flubrush

I've been pushing on with the 16T mineral but still running into some problems. I placed beams across the bottom of the sides to stop the sides warping while printing and curing. At first I only did the cross-wise beams then found that the ends were bellying outwards, so a longitudinal beam was added to control the ends. The door end has turned out well apart from the top girder which has got a rippled edge to it. It is 0.2mm thick and increasing its thickness to 0.25mm will probably cure that. The sides have stayed reasonably straight with a slight bow inwards. I'm looking at putting a plug in the sides to old them straight while curing to see if that can be avoided. The main problem is the diagonal ridges seen here on the sides, the worst ones being the one on the left over my thumb and the one on the right at the other end of the side. They seem to be triggered by where the horizontal beams or the door bottom start. I'm not sure if this could be down to the supports being too flexible, or it might be down to the Z column in the Phrozen printer being too flexible. This has been a complaint since the Sonic Mini 4K appeared on the scene and Phrozen have brought out an upgrade to correct the problem. I've ordered one of the upgrades and I'll wait until I've installed it before trying more prints. Jim.

I remember being part of a film crew in Glasgow shooting a scene for a drama series in the 1970s - "A View From Daniel Pike". The location was on the Clyde shore under the Finnieston crane - that's the big hammerhead crane that you see on publicity views of Glasgow these days, built to load locos from North British loco works on to ships. The scenes were being shot at night so required a lot of lighting. When the lights were being set up in the darkness, one of the lights happened to be shone up onto the crane and that started off Lord knows how many thousand of Glasgow's starlings - the crane being their night time roosting place. The first result of this was that starlings do what starlings do when wakened up rudely from their sleep and the whole film crew had to exit the location at full speed to avoid the downpour of bird lime. :-) When the lime storm had stopped, the next problem was that the starlings weren't going to keep quiet about it. I was the sound recordist and I couldn't record good sound for the scenes for over an hour after the whole thing kicked off. :-) It was a lesson learned the hard way for the film crew. :-) Starlings were very much the bird of my childhood. We moved to a new housing scheme on Clydeside just after the war and the starlings moved as well - finding excellent nesting places in the roofs of the houses. The housing scheme had thousands of starlings roosting in every roof and walking round your house threatened being hit by bird lime. :-) I now live close to Bristol and seeing a starling is a rarity. Jim.

Rob, I'll try something like that to see if that solves the problem. I've been thinking about something like that since I remember a thread on RMWEB some time ago when people were mounting rolling stock bodies with no floors on disposable sub-frames to avoid the sides distorting, but I haven't found it yet. I haven't tried any more printing so far since I've been getting more involved in the finer points of working with Solid Edge. :-) Jim.

Rob, There is a small flange there at the moment which goes to represent the fillet created at the bottom of the sides and fixed end as shown in the Charles Roberts drawings I'm working from :- ...which probably doesn't add too much strength - its cross section is an isosceles triangle with 0.6mm equal sides. But it will supply a stop against which the metal floor will fit. I've just ordered up some 1.2mm and 1.6mm nickel silver sheet which I should get next week to use for the floors. 1.2mm is my preferred thickness but I'm getting the 1.6mm option in case the increase in weight is not enough with the 1.2mm floor. I'll cut the floor on the CNC mill to get it accurate without much sweat :-) . and I will try cutting the floor joint lines with an etching cutter. I've re-drawn the sides with an 0.8mm to 0.6mm inside taper on the sides to try that thickening of the sides and I've also got the option to go further, maybe up to a 1mm to 0.6mm taper. I'm also learning a lot more about Solid Edge in the process. It provides two methods of working - "Ordered", which looks as though it is equivalent to the way Fusion 360 works and allows you to adjust models by altering the original sketches and "Synchronous" which provides editing on the finished 3D models. The more modern "Synchronous" method is the preferred method in all the tutorials and finding out about all the "Ordered" methods is a bit difficult to extract from all the tutorial material available - but I'm getting there. :-) Jim.

Rob, One thing I have noted when printing the sides and ends of my 16T mineral wagon is that the bottom of the sides tends to warp in places even when leaving everything on the supports when hardening. I'm trying some thickening of the sides - from 0.6mm to a tapered 0.8mm to 0.6mm from bottom to top to see if the increased thickness at the bottom might might improve matters. I'm also looking at inserting a nickel silver floor in place before curing to see if that improves matters. The tops of the sides seem to be OK so the top angle seems to be doing the job it was doing on the prototype. :-) Jim.

I might add my experience of a year or two ago when I was ballasting my American switching layout. I normally use the method of damping the ballast and dropping on diluted PVA or latex glue with drops of washing up liquid added. The ballast I had was some I had acquired way back in the eighties - one of the Woodlands products I think it was. All seemed to go well with the ballasting until a day or two later when I found that the ballast had swelled to a height sufficient to foul the wheel flanges. I suspect that the ballast had been made from some material like ground bark which could absorb water. Next time I'll make sure it's made from stone. :-) Jim.

Just to keep up with all the others, here's my mineral wagon in Solid Edge :- This is in the Assemble function in Solid Edge, where you start with a base part and add all the other parts to it. The base part is the "bodysides-01.par" at the top of the list on the left and the other parts are added to it. I'm still experimenting with how best to print this. The sides are 0.6mm thick so they are quite flexible when printing. I had one pretty successful print in 2019 - at 45 degrees orientation - but it had a floor. The body was very light so I am now trying to print with no floor, the intention being to add a floor of 48 thou or 64 thou brass or nickel silver to add weight to the wagon. The intended underframe is the Rumney Models underframe. I'm just about to try some more experiments at different orientations to see if I get success. The main problem is that in a lot of the orientations, the fine angle work and door strips have to be supported and that gives a knock-on of cleaning off support marks which is not too easy on fine 0.2mm angle edges. I've heard it said that the key to success in 3D printing is getting to know a 3D CAD package. I would suggest that it is more like learning how to orientate and support in the slicer. ;-) Jim.

Dave also had all the discussions with Parkside Dundas who produced the plastic body. Jim.

Just to clarify, Dave designed the underframe. I was the Parts Officer at the time. :-) Jim.

I got the tip to use carbide cutters on styrene from a G1 modeller some years ago. I think the theory is that the cutters are sharper than HSS and don't generate heat when cutting. Typical settings for me with styrene are - 5mm cutter : 500mm/min:0.2mmDOC:3000rpm; 2mm cutter : 350mm/min;0.2mmDOC;3500rpm; 1mm cutter : 240mm/min; 0.2mmDOC; 4000rpm. I could push things harder but I find that the styrene starts flexing in front of the cutter and I don't get the finish I require. I mostly cut styrene to make panelled coach and freight stock sides so I'm looking for a very smooth finish on the panels, which I get at the speeds and feeds given. I've occasionally had a look at the Stepcraft style of mill mainly to investigate larger table movements. The KX1 is practically about 250mm x 100mm which can get a bit restricting with some models. I cut the frames for a 1:32 scale tank loco and there's a join hidden behind the rear driver. :-) Jim.

I'll just chuck in my experience when working with small cutters, established after a very expensive start with a large pile of broken cutters. I use carbide two flute slotting cutters for everything. I cut a fair bit of styrene and I find that the carbide cutters are the only type that will deal with styrene and leave a good finish. When cutting brass, aluminium alloy or steel, with a 1mm diameter cutter, I use a feed rate of 50mm/min with a depth of cut of 0.1mm. With a 0.5mm cutter I use a feed rate of 25mm/min, again with a DOC of 0.1mm. Both cutters are run at 6000rpm. I know these figures are on the conservative side but I get a good long life out of the cutters and I now retire cutters when they are getting blunt rather than hear them go ping. :-) The machine is a Seig KX1 and its top spindle speed is 7000rpm which is a bit of a limitation with small cutters when I should be looking at spindle speeds well into five figures. Jim.

In the 1970s, such a programme would probably be made on film so there could be a chance of its survival since modern film has excellent storage properties. Jim.

I got a Seig KX1 CNC machine about eleven years ago and that has made up for my increasing lack of hand and eye co-ordination. :-) Jim.

Emailed support last night and got a response from Liam this morning. He pointed out a possible cause and he was right. :-) I haven't been using the Emblaser for almost two years for a lot of reasons and I had forgotten a few things to check out. In this case it was the laser cover which had been displaced slightly to open the safety micro switch. Re-seating the cover has got everything back working. I suspect that the cover had caught on one of the cutout sections on the last job and got displaced slightly. I was cutting 0.8mm ply which does warp and I suspect that one of the cutout parts had popped up enough to hit the guard. Just to put a bit of content in the thread, The work I was doing was some test cuts to prove the construction of a large warehouse for an N scale layout. The prototype is the B&O warehouse at Camden yards in Baltimore. The prototype :- ...and a closer look at the detail :- Here are the first test cuts to prove that I could make the building from sections between window centre lines :- ...and the lot stuck together :- The bricks are a bit overscale for N. With my laser kerf being a natz under 0.2mm it made the mortar lines look oversize with a scale sized brick. So I upped the brick to an approximate scale 12" x 5" x 4" and it looks not too bad on a large building and the 5" depth is a fair match for the 0.8mm ply for doing interlocked corners. The bricks are etched at one pass at 10mm/sec at 10% power. However I draw my bricks as rectangles and etch round each rectangle so each mortar line finishes up getting two passes and these settings give a fair relief depth. I've yet to experiment with how I'm going to paint the thing, so I might vary the etch depth. Cutting out is done with eight passes at 95% power at 15mm/sec. and that cuts through cleanly. Seven passes is not quite enough. I have to confess I didn't clean the lens after the machine was lying dormant for almost two years, so pass counts and speeds might vary when I actually get round to a bit of cleaning. :-) Jim.

My Emblaser 1 has stopped working. Well the mechanics are fine and the laser diode is working but I have lost program control of the laser. If I press the laser button to set the laser on for cutting, the laser diode comes on at what looks like full power but the light by the button doesn't blink after a second and doesn't stay on when the button is released. I've tried a message to the Darkly Labs forum but I'm not holding out much hope since there hasn't been any traffic on the E1 forum for a year or so. I've looked at their spares but there is nothing for the PCB where I suspect that the problem is. Anyone heard of anyone else with a similar problem? I've started having a look round the web to see if there are any GRBL/Arduino bits which might be a substitute - maybe. :-) I don't really want to wtite of a piece of gear that's just over four years old. Jim.

In a way similar to Bill Blackburn's method, but possibly a bit safer, :-) I have used my RSU at full whack to do the heating. I had the Code 40 wire rail and I chopped it into roughly 18" lengths. One end of the rail length was clamped in my bench vice and one lead of the RSU was attached to the vice. The free end of the length of rail was held in a pair of pliers and the croc clip of the other RSU lead was clipped to the rail next to the plier jaws. Hit the foot switch of the RSU and when the rail starts to glow red hot, then give it a sharp pull tight - similar to what you would do with unheated copper wire to straighten it. It worked and the rail was pretty well straight. Jim.

Have you checked the slicer files for the ones printed on the plate to see if there is a "hole" in the files near the top. You can single step through the files on the Chitubox slicer to check things out. I've had the occasional "funny" on Chitubox when a slice doesn't represent what it should which I have got rid of by doing something like rotating the part a degree or two. In your case, raising the part on supports might be changing things to get rid of the blemish. Jim.

In Glasgow, more likely to be a sandstone wall rather than brick. Jim.

I think I'll stick with the Mini 4K - for a start I've run out of room for any more equipment and my old Shuffle is on the floor at the moment. :-) I have tended to print small objects like wagon springs and axleboxes so the smaller plate size is no problem and my cleaning and curing process is geared up to small items. If I got a printer with a larger plate I would have to get a larger ultrasonic bath to match the plate size. And the pixel size of the larger plate machines is not as small as the Mini 4K and I like the improved resolution on the smaller parts. Jim.

Ian, In a lot of cases when modelling pre-Grouping railways, the smaller 4mm scale rail and chairs are closer to scale than our S scale rail and chairs. Our components are based on British standards from Grouping onwards where the rail and chairs were substantial enough to carry the increased weight of locomotives and rolling stock from the start of the 20th century. In Victorian times, the rail and chairs were of lighter weight and smaller dimensions. I think I remember Geoff Stenner telling me that track on his Victorian era layout had been laid using 4mm components. Jim.

Just as a follow up, here's the Vectric web site on the laser add-on https://www.vectric.com/products/laser-module I think I remember it costing about £50 but you also need the latest V10.5 of Cut2D desktop to run it. Jim. [Later] The cost is £39 - just found it digging around on the Vectric website.

I'm just about to start using mine after a lay-off most modelling for a year - its the original Emblaser 1 using Cut2D Laser in its last upgrade form. I reckon there are bugs in this update and I'm looking at using a recent laser add-on to Cut2D Desktop which I use for CNC milling. I tried to have some discussion about the bugs in Cut2D Laser with Vectric a year or so ago but they weren't very interested and I suspect they had already decided to do an add-on to the Desktop version rather than continue with the original Laser version.

Have you adjusted the end sizes of your supports? I remember once adjusting the ends of supports in Chitubox for work on my Shuffle and I had reduced the diameter at the conical end of the supports to 0.15mm when the Shuffle and Phrozen ABS Grey resin had a minimum size of barely 0.2mm. I turned out a few prints like yours until it dawned on me what was going on. Jim.

I go a Phrozen Sonic Mini 4X a few weeks ago and it has worked well from day one. I've run a few tests - like the rook and the Amerilabs test - and have done about ten runs of a NER hopper body which I'm developing at the moment with no problems. I had one failed print but I put that down to a dodgy file for the printer since I've picked up faults in subsequent slicer outputs which I've corrected before printing. I'm using the Phrozen Grey 4X resin and I run the printer in an ambient temperature of 26C - 27C, having built a cabinet to house the printer with a 100 watt temperature controlled fan heater based on examples shown on YouTube. My previous experience was with a Phrozen Shuffle 2018 which was also pretty reliable with few failures. Jim.

Paul, How many dozen do you need? :-) :-) :-) Jim.