G-10 or wood for avionics sled

[ericm541]

I've used both mainly from kits that came with a small piece of G10 or plywood to make a sled. With my current project it doesn't come with either and it will be a good size sled. I want to use G10 however, the cheap and impatient part of me wants to just use wood. Appreciate any thoughts pros/cons





Eric M
Nar# 85115

 

[Bat-mite]

You have to consider size of your bay, how thick it can be, how much you want it to weigh, etc. You could also consider a 3D-printed sled.

 

[cavecentral]

If it isn't structural (holding lids together ), I'd say it is a matter of preference.

I like the 3d printed ones.

 

[rms]

If using the standard threaded rod/rods avbay arrangement then it really doesn't matter whether ply or G10 as they aren't carrying any load except for the batteries and electronics and of course the weight of the board itself.
I have used both depending on what I have on hand at the time.

Greg

 

[pondman]

If it isn't structural (holding lids together ), I'd say it is a matter of preference.

I like the 3d printed ones.

+1. I have also machined sleds out of aluminum and they work great.

 

[cwbullet]

Any one have a photo of an aluminum sled?

 

[blackjack2564]

I use what ever is on hand or literally at close reach. Only when space is at a premium will I choose thin G-10 for strength.

For really large sleds, 6- 7.5 -8in etc I go with plywood and a layer of 6oz fiberglass on both sides. Much more economical than G-10.

Any one have a photo of an aluminum sled?

Chuck, don't you have one of Eric's super av-bay sleds? They were all AL, lightened full of holes. Granted there is a small G-10 insert.

 

[ericm541]

Aluminum was my next question lol, I can get it easy and cheaper than G10. The A/V bay is 12" x 5" diameter, what i need is about 4" x 10". would love to see an aluminum sled too, thanks for the feedback.

 

[blackjack2564]

I made one for a 3in rocket many moons ago complete with aluminum battery box that held 2 9volt end to end, with full length cover
. I bent all material on vise and anvil. Even though I had several coats of paint on it, I never slept well worrying about something shorting out & replaced it after several flights.

 

[Worsaer]

Aluminum was my next question lol, I can get it easy and cheaper than G10. The A/V bay is 12" x 5" diameter, what i need is about 4" x 10". would love to see an aluminum sled too, thanks for the feedback.

Don't forget about the need to isolate / insulate components from the mounting plate if it's conductive. I once made an AV bay sled from carbon plate, and shorted out my electronics via the mounting screws.

 

[Worsaer]

Deleted

 

[cwbullet]

I use what ever is on hand or literally at close reach. Only when space is at a premium will I choose thin G-10 for strength.

For really large sleds, 6- 7.5 -8in etc I go with plywood and a layer of 6oz fiberglass on both sides. Much more economical than G-10.




Chuck, don't you have one of Eric's super av-bay sleds? They were all AL, lightened full of holes. Granted there is a small G-10 insert.

I think I might.

 

[pondman]

I've done quite a few aluminum sleds. Pics are from a recent version that is designed to mount two altimeters. Current configuration has a MARSA & a Stratologger. The wiring harnesses are not shown. In flight configuration, the batteries are secured with tie-wraps and electrical tape; never have them come loose. I single 1/4-20 rod runs thru the center of the sled and secures both of the electronics bay end covers and also serves as a mounting point for the recovery harnesses. No issues with this on rockets weighing 80 pounds.

 

[ericm541]

That's cool,there's holes for different electronics too, you machine it yourself?



Eric M
Nar# 85115

 

[RocketFeller]

We made the sled for our rocket out of carbon fiber plate. It was built from scraps and a material sample - I probably wouldn't do it if I was buying the CF.

 

[pondman]

That's cool,there's holes for different electronics too, you machine it yourself?



Eric M
Nar# 85115

No; my design and a local (Cincinnati) machine shop did the work for me. Cost me a couple of lunches and a few bottles of wine!

 

[OverTheTop]

If it isn't structural (holding lids together ), I'd say it is a matter of preference.

+2.

My preference is for G10 just because I usually have it lying around. Wood would be easier for most people to work with. Depends on your workshop tools and capability.

Also, from firsthand experience, it won't go soggy if it sits in a field for 11 months.

 

[soopirV]

I've been toying with the idea of etching my next sled out of double-sided copper clad PCB board. It's FR4 core, which is just a flame-proof version of G10. Rationale is: because it'd be unique and I have the equip to do it, and it would eliminate any need for harnesses; I'd solder the computer to the sled using header pins. Has anyone tried this?

 

[mpitfield]

soopirV I applaud your creativity. I have never heard of this idea but one thing I would be concerned with is a break in the trace due to stress or fatigue. The harness has some inherent slack in it even if it was not in there purposely. Still I would love to see this done just for the uniqueness.

 

[soopirV]

soopirV I applaud your creativity. I have never heard of this idea but one thing I would be concerned with is a break in the trace due to stress or fatigue. The harness has some inherent slack in it even if it was not in there purposely. Still I would love to see this done just for the uniqueness.

Thanks for the encouraging words, and yes, you raise a good point. While I haven't yet designed it, I'm thinking the traces will be quite large (not really optimizing for space here, or for getting around small-pitch components). I'll post some photos once I start! I even have a perfect project for it, my mini DX3 that i want to retrofit for DD experiments.

 

[Titan II]

https://www.rocketryforum.com/showthread.php?53651-L3-Build-Harakiri/page4&highlight=degreaser

The whole thread is worth looking at. Making a board to cluster various components starts around post 109.

 

[soopirV]

https://www.rocketryforum.com/showthread.php?53651-L3-Build-Harakiri/page4&highlight=degreaser

The whole thread is worth looking at. Making a board to cluster various components starts around post 109.

Well, there you go! Good find, will definitely read through. Thanks!

 

[OverTheTop]

Has anyone tried this?

Yep. Did some with magnetic switches built in, terminal blocks for batteries etc. Did them as a sandwich of two boards with some LDPE foam in the middle. A niche was carved out in the foam to house the battery.

Assembling the electronics into the rocket just involved sliding the sled modules down the two allthreads.

I need to find some pics...

 

[soopirV]

Yep. Did some with magnetic switches built in, terminal blocks for batteries etc. Did them as a sandwich of two boards with some LDPE foam in the middle. A niche was carved out in the foam to house the battery.

Assembling the electronics into the rocket just involved sliding the sled modules down the two allthreads.

I need to find some pics...

please do!