2020 Goals - Soldering an Eggfinder

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SecondRow

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So I picked up a LOC Norad Pro Maxx recently - I like the look (I like transitions). It looks like this will be a good rocket to fly on our non-waiver field with F and G motors, and also something I can take to our smaller HP field for H and I fun. If it flies well on those, I might try for level 2 on a J at our big field next November (Goal #1). OR is predicting an altitude of around 4400 ft.

I can hear some of you now: "SecondRow, don't go so high for your L2 flight! Use big, dumb 4" rockets, not a light 3" rocket that transitions to 2.26"! You're being foolish." Probably, but I'm comfortable using my JLCR (my L1 was to 2800 ft with the chute release), and this should be fun. I also plan on using a tracker. Researching the different options, I decided I want to build an Eggfinder (Goal #2). But there's just one sticking point, I've never soldered anything before. So, I need to learn (Goal #3 - probably should have been Goal #1) if I want this to work right. Plus, it's time to learn a new skill.

And that's what this thread is going to be over the next couple months: learning how to solder, improving my skills, getting you guys to critique my work. All for the end goal of trying to build the Eggfinder. Also, a place to put any information I find elsewhere that I think will come in useful down the road. Oh, and a place to ask lots of stupid questions. :headspinning:

First up is a couple threads I found and liked:
https://www.rocketryforum.com/threads/eggfinder-tx-rx-and-eggtimer-quark-assembly.144041/
https://www.rocketryforum.com/threads/eggfinder-pictorial-build.121027/
https://www.rocketryforum.com/threads/solder-pencil-for-eggfinder.68539/

Edited to add another thread I found: https://www.rocketryforum.com/threa...-circuit-board-soldering.156492/#post-1944502
 
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First couple questions are Eggfinder specific. I want to make sure I understand the system. I know I could ask EggTimer, but since I don't plan on buying the kits for a couple months, I didn't want to bother them at this point. So this is a way for me to remember these questions down the road. But if anyone (especially cerving) wants to answer, I'll be grateful.

1. I know I need the Tx. The question is which receiver assembly to get. As far as I understand, to get the coordinates from the Rx I would need a laptop or an android phone. Am I correct?

2. If that’s the case, I will probably get the LCD receiver. I’ve got an iPhone and don’t have a laptop other than my work computer. I don’t think corporate security would appreciate the situation, so I’ll get the LCD.

3. With the LCD, I would have to plug the coordinates into my phone, right? And if I get the GPS module add-on to the LCD, then I don't need my phone. The LCD will tell me where to go, correct?
 
First couple questions are Eggfinder specific. I want to make sure I understand the system. I know I could ask EggTimer, but since I don't plan on buying the kits for a couple months, I didn't want to bother them at this point. So this is a way for me to remember these questions down the road. But if anyone (especially cerving) wants to answer, I'll be grateful.

1. I know I need the Tx. The question is which receiver assembly to get. As far as I understand, to get the coordinates from the Rx I would need a laptop or an android phone. Am I correct?

2. If that’s the case, I will probably get the LCD receiver. I’ve got an iPhone and don’t have a laptop other than my work computer. I don’t think corporate security would appreciate the situation, so I’ll get the LCD.

3. With the LCD, I would have to plug the coordinates into my phone, right? And if I get the GPS module add-on to the LCD, then I don't need my phone. The LCD will tell me where to go, correct?

@cerving is active here and may weigh in.
 
Correct. Either transmitter with the LCD receiver and GPS module will get you what you want. When you get ready, call the company and talk to them. You will need a data cable also. cerving is the boss on this. :)
 
Next up is equipment related. What to buy to get started practicing. From reading the EggFinder instructions and the TRF threads, it seems like I need:

1. an iron that capable of variable temperatures, with a small conical tip.
2. a brass sponge.
3. good tweezers
4. A magnifier (about 10x)
5. A good light source
Edited: 6. A solder wick
Anything I'm missing?

I was thinking about spending in the $30-$40 range for a soldering station. Is this is a good choice? It has a temp range of 200-480° and comes with a 0.2mm conical tip: https://www.amazon.com/Aoyue-Variable-Soldering-Station-Removable/dp/B00MCVCHJM
 
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No experience with that soldering station, so no opinion. You will need additional soldering tips, some good solder like Kester brand, flux and pretinner is a good thing to use. Magnification for assembly is the subject of discussion. Depends on your eyes I suppose, but most suggest lower magnification for assembly (2-4X give or take) and higher mag (10-20X for inspection). Some with young eyes use no mag for assembly so YMMV. ;)
 
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These things make building eggfinder a lot easier for me:
+MAGNIFICATION - I use an old stereo microscope that was headed for the dumpster at work.

+ Good soldering station. I think this one is the best buy under $200. https://www.microcenter.com/product/456476/hakko-70w-digital-soldering-station. I'm sure there's wun hung lo knockoffs on eBay for cheap. I do the SMDs with a cheapo eBay hot air soldering station. https://www.amazon.com/dp/B01MR2IWBN/ref=cm_sw_r_cp_apa_i_uN29DbQW9HMPV

+Board holder. Just makes it easier :) https://www.microcenter.com/product/603900/elenco-adjustable-circuit-board-holder

+ not RoHS solder paste in a syringe. eBay special.

+TWEEZERS. eBay special set - a couple of them since they're cheap, small and easy to loose.

+ spare soldering iron tips (I grabbed a set of 9 different shapes & sizes) solder wick, flux, cheap spring loaded solder sucker, xacto knives, etc....

+ helping hands. Great for holding wires while soldering. https://www.microcenter.com/product/391345/eclipse-enterprise-helping-hands-soldering-aid
 
3. With the LCD, I would have to plug the coordinates into my phone, right? And if I get the GPS module add-on to the LCD, then I don't need my phone. The LCD will tell me where to go, correct?
Correct. Either transmitter with the LCD receiver and GPS module will get you what you want. When you get ready, call the company and talk to them. You will need a data cable also. cerving is the boss on this. :)
The LCD also has a Bluetooth option which will allow you to connect it to a phone/tablet. That data link can feed an app like "Rocket Locator" to give you a map with the location of your rocket.
 
First couple questions are Eggfinder specific. I want to make sure I understand the system. I know I could ask EggTimer, but since I don't plan on buying the kits for a couple months, I didn't want to bother them at this point. So this is a way for me to remember these questions down the road. But if anyone (especially cerving) wants to answer, I'll be grateful.

1. I know I need the Tx. The question is which receiver assembly to get. As far as I understand, to get the coordinates from the Rx I would need a laptop or an android phone. Am I correct?

2. If that’s the case, I will probably get the LCD receiver. I’ve got an iPhone and don’t have a laptop other than my work computer. I don’t think corporate security would appreciate the situation, so I’ll get the LCD.

3. With the LCD, I would have to plug the coordinates into my phone, right? And if I get the GPS module add-on to the LCD, then I don't need my phone. The LCD will tell me where to go, correct?

With just the LCD, you can get distance and bearing from the pad plus current lay-long if you add a button (directions tell you how). That’s enough to find the rocket in most cases though the GPS add on is also nice.
 
I'll go in a different direction as far as suggestions. I bought a cheap soldering station from amazon and a very cheap iron with a conical tip (non-variable). The solder that came with the Eggfinder was plenty to complete the task. Tweezers were a must, but any cheap set will do. That's it.
More important (to me anyway) was to watch the videos, read the directions several times, and remember to take frequent breaks. Keep a clean work area too, those little bits disappear easily.
 
First couple questions are Eggfinder specific. I want to make sure I understand the system. I know I could ask EggTimer, but since I don't plan on buying the kits for a couple months, I didn't want to bother them at this point. So this is a way for me to remember these questions down the road. But if anyone (especially cerving) wants to answer, I'll be grateful.

1. I know I need the Tx. The question is which receiver assembly to get. As far as I understand, to get the coordinates from the Rx I would need a laptop or an android phone. Am I correct?

2. If that’s the case, I will probably get the LCD receiver. I’ve got an iPhone and don’t have a laptop other than my work computer. I don’t think corporate security would appreciate the situation, so I’ll get the LCD.

3. With the LCD, I would have to plug the coordinates into my phone, right? And if I get the GPS module add-on to the LCD, then I don't need my phone. The LCD will tell me where to go, correct?

I recommend the LCD receiver, it's WAY easier to use, and it saves your coordinates in case you lose power. If you go Bluetooth/USB and you lose the connection (and it DOES happen... for a number of reasons) then you've lost your coordinates and your rocket. All you have to do is plug the coordinates into a navigation app on your phone (like MotionX on the iPhone) and tell it to "take me there".

There are also some cool accessories for it, but you can read about that on the web site. If you get the GPS module, you don't even need a phone/tablet/laptop... it will point you to the rocket and tell you how far away it is from you. Just follow the arrow and it will take you right to it.

Eggtimer Cris
 
Before you start on any of the eggfinder products some practice on a gikfun project like this https://www.amazon.com/gp/product/B00VWB8F8K/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1 will hone your soldering skills. The first thread you listed is a good guide.
I bought the gikfun practice kit a couple of weeks ago when I bought a Quark. The gikfun was helpful but today I built the Quark and it was substantially more difficult than the gikfun. I did get the Quark working despite 3 unfortunate bridges, my first surface mount project ever. I've heard the Eggfinder is harder. Good luck!
 
I haven't done the Eggfinder, but the Quantum went together very quickly. Sometimes it really helps if someone can show you some of the techniques to surface mount soldering. Most of the times that I've seen people struggle soldering, it's simply from not understanding how the heat distributes, what cold solder joints look like, how much solder to use, etc. Things that can be learned very quickly with an experienced person showing you. What region are you located?
 
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Another item that’s generally overlooked in this discussion about soldering is a fume extractor. For those people who might be a little sensitive to these fumes, asthmatics, etc, this might be a good addition to their station. Although lead-free solder is in common use these days, the flux can still produce some irritation. These extractors have charcoal filters that can be replaced periodically.
 
Correct. Either transmitter with the LCD receiver and GPS module will get you what you want. When you get ready, call the company and talk to them. You will need a data cable also. cerving is the boss on this. :)

Stupid question #1: What's the data cable for?
 
I haven't done the Eggfinder, but the Quantum went together very quickly. Sometimes it really helps if someone can show you some of the techniques to surface mount soldering. Most of the times that I've seen people struggle soldering, it's simply from not understanding how the heat distributes, what cold solder joints look like, how much solder to use, etc. Things that can be learned very quickly with an experienced person showing you. What region are you located?

I'm in Atlanta. I think this is a good idea. I've been watching videos, but I still really can't tell what a cold solder joint is, what a dry solder joint is, or what a good joint looks like. My wife reminded me last night that there is a maker space only a few minutes from our house. The membership is $25/month. I might join and see if anyone there can give me advice.
 
Revised materials list (I can't edit the original post anymore), thanks to your suggestions:

1. an iron that capable of variable temperatures, with a small conical tip (+ extra tips).
2. a brass sponge
3. good tweezers
4. A magnifier ( 2-4x for assembly, 10x for inspection)
5. A good light source
6. A solder wick, solder sucker
7. solder, flux, pretinner (Kester)
8. anti-static mat
9. fume extractor

Not sure I'll get everything on the list at first. Depends on cost and the space I have available. I'm currently frozen by the paradox of choice for the iron. I think I've watched dozens of youtube videos on soldering stations.
 
Stupid question #2: I've seen it suggested to use a small conical tip. But what's "small" in this case? The smallest I've found is 0.2mm on Amazon - is that small enough? Or do they come smaller?
 
Stupid question #1: What's the data cable for?
You will need the 3-wire cable for (re)programming the Tx module frequency via the LCD module (if necessary). See P34 of the assembly manual.

The 0.2 mm conical tip is small enough. In fact, 0.4 mm is probably small enough. You should have a range of tip sizes from 0.4 - 1.5 mm, depending on the SMD component lead/pad size.
 
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You will need the 3-wire cable for (re)programming the Tx module frequency via the LCD module (if necessary). See P34 of the assembly manual.

The 0.2 mm conical tip is small enough. In fact, 0.4 mm is probably small enough. You should have a range of tip sizes from 0.4 - 1.5 mm, depending on the SMD component lead/pad size.
Your transmitter should have come with a 3-pin cable, unless it's a TRS (which is programmed using the USB-Serial data cable, the same one that you use for updating firmware and testing).

A 0.8mm conical tip is a pretty good fit for most of our kits, you might want to go down to 0.6 or 0.7 depending on how much heat your soldering station can put out and your soldering technique. Personally, I think 0.4 is too small... but Voyager1 might be a lot better at it than I.

Eggtimer Cris
 
Another item that’s generally overlooked in this discussion about soldering is a fume extractor. For those people who might be a little sensitive to these fumes, asthmatics, etc, this might be a good addition to their station. Although lead-free solder is in common use these days, the flux can still produce some irritation. These extractors have charcoal filters that can be replaced periodically.
A cheap way out is to use a small fan and blow the fumes away from yourself. ;)
 
I use the 0.2-0.4 mm tips for 0402 Cs and Rs, and very small pitch ICs. Yes, I agree that the 0.6-0.8 mm is a better choice for 0805 and the ICs in your kits Cris. (Doubt whether I'm better - I've just been doing it with SMDs for nearly 30 years.)
 
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Stupid question #2: I've seen it suggested to use a small conical tip. But what's "small" in this case? The smallest I've found is 0.2mm on Amazon - is that small enough? Or do they come smaller?
Actually I've found a small chisel tip works best as it has more contact area so it heats the pad & component up faster. Maybe 1/16" wide.
 
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