NEW "Unistrut" Airfoil Rail Guides From SC Precision.

[GaryT]

Here is another very! cool product from SC Precision. Introducing the first true Airfoil Unistrut Rail Guide. First Scott designed and introduced the 1010 Airfoil guides then the 1515 and coming soon is the new Unistrut Airfoil Rail Guide. Made with the same precision as its smaller versions the Unistrut Guide is CNC machined from black Delrin to a true NACA airfoil shape. This allows for easier mounting on the rail and aerodynamics are improved over the round versions. Each set comes complete with two 1/4-20x1" Socket Flat Screws.

ProLine Rocketry has the 1010 & 1515 series airfoil guides in stock now, pricing and availability on the Unistrut version will be announced shortly and will also be available through ProLine Rocketry.

The set pictured below are on my Formula 200 that will be flying at Red Glare on April 12th. Stop by my tent to check out these cool! new Unistrut Airfoil Rail Guides.

 

[powderburner]

Instead of making those buttons even bigger (and uglier), why not make them spring-loaded to retract flush after they separate from the end of the rail? (Dumb idea?)

 

[mpitfield]

Instead of making those buttons even bigger (and uglier), why not make them spring-loaded to retract flush after they separate from the end of the rail? (Dumb idea?)

I would say they are simple and aerodynamic over big and ugly. I think Gary puts a lot of thought into his designs.

 

[GaryT]

Thanks mpitfield but I can't take the credit on the design, these are designed and made by SC Precision. I think powderburner missed the point on why these are shaped this way??

 

[CarVac]

I think they're very cool-looking, personally.

I haven't used rail buttons yet (my rockets have all been light enough for surface-mounted rail guides, or used a tower), but when I do I'm eyeing these. (not the unistrut ones quite yet though)

 

[Titan II]

Already installed. It is a very nice product.

 

[mrichhcirm]

Instead of making those buttons even bigger (and uglier), why not make them spring-loaded to retract flush after they separate from the end of the rail? (Dumb idea?)

Not a dumb idea, just difficult to execute. The mechanism has to work without increasing friction with the rail, and the savings in parasite drag have to be worth the extra weight and complexity of the retract mechanism. And you could fly a lot of rockets with these nifty rail guides in the time it takes to solve those problems. If you really want to eliminate the rail guides in the slipstream, your time is probably better-spent building a tower.

 

[Wingarcher]

Wish someone would do a flow analysis on these things. My bet is that the trailed edge doesn't help as much as we think it might because the top surface is a large flat with an abrupt transtion up to full height and has a square full height drop on the sides. Visually they look better.

A drop off rail guide could be accomplished with a forward lip in the airframe that the rocket sits down on.... the button then secured to the airframe with small sheer pins. Cap the rail channel at the top to snap the guides off and out from under the forward lip. The lip engagement could be designed to do most of the work, it could even extend down the side of the shoe. Shear pins wouldn't hold much load, mostly just would need to resist the rail drag vector to the rear of the rocket as the thing accelerates up the rail.

Or, just stick and motor in it and let it rip. Whatever angle off vertical you wind up with on an average flight probably makes more difference....

N

 

[powderburner]

I think powderburner missed the point on why these are shaped this way??

I have a degree in Aerospace Engineering, and 39 years industry experience in advanced programs. I understood his intended design improvement, just think it is buttocks ugly.

And I agree with mrichhcirm, a tower would be sooo much better.

 

[Binder Design]

Cap the rail channel at the top to snap the guides off and out from under the forward lip.

N

I've done that with those aluminum ACME conformal guides. Bang, gone....

 

[hball55]

Already installed. It is a very nice product.

They look identical to the ones I purchased from Apogee.

 

[hball55]

I've done that with those aluminum ACME conformal guides. Bang, gone....

I have three rockets with those ACME conformal rail guides that haven't yet flown; is this a problem with them? Should I be concerned?

 

[GaryT]

They look identical to the ones I purchased from Apogee.

They are the same ones made by SC Precision.

 

[CarVac]

I have three rockets with those ACME conformal rail guides that haven't yet flown; is this a problem with them? Should I be concerned?

No, he is talking about intentionally knocking them off.

 

[H_Rocket]

I have three rockets with those ACME conformal rail guides that haven't yet flown; is this a problem with them? Should I be concerned?

Nope.. They apparently wanted them to shear free by putting a block at the top of the rail to catch the guides. I am presuming Mike used just enough adhesive to work. The only down side I've found to them is in a high wind situation, if the rocket tries to pivot on the rail, these things can bind up - bad.

 

[Binder Design]

No, he is talking about intentionally knocking them off.

Correct. You can get them out of the rail extrusion after the flight. When the next guy can't figure out why he can't load his rocket with the plate still over the end of the rail.

 

[CarVac]

Correct. You can get them out of the rail extrusion after the flight. When the next guy can't figure out why he can't load his rocket with the plate still over the end of the rail.

Haha haha

This is why we need breech loading launch pads.

Full auto launching!

 

[H_Rocket]

Correct. You can get them out of the rail extrusion after the flight. When the next guy can't figure out why he can't load his rocket with the plate still over the end of the rail.

Mike

How do you attach the guides to provide an adequate balance between holding the airframe securely and being able to shear off without causing any damage?

 

[Binder Design]

Mike

How do you attach the guides to provide an adequate balance between holding the airframe securely and being able to shear off without causing any damage?

I just use the adhesive tape they give with the ACME guides. It sometimes does cause damage to painted surfaces if you just use rattle can paint, It can pull the paint off your rocket in those areas.

 

[CarVac]

I just use the adhesive tape they give with the ACME guides. It sometimes does cause damage to painted surfaces if you just use rattle can paint, It can pull the paint off your rocket in those areas.

I've never had tape come with them. I always just epoxy them on, and if they need to come off my best hope is a heat gun.

 

[Binder Design]

I've never had tape come with them. I always just epoxy them on, and if they need to come off my best hope is a heat gun.

I've got some from a long time ago when they came with adhesive tape. For some reason they don't include that anymore?

 

[SCP]

I have a small batch of the super-size Airfoil Guides for the Black Sky rails. Manufacturing in very limited numbers and don't have dealers carrying them yet, and not yet completely proven out on anything but the Black Sky rail. I know they are standard but some of the cheaper generic rail may have an interference. At the moment I will keep making small batches, so those of you who have been asking for the LDRS projects (or whatever else of course) - here ya go!

email me if interested.........

 

[AlphaHybrids]

I've just always used doorknobs for unistrut buttons.

Edward

 

[fyrwrxz]

I've just always used doorknobs for unistrut buttons.

Edward

LMAO! Just saw KenRico's build for LDRS-looks very similar to Titan II's post in #6. You have to admit they ARE cool-looking! Can't wait for the monster to fly!