AeroTech Open Thread

[SolarYellow]

In my world of auto parts, the only description that can be trusted to properly identify a product is a part number.

 

[MarsLander]

Wilman has them

Thanks, I did see that. I have orders that are outstanding from wildman...I'm holding off ordering anything else until he catches up.

Still need to understand the RDK/CRDK differences in descriptions...so I can manage my delays appropriately.

 

[DabCat]

Can I place a hazmat RCS order for pickup at NSL? When is the deadline to do so if possible?

 

[AeroTech]

Can I place a hazmat RCS order for pickup at NSL? When is the deadline to do so if possible?

You’ll have to call or email customer service.

 

[olivermpb]

I was having a look at my M685 reload and noticed that the nozzle was a single throat instead of a medusa like the drawing on RCS shows. Has there been a change to the reload, or have I gotten the wrong nozzle?

 

[mikec]

I was having a look at my M685 reload and noticed that the nozzle was a single throat instead of a medusa like the drawing on RCS shows. Has there been a change to the reload, or have I gotten the wrong nozzle?

M685s don't use a medusa nozzle any more, no.

 

[pugachu]

M685s don't use a medusa nozzle any more, no.

Sweet, that means I can use the 75mm tapered aft closure with it. the medusa nozzles are too short to use with it.

 

[olivermpb]

M685s don't use a medusa nozzle any more, no.

Maybe? I'm just going off what the Aerotech supplied drawing says.

 

[olivermpb]

Sweet, that means I can use the 75mm tapered aft closure with it. the medusa nozzles are too short to use with it.

Not sure if it's long enough, it's still an extremely short nozzle. It's just that it's a single throat.

 

[mikec]

Maybe? I'm just going off what the Aerotech supplied drawing says.

The drawing is out of date. The last M685 I flew, last year, had a single throat nozzle and I wouldn't say it was particularly short, maybe post a pic?

 

[StreuB1]

Sweet, that means I can use the 75mm tapered aft closure with it. the medusa nozzles are too short to use with it.

M685 does indeed now use the single throat nozzle.

M685 single throat nozzle is submerged within the tail cone closure by 0.225" (see my drawing below)

Note: Drawings/models are produced by me from my own hardware and for my own personal use, for my own design projects. They are not available, please do not ask.

 

[AeroTech]

TRA L3 #1 and AeroTech/RCS VP Karl Baumann with a partial inventory of our larger high-power motor casings.
View attachment 1715949696002.jpeg

 

[dr-ws]

TRA L3 #1 and AeroTech/RCS VP Karl Baumann with a partial inventory of our larger high-power motor casings.
View attachment 645710

Say, could I get seven of these, and five of those, please, and maybe four of those over there? And, before I forget, add six of those guys right behind them over there?
"Partial inventory"? There IS hope for us after all! (Mr. Baumann is smiling for a reason!) Thank you for the "drool over" photo!

 

[NTP2]

Thank you for the "drool over" photo!

they know our weakness

 

[tfish]

The drawing is out of date. The last M685 I flew, last year, had a single throat nozzle and I wouldn't say it was particularly short, maybe post a pic?

They do make 2 different 75mm single throat nozzles now.



Tony

 

[Theory]

They do make 2 different 75mm single throat nozzles now.

View attachment 645754

Tony

yes

 

[pugachu]

TRA L3 #1 and AeroTech/RCS VP Karl Baumann with a partial inventory of our larger high-power motor casings.
View attachment 645710

Save one of the 75/10240 casings for me!

 

[olivermpb]

Following up on the M685 nozzle change thing, I've noticed that Thrust Curve and Aerotech list different total impulses for the motor. Is this difference due to the nozzle change? Aerotech says it makes 7,741 Ns, while Thrust Curve has it at 7,561 Ns.

 

[Christian D Michael]

Where do you source the wires used in the leads for the First Fire igniters? I need igniters that can fit in a .064" throat and making them out of that wire has the best result. I'm 90% certain it's 27-28 gauge two conductor solid core wire. I can't find that, only stranded two conductor wire, or single conductor solid core. Working with leftover First Fire wire has been far less tedious to make igniters out of than leftover Twiggy wire.

 

[AeroTech]

Following up on the M685 nozzle change thing, I've noticed that Thrust Curve and Aerotech list different total impulses for the motor. Is this difference due to the nozzle change? Aerotech says it makes 7,741 Ns, while Thrust Curve has it at 7,561 Ns.

Not sure, it could be the difference between what we measure on our stand vs. TMT numbers.

 

[AeroTech]

Where do you source the wires used in the leads for the First Fire igniters? I need igniters that can fit in a .064" throat and making them out of that wire has the best result. I'm 90% certain it's 27-28 gauge two conductor solid core wire. I can't find that, only stranded two conductor wire, or single conductor solid core. Working with leftover First Fire wire has been far less tedious to make igniters out of than leftover Twiggy wire.

We don't actually source the wire but we purchase the completed wire assemblies from a vendor.

 

[2-0turbo]

Following up on the M685 nozzle change thing, I've noticed that Thrust Curve and Aerotech list different total impulses for the motor. Is this difference due to the nozzle change? Aerotech says it makes 7,741 Ns, while Thrust Curve has it at 7,561 Ns.

Just to keep things in perspective, you're talking about a 2% difference in total impulse. It could be from a variety of sources (nozzle, air temp, air density, mixing speed, etc.) but it should have negligible impacts on simulated or actual flight results.