3D Printing Has anyone designed some 3D printable 29mm fly-away rail guides?

[rocketgeek101]

Before I try to do this myself, I'm wondering if someone has already designed some 3D printable 29mm fly away rail guides they could share the CAD file for with me? I have found files for ones as small as 38mm diameter airframes, but nothing smaller. Thanks!

 

[swatkat]

Also interested

 

[rharshberger]

Shouldn't be to hard to use Cura or similar to rescale , though it may require open up screw holes and pivot rods later.

 

[Mike_Andrews]

I made the larger fly away guides that are on Thingiverse. They had an issue with drag on the rail that lead to a flight "not going to plan".

I have been poking at a revision that uses needle bearings for rollers on the sides of the rail. Swamped at the moment, but I am working on getting the design finished.

I'm using Fusion 360 and will release the CAD and STL files once I'm done.

I really want to see what improvements there are with a clean airframe vs. the weight of the flyaway guides.

 

[cwbullet]

Thingiverse: https://www.thingiverse.com/thing:3706482

 

[rharshberger]

Thingiverse: https://www.thingiverse.com/thing:3706482

I have printed a 38mm set of these,cthe difficulty is finding the proper size metric rods. I used carbon arrow shafts and designed bushings to make them the right size to fit the plastic parts.

 

[cwbullet]

If someone sends me arrow shaft diameters, I can ask my son to adjust the size.

 

[0011001100]

If someone sends me arrow shaft diameters, I can ask my son to adjust the size.

7.16mm measured with metric Brown & Sharpe micrometer. That is for "Standard" sized arrows like what you would find at walmart or bass pro shops ect. There are other sizes but they are mostly found in dedicated archery shops only.

 

[rocketgeek101]

If someone sends me arrow shaft diameters, I can ask my son to adjust the size.

I have some 2.54mm diameter rods from an old kite I was thinking of using.

I made the larger fly away guides that are on Thingiverse. They had an issue with drag on the rail that lead to a flight "not going to plan".

I have been poking at a revision that uses needle bearings for rollers on the sides of the rail. Swamped at the moment, but I am working on getting the design finished.

I'm using Fusion 360 and will release the CAD and STL files once I'm done.

I really want to see what improvements there are with a clean airframe vs. the weight of the flyaway guides.

Are you referring to the ones cwbullet linked? Those are the ones I had come across on my own earlier. Do you foresee an issue with just taking the existing files and scaling them down to the diameter I need?

 

[Yukon@K-9 Rocket Tech]

I needed one anyway so maybe I'll design and upload to Thingiverse

 

[swatkat]

I needed one anyway so maybe I'll design and upload to Thingiverse

just no doggo logos.

 

[BDB]

As an alternative, you could also look in to a 3D printed launch tower. I have printed this one, just waiting on a green light to give it a shot.

https://www.thingiverse.com/thing:2538353

 

[rocketgeek101]

I've spent the evening designing a set of 29mm guides from scratch. Not quite done, but this is what I have so far:

When sizing the inner diameter for the guides, is it best to make it the same as the OD of the airframe or make them a tad oversized?

I'm hoping to print them out tomorrow. Should take about 4 hours total (1 hour per part) at 100% infill.

 

[Yukon@K-9 Rocket Tech]

just no doggo logos.

Hehe already have Cat Lover freinds and told em will post raw F360 files so anyone can stick as many cat logos as they want. But sorry comes with doggo logos stock STL

 

[0011001100]

When sizing the inner diameter for the guides, is it best to make it the same as the OD of the airframe or make them a tad oversized?

Make them over and then use something like masking tape to take up the difference.

 

[swatkat]

Hehe already have Cat Lover freinds and told em will post raw F360 files so anyone can stick as many cat logos as they want. But sorry comes with doggo logos stock STL

But why ruin art with graffiti?

 

[rocketgeek101]

Alright, here is my first attempt at making my own 29mm guides. The design is inspired by the fly-away guides that Additive Aerospace offers (thought the smallest ones they make are 38mm). Overall I am pretty pleased with how they turned out. I'm a bit concerned that the springs I used are a bit too strong; providing too much tension on the rail and causing the guides to bind. Unfortunately, I don't have a rail with me to check. I used 2.5 mm diameter fibreglass rods from an old kite in the construction.

 

[Mike_Andrews]

Yes, drag on the rail was a significant factor in my launch going sideways. :-/

This is the basis of the guides I've been poking at. https://www.thingiverse.com/thing:3706482

But if you can use maybe some teflon on the friction surfaces that would improve things. I'm thinking strips of the tape you can buy.
I have to find time to get my rails done.... With the current restrictions on what is allowed at my launch site I'm probably going to skip any more launches until the fall. So hopefully I can spend some time on these.

 

[cwbullet]

Guys pick one diameter of a Carbon Fiber rod and I will start on the design.

 

[rharshberger]

Guys pick one diameter of a Carbon Fiber rod and I will start on the design.

The best thing to pick is probably a commonly available rc plane carbon tube as arrow shafts vary one manufacturer to the next, rc plane carbon tubes are easy to find online and have a listed I.D and O.D.

Something like this: https://www.hobbytown.com/midwest-carbon-fiber-tube-.210-od-x-.132-id-x-40-mid5822/p28815
Its from an easy and somewhat reliable source, Hobbytowns website has at least 10 different diameters if the posted one is too large.