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Railway Double Track Tunnel Internal Arches Add On ","price":3.85,"description":"This is an add-on component for my double track tunnel portal. \n\nThe portal section can be found here https://www.cgtrader.com/3d-print-models/games-toys/other/model-railway-tunnel-portal-double-track-modular-design\nThis is the internal arch for a tunnel. \n\nOn many model railways people have tunnel and when a train goes through it ends up in a cavernous hole rather than something looking like a tunnel. So I have developed this add-on component for my double track portal. These come on various lengths and can be put together to create the required length. This item comes in the following lengths 12mm, 24mm, 42mm, 84mm, 168mm and 252mm\n\nI will also be adding versions for 2nd , 3rd and 4th radius track in due course (2nd Radius 438mm, 3rd Radius 505mm and 4th Radius 572mm), for other radiuses you can use straights with curved sections together.\nThese can also be used with tunnel portal to create bridges if required.\n\ndesigned at OO gauge, 1/76.2 scale but can easily be scaled for other gauges.\nfor HO gauge print at 87%, 1/87 Scale,\nfor TT print at 63.5% 1/120 Scale,\nfor O gauge UK at 175%, 1/43.5 Scale,\nfor O gauge International print at 158%, 1/48 Scale,\nfor N gauge print at 51.49%, 1/148 Scale\n\nThe examples in the pictures were printed on a Bambu Labs A1 FDM Printer.\nAs normal with my designs, there is a balance between accuracy and printability, hopefully not affecting the look of the model too much. \n\nFor FDM printing, I used a 0.4mm nozzle and a layer height of 0.12mm using PLA or PLA+ filament. PETG is also a very good choice. Designed to be printed inverted with no supports.\nI used the following Filament: ELEGOO PLA+ Filament 1.75mm Grey 1KG  - https://amzn.to/4r1qQIM (Affiliate Link)\n\nuse this link to join CGTrader and download my designs.\n\nhttps://www.cgtrader.com/designers/PJD1974?referral_id=3218445","imageAlt":"Model Railway Double Track Tunnel Internal Arches Add On","url":"https://www.cgtrader.com/3d-print-models/games-toys/other/model-railway-double-track-tunnel-internal-arches-add-on","isCLDApplicable":false,"isSaleOffApplicable":true,"gaAttributes":{},"primaryImage":{"gridFallbackUrl":"https://media.cgtrader.com/variants/x7b9pxzu9uck1zcuhwl8s2748uqa/a26e47dab5f2d22c43d6c5ce4b4b46ecc30c70918878397cba1a10c1e35d7bfc/Screenshot%202025-05-02%20133135.jpg","gridUrl":"https://media.cgtrader.com/variants/x7b9pxzu9uck1zcuhwl8s2748uqa/78add9c2f02fbd73a43ffb3970be38683c5f15eff6ca849dc78c644f4ff9ce1b/Screenshot%202025-05-02%20133135.webp","isAdultContent":false},"modelInfo":{"modelUrl":"https://www.cgtrader.com/3d-print-models/games-toys/other/model-railway-double-track-tunnel-internal-arches-add-on","isCgtVerified":false,"types":{"printReady":true,"animated":false,"pbr":false,"rigged":false,"lowPoly":false}},"metaverseFormatsList":[{"id":51,"name":".stl","is_native":false},{"id":5,"name":".fbx","is_native":false},{"id":12,"name":".obj","is_native":false},{"id":null,"name":null,"is_native":false}],"categorySlug":"games-toys","subcategorySlug":"other","categoryTitle":"Games \u0026 Toys","subcategoryTitle":"Other","schemaImageUrl":"https://img-new.cgtrader.com/items/6092943/51810dbf00/model-railway-double-track-tunnel-internal-arches-add-on-3d-model-51810dbf00.webp","saleOffDiscount":30,"eligibleForSubscription":true,"subscriptionSubscribed":false,"subscriptionPotential":true}},{"id":"6073844","type":"listingItem","attributes":{"id":6073844,"title":"Model Railway Tunnel Portal Double Track Modular Design","price":4.4,"description":"Recently, I have been working on a tunnel for my model railway club, and as I was working on it, I decided to do a very similar design to share and could easily be used for a railway bridge.\n\nThis design has been designed to be printed inverted and, therefore, will not need any supports. I have printed several of these now without supports, and they have come out well. The tunnel is a stone brick design and has several parts that are enhanced to improve the look.\n\nWhilst researching this design I found  that tunnels come in so many different forms, and the surrounding support walls also come in lots of different arrangements. Therefore, as I develop this design, I will be adding several add-on components to help with building tunnels and bridges. (I am starting this project in April 2025 and will add components going into the summer of 2025.) I am also adding a single-track portal and add-ons.\n\nThe add-on components I’m looking at adding are:\t\n\n\tTunnel Side Extension Support Walls (also the ability to have two tunnels next to each other) https://www.cgtrader.com/3d-print-models/games-toys/other/model-railway-tunnel-portal-extension-buttress-joiner-add-on\n\tTapered Support Walls\n\tStraight Internal Arch - https://www.cgtrader.com/3d-print-models/games-toys/other/model-railway-double-track-tunnel-internal-arches-add-on\n\t2nd Radius Curved Internal Arch\n\t3rd Radius Curved Internal Arch\n\t4th Radius Curved Internal Arch\n\nCurved internal Arches will be made up of 2 degree and 6 degree segments, can also be formed with other arch sections to form exactly what you need that is not 2nd, 3rd or 4th radius. \n\ndesigned at OO gauge, 1/76.2 scale but can easily be scaled for other gauges.\nfor HO gauge print at 87%, 1/87 Scale,\nfor TT print at 63.5% 1/120 Scale,\nfor O gauge UK at 175%, 1/43.5 Scale,\nfor O gauge International print at 158%, 1/48 Scale,\nfor N gauge print at 51.49%, 1/148 Scale\n\nThe examples in the pictures were printed on a Bambu Labs A1 FDM Printer.\nAs normal with my designs, there is a balance between accuracy and printability, hopefully not affecting the look of the model too much. \n\nFor FDM printing, I used a 0.4mm nozzle and a layer height of 0.12mm using PLA or PLA+ filament.\nI used the following Filament: ELEGOO PLA+ Filament 1.75mm Grey 1KG  - https://amzn.to/4r1qQIM (Affiliate Link)\n\nuse this link to join CGTrader and download my designs.\n\nhttps://www.cgtrader.com/designers/PJD1974?referral_id=3218445","imageAlt":"Model Railway Tunnel Portal Double Track Modular Design","url":"https://www.cgtrader.com/3d-print-models/games-toys/other/model-railway-tunnel-portal-double-track-modular-design","isCLDApplicable":false,"isSaleOffApplicable":true,"gaAttributes":{},"primaryImage":{"gridFallbackUrl":"https://media.cgtrader.com/variants/42gm9mmynoep45gemt0c8agb8i4v/a26e47dab5f2d22c43d6c5ce4b4b46ecc30c70918878397cba1a10c1e35d7bfc/Screenshot%202025-04-21%20182717.jpg","gridUrl":"https://media.cgtrader.com/variants/42gm9mmynoep45gemt0c8agb8i4v/78add9c2f02fbd73a43ffb3970be38683c5f15eff6ca849dc78c644f4ff9ce1b/Screenshot%202025-04-21%20182717.webp","isAdultContent":false},"modelInfo":{"modelUrl":"https://www.cgtrader.com/3d-print-models/games-toys/other/model-railway-tunnel-portal-double-track-modular-design","isCgtVerified":false,"types":{"printReady":true,"animated":false,"pbr":false,"rigged":false,"lowPoly":false}},"metaverseFormatsList":[{"id":51,"name":".stl","is_native":false},{"id":12,"name":".obj","is_native":false},{"id":5,"name":".fbx","is_native":false},{"id":null,"name":null,"is_native":false}],"categorySlug":"games-toys","subcategorySlug":"other","categoryTitle":"Games \u0026 Toys","subcategoryTitle":"Other","schemaImageUrl":"https://img-new.cgtrader.com/items/6073844/fcb112b36c/model-railway-tunnel-portal-double-track-modular-design-3d-model-fcb112b36c.webp","saleOffDiscount":30,"eligibleForSubscription":true,"subscriptionSubscribed":false,"subscriptionPotential":true}},{"id":"6110778","type":"listingItem","attributes":{"id":6110778,"title":"Model Railway Tunnel Portal Extension Buttress Joiner Add-on","price":3.85,"description":"When I was designing this set of designs I was doing it for my Model Railway Club and there was a clear need for the ability to have two tunnels next to each other in some circumstances. As these tunnels could be various distances apart then I also needed various sizes between buttresses. On railways with embankments there is often supporting walls either side of the tunnel portal and this can be achieved with this add-on.\n\nWithin this add-on there is a joining buttress with groves on both sides to slot portals and extension walls in. The extension adds approximately 6mm of width to the wall face. The extension walls come in four sizes of 30mm, 60mm, 90mm and 120mm with 6mm at each end that slots into the buttresses. These walls are the same height as the portals at 116mm tall and the extension buttress is approximately 125mm tall. \n\nWhilst researching this design I found that tunnels come in so many different forms, and the surrounding support walls also come in lots of different arrangements. Therefore, as I develop this design, I will be adding several add-on components to help with building tunnels and bridges. (I am starting this project in April 2025 and will add components going into the summer of 2025.) I am also adding a single-track portal and add-ons.\n\nThe add-on components I’m looking at adding are:\t\n\nTunnel Portal Fronts (Single and Double)\n    https://www.cgtrader.com/3d-print-models/games-toys/other/model-railway-tunnel-portal-double-track-modular-design\n    https://www.cgtrader.com/3d-print-models/games-toys/other/model-railway-tunnel-portal-single-track-modular-design\n\nCurved internal Arches will be made up of 2 degree and 6 degree segments, can also be formed with other arch sections to form exactly what you need that is not 2nd, 3rd or 4th radius. \n\ndesigned at OO gauge, 1/76.2 scale but can easily be scaled for other gauges.\nfor HO gauge print at 87%, 1/87 Scale,\nfor TT print at 63.5% 1/120 Scale,\nfor O gauge UK at 175%, 1/43.5 Scale,\nfor O gauge International print at 158%, 1/48 Scale,\nfor N gauge print at 51.49%, 1/148 Scale\n\nThe examples in the pictures were printed on a Bambu Labs A1 FDM Printer.\nAs normal with my designs, there is a balance between accuracy and printability, hopefully not affecting the look of the model too much. \n\nFor FDM printing, I used a 0.4mm nozzle and a layer height of 0.12mm using PLA or PLA+ filament.\nI used the following Filament: ELEGOO PLA+ Filament 1.75mm Grey 1KG  - https://amzn.to/4r1qQIM (Affiliate Link)\n\nuse this link to join CGTrader and download my designs.\n\nhttps://www.cgtrader.com/designers/PJD1974?referral_id=3218445","imageAlt":"Model Railway Tunnel Portal Extension Buttress Joiner 1","url":"https://www.cgtrader.com/3d-print-models/games-toys/other/model-railway-tunnel-portal-extension-buttress-joiner-add-on","isCLDApplicable":false,"isSaleOffApplicable":true,"gaAttributes":{},"primaryImage":{"gridFallbackUrl":"https://media.cgtrader.com/variants/xfgzy1erwu9rvbgza99eh9140bob/a26e47dab5f2d22c43d6c5ce4b4b46ecc30c70918878397cba1a10c1e35d7bfc/Screenshot%202025-05-23%20132345.jpg","gridUrl":"https://media.cgtrader.com/variants/xfgzy1erwu9rvbgza99eh9140bob/78add9c2f02fbd73a43ffb3970be38683c5f15eff6ca849dc78c644f4ff9ce1b/Screenshot%202025-05-23%20132345.webp","isAdultContent":false},"modelInfo":{"modelUrl":"https://www.cgtrader.com/3d-print-models/games-toys/other/model-railway-tunnel-portal-extension-buttress-joiner-add-on","isCgtVerified":false,"types":{"printReady":true,"animated":false,"pbr":false,"rigged":false,"lowPoly":false}},"metaverseFormatsList":[{"id":51,"name":".stl","is_native":false},{"id":5,"name":".fbx","is_native":false},{"id":12,"name":".obj","is_native":false},{"id":null,"name":null,"is_native":false}],"categorySlug":"games-toys","subcategorySlug":"other","categoryTitle":"Games \u0026 Toys","subcategoryTitle":"Other","schemaImageUrl":"https://img-new.cgtrader.com/items/6110778/3b2833703b/model-railway-tunnel-portal-extension-buttress-joiner-add-on-3d-model-3b2833703b.webp","saleOffDiscount":30,"eligibleForSubscription":true,"subscriptionSubscribed":false,"subscriptionPotential":true}},{"id":"6080061","type":"listingItem","attributes":{"id":6080061,"title":"Model Railway Tunnel Portal Single Track Modular Design","price":4.4,"description":"Recently, I have been working on a tunnel for my model railway club, and as I was working on it, I decided to do a very similar design to share and could easily be used for a railway bridge.\n\nThis design has been designed to be printed inverted and, therefore, will not need any supports. I have printed several of these now without supports, and they have come out well. The tunnel is a stone brick design and has several parts that are enhanced to improve the look.\n\nWhilst researching this design that tunnels come in so many different forms, and the surrounding support walls also come in lots of different arrangements. Therefore, as I develop this design, I will be adding several add-on components to help with building tunnels and bridges. (I am starting this project in April 2025 and will add components going into the summer of 2025.) I have also added a double-track portal and add-ons.\n\nThe add-on components I’m looking at adding are:\t\n\n\tTunnel Side Extension Support Walls (also the ability to have two tunnels next to each other) https://www.cgtrader.com/3d-print-models/games-toys/other/model-railway-tunnel-portal-extension-buttress-joiner-add-on\n\tTapered Support Walls\n\tStraight Internal Arch\n\t2nd Radius Curved Internal Arch\n\t3rd Radius Curved Internal Arch\n\t4th Radius Curved Internal Arch\n\nCurved internal Arches will be made up of 2 degree and 6 degree segments, can also be formed with other arch sections to form exactly what you need that is not 2nd, 3rd or 4th radius. \n\ndesigned at OO gauge, 1/76.2 scale but can easily be scaled for other gauges.\nfor HO gauge print at 87%, 1/87 Scale,\nfor TT print at 63.5% 1/120 Scale,\nfor O gauge UK at 175%, 1/43.5 Scale,\nfor O gauge International print at 158%, 1/48 Scale,\nfor N gauge print at 51.49%, 1/148 Scale\n\nThe examples in the pictures were printed on a Bambu Labs A1 FDM Printer.\nAs normal with my designs, there is a balance between accuracy and printability, hopefully not affecting the look of the model too much. \n\nFor FDM printing, I used a 0.4mm nozzle and a layer height of 0.12mm using PLA or PLA+ filament.\nI used the following Filament: ELEGOO PLA+ Filament 1.75mm Grey 1KG  - https://amzn.to/4r1qQIM (Affiliate Link)\n\nuse this link to join CGTrader and download my designs.\n\nhttps://www.cgtrader.com/designers/PJD1974?referral_id=3218445","imageAlt":"Model Railway Tunnel Portal Single Track Modular Design","url":"https://www.cgtrader.com/3d-print-models/games-toys/other/model-railway-tunnel-portal-single-track-modular-design","isCLDApplicable":false,"isSaleOffApplicable":true,"gaAttributes":{},"primaryImage":{"gridFallbackUrl":"https://media.cgtrader.com/variants/nfof6k2brh4ulscoj2q5lr77wgiz/a26e47dab5f2d22c43d6c5ce4b4b46ecc30c70918878397cba1a10c1e35d7bfc/thumbnail_IMG_5236.jpg","gridUrl":"https://media.cgtrader.com/variants/nfof6k2brh4ulscoj2q5lr77wgiz/78add9c2f02fbd73a43ffb3970be38683c5f15eff6ca849dc78c644f4ff9ce1b/thumbnail_IMG_5236.webp","isAdultContent":false},"modelInfo":{"modelUrl":"https://www.cgtrader.com/3d-print-models/games-toys/other/model-railway-tunnel-portal-single-track-modular-design","isCgtVerified":false,"types":{"printReady":true,"animated":false,"pbr":false,"rigged":false,"lowPoly":false}},"metaverseFormatsList":[{"id":51,"name":".stl","is_native":false},{"id":12,"name":".obj","is_native":false},{"id":5,"name":".fbx","is_native":false},{"id":null,"name":null,"is_native":false}],"categorySlug":"games-toys","subcategorySlug":"other","categoryTitle":"Games \u0026 Toys","subcategoryTitle":"Other","schemaImageUrl":"https://img-new.cgtrader.com/items/6080061/d306940f64/model-railway-tunnel-portal-single-track-modular-design-3d-model-d306940f64.webp","saleOffDiscount":30,"eligibleForSubscription":true,"subscriptionSubscribed":false,"subscriptionPotential":true}},{"id":"6104161","type":"listingItem","attributes":{"id":6104161,"title":"Model Railway Single Track Tunnel Internal Arches Add On ","price":3.85,"description":"This is an add-on component for my single track tunnel portal. \n\nThe portal section can be found here https://www.cgtrader.com/3d-print-models/games-toys/other/model-railway-tunnel-portal-single-track-modular-design\nThis is the internal arch for a tunnel. \n\nOn many model railways people have tunnel and when a train goes through it ends up in a cavernous hole rather than something looking like a tunnel. So I have developed this add-on component for my single track portal. These come on various lengths and can be put together to create the required length. This item comes in the following lengths 12mm, 24mm, 42mm, 84mm, 168mm and 252mm\n\nI will also be adding versions for 2nd , 3rd and 4th radius track in due course (2nd Radius 438mm, 3rd Radius 505mm and 4th Radius 572mm), for other radiuses you can use straights with curved sections together.\nThese can also be used with tunnel portal to create bridges if required.\n\ndesigned at OO gauge, 1/76.2 scale but can easily be scaled for other gauges.\nfor HO gauge print at 87%, 1/87 Scale,\nfor TT print at 63.5% 1/120 Scale,\nfor O gauge UK at 175%, 1/43.5 Scale,\nfor O gauge International print at 158%, 1/48 Scale,\nfor N gauge print at 51.49%, 1/148 Scale\n\nThe examples in the pictures were printed on a Bambu Labs A1 FDM Printer.\nAs normal with my designs, there is a balance between accuracy and printability, hopefully not affecting the look of the model too much. \n\nFor FDM printing, I used a 0.4mm nozzle and a layer height of 0.12mm using PLA or PLA+ filament. 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