Quantcast

Custom (overengineered) Eggtimer Tx sled and Receiver enclosure

The Rocketry Forum

Help Support The Rocketry Forum:

hotwings

Well-Known Member
TRF Supporter
Joined
Nov 18, 2020
Messages
53
Reaction score
88
Location
Melbourne, FL
Have been working on building several Eggtimer kits. I bought into the Eggtimer ecosystem with a TRS Tracker, Proton, WiFi Switch, and LCD Receiver.
I've done surface mount before, but a component as delicate as the GPS unit was certainly a new skill. Cris was fantastic to work with, and walked me through a solder bridge I got _under_ the module.
I plan to purchase more Eggfinder kits in the future, and will be building out a full collection of several of these. You really can't beat the feature set you get with a few hundred bucks of electronics from Eggtimer.

I'm going for my L1 this weekend, and am flying a MAC Performance 4" Blackfly, with a Nosecone avbay. I'm not using any computer controlled charges for this flight, just motor charge. But I wanted a tracker, and to get some experience flying electronics and measuring flight data, before the outcome of the flight depends on their operation. I also have a JLCR on the parachute.

Decided to spend the time to draw up a custom sled and handheld enclosure for the system. The sled perfectly fits inside a MAC Performance 54mm Nosecone avbay, and seats an M6 Nut on the bottom. The nut slips in easily, and then the sled can be hand threaded into the bottom end cap of the avbay. I printed 3 or 4 revisions of the avbay, to trial and error the best dimensions for a quick battery change that also can be rock solid secure with a single cable tie. Cut the cable tie, rotate battery ~10 deg away from the sled, and it slides right out. With it cable tie in, there is zero movement, and the bottom of the battery tray is printed solid with 10 layers.
The electronics are mounted with brass heat inserts that match the hole patterns to the boards.
The receiver has a locking toggle switch, so it isn't accidentally switched off after the Tx and Rx are synced. The receiver handle screws off in one and a half rotations for easy access to a 2.2Ah LiPo battery in the handle.

IMG_20201215_000239.jpg
IMG_20201215_000244.jpg

IMG_20201215_000252.jpg
IMG_20201215_000307.jpg


If anyone would like the STL files, DM me! Maybe someone else could find these useful.
Note that these are not easy prints though - they involve very tall and thin supports, and some steep overhangs without supports. I printed them on a heavily modified Raise3D N2. But, if someone wants to try it on another printer, I'm happy to help and would love to see how it works out.

AVBay ScreenShot.JPG
AVBay ScreenShot 2.JPG
 
Last edited:

cerving

Owner, Eggtimer Rocketry
TRF Sponsor
TRF Supporter
Joined
Feb 3, 2012
Messages
4,154
Reaction score
1,420
The long antenna on the tracker is the one that we sell for the receiver... for the transmitter, we recommend the Linx ANT-916-CW-QW, it's about the same length as the wire antenna but it has much better specs. We have a few on hand... by popular request.
 

Conway Stevens

Tacos For 10
TRF Supporter
Joined
Aug 17, 2020
Messages
188
Reaction score
107
Location
Wellington, Co
The long antenna on the tracker is the one that we sell for the receiver... for the transmitter, we recommend the Linx ANT-916-CW-QW, it's about the same length as the wire antenna but it has much better specs. We have a few on hand... by popular request.

I was curious as the one I got from you Cris is the Linx. Just hadn't seen anyone put the bigger antenna on the transmitter. Wasn't sure if it would even gain anything.
 

hotwings

Well-Known Member
TRF Supporter
Joined
Nov 18, 2020
Messages
53
Reaction score
88
Location
Melbourne, FL
I was curious as the one I got from you Cris is the Linx. Just hadn't seen anyone put the bigger antenna on the transmitter. Wasn't sure if it would even gain anything.
Yeah, I'm not sure either. I found the half-wave antenna for $7. Every rocket I will fly this in has ample room, figured I would try it.
So far, I've measured ~1.2 miles on the ground, with the Tx laying in my driveway inside a nose cone, through palm trees and a few blocks of houses, and the Rx kept signal.
 

Tobor

Get your peanuts....
TRF Supporter
Joined
Oct 8, 2016
Messages
1,949
Reaction score
570
Have been working on building several Eggtimer kits. I bought into the Eggtimer ecosystem with a TRS Tracker, Proton, WiFi Switch, and LCD Receiver.
I've done surface mount before, but a component as delicate as the GPS unit was certainly a new skill. Cris was fantastic to work with, and walked me through a solder bridge I got _under_ the module.
I plan to purchase more Eggfinder kits in the future, and will be building out a full collection of several of these. You really can't beat the feature set you get with a few hundred bucks of electronics from Eggtimer.

I'm going for my L1 this weekend, and am flying a MAC Performance 4" Blackfly, with a Nosecone avbay. I'm not using any computer controlled charges for this flight, just motor charge. But I wanted a tracker, and to get some experience flying electronics and measuring flight data, before the outcome of the flight depends on their operation. I also have a JLCR on the parachute.

Decided to spend the time to draw up a custom sled and handheld enclosure for the system. The sled perfectly fits inside a MAC Performance 54mm Nosecone avbay, and seats an M6 Nut on the bottom. The nut slips in easily, and then the sled can be hand threaded into the bottom end cap of the avbay. I printed 3 or 4 revisions of the avbay, to trial and error the best dimensions for a quick battery change that also can be rock solid secure with a single cable tie. Cut the cable tie, rotate battery ~10 deg away from the sled, and it slides right out. With it cable tie in, there is zero movement, and the bottom of the battery tray is printed solid with 10 layers.
The electronics are mounted with brass heat inserts that match the hole patterns to the boards.
The receiver has a locking toggle switch, so it isn't accidentally switched off after the Tx and Rx are synced. The receiver handle screws off in one and a half rotations for easy access to a 2.2Ah LiPo battery in the handle.

View attachment 442435 View attachment 442436
View attachment 442437 View attachment 442438

If anyone would like the STL files, DM me! Maybe someone else could find these useful.
Note that these are not easy prints though - they involve very tall and thin supports, and some steep overhangs without supports. I printed them on a heavily modified Raise3D N2. But, if someone wants to try it on another printer, I'm happy to help and would love to see how it works out.

View attachment 442439 View attachment 442442
Your design of the sled & handheld are really sharp!

If you ever do another revision of the sled, I would suggest adding some form of strain relief to the base of the antenna. A high-G lateral load on that big antenna will shear the RP-SMA connector off the circuit board.
 

Banzai88

Lvl 1,Wallet....Destroyed
TRF Supporter
Joined
Jul 15, 2015
Messages
2,561
Reaction score
726
Your design of the sled & handheld are really sharp!

If you ever do another revision of the sled, I would suggest adding some form of strain relief to the base of the antenna. A high-G lateral load on that big antenna will shear the RP-SMA connector off the circuit board.
I can attest to that first hand, even with the small antenna!
 

hotwings

Well-Known Member
TRF Supporter
Joined
Nov 18, 2020
Messages
53
Reaction score
88
Location
Melbourne, FL
I can attest to that first hand, even with the small antenna!
Good to know! I've got a design in my head for a solution to this. Won't take me more than a few hours to draw it up, print it, and install it on this sled. I'll just go ahead and do that before the first flight!
 

jbr

Well-Known Member
Joined
Nov 22, 2017
Messages
449
Reaction score
204
why not add these to thingiverse?
 

jbrracer

Well-Known Member
Joined
Aug 11, 2020
Messages
362
Reaction score
152
Location
Indiana
You aren’t alone brother! Engineering and design are half the fun and a whole lot cheaper than motors!
 

Attachments

hotwings

Well-Known Member
TRF Supporter
Joined
Nov 18, 2020
Messages
53
Reaction score
88
Location
Melbourne, FL
You aren’t alone brother! Engineering and design are half the fun and a whole lot cheaper than motors!
Beautiful! Amazing to see so many builders drawing up parts and printing. Would be curious if anyone has analyzed tensile, impact, etc strength for different filament. I've never done any experiments for my robot structural parts, but have mostly printed with MatterHackers PRO Tough PLA.

...Rocketry has certainly changed since I last flew ~15 years ago.
 

jbrracer

Well-Known Member
Joined
Aug 11, 2020
Messages
362
Reaction score
152
Location
Indiana
Beautiful! Amazing to see so many builders drawing up parts and printing. Would be curious if anyone has analyzed tensile, impact, etc strength for different filament. I've never done any experiments for my robot structural parts, but have mostly printed with MatterHackers PRO Tough PLA.

...Rocketry has certainly changed since I last flew ~15 years ago.
Cnc kitchen on YouTube has done it all. Like crazy crazy amounts of testing on filament types, print Orientation, shell thickness, infil amount, print temps, and more. Ive done all my stuff in pla and pla + no issues yet knock on wood
 

hotwings

Well-Known Member
TRF Supporter
Joined
Nov 18, 2020
Messages
53
Reaction score
88
Location
Melbourne, FL
Cnc kitchen on YouTube has done it all. Like crazy crazy amounts of testing on filament types, print Orientation, shell thickness, infil amount, print temps, and more. Ive done all my stuff in pla and pla + no issues yet knock on wood
Nice!

That has been my experience with structural parts for robots. I don't intend to print anything other than mounting hardware for electronics, cameras, etc. And things that stay here on terra firma under 1G.

But, wow, is 3D printing convenient for AvBays. Excited to get to L2 build next. I'm doing a HED 6" Blackfly.
 

jbrracer

Well-Known Member
Joined
Aug 11, 2020
Messages
362
Reaction score
152
Location
Indiana
Nice!

That has been my experience with structural parts for robots. I don't intend to print anything other than mounting hardware for electronics, cameras, etc. And things that stay here on terra firma under 1G.

But, wow, is 3D printing convenient for AvBays. Excited to get to L2 build next. I'm doing a HED 6" Blackfly.
Right on brother, give me pm if u need help
 

Tobor

Get your peanuts....
TRF Supporter
Joined
Oct 8, 2016
Messages
1,949
Reaction score
570
You aren’t alone brother! Engineering and design are half the fun and a whole lot cheaper than motors!
I know it's just a bulkplate, but for some reason I really dig that Neon Yellow(?) with the ring of socket head cap screws. I guess it reminds me of the custom mods seen on R/C gas cars.
 

jbrracer

Well-Known Member
Joined
Aug 11, 2020
Messages
362
Reaction score
152
Location
Indiana
I know it's just a bulkplate, but for some reason I really dig that Neon Yellow(?) with the ring of socket head cap screws. I guess it reminds me of the custom mods seen on R/C gas cars.
its more than a bulk plate = )
 

jbr

Well-Known Member
Joined
Nov 22, 2017
Messages
449
Reaction score
204
Nice!

That has been my experience with structural parts for robots. I don't intend to print anything other than mounting hardware for electronics, cameras, etc. And things that stay here on terra firma under 1G.

But, wow, is 3D printing convenient for AvBays. Excited to get to L2 build next. I'm doing a HED 6" Blackfly.
6 inch blackfly is fun, M1550

1611175531885.png
 

Nick Hutton

Well-Known Member
Joined
May 9, 2019
Messages
75
Reaction score
51
Location
QLD, Australia
Hotwings very kindly sent me the stl’s. Over the last couple of days I’ve printed the Eggfinder receiver in PLA and the TRS/Wifi sled in PETG - with full supports on a Prusa MK3+ using pretty PETG settings. Both came out well. I’m just waiting on some inserts I ordered on eBay so I can mount stuff up. Thanks so much for sharing the files. I am a long way off achieving this sort of design ability with Fusion 360.3E2ECA1F-17F4-4735-866B-DE21A419BEC6.jpeg63F241EF-6D8B-4008-995F-FE5A5620D3A1.jpeg
 
Top