Gavino200's Layout phase II - Modeling

[gavino200]

3 minutes ago, cteno4 said:

Man those are looking great Gavin! Beautiful smooth curves! There is a good reason you are a surgeon!

 

jeff

 

Honestly, I think surgery is easier than modeling. Maybe microsurgery comes close, but that's mostly the same thing over and over. The artistic side of modeling scares the hell out of me. In a way this was a good project to start off with because it's very technical (my comfort zone?). But I've learned quite a bit from it. Trying to make what goes over it look remotely like a city will be much harder for me. 

 

BTW, a specific question for you. There are 25 LEDs, each a 3mm LED. The power source is 5V. All will go on/off from one switch. I'll break them into a few sub-circuits, each with a resistor and a pot. How many sub-circuits do you think I need? ie, how many LEDs can I wire per resistor? I'm finished with my "wiring is fun" phase. 

[Kiha66]

34 minutes ago, gavino200 said:

 

Honestly, I think surgery is easier than modeling. Maybe microsurgery comes close, but that's mostly the same thing over and over. The artistic side of modeling scares the hell out of me. In a way this was a good project to start off with because it's very technical (my comfort zone?). But I've learned quite a bit from it. Trying to make what goes over it look remotely like a city will be much harder for me. 

 

BTW, a specific question for you. There are 25 LEDs, each a 3mm LED. The power source is 5V. All will go on/off from one switch. I'll break them into a few sub-circuits, each with a resistor and a pot. How many sub-circuits do you think I need? ie, how many LEDs can I wire per resistor? I'm finished with my "wiring is fun" phase. 

 

What is the current and voltage requirement for each LED?  Ideally one resistor per led is what should be used to ensure proper current levels than a single pot and switch can control the whole lot as a single unit.  LED wizard is a godsend for figuring out what resistors to use, assuming white LEDs 100 ohm is probably good for each light.  Wire each LED + resistor pair up in parallel, then use a single switch for the on/off function.  http://led.linear1.org/led.wiz 

Edited July 9, 2018 by Kiha66

[gavino200]

7 minutes ago, Kiha66 said:

 

What is the current and voltage requirement for each LED?  Ideally one resistor per led is what should be used to ensure proper current levels than a single pot and switch can control the whole lot as a single unit. 

 

It looks like max voltage 3-3.4 V. 

Max current 20mA

 

https://www.ebay.com/itm/100pcs-3mm-Transparent-LED-Water-Clear-White-Light-Diodes-Round-Top-Ultra-Bright/121729731850?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

 

I guess I could calculate it out. On my practice tunnel I just guessed and wired all three LEDs in parallel, and then in series with a 650 resistor and a high value potentiometer. 

 

Do you do calculations every time? How many LEDs to you wire together? Linking them in parallel and then adding resistors in series is the simplest wiring to do? Is this a no-no? 

Edited July 9, 2018 by gavino200

[Kiha66]

Here's what I got, you can just keep adding as many LED+resistor pairs as you like as a new branch each time.

Edited July 9, 2018 by Kiha66

[gavino200]

7 minutes ago, Kiha66 said:

Here's what I got, you can just keep adding as many LED+resistor pairs as you like as a new branch each time.

 

Thanks. So that's a resistor for each LED, with the calculated value deciding how many Ohms for each to keep them all safe. I could just add a resistor right at each LED leg. Then for potentiometers I could probably branch these down to a few "sub-circuits"? How many do you think? 5? 10? It's the potentiometer circuit and the number of pots to tune that I'd like to limit. I have pots in multiple values btw. On a previous project I started with low value pots, and had to go very high to get the full dimmer range from on to off. 

Edited July 9, 2018 by gavino200

[gavino200]

Thinking about it, I guess it doesn't really matter, as the LEDs would already be protected. I'd just have to experiment to see how many I can dim with one pot.

[Kiha66]

Sounds about right, you could do the whole thing with one pot if you wished as the LEDs are already at a safe power without it thanks to the resistors, and it should make dimming them all equally easier to do.

[cteno4]

Yep best to protect each led with a resistor. 

 

If you are putting a resistor in series (ie dropping resistor and a pot) then you need to calculate the power the big pot will need to dicipate for the subset leds/resistors.

 

actuallly for this application you probably don’t want Pots in there as you want all the leds the same. I would wire up a section with a few leds and just jump in resistors to the leds and Vary the resistors until you find the night level and just use that value for them all. It’s cheap to get a pack of like 25 value resistors and like 50 resistors of each on ebay. Or just grab a few different 100 packs of resistors at different values like $1 on ebay.

 

at 5v for white leds want to drop about 2v for a 20ma led so 100ohm will run it near the max. I think you will find you want it lower. So put a small 2k pot on an led and get it an idea I’d where it looks good on one. Then use a multimeter to read the resistance across the pot and you can test with 4 or 5 leds in a row with resistors nearest that value on each led.

 

Another option if you are using identical led is you can use a current limiting chip and run like 4 or 5 leds off this. Don’t need dropping resistors for these. You use a single resistor on the current limiting chip to set the current and thus brightness of the leds. 

 

cheers

 

jeff

[gavino200]

I posted a long but dumb electrical question here, but worked out my problem while re-reading the post. 

 

Move along - nothing to see here.

Edited July 13, 2018 by gavino200

[gavino200]

A little test. The first light shines.

 

I still have to correct the unevenness of the window edge just above and to the left of the light. 

 

 

Edited July 13, 2018 by gavino200

[chadbag]

I find LEDs frustrating to work out 🙂 LOL 

 

Thanks for going over this.  I was planning a guitar with LEDs in the fingerboard and also for decoration on the body.  PITA for a software guy to figure out.   Same with this sort of LED work.  

[Pauljag900]

In the five years or so I ve been doing this hobby I ve used a few diferent led types and styles.Most of the smaller LEDs usually come as 3v which obviously need a resistor if using a 12v supply.I always take the easy option and buy the power supply to suit the lights rather than mess about with resistors.Fitting dimmers is something I have nt done so can t offer an opinion I m afraid.

i think the most important part is not overloading the power supply.Most LEDs are rated at 20ma and there s 1000ma to an amp so a one amp supply will power 50:LEDs tho I usually do nt power any more than 40 just to be on the safe side.

i have three diferent power supplies connnected to my layout,3/6/12 volt and just connect the LEDs to the relevant supply.

just my two pennies worth gents,and believe me I ve blown up more than one power supply in this time!😂😂😂

[gavino200]

Ugly but functional wiring. The lights aren't this bright "in person". As usual, this took more than twice as long as expected. I swapped out resistor values with alligator clips and chose the one I liked best. Around 700 Ohms.

 

 

Edited July 14, 2018 by gavino200

[Kiha66]

That wiring looks pretty good gavin!  Much better than some "professional" jobs I've seen.

[gavino200]

All the main lights are in now. By the third segment, I was on quite a roll. I felt like I was working in a factory. I think I'll finish the electrics and try to adjust the window edge this weekend. I'm going to leave the interior detailing for next weekend. 

 

[Pauljag900]

Looks superb gavin👍😀

[gavino200]

On 6/17/2018 at 7:52 PM, cteno4 said:

Ha, you are hooked, you are going to have a full shop soon!

 

just to keep you mainlining here, this is another useful tool that dovetails nicely with the Saw! 

 

https://smile.amazon.com/WEN-6515-Belt-Sander-Sanding/dp/B01M68YKST/ref=sr_1_3?ie=UTF8&qid=1529283038&sr=8-3&keywords=1+belt+sander

 

jeff

 

Well, apparently it's "prime day". My wife asked me if there was anything I "needed" from Amazon. All I could think of was this. So.....

[Pauljag900]

And why not?😂😂😂😂

[cteno4]

Take the opportunity! While you can get stuff shaped ou with files and sanding blocks, s little guy is great as in a few seconds you can round things off or clean up edges pretty squarely. Is like the scroll saw, perfect to just try something really fast to fiddleman you seem to be doing a lot of fiddling. Get some finer grit belts to as it prime day!

 

Hook a little shop vac to it to keep dust down.

 

soon you will have to figure which car will live outside to make room for the shop in the garage, I’m sure it will be the one you drive...

 

Cheers

 

jeff

[gavino200]

3 hours ago, cteno4 said:

 

Hook a little shop vac to it to keep dust down.

 

 

Hmm, a shop vac. That might also be something for Prime Day. My wife complains  a LOT about me generating dust in my workroom (which is also her washroom). Especially a big issue when I'm sanding plaster. 

 

Can you recommend one?

 

Edit: Is a "shop vac" just a regular vacuum cleaner? I guessed they'd have some mechanism to sort of hover over what you're doing to prevent a mess. 

Edited July 16, 2018 by gavino200

[cteno4]

Shop vacs are usually just a can with the motor on top so you can just pull off the motor and dump the big can. Some can also vacuum water (wet/dry) if you put a filter over the regular filter. They usually don’t use bags so you get the power to suck up a cat. Usually not hepa level filtration but not going to get full suction thru a bag and hepa filter but much better than no bag. They are also louder than regular vacuums but again needed for the cats.

 

size is also an issue small ones are not so loud and can pick up the small and medium stuff, but bigger ones are of course great at sucking up large amounts and pull the cats from further across the room. Smaller ones have the standard house vacuum 1.25” hoses and attachments, bigger ones use 2.5” hoses and attachments. These are very bulky. I have both little and big one. I don’t use the big one much anymore as the big dust handler deals with most of that and the little one is smaller and easy to hook up next to the drill press or attach to band saw or quickly clean up the bench or table saw. I use the big one only now if a big mess on the floor and even then I’m questioning if I need to keep it with the space it takes up but it’s got amazing suction!

 

For just some stuff around the layout room, your scroll saw and sander a smaller one would do fine. Won’t have super suction but fine to clean up stuff and hook to the sander or saw. I got this one last year and it’s holding up well. Not a super sucker but for this size and price you are not going to get a cat sucker. It’s gone up a bit in price in the last year. Most seemed about the same in reviews this one was just more compact as it’s going to live under the drill press rollaround.

 

https://smile.amazon.com/gp/product/B0023EY002/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

 

if you are doing sanding and such in the house and around the layout I would also recommend having a hepa air filter in the room going all the time as they get the fine floaty stuff that ends up getting all over the layouts, in locos etc. great for helping control plain old dust as well. My wife has dust allergies so we have a few of these around the house to suck up schmutz and I’m always shocked how much they trap. Foam prefilter changednonce a month that grabs the big dust and you can vacuum to reuse or buy it in bulk to cut your own very cheap. Main filter changes once a year not cheap.

 

https://smile.amazon.com/gp/product/B00BWYO3EM/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

 

more inexpensive ones out there as well, these just have a good reputation and have done well now for 4-5 years for us now.

 

the scroll saw was just a gateway...

 

cheers

 

jeff

[gavino200]

22 minutes ago, cteno4 said:

 so you get the power to suck up a cat. 

 

🤣 That's funny! Made me chuckle. We have two cats. I can just imagine them getting sucked into this thing!

 

22 minutes ago, cteno4 said:

 

size is also an issue small ones are not so loud and can pick up the small and medium stuff, but bigger ones are of course great at sucking up large amounts and pull the cats from further across the room. Smaller ones have the standard house vacuum 1.25” hoses and attachments, bigger ones use 2.5” hoses and attachments. These are very bulky. I have both little and big one. I don’t use the big one much anymore as the big dust handler deals with most of that and the little one is smaller and easy to hook up next to the drill press or attach to band saw or quickly clean up the bench or table saw. I use the big one only now if a big mess on the floor and even then I’m questioning if I need to keep it with the space it takes up but it’s got amazing suction!

 

For just some stuff around the layout room, your scroll saw and sander a smaller one would do fine. Won’t have super suction but fine to clean up stuff and hook to the sander or saw. I got this one last year and it’s holding up well. Not a super sucker but for this size and price you are not going to get a cat sucker. It’s gone up a bit in price in the last year. Most seemed about the same in reviews this one was just more compact as it’s going to live under the drill press rollaround.

 

https://smile.amazon.com/gp/product/B0023EY002/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

 

if you are doing sanding and such in the house and around the layout I would also recommend having a hepa air filter in the room going all the time as they get the fine floaty stuff that ends up getting all over the layouts, in locos etc. great for helping control plain old dust as well. My wife has dust allergies so we have a few of these around the house to suck up schmutz and I’m always shocked how much they trap. Foam prefilter changednonce a month that grabs the big dust and you can vacuum to reuse or buy it in bulk to cut your own very cheap. Main filter changes once a year not cheap.

 

https://smile.amazon.com/gp/product/B00BWYO3EM/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

 

more inexpensive ones out there as well, these just have a good reputation and have done well now for 4-5 years for us now.

 

Thanks for the rec. A vacuum would be nice. And a filter some day. It's not urgent. The train room is completely separate from the workroom. Plastered ceiling, tiled floors, dehumidifier, windows permanently shut. Door always closed to keep out Catzilla.

 

22 minutes ago, cteno4 said:

 

the scroll saw was just a gateway...

 

 

It seems you may be right. Though, I don't think I'll ever get a table saw or a circular saw. Maybe, some day I'd get a "Saw Stop". But until then it's the hand saw for me. But a drill press....Hmmm. Maybe. 🙂 

[cteno4]

A shop guy I worked with when I was young use to rate the various vacs in the shop by how many cats they could suck up! Funny but scary when you put a big open end of a large shop vac hose on the bench near tools and watch them get sucked up!

 

It is amazing how much dust the air cleaners pick up. It’s helped a lot In the basement and I have the ceiling sealed up there. I have high merv on both central hvacs and no carpet and vacuum a fair amount. But we live in a forest so we get lots of fine crap raining down from the trees, mold spores fro leaf litter and soot from the highway after mile away.

 

yes drill press is the next obvious shop tool for your fiddling! Even a cheap small one on sale for $50-100 would do you fine for now and don’t take up huge amount of space!

 

jeff

[gavino200]

Adding in the "pipes and cables" took a long time but went smoothly. That was a LOT of buttons to sew!

 

I ran out of Tamiya masking tape last night, and picked some up at the local art store this morning. I was surprised to find that - for this purpose - the generic art store tape was much better. So much so that I took down the Tamiya tape and replaced it.

 

I'm using a different expandable foam that I haven't tested. Supposedly less messy and less over-expansion. It was easy to work with and to clean up, but I'll have to wait and see how well it works. 

 

I took the masking pretty seriously after having experienced the horror of "Great Stuff". I probably overdid it a bit as this material is much more benign. I also put a layer of wax paper between the fascia/layout and the foam. I'm hoping the foam will stick to the tunnel but separate from the fascia and layout, so as to lift out as one piece with the tunnel segment.

 

The window still needs some tweeking.

 

 

 

Edited July 23, 2018 by gavino200

[gavino200]

So finally the round tunnel is finished. The end fascia needs to be re-done due to a miscalculation. And a couple of catenarys need to me adjusted. Also the "signal" lights aren't wired to a switch yet. But I'm very relieved to have this project behind me.