markse68

Thanks very much Rory- what a quirky and interesting design! Looks great! I wonder what kind of ribbon it is- you'd think it'd stretch and loosen over time? Guess not- looks pretty taught. Does it hold the secondary solidly? Agree on it being a much nicer mechanism than the simple 3 screws

Hi Rorymultistorey, got any pics?

Could it just be the laser collimator shifting in the ep tube?

I was looking at that handle thinking it looked a bit uncomfortable until I realised it’s a picatinny/weaver rail for a rdf- nice touch 👌 I wondered why there weren't many harmonic drive mounts about. I guess price and maybe torque ripple- though with decent control that shouldn’t really be an issue? And now the Chinese are making decent quality ones since the patent expired they seem ideal 👍 Surely you’d want to balance it though- they’re backdriveable and the motor’s going to be taking the load?

Cheers Stu- the solder joint itself looked alright too haha I think I need to make a thin walled steel former and hope it doesn't solder itself to it next time- need something in there to keep the shape nice and accurate while soldering edit- dunno why I didn't think of it before- a pair of SS mudguard washers turned to dimension spaced on a bolt should do it- shouldn't stick to the solder either

Ballcocks! 😞 Well you learn something new every day and I learnt today that you shouldn’t use aluminium formers to silver solder brass... It started off so well as well Guess I’ll be starting that again from scratch- ballcocks

Spider completed using some 0.5mm SS sheet- I could really do with some new tin snips as it was a [removed word] to cut. Bit rough but I think it’ll do. Just the mirror support cowl to make now

Moved it to D6- that did the trick. think it should be strong enough 30D8DFF2-43AC-478B-AA75-B980CEC1CC78.MOV

Doh- should have read the description properly: “The Arduino NANO Every has the standard ADC and PWM resolutions of 10-bits and 8-bits, respectively. This board doesn't have PWM on D11 and therefore it supports only 5 PWM outputs, as on the Arduino UNO WiFi Rev.2. “ and guess which pin I used for the LED- yep- D11 🤦‍♂️ Still good to know why it’s not working and should be easy enough to fix

Finally bit the bullet and knuckled down to wiring the handpiece- really made a rod for my own back though with the very tight space for the wires...it’s going to be really tricky getting the other half of the housing on there without squashing wires 🤦‍♂️ But it works-almost perfectly-almost that is except the pwm on the LED isn’t pwming 🤔 I swapped from a nano to the new Arduino nano every and I’m guessing the code isn’t totally compatible... 0E01F364-3061-4211-904D-1334A76EFE8A.MOV

Does gravity really cancel out like that? So in this classical interpretation you could float out of the zero gravity interior of the hollowed out planet through a tunnel that the excavators had conveniently left and instantly feel normal gravity when you emerged onto the outer crust?

Really puts the hugeness of our star into perspective- such a tiny planetary spot compared to say Io’s shadow on Jupiter! But then you see this 😳

Not happy with the weight of it all and the poor rushed assembly I pulled it apart (that retaining compound is really tough- took an hour in a 250degC oven to soften it up enough to crowbar it apart!) I made new plates 4mm thick instead of 6, shortened the pillars and remade the locking piece in aluminium instead of brass- reducing the weight by almost a quarter Much happier with the way it went together this time I also lightened other parts and swapped the stainless screws for Ti for an overall weight saving of 62g- it feels much lighter now I've also prepared the former for the mirror support tube- to be made form thin brass sheet

Don’t know the answer to your question except increasing secondary obstruction reduces contrast I think 🤔 Protostar have 1” quartz mirrors https://www.fpi-protostar.com/quartz.htm edit- out of stock 🤦‍♂️

And it won’t rust of course

I bought a lilo footpump from Tesco’s during the summer. Yet to use it in earnest but hoping it’ll do the trick. Need to make a fine nozzle for it first though. I reckon it should give a good high pressure jet of air for sustained blowing of dust, I don’t really like the little hand squeezy blowers and like you say the cans have a habit of squirting liquid content. It’s got a nice long tube so should be pretty dexterous. No idea about that powered blower though it looks a bit ungainly 🤷‍♂️

AKA the pencil sharpener 😉 All ready for the hand-controller...

No don’t thank me- I was bidding against you (I think) 😬 Glad it went to a good home though 😉 Mark

Ah- so it was you haha 😂 congrats! I can’t be too dissappointed though- picked up a bargain oiii 1.25” myself the same day (if I’m right 😉) which I’ll actually be able to use- can’t wait for first look at the veil should the clouds play nice 👍

Hi skybadger, No I didn’t- the motor is very easy to back drive when de-energised so I’m just going to fit a another knob to the other end of its shaft for manual use. Also a clutch holds very tight so I’d lose the misalignment tolerance which this has.

Initially I planned to make the focus motor quick release and the magnetic coupling made some sense but I ended up going for a simple screw mounted motor so it makes less sense now 🤔 But it’s done now and it works really well- better than I’d expected. It allows for lateral misalignment yet is a nice stiff rotational coupling for the sort of torque required to turn the moonlite knob. A ptfe pad keeps the magnets slightly separated so the two plates can move a little easier against each other. The black magnet holder on the focus knob is 3D printed and a press fit on the knob

Where’s the elephants trunk? I m finding myself fascinated by the dark areas in many nebulae- is there an explanation for them?

I had to wait an unbearably long time but the 3D printed housings arrived this week and they look great 👍 Surprisingly everything fits- a bit snug but it fits! I’d hoped to get the handset all soldered up today but wasted too much tome shopping so I’ve just been staring at it- psyching myself up to it and trying to plan the best way to wire it- it’s a tight fit and I don’t want to screw it up. The little round pcb is a reverse polarity protection pcb I built for something else that also used li-ion batteries...which is handy 😉 The battery cap still needs milling.

Just came back from Munich to find these- 3D printed parts for my scope 😃

Thanks Vlav, I get the wave cancellation bit but it was the “ so it doesn’t reflect in first place” leading to increased transmission that I don’t get. But I think what you’re saying is the wave function cancels so the probability reduces of the photon appearing after the “reflection” and increased probability of it being transmitted? 🤔