Drat! I glued myself into a corner!

[Huxter]

I used a 3d printed jig w my Antar, have 2 of the 3 fins glued on... THEN realized I could not get the jig off!





The 2nd fin is only tacked on, but I chose to cut the jig tabs off. Lesson learned!

 

[Huxter]

I'll haveta say this is the softest balsa I have ever worked with. The long 'dorsal' fin was quite bent - had to use tape to hold it done while gluing.

 

[hermanjc]

Been there myself

 

[Scott_650]

I'll haveta say this is the softest balsa I have ever worked with. The long 'dorsal' fin was quite bent - had to use tape to hold it done while gluing.

Not surprised considering the worldwide balsa shortage - we’ll probably see more less than optimal balsa for quite some time…I pretty much paper all my balsa fins, the increased strength and decrease in sanding is worth the slight weight penalty to me. I haven’t even opened my ANTAR box yet - yours’ is looking good.

 

[Huxter]

I wonder if the softer balsa equates to younger balsa - baby balsa? I REALLY need to learn to paper my fins - it seems like a win/win/win situation...

Can't think of many mods to do w this one - gonna keep it pretty stock. Got a new can of Rustoleum Hunter Green for the stock paint job.

 

[messedupryan]

Rustoleum Hunter Green

Given your launch location, are you planning on ever seeing this thing again?

 

[kuririn]

THEN realized I could not get the jig off!

Been there, done that.
Trying not to glue fins on when I'm sleepy now.

 

[John_lennon]

@kuririn where'd you get those nifty fin jigs

Dyl

 

[neil_w]

@kuririn where'd you get those nifty fin jigs

http://qualmanrocketry.com/

 

[John_lennon]

http://qualmanrocketry.com/

Thanks Neil, so many little companies out there doing all kinds of stuff that you'd never know about. Unless you've got first-hand knowledge of them or have been told about them. A lot of stuff doesn't come up in Google queries.

 

[neil_w]

Thanks Neil, so many little companies out there doing all kinds of stuff that you'd never know about. Unless you've got first-hand knowledge of them or have been told about them. A lot of stuff doesn't come up in Google queries.

That is true, particularly so with Qualman because he's not active on the forums these days. Any time someone posts a picture with those fin jigs in it there are a flurry of inquiries about who makes them.

 

[KenECoyote]

Just snip one of those outermost ends and it should come off...then epoxy back or just leave it as is? If you have some cutter with a razor blade edge (I have one made by Craftsman), it should make a good clean cut and can be glued back easily I think.

 

[Huxter]

Qualman baffles are excellent too - my favorite

 

[Ronz Rocketz]

Not surprised considering the worldwide balsa shortage - we’ll probably see more less than optimal balsa for quite some time…I pretty much paper all my balsa fins, the increased strength and decrease in sanding is worth the slight weight penalty to me. I haven’t even opened my ANTAR box yet - yours’ is looking good.

I think Randy Boadway on the Rocketry Show said he's expecting more 3D printed fins as balsa becomes more scarce over time. Most likely true...

I call the Antar the Masking Tape Simulator 2021. I didn't bother and switched the sides of the main fins.

The Qualman fin alignment guides are great, and I'm addicted to the baffles. I inserted one into the Super Mars Snooper which I'm hoping wasn't a mistake. We'll see. I'm ready to paint the ridiculous NC. Wish me luck...

 

[boomtube-mk2]

It could be worse Huxter:

 

[Huxter]

I inserted one into the Super Mars Snooper which I'm hoping wasn't a mistake. We'll see. I'm ready to paint the ridiculous NC. Wish me luck...

Good luck! Would love to see the finished work!

What makes you worry about the baffle in the Snooper - more weight? CP/CG?

 

[Bat-mite]

Might be a good idea to coat the jig in Vaseline before you use it next time. I do that with my rail button screw mounts. I want them epoxied to the inside of the tube, and pulled tight against the tube. So I use the screw to pull it tight. But if I epoxy over the screw, then the screw will never come out. So I coat the screw in Vaseline before screwing it in. After full cure, I good twist breaks it loose and it screws right out.

 

[Ronz Rocketz]

Good luck! Would love to see the finished work!

What makes you worry about the baffle in the Snooper - more weight? CP/CG?

It's not a long body tube. The rocket has a long stuffer tube so the baffle is close to the opening. The baffle leaves about 5 inches for laundry so should be fine.

 

[Huxter]

I think I'll try a 3d printed baffle in my Snooper. The baffle is 1.5 inches long and weighs ~ 13 grams. According to my Yu-Gi-Oh ruler, this is where it would go to give me 5 inches of laundry room - pretty close to the engine tube ~ an inch?

Is this about where you put your baffle? I wonder what the Qualman baffle weighs? I do not have any extra to weigh. I may have to print some lighter baffles (PETG).

 

[Ronz Rocketz]

I think I'll try a 3d printed baffle in my Snooper. The baffle is 1.5 inches long and weighs ~ 13 grams. According to my Yu-Gi-Oh ruler, this is where it would go to give me 5 inches of laundry room - pretty close to the engine tube ~ an inch?

Is this about where you put your baffle? I wonder what the Qualman baffle weighs? I do not have any extra to weigh. I may have to print some lighter baffles (PETG).

View attachment 485977

I have it about here. I estimate there’s a half inch between the tube and baffle which is 2.5” long. This give 4.5” space for laundry. I built a new baffle and weighs 8g.

 

[Huxter]

Thank you for weighing a new baffle!

Do ya think it would it hurt to do this? I'd have ~ 6" of laundry room! Just seems like over pressurizing that .5 to 1 inch main tube unnecessarily - no?



I'll probably use the engine tube to push this baffle in w some epoxy.

 

[Ronz Rocketz]

Thank you for weighing a new baffle!

Do ya think it would it hurt to do this? I'd have ~ 6" of laundry room! Just seems like over pressurizing that .5 to 1 inch main tube unnecessarily - no?

View attachment 486006

I'll probably use the engine tube to push this baffle in w some epoxy.

View attachment 486007

Hard to say. Don't want the back pressure out the rear of the motor instead of pushing the NC. I figure it needs some space between the tube end and baffle. How have the baffles held up before?

 

[BigMacDaddy]

Great thing about 3D printing -- cut the jig off and make another... probably $.50 or so in filament...

 

[Huxter]

How have the baffles held up before?

I only have 1 3d printed baffle in my Mars Longship, and that's yet to be launched

Great thing about 3D printing -- cut the jig off and make another... probably $.50 or so in filament...

I love my 3d printer! I bet it cost less than .05 cents!

 

[bad_idea]

Might be a good idea to coat the jig in Vaseline before you use it next time. I do that with my rail button screw mounts. I want them epoxied to the inside of the tube, and pulled tight against the tube. So I use the screw to pull it tight. But if I epoxy over the screw, then the screw will never come out. So I coat the screw in Vaseline before screwing it in. After full cure, I good twist breaks it loose and it screws right out.

I do this too. As a novice BAR, it is always nice validation to see an experienced rocketeer using the same method as something I've come up with on my own.

 

[Ronz Rocketz]

The SMS went surprisingly high on the D12-5. Woulda been fine on a C11-3. I realized I had no room for the altimeter so cut into the NC shoulder and enforced with epoxy putty. Hopefully it’ll work.

 

[Bat-mite]

I do this too. As a novice BAR, it is always nice validation to see an experienced rocketeer using the same method as something I've come up with on my own.

Thanks. The risk, of course, is getting the Vaseline on something that you want to stick!

 

[AfterBurners]

I don't recall ever being in that situation. Glad it worked out for you.