flexible - it does bend with some force but so far its only managed to cast a few models off. Your post has just encouraged me to check all the other plates that I bought. Lo and behold, the plates of two of the unused three sets are a lot more flexible so I've changed over to one of them. All good "clean" fun. Expect a pause in developments whilst I sort the computers out.

I decided to have another go late yesterday afternoon, this time with some of Modelu's seated people. Five as supplied and five as mirrors of the supplied five to give ten in total. There were no other changes other than the mirroring so if one model printed and its mirror didn't I could tell whether or not there might be a problem with the model's supports. I'd let Chitubox add supports below the Modelu base and also add a few other supports that it felt needed. The Bottom Exposure was set to 25 seconds and the normal exposure set at 3 seconds One of the ten models was nowhere to be seen once the print had finished and another was only printed from the waist down and ended up waist down stuck to the FEP. The other eight look OK although I haven't inspected them too closely yet. The (Chitubox added) bottoms were a swine to remove from the build plate. Luckily, I was able to remove the models themselves from the Chitubox supports so the models escaped damage. I'm going to try a slightly shorted bottom exposure, perhaps 22 seconds next time. I did notice that I could see a mark on the underside of the FEP/top of the screen when I was removing the half model. My guess is that the IPA hadn't completely dried when I refitted the tank. That may account for the problem with one of the models. The missing model maybe attributable to it not being sat on Chitubox's "build" mat which I'll check later. Trying to squeeze all ten models onto the "build" mat wasn't the easiest thing and I may well have lifted the missing model when I meant to move it sideways, but that's just a guess. I plan to rotate the print horizontally through 180º prior to the next print as another means of checking that I'm heading in the right direction. An advantage of seated passenger models is they aren't so tall, so the print finishes quicker🙂

It does look as though the straight blade isn't sitting snuggly against the curved stock rail when the point is set for the straight - the apparent step where the other end of the straight blade meets the closure rail - the rail leading towards the frog - isn't smooth has already been mentioned. Is there any chance that you make a slight revision to the layout? Could you replace the left hand point with a right hand point that takes the place of half(?) of the last curved section? Alternately, could you move the point towards the point at the other end of the loop and insert a straight length between the end of the curve and the point's new position. You would lose some of the length of the loop but it might go a long way towards eliminating the derailments.

Are all the derailments at the same place on the point. Can you locate/identify that position.

Check one of the wires hasn't come out of the ferrule.

Did you discover what was ailing the Class 37 yesterday?

The bottom one is 35 seconds and the ordinary is 2.5 seconds.

Thanks for the latest responses. I believe that I have now set a new printer profile or, at least, changed from the Default printer to the Elegoo Mars 3 (and deleted the Default printer). I can't remember whether I've always used the Default printer or whether it got changed at some stage although I don't recall ever changing it. As yet, I haven't had time to do a test print but intend to do that later this morning and report back.

Other commitments have had priority this morning which was probably a good job because no matter what I tried to do earlier, the machine wouldn't recognise the files that I was trying to print. That said, I've just noticed from the icons on the machine's screen that either the computer itself, Chitubox or the memory sticks I'm using - not the one that came with the printer - are misbehaving. Something must be amiss as the file I produced with multiple scaled down rooks is only showing with a file size of 1,211KB. The memory stick to which the file has been written still has over 13.5GB space so it isn't a disk space problem. I'm half inclined to see either if my Chitubox program itself offers an update (for the free version) option or whether their website has an updated version available. This PC has only a few days left to live (hopefully) but it might be worth uninstalling the program and then trying again. Heaven knows how the program arrived at the .cbddlp file extension.

Thanks for all the ongoing suggestions and comments. I was wondering whether trying to test print something that is spread reasonably evenly across the build plate - something like numerous rings of "plastic" of say an 15mm diameter and perhaps 10mm high might be worth the effort. I haven't tried printing the Elegoo rook so multiples of that reduced in scale could be a better test. The printer hasn't been moved since I first used it and several of my initial prints came out fine but I'll try a spirit level on the machine before the next print. The printer is in a spare bedroom. The ambient indoor temperature currently is a little over 21ºC. Is that high enough & how do you keep the resin's temperature up once it is in the tank. Is simply having the machine on for a (continuous) period OK? Can you get/do I need a tank heater? I've given the resin a good shake each time before putting it in the tank. This generates a number of small air bubbles in the top of the resin once it is in the tank. I've tried to push them aside before I start printing. Do they matter? Your reference to resin calibration tests and print speed are new terms to me. I've just googled "resin calibration test" and will give that a go. Would it be necessary each time you change resin or should resins from the same supplier where only the colour varies be the same? Another dumb question - how do you set the print speed? Is that the same as the lift speed?

I think he means catenary although it might be after the next centenary before he starts - he's younger than me so might still be around by then 😄

The most recent print (after the aforementioned bolt tightening) was of four models (of people). One was successful, two had their supports on the build plate plus the lower parts of their bodies affixed to the FEP. The fourth only appears to have managed the supports - I have yet to drain the tank to check the FEP is clear. I've checked the settings that I'm currently using with those on the Chitubox website. The only significant difference that I've found is the exposure time 6s (Chitubox) above and 30s (mine) below. I've no idea where the 30 seconds exposure time has come from and if that is the time between each layer's print I'm certain that it is nowhere near that value when printing. I'll reset the 50s to the 6s suggested and have another go either tomorrow or Monday. Is my Lifting Distance setting of 6mm against the default setting of 5mm likely to make any difference?

The build plate securing bolts weren't fully tight. That's been corrected and I'm running another different print. I reverted to the black resin for the previous file I printed - the one that highlighted the loose bolts. There was a slight defect on one of the prints but the other two in the trio were fine. I have also been having trouble adding supports and despite watching a couple of YouTube videos to make sure that what I'm attempting to do should result in additional supports, I still can't do it. Thanks for the tip about using save project, rather than a plain save. I'll try to remember that. For reasons unknown to me, I have just managed to save a couple of files with .cpddpl extensions. I haven't tried printing one of those yet. I was only trying to open the .cbt to see if I could see anything obviously adrift that might have caused the print failures that I was having. The settings I have used have, to the best of my knowledge remained unchanged since one of the first files I printed several days ago and I have subsequently (almost) successfully printed the most recent file again with the same settings. That said, the file currently printing does seem to be, with one possible exception out of four, printing just the supports and not the bodies again.