flubrush

Has anyone ever located an engineering drawing of the Class 303? I've been on the hunt for one, on and off, since the 1960s and all I could dig up was the diagrams with some dimensions. I did contact the company who produced the 4mm scale kit and they said that they had measured up from an actual unit to generate their own drawings. Jim.

They were three car sets from new and mostly ran in the 3 + 3 configuration as a six car set. They were in their own shade of blue based on Caledonian blue and had wrap round windscreens. Jim.

I've had similar problems with missing pixels on the LCD which gives vertical channels up the side of prints. It might be difficult to check if there are missing pixels, and specks of dirt or left over set resin on your FEP could cause the same problem. You could try moving the part in the slicer to a different position on the build plate to see if the problem goes away - or moves elsewhere. Jim.

I now use syringes to apply MEK/Butanone when building track with plastic chairs. I find that I can apply the correct amount quite easily and there are very few fumes compared to using a brush. You can also pick up and put down the syringe quite easily with one hand - no "brush in bottle" action required with the possibility of spilling the bottle. The syringes and blunt needles can be got from Ebay - maybe get an assortment of needle sizes to let you decide on what size is best for you. Jim.

When Draftsight announced their move to subscription, I dug around and found NanoCAD which is also a clone of AutoCAD LT. The free version download is at the bottom of this web page https://nanocad.com/products/ Their other paid-for products are also shown on that page. I've been using the free version for the past year and it's quite close to ACAD LT and Draftsight with a few slight variations. Jim.

S scale is half of Gauge 1. In fact in the UK, S scale was originally known as H1 (Half One) with a scale of 5mm:ft. The name was changed to S a few years after WW2 to come in line with the US name for the scale and the 1:64 scale was adopted as the UK standard. Jim.

Wayne, What's your method of construction - styrene sheet, 3D printing, ?? Jim.

Colin Seymour also has moulds for the whitemetal castings which go with the etches - well he did about ten years ago. I remember that (the late) Robin Fielding got sample runs from the moulds about ten years ago but he never went ahead with getting more runs done. I think we still have all the samples from these test runs - very nice castings. But I wish anyone luck in chasing this up. It would have been nice if the Society had been able to acquire the photo tools and the moulds when Alan sold the business but that didn't happen and I don't know if it could ever have happened. Jim.

Richard Barton was trying to drum up interest in getting a further run of the Terrier etches but didn't get enough numbers to justify proceeding. I wonder if Richard's interest might have flushed out any shelf queens. I've certainly got the masters for the castings in the Parts archive. Another source of kits would be the Alan Gibson ones, now long out of production. But I think I remember Stephen Rabone getting hold of all the etches left when Alan retired. He might know if anything survives although you would have to change interest to the LMS since I think Alan only did LMS locos in S scale. Getting kits re-scaled from other scales rarely works in S due to the minimum numbers required. I remember once enquiring about getting an etch re-scaled of a 4mm scale Caledonian tank loco and the minimum quantity quoted to me was 25, which was more than twice the number of prototypes. :-) I could have taken two, maybe three at a pinch, but I doubt if the other 22 would have been taken up by the remaining membership. You might want to DIY. :-) Have a read at Michael Woods' recent articles in the Gazette to see how he did it. [Later] Just remembered that there might still be some of the Hunslett kits remaining on the shelf at Judith Edge - not Southern, but Industrial. These kits are good since they come with all the fittings - you only need to put a chassis and wheels underneath them. Jim.

You might be thinking of photogrammetry where several pictures of a subject are used by software to generate a 3D file https://all3dp.com/1/best-photogrammetry-software/ ...or you go for 3D scanning software to run in your tablet https://www.3dnatives.com/en/top-10-low-cost-3d-scanners280320174/ Jim.

I hesitate to point out that a lot of wagons had nuts on the outside, so cutting small squares from 30thou by 10thou Microstrip could be used instead. And if you really want to go to town, you could drill 10thou (0.25mm) holes in the squares and insert short bits of 10thou rod to signify the bolt ends. If you really want to be anal, some Scottish companies used hex nuts. :-) Jim.

Will. Scott has given chapter and verse on the RCH wagon brake gear. In fact, Dave Provan's first etch was too tight and he re-drew it for the present version. It was designed around the Gibson WW1 wheel but some people have reported very tight clearances like you have, and the answer is to relieve the faces of the shoes with an oval needle file to get adequate clearance. I'm looking at maybe getting another brake gear etch designed along the lines of Dave's, but being a bit more universal to fit more wheelbases, and maybe have 3D printed resin brake shoes to avoid the possibility of shorts. Jim.

Will, In fact if your were turning up 5" gauge axles you would probably turn them between centres. :-) It's a more accurate way of getting concentric axles than using other methods. The critical point with small lathes is what diameter you can swing over the bed and that usually dictates what models you can attempt - like the diameter of a locomotive driving wheel, or the rear wheel of a traction engine. It might be worth getting a copy of a book like "The Amateur's Lathe" by L.H. Sparey. This is reckoned to be one of the best entry books for small lathes. I've done a quick Google and there seem to be plenty at pretty good prices. Here's a listing from Abebooks :- https://www.abebooks.co.uk/servlet/SearchResults?isbn=0852422881&cm_sp=mbc-_-ISBN-_-all The book has been on the go since 1948 and my copy is the fifth edition of 1972. I note that some of the editions in the web page have much late3r dates and I would advise you to go for as modern an edition as you can get since that will probably reflect the far East machines like the Seig lathes. In 1972 they were unknown and Myford was the "king of the walk". :-) Jim.

Will, Butanone from C&L is the recommended solvent for our chairs. I should have put a note with your order. For a few yards of track the bottle from C&L is probably the best economic bet. If you want to build a lot of track then a 500ml or 1 litre bottle of MEK from Ebay would be much better from cost per mL. I've also started using a hypodermic syringe to apply the solvent which I find much better than using a brush. Ebay (again) usually has a fair number of adverts for syringes - I find the 10mL size the handiest with a medium to fine needle. The MEK/Butanone doesn't seem to affect the parts of the syringe. The Seig SC2/3 should be fine for a lot of model work. Its spec is close to the Myford ML7 which was (still is?) the model engineer's standard lathe. Your only question might be how much distance you require between centres. 300mm on the SC2 looks a lot until you consider that the measurement is between plain centres in the spindle and the tailstock with the tailstock at its farthest distance from the headstock. Once you mount a three jaw chuck on the spindle and put a Jacobs chuck with a drill on the tailstock, your 300mm is probably down to around 150mm or maybe less. My ML10 has about 330mm between centres and I can't remember that proving a problem in the last forty-odd years. :-) Jim.

John, Those bead lathes that Simon has pointed to are quite interesting - almost a commercial Fonly lathe. :-) You might find that putting a plate on there bed and using tools like the ones described in the Fonly lathe pages could give you quite a good setup for machining loco fittings. Jim.

John, I've been going through this thread again and saw your commenst about lathes being a bit expensive. You might want to look at the Fonly lathe described on the 2mm Society web site - cheap as chips and fine for doing locomotive fittings and such like. http://www.2mm.org.uk/articles/fonly/fonlypt1.htm that's the opening page and there are links on the page to the full articles. Jim.

I had similar problems to you with my CNC mill when I started to cut brass. I had started cutting styrene and there were no great problems, but carbide cutters were going ping with monotonous regularity when I started on metal.. I dug around the net for speed and feed calculators but still got problems when following the settings they gave. Until I started questioning the speed of my spindle. I got myself a cheap electronic tacho and found that my spindle was running at half the speed indicated. I was able to adjust the speed upwards and matters started to improve greatly and the life of my cutters improved no end. But my settings are a lot less than yours since I use a 0.1mm depth of cut for my 0.5mm, 1mm and 2mm carbide slotting cutters. They run at 6000 rpm and the feed is 25mm/min for the 0.5mm, 50mm/min for the 1mm, and 230mm/min for the 2mm. These cutters should be running at speeds into five figures of RPM according to the manufacturers specs but if you lower feeds and depth of cut you can start to get reasonable performance with a slower running spindle. Try and nail down your spindle speed if you can. If it is running at around 1000rpm then you might have problems getting the smallest cutters to work. Jim.

A 0.2mm cutter radius is hardly noticeable and inner corners look, to all intents and purposes, square. I've use cutters between 0.5mm and 0.2mm radius in my CNC machine to "square" corners on profiles cut by larger diameter cutters and they look fine. My Emblaser 1 has a laser beam diameter of just under 0.2mm and cut a lot of window frames in fine card and they look square cornered. Jim.

John, Nowadays, another solution is to use a 3D printer to do the boiler fittings and you can either use the 3D prints on the model, or use it as a master for lost wax casting. I know that a 3D printer can be as expensive as a small lathe so maybe not for you to do it yourself. But find somebody who can do a print for you. In the SSMRS, that could be me. :-) I've already done prints of a Y7 chimney for some members and Caledonian chimneys and domes for myself. So if you can find a good drawing of what you ewant I can print it in S scale. 3D printing can be a godsend for S scale since modellers building locomotives usually only want one or two of any particular fitting, which can mean a lot of expense if you want one or two made or cast. Jim.

I've been printing directly on the build plate for my S scale wagon wheel centres. It works very well and the only consideration is that the burn on layers cause a slightly larger diameter due to light bleed and I've offset that by putting small rebates round the edges next to the baseplate. This is one of my tests of a three hole disc wheel. I also tried reducing the number of burn-on layers to reduce the increasing diameter problem and found that I could go down to two burn-on layers instead of the six recommended for the resin I'm using - Phrozen ABS-like Grey. I can get about thirty wheels on the plate. Technically I could get more but the wheels are so close together that excess resin stays between them and all the wheels come off in one sheet. :-) Jim.

I have found that the biggest factor in getting good prints is support placement. I use Chitubox and use its automatic function and adjust its output by adding or removing supports to avoid problems. I find that trying to imagine what happens when the partial print might act when being unstuck from the building plate helps. Jim.

Have you got any drawings of suitable buffer stocks and axleboxes? I might be able to print some up.

Scott, These bodies are looking good. Maybe an article in the Gazette is called for to show people that scratchbuilding wagons is probably as easy as building a kit. :-) Jim.

Mike, I suspect that it is similar to the Anycubic product. It's the resin I got along with the printer and I've been using it quite successfuly ever since. I only moved to the Rock Black because it is advertised as being stronger and it is black. :-) But both grey and black seem quite strong and withstand force fitting of the axle in the solid spoke and the disc wheels with only the tyre being supported. Pressing into the split spoke showed a bit of deflection and had to be taken gently. I'm looking at thickening the split spokes from 0.03mm to 0.035 or 0.04mm to provide a bit more strength. I also put chamfers and rebates on the rear edges of the wheel where it meets the plate to reduce the thickening of the resin with the first few extended duration layers. I also tried reducing the number of these layers from the recommended six and everything is still sticking on well at two layers. I chickened out going to one or none since I don't like cleaning out the resin tank. :-) The next experiment is to apply matt black paint since the "black" resin is quite translucent. An aerosol of Halford's "Go-fast" matt black has been laid on. :-) Jim.

I've also been printing small parts to mass produce wagon wheels. I use a Shuffle which is very similar to the Photon. This is an early stage using Phrozen Grey ABS resin. The tyres are turned steel. I'm making the centres an easy fit in the tyres and retaining them using cyanoacrylate glue. I've designed the spoke centre with raised lands to give registration which also allows clearance for the adhesive. A selection of wheels assembled using the Phrozen Grey, and the Phrozen Rock Black resin. ...and the latest test with split spoke centres using the black resin. I am also printing the the centres directly on the plate. ...and I have reduced the start layers to two instead of six and they are still staying firmly in place. The Stanley blade is my removal tool of choice. :-) The remarkable factor is the accuracy of the prints. I had expected to have to print the centres with no axle hole and to have to produce this in a lathe setup. But I tried printing the axle hole and reaming this out to be a push fit on the 2mm axles. I use a 2mm hand reamer and restrict its depth of cut to leave a small taper to give a press fit. This reaming can be done in a drill press. All construction can be done in a drill press so that everything is assembled square. I've checked the runout on the samples I have done so far and they average 0.002" - 0.003" TIR which is comparable to similar products from good suppliers. I can pack 32 prints on a plate and the prints take about twenty minutes (58 x 50micron layers) so pretty close to mass production for resin printing. :-) S scale. :-) Jim.