4in Nose Cone Ebay

[JBoyson]

NEW DESIGN JUST RELEASED!

This 4in Nose Cone Electronics bay is proven and tested with LOC/PML Nose cones and adds a threaded in electronics bay to any 4in nose cone!
The thread set is designed to be glued into the nose cone allowing for rigid attachment while leaving easy access to electronics with the screw in sled design.

AVALIABLE NOW at Inverted Pursuits Lab

More sizes to come!

 

[jhill9693]

This is a very nice design! Where do you recommend venting for an altimeter?

 

[JBoyson]

I would recommend drilling 2 3/32 holes above the shoulder in the bottom edge of the nose itself.

 

[jhill9693]

I would recommend drilling 2 3/32 holes above the shoulder in the bottom edge of the nose itself.

Wouldn't that cause some aerodynamic weirdness inside the nose cone from the air pressure of the cone moving through the air? Air would spill into the hold, could cause some currents I would imagine. Have you actually done it?

 

[JBoyson]

Have I flown it in that config? No I honestly havent. I typically only place trackers in nose cones not full altimeter setups.

There's a lot of debat (Just did a quick TRF search) on holes in nose cones and what that can do.
I'm of the opinion it has no Aerodynamic effect, but the biggest question seems to be if you vent into the body (Which this design does because of the wire pass through holes for the altimeter to control deploy charges) it could pop the nose cone prematurely. To stop this possibility from hapening you can plug the wire pass through holes with hot glue from the top to keep pressure from passing into the body tube. This also makes them easy to remove later.

I'll argue that drilling a hole just above the sholuder in the nose cone has no effect on performance of the rocket. The nose cone surface should be parallel to the body at that point so it's no serving as like an air scoop at that point. Unlike if you drill in further up, but I've also seen that done too will no noticable ill effect.

Also rememebr to drill the number and size of holes your altimeter reccomends. You can also always dril more smaller holes, just be sure the area of the holes is equal to what the altimeter requested at the end. For Example 2x 3/32 holes could also be ~4x 1/16 holes.

 

[jhill9693]

Thanks, that’s helpful.

 

[jhill9693]

Any chance you could make these available for Estes 3” and BT-80 sizes?

 

[watheyak]

For what it's worth, I've drilled many static ports on the nosecone just above the shoulder with a variety of altimeters. No issues whatsoever.

I think that this issue particular issue is an old wives tale, or a hold over from early electronics with less sophisticated programming.

Also keep in mind that when the barometric sampling really matters is at apogee, when the rocket is at its slowest, and least susceptible to any "aerodynamic weirdness". (Great term by the way)

Cool av-bay product by the way!

 

[tfish]

I've been flying altimeters in the nose cone for a few year's now.
The photo shows my basic setup for STEM stuff I do. I've gone up to Mach 2 without any problems with current electronics. I had a problem with an old G-Wiz..years ago..
I try to put my vent holes low on the nose cones shoulder.


Tony

 

[Zbench]

I think that this issue particular issue is an old wives tale, or a hold over from early electronics with less sophisticated programming.

Truth!!! I got my Level 2 certification in a LOC Goblin with holes drilled around the shoulder of the nose cone with no issues at all. I also have a T -LOC and a 4” Fat Boy all with this same treatment. No issues with any of them. Be not afraid of the nose cone pressure ports

 

[JeffBigg]

I like this design. Have you thought about printing an E-bay that would just be glued into a coupler tube? 4" maybe?

 

[Zbench]

My concern and wonder is can those printed acme threads withstand the pressure of deployment as a heavy nose cone snaps at the end of its shock cord rope?

 

[Hobie1dog]

How is an eyebolt or U-bolt going to mount in the end? The sled is right in the middle, correct?

 

[JBoyson]

I've been using a similar design for years in other rockets I sell with no issue on thread retention when the shock chord reaches it's end. I do typically fly with lots of extra shock cord because I hate the nose cone snapping at the end (unecessary stress imo), but when I've had to do that it's handled everything great. I plan to test fly this all again here in a few weeks and can post an update after.

The eye bolt mounts in a central hole on the bottom of the nose cone and there is a slot in the side you can see in the above pictures where a 1/4-20 nut slides into for retention.

 

[JBoyson]

Hoping to get an answer to the how does it hold up before I can fly it here in a few weeks I did and ejection test on a 3in rocket with 2g of 4F. It held up great for the testing. I'll post more footage after the flight.

 

[Hobie1dog]

I was exploring this design recently and want one to put in a L3 rocket. I think if it didn't have the sled, or the sled offset to one side, then a bigger 1/2" Eyebolt with a 6" long bolt would be perfect to load cylindrical weights onto. Could you make one like that?

 

[JBoyson]

I was exploring this design recently and want one to put in a L3 rocket. I think if it didn't have the sled, or the sled offset to one side, then a bigger 1/2" Eyebolt with a 6" long bolt would be perfect to load cylindrical weights onto. Could you make one like that?

Yes, one like that could be designed. I've been looking at loading weights onto the 4in one in ordet to make my father in-laws rocket stable. What diameter are you looking at for your L3? and would it be a Plastic or Fiberglass nose cone?

 

[Hobie1dog]

Yes, one like that could be designed. I've been looking at loading weights onto the 4in one in order to make my father in-laws rocket stable. What diameter are you looking at for your L3? and would it be a Plastic or Fiberglass nose cone?

4" fiberglass NC

 

[Hobie1dog]

I want to use this style of eyebolt: