Starship Modeler Discussion Forums

The traditional way to get a laser to paint a circle is to shine it onto a mirror mounted at an angle on the end of a spinning motor - that way none of the laser assembly needs to spin. Shine the result onto another spinning mirror and you can create all sorts of cool lissajous patterns :) https://w...

Laser diodes are constant current devices like LEDs, but are far more sensitive to abuse. Whereas you can get by using a series resistor to limit the current on a low power LED, you're more likely to damage a LD using just a resistor due to operating changes whilst in use (e.g. temperature) These ch...

Yeah heat with hot water or hair dryer and straighten out. You can then "set" with cold water.

However if the original piece warped as the resin was setting up, you may find it returns to the warped state over time so it may be necessary to fix it down to somthing else to keep it flat!

Don't know if it's the same in Japan, but most car spray paints in the UK are acrylic based now, and work fine on vinyl.

Halfords is a chain of car parts stores here and their standard grey primer has been my staple kit primer for 20 + years.

You have to appreciate that when you buy any product from a commercial concern, you are not going to be paying just what the components cost. You also have to factor in the cost of initial design & development (could be many hours, days or weeks), the cost of obtaining the components, the cost o...

You've got some fairly serious issues with that circuit! Firstly, the switch is basically short-circuiting the battery when it's on (which will give you the impression it's off because the rest of the circuit will get no current). You need to put the switch between one pole of the battery and one le...

Being acrylic based, it tends to disintegrate if wet sanded, however dries really hard, so dry sanding can be a problem. Does dry quick though and useful for blocking in...

Have a look at Delrin or Acetal - a nylon-like material that is available as thick sheets in all sorts of sizes

What's more likely to be the issue here is the light output rating of the LEDs in question. Measured in candelas (cd) or milli-candellas (mcd) (1 cd = 1000 mcd) it can range from the dim end around 10 mcd up to hyper bright 10's of cd. As technologies have improved it's become possible to push out m...

The only time the lighting in my kits gets demonstrated is at shows, where there is usually no mains supply available so everything is designed to be battery powered. That means careful consideration over what is actually needed by the circuit, rather than taking what is available and burning off th...

Connecting a servo input directly to an output pin is ok because that does not directly drive the motor inside the servo, and so does not draw a lot of current. The servo electronics decodes the input signal, and converts & amplifies it into something capable of moving the motor to the appropria...

The Arudino pins never provide more than 500 mA of current, which is enough for a couple of leds, but no motor. At least not with a load to it. Just to call this out, the ATMEGA in the Arduino is rated at an absolute maximum of 40mA per output - and that does not mean it is safe to continually oper...

Ah that makes sense then!

And a creative solution!

Hey Chris- any reason you don't want to use batteries? The 3909 was specifically for low power drain circuits.... runs great on batteries.

Lost this in the recent outage, so posting again... I've just done a major redesign of my lighting board for the Pegasus Alpha UFO of this so that all the control electronics are now on the one PCB that drops into the saucer http://i113.photobucket.com/albums/n202/ants-nest/Kits/DSC_3372.jpg Full de...

It absolutely does not matter which side of the LED you put the resistor. If the LED is not lighting then there's something else wrong.

(+ve)-----WW---|>|-----(-ve)

is electrically eqivalent to

(+ve)-----|>|---WW-----(-ve)

(sorry about the ASCII art!)

Compatibles are functionally equivalent units not actually made by Arduino in Italy - since it's all open source, anyone can produce their own unit with identical behaviour, but usually the compatibles are 'expanded' in some way or another. The nano is a smaller version of the standard unit (i'm a b...

Mix a tiny bit of white acrylic paint into clear epoxy glue, then daub over the led. Instant diffusion!

Solid core wire is very prone to failure at anchor points (connections etc) if handled much. I'd always use multistrand if at all possible. If you can't find very thin stuff, try stripping down 2 core audio cable for headophones etc - you can usually find some nice stuff inside the braided screen la...

Yeah I'd agree it's most likey a bad connection - either a loose joint or possibly an intermittent short circuit...

As an aside, if you're using just LEDs why are you going all the way up to 9v only to have to drop it back down to the LED voltage? 4.5v should be fine, maybe 6v tops if you have some exotic white or blue devices with a high forward voltage. If you're looking for longevity, move up from AA to C cell...

You probably want a micro JST type connector like the ones at the top of this page http://www.jst-mfg.com/product/search_e ... =11&page=1

[Edit: Stupid sites with frames!]

Sorry for the lack of updates! I've now found a real job \:D/ so it's back to modelling! I now have a limited number of UFO lighting sets available. The price is 50 GBP +P&P for 1 set, or 90 GBP + P&P for 2 (Paypal ok for non-UK. Insured postage typically 10 GBP worldwide) Each set consists ...

Couple of things to remember... You're not buying from eBay, you're buying through eBay - they are just the gateway to connect you and the vendor. The quality of that vendor (and their goods) can rate from 100% to 0% Most semiconductor devices are made on large wafers that are cut up into individual...

A few helpful (hopefully!) comments In 30+ years of hobby electronics, I've never had an LED die in a correctly configured circuit. As long as it's operating within its spec, spontaneous death is _extremely_ rare and not something you need to factor into assembly. What is more likely is death from i...

Thanks all!

There will definitely be some available to buy - I have 7 more round PCBs - If I shift all them, I'll look into getting another batch made.

Small update on the UFO here http://www.antsnest.net/blog/?p=107

Been a bit busy with the 'real' job hunting....

I just posted an update with some video of the lighting module running

http://www.antsnest.net/blog/?p=97

I'm currently developing a lighting module for the Pegasus mini UFOs - can be used standalone with just a power source for static lighting, or coupled with my LED driver externally for animated lighting sequences.

More details on my blog

http://www.antsnest.net/blog/

Ant

I've had a lot of success with the board I produce - got a variety of applications now. There are some sample videos up on my web site here http://www.antsnest.net/LEDDriver.php

Keeping it simple and generic means its easy to adapt to all sorts of uses

Ant