PeterW

Night vision.... turns the darkest night into day, nowhere for the undead or other face hugging beasties to hide. One starparty there was a loud rustle and expletive mumble... a fellow observer had fallen off the path into a Bush! Peter

Screaming hedgehogs can be off putting, it’s amazing the noise they can make. I used to have a cat that liked to hide under bushes and then run and pounce on your legs in the dark and then scarper. If you are going to be out in their world they mig as well have some fun! PEter

Also looked like you needed to print with a greater number of walls/ceiling/floor, increases part strength a lot. I usually run with 4, but used 8 for a colleague recently who expected his part to get dinked in usage. I rarely go above 40% infill as the walls provide most of the strength and the part is nearly solid beyond about 60% infill. Also 0.2mm layers are good for most stuff (0.4mm nozzle), prints faster. Of course I am currently printing some lithopane a so down to 0.1mm or batter for the resolution. looks like you’re getting the hang of things! Peter

#late to the party I joined the green side a few years earlier. Good to see you’ve had success. PEter

Alan, James, I need to pay you guys a visit... the places I have found badgers locally seem to be missing them of late. peter

People are starting to make rocket nozzles with 3D printing. The latest machines make material with better properties than wrought, but there are still concerns about the cost effective validation of parts that are hindering uptake. Some lower temperature turbine blades and blade repairs are being undertaken already. All users need to assess the properties they need and the risk and implications of failure. Many people are happy with cast material which can have many more internal defects.... the technology continues to rapidly evolve, so what wasn’t possible a few years back is now easy to achieve.... interesting times. PEter

genuine Pruse stuff starts at around £300, that sounds like a cheap clone and not worth getting. Prusa is based off opensource, but they’ve improved it and they deliver very good results. The only hot bit on the printer is the nozzle and that can really only melt a tiny bit of material, so I’m not too concerned about long runs. I’ve had print stops where the head stays hot with filament in and cases where the head thermocouple fails and the heater runs off and “the magic smoke expires”. I’d make sure the printer is sat on a nicely non flammable surface and away from stuff that could be made to burn. Of course, everyone should make themselves happy with the choices they take, each printer will behave in its own random way (don’t you just love them!) A professional FDM user was bemoaning the lack of sensorS on even the Pro FDM machines, compared to over 100 sensors on the latest metal laser sintering machines. there is certainly still some improvements that could be made. Peter

If there are gaps in the lines of the first layer or the nozzle is so close you barely get any extrusion then you need to tilt the bed to get it nice and even across the bed. I apologise for emptying the Clas Ohlsen stock of purple glue! Sometimes I also get through quite a few razor blades to get the prints separated. I have run 72hr builds before, the only issues are “print gremlins” and particle emission (cool printing of PLA minimises these with respect to other materials). Peter

You need to relevel everytime you turn it on and check it every now and then, depending on how the first layer goes down. Always worth a relevel before any big jobs too. Peter

Bed adhesion.... black magic!! The slightly rough build sheets work quite well, some people like really clean glass, I use lots of purple glue, others hairspray. Getting the adhesion and nozzle height are key, the “default” temperatures should be less of an issue. At least you don’t need to wait long to see that something hasn’t stuck, so you can tweak things a little more. good luck. Peter

Some machines set the temperature on the machine, some in the slicer. You should be able to see and change the temperatures on the printer itself, so you’re sure what you’ve got. Also useful to sometimes over extrude a little if the prints turn up a bit weak. I tried improved high speed PLA recently and had nothing but problems, sure I could have made it work, but don’t have the time. Normal PLA is good for most things. PEter

@Gina has the point. You need the bed level so it’s the same height from the nozzle all the way across AND the printer needs to know where the bed is so it can print the right height. The optimum height is where a normal bit of paper just has friction between the bed and nozzle (making very sure that the nozzle does NOT have any bits of plastic protruding from it). Auto bed sensing systems can do this for you, IF they have been set up properly. If in doubt turn it off and back on and restart the calibration from scratch. I’ve seen what you’ve described when I’ve changed something and forgotten to reset the bed height before printing. good luck PEter

Quick (30min) dew strip check, clear with high drifting thin cloud, damp ground and breath condensation. Pointed the bins straight up into a nice cold patch of sky(-20C or so), extended dew shields and added a dew strip to one objective. Then waited…. No dew seen after 30min, but using my phone thermal camera shows a consistent 4-5C elevated temperature on the warmed objective. The unprotected one getting down to almost ambient temperature. Need to wait till we have a REALLY damp evening to see if I can get the unheated side to fog over. Peter

A few PLA materials I have do seem to develop “cracky” regions along their length, so they’ll break in the Bowden tube or by the feeder and fail the print. Bending the filament is fine apart from occasionally when it snaps. I’ve seen this on a block, red and blue, but others of the same colour are fine, so maybe a supplier/batch issue. Again I’ve only seen this rarely and the spare material ends up in the bin! If you’re using your machine enough the filament is unlikely to get affected. A colleague did have some ?7yr old material that he’d used in almost condensing humidity in Singapore... now very fragile. There are lots of PLA derived materials that claim better printing or better properties.... we are spoilt for choice. Peter

Leave the material in, it should turn off all the heating when it finishes a print. I have come across several machines with less than responsive controllers, just need to be patient with them. Looks like things are working as they should. I’d caution against making fine threads as they are not likely to work too well and light strip easily. peter

Get some distance from cities and big towns and see for yourself. https://www.lightpollutionmap.info/ will show you where you might get to, don’t worry about getting to totally dark, just outside the really bright bits. Should allow you to see the milkyway with no problems. Binoculars will reveal countless strings of stars. end of summer into autumn is best as the milkyway stretches overhead. I don’t get under those skies often and I am aware that “proper skies” can be another level “better”. The darker you go the easier it is to see stuff... of course remembering that the moon also ruins the views. good luck on finding somewhere dark. Peter

Putting a clip with some tissue on is useful to wipe crud off the filament prior to it getting fed in... reckon some random layer fails may have occurred before I did this peter

Heads up Prusa just announced a Mini version that’s simple to put together, but smaller build bed, 380 (ish currency units.... have to see what £). Available in a month or so... very interesting as that have a very strong reputation. PEter PS watched a colleague end a job today with millimetres of filament hanging out the extruder when it finished.... lucky?!

Steel or harder nozzles with the carbon fibre stuff, printed a block once and the whole end of my brass nozzle “vanished”... like ended up 3mm in diameter rather than 0.4mm. i never use rafts as they either don’t stick or stick far too well. I print onto the bed and use a brim that I can trim off. That way rectangular plates don’t peel off. I adhere with glue, though buildtak, hairspray etc are also good. For higher temp materials I like Dimafix... smells amazing too. With a 100C bed I can print ABS/PC/PVDF with no issues. Protopasta steel fill makes good weights too. Wood fill is only for those with infinite patience who have too many spare nozzles and like a challenge. peter

XTC 3D is like a gloss paint coat. Not checked how it improves strength, but PLA (as long as it’s not too thin) should be fine. For strength I use 6+ walls/ceiling/floor and then up the infill. If you can ant to tap threads then the extra wall thickness is needed. I have a colleague trying to “flame polish” PLA ti achivw the same result as acetone vapour smoothing does with ABS. He reports improved impact resistance (fewer rough bits to initiate cracks, but he’s seen some warping and bubbling...) PEter

Zoom sounds not so good. None of the major binocular companies make zoom binoculars (though they do make zoom eyepieces for spotting scopes). You’re likely to have quite a narrow field of view. Holding them steady could be hard at the higher powers. I am guessing they’ll have quite a narrow field of view. As with any optics, if you enjoy the views then keep them. PEter

Dry heat is best to get the moisture out. I used to recondition desiccant in an oven at 120C. PEter

I always over engineer things... maybe as I don’t have such delicate CAD skills as colleagues. If the part did start to degrade (not come across it myself) you could always run off another one. PEter

Colleague just got one and it seems to do the job well. Peter

Good in the daytime too. The more you can stabilise them the better. http://binocularsky.com/binoc_mount.php has some cheap and effective ideas. Also lying on the ground works well, especially for looking straight up where the skies are darkest. Most plants are visible, so willl plenty of star clusters and a good number of nebulae/galaxies (depends on your light pollution and object finding skills). God luck PEter