Search found 564 matches
- Sat Aug 18, 2018 3:14 pm
- Forum: Lighting & Electronics
- Topic: DC from one supply works, but not the other?
- Replies: 8
- Views: 25146
Re: DC from one supply works, but not the other?
The problem with that is that the circuitry is inaccessible right now. But these batteries should be powering it. They're brand new and producing a strong 18+ volts which is stepped down to 12.3VDC by the voltage divider. I tested them with my DMM like I said, and they produce the correct voltage. T...
- Sat Aug 18, 2018 1:21 am
- Forum: Lighting & Electronics
- Topic: DC from one supply works, but not the other?
- Replies: 8
- Views: 25146
DC from one supply works, but not the other?
So I've been using an AC-DC converter to test the circuitry in my USS Enterprise-D built for a customer. I have used this unit before to test other circuits, and so far it's been just fine as a substitute for a battery power supply. But for some reason, I can't get the batteries in the base of the m...
- Sat Aug 11, 2018 7:31 pm
- Forum: Finishing
- Topic: How to lift a dried decal for repositioning?
- Replies: 4
- Views: 19055
How to lift a dried decal for repositioning?
I have a minor emergency. The main registry number decal for my USS Enterprise-D model is positioned too far down the nose of the ship. I hadn't painted the windows yet so I didn't know that it was over them until I was putting on the transporter pads. Is there a way to maybe soak the decal with war...
- Tue May 15, 2018 4:35 pm
- Forum: Lighting & Electronics
- Topic: In search of a variable rate strobe circuit
- Replies: 3
- Views: 20005
Re: In search of a variable rate strobe circuit
Definitely the 555 timer is a great, simple little device to get a strobe to flash. Just remember to hook up a diode across the timing resistor, like in this diagram: https://electrosome.com/wp-content/uploads/2012/11/555-timer-astable-multivibraotr.jpg If you don't, it won't be a strobe because the...
- Tue May 15, 2018 4:31 pm
- Forum: Lighting & Electronics
- Topic: Reducing LED Brightness?
- Replies: 12
- Views: 38022
Re: Reducing LED Brightness?
Yeah, another vote for the trimpot. And I would add, after you're done adjusting it, it might be good to put a drop of paint on the knob so that it doesn't move as you're assembling the model. They can be easy to knock around, so I figure that little bit of insurance can't hurt. :) Alternatively, yo...
- Tue May 15, 2018 4:28 pm
- Forum: Lighting & Electronics
- Topic: Using a microcontroller to charge a NMH battery?
- Replies: 3
- Views: 15838
Re: Using a microcontroller to charge a NMH battery?
Thanks for the link! It was a really good read and a big help with this project.
- Thu May 03, 2018 3:49 pm
- Forum: Construction
- Topic: Glue for mounting LEDs
- Replies: 4
- Views: 16937
Re: Glue for mounting LEDs
Epoxy is great stuff. Though sometimes I use superglue anyway because it actually doesn't fog the LED in a meaningful way unless you get it on the lens.
- Sat Apr 28, 2018 9:36 pm
- Forum: Lighting & Electronics
- Topic: Using a microcontroller to charge a NMH battery?
- Replies: 3
- Views: 15838
Using a microcontroller to charge a NMH battery?
I have a large project that has need of an independent power supply for one area, and I was thinking about using a microcontroller to switch off the main power when the NMH battery is fully charged. Something like telling it "if v=12 disconnect power, else connect power to batteries" to ma...
- Sun Aug 27, 2017 12:28 am
- Forum: Lighting & Electronics
- Topic: Why is my 555 timer not blinking?
- Replies: 30
- Views: 374334
Re: Why is my 555 timer not blinking?
I'd also like to remind everyone how easy this is with a Microcontroller like Arduino: You can set those two values however you like. There's no restriction on the duty cycle as there is with a 555, and you don't need to rewire your circuit if you change your mind about the flash rate or duty cycle...
- Wed Aug 23, 2017 5:51 pm
- Forum: Lighting & Electronics
- Topic: Why is my 555 timer not blinking?
- Replies: 30
- Views: 374334
Re: Why is my 555 timer not blinking?
Hmm... a new problem seems to have emerged. I thought I could simply put a diode across R2 and that would cause it to strobe rather than have a >50% duty cycle. Well, none of the diodes I've tried have worked. I used a 1N4004 and a 1N485A, plus a couple more that I found in the parts bin. It still h...
- Tue Aug 22, 2017 5:41 pm
- Forum: Lighting & Electronics
- Topic: Why is my 555 timer not blinking?
- Replies: 30
- Views: 374334
Re: Why is my 555 timer not blinking?
I think you miscalculated your RC time and you have an LED blinking at too fast a rate for the eye to detect. I think your off blink time is about 10 msec. I suggest increasing your resistor and or capacitor values to get a longer RC time. Turns out you were right! I had been calculating it on the ...
- Sun Aug 20, 2017 12:47 pm
- Forum: Lighting & Electronics
- Topic: Why is my 555 timer not blinking?
- Replies: 30
- Views: 374334
Re: Why is my 555 timer not blinking?
You might be right about the miscalculation. I'll rework it and see if I can find a configuration that works. You're thinking of a monostable configuration if you think it needs an exterior trigger to fire. The monostable configuration will only fire once. The astable configuration will oscillate on...
- Sat Aug 19, 2017 6:05 pm
- Forum: Lighting & Electronics
- Topic: Why is my 555 timer not blinking?
- Replies: 30
- Views: 374334
Re: Why is my 555 timer not blinking?
Additional thought. Are you trying to make a strobe blink? I use a signal diode in parallel to r2 for strobing, which gives the short duty cycle. No diode if just going for a nav light cycle. Yeah, hence the 1N4004 (It's a 1N4004, not 4005, btw). I want a strobe, not a nav light. Without looking at...
- Fri Aug 18, 2017 10:34 pm
- Forum: Lighting & Electronics
- Topic: Why is my 555 timer not blinking?
- Replies: 30
- Views: 374334
Why is my 555 timer not blinking?
I built a 555 timer in an astable multivibrator configuration. I checked all the connections and it looks like it's hooked up right, but when I apply power the light just stays on instead of blinking. This is a common problem I have with this type of circuit, but I'm not sure what causes it or how t...
- Fri Mar 24, 2017 1:36 am
- Forum: Construction
- Topic: Got Resin?
- Replies: 53
- Views: 181824
It'll have to be a two-part mold, I'm afraid. I'm copying an old engine dome for the Enterprise kit, and it is a rather complex shape. I'm thinking about simply coating the interior of the cavity with degassed epoxy and then pressing the two halves carefully together to make a whole part. The part d...
- Thu Mar 23, 2017 6:20 am
- Forum: Construction
- Topic: Got Resin?
- Replies: 53
- Views: 181824
- Thu Feb 16, 2017 12:07 pm
- Forum: Lighting & Electronics
- Topic: Remote power for a removable module?
- Replies: 5
- Views: 9829
- Wed Feb 15, 2017 9:03 pm
- Forum: Lighting & Electronics
- Topic: Remote power for a removable module?
- Replies: 5
- Views: 9829
Part of the problem with this is that the surfaces of the saucer and battlehead don't physically touch except on three standoffs. I could put wires through them, though. There are three, which could be the ground, +VCC, and strobe light control. I could also put in a magnetic reed switch to switch f...
- Wed Feb 15, 2017 12:32 am
- Forum: Lighting & Electronics
- Topic: Remote power for a removable module?
- Replies: 5
- Views: 9829
Remote power for a removable module?
So I'm working on the USS Enterprise-D, and naturally my client wanted the saucer section to be lit independently of the model... So I was wondering if the idea I had would work. I don't want the electrical contacts to be visible. Could I use a cell phone induction charger in the battle head to char...
- Tue Feb 14, 2017 8:43 pm
- Forum: Construction
- Topic: MEK-dissolved styrene filler?
- Replies: 12
- Views: 25830
Thanks for all the input, guys. The reason I would rather use MEK than solvent-based welders is that it's cheaper. I can get a big can of it at Walmart for $4 vs. the $5 it costs to get a bottle of Ambroid or something. If drying time is really the only big disadvantage, then I think that will be fi...
- Fri Feb 10, 2017 8:11 am
- Forum: Construction
- Topic: MEK-dissolved styrene filler?
- Replies: 12
- Views: 25830
- Fri Feb 10, 2017 6:56 am
- Forum: Construction
- Topic: MEK-dissolved styrene filler?
- Replies: 12
- Views: 25830
MEK-dissolved styrene filler?
So I am going to be building the SFSM Survey class vessel, and I was wondering how good or bad an idea it would be to chop up some of the scrap plastic left over from cutting out the parts, dissolving it in some MEK, then putting it in the oversized panel lines all over the model?
- Fri Nov 11, 2016 7:33 pm
- Forum: Scratchbuilding
- Topic: What to look for in a desktop laser cutter?
- Replies: 13
- Views: 25053
What to look for in a desktop laser cutter?
I'm going to buy one of these fairly soon. My budget is $500 or less, and I need the machine to be able to cut through 060-080 gauge sheet styrene. But I don't have a clue what I'm looking for... I would hope it would come with software, too. So what would you guys recommend?
- Wed Nov 02, 2016 4:14 pm
- Forum: Construction
- Topic: How to make photoetch parts with multiple layers of detail?
- Replies: 3
- Views: 9896
How to make photoetch parts with multiple layers of detail?
So there was a really good video on making photoetch posted here a while ago, and I've been thinking about using it to make some detail parts for the Zvezda Star Destroyer kit (mainly the hangar crane and some ribbed detail for the edges of the engine bank). But it only explains how to do simple par...
- Tue Sep 27, 2016 7:14 pm
- Forum: Lighting & Electronics
- Topic: Lighting a 350 Refit
- Replies: 5
- Views: 10265
- Sat Sep 17, 2016 10:06 pm
- Forum: Finishing
- Topic: Metalizers and sealing coats
- Replies: 2
- Views: 5917
- Sat Sep 17, 2016 2:21 pm
- Forum: Finishing
- Topic: Metalizers and sealing coats
- Replies: 2
- Views: 5917
Metalizers and sealing coats
So I did some experimentation with Model Master buffable metalizer paints for a client's build, and while the paint looks awesome after you buff it, when I sprayed it with Testor's metalizer sealer, they ended up looking like I hadn't buffed them at all. Buffable metalizers are really delicate thoug...
- Thu Sep 15, 2016 9:45 pm
- Forum: Plates In Space Challenge
- Topic: Who's ready for a new Challenge Build?
- Replies: 77
- Views: 314039
- Sun Sep 04, 2016 2:47 pm
- Forum: Scratchbuilding
- Topic: Excellent PE demo video
- Replies: 3
- Views: 10689
- Wed Aug 17, 2016 12:40 pm
- Forum: Lighting & Electronics
- Topic: Shouldn't 12v be enough for seven 3mm LEDs?
- Replies: 31
- Views: 48852
Well, it depends on how the LEDs are being hooked up. I can't imagine 12V not being enough to power them all in parallel, because they only need about 3.5V each and in parallel, current is what varies, not voltage. I can see the LED tester testing them all in parallel because this will eliminate the...