Different Epoxy for Different purpose??

Discussions about techniques for rocket building. Leave your tips and tricks to making the perfect rocket.

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OverTheTop
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Re: Different Epoxy for Different purpose??

Postby OverTheTop » Wed Aug 09, 2017 7:27 am

As SMM said, opinions vary. I am leaning towards just buttering up the fin and poking it in these days, and not getting too hung up on fillet size and quality.

In the past I have shaped wooden dowel to sit at the location for the internal fillets on the motor mount tube. They were just glued in place with West Systems. They effectively became the fillets. One side was shaped to conform to the motor mount radius. You just have to figure out how to hold them in place as they dry.

As for internal fillets on the inside of the airframe (under the outside fillets), I have never bothered.
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RainierWolfcastle
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Re: Different Epoxy for Different purpose??

Postby RainierWolfcastle » Wed Aug 09, 2017 10:23 am

- Ben





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Re: Different Epoxy for Different purpose??

Postby drew » Wed Aug 09, 2017 3:00 pm

Andrew Hamilton
AMRS 28 L3
AMRS Records Committee Chairman
Max Alt AGL - 26,850ft - L935 - THUNDA 2019
Max V - 3,004 ft/s, ~Mach 2.67 - L935 - THUNDA 2019

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OverTheTop
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Re: Different Epoxy for Different purpose??

Postby OverTheTop » Wed Aug 09, 2017 3:14 pm

TRA #13430
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"Everybody's simulation model is guilty until proven innocent" (Thomas H. Lawrence 1994)

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Re: Different Epoxy for Different purpose??

Postby RainierWolfcastle » Wed Aug 09, 2017 3:38 pm

- Ben





drew
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Re: Different Epoxy for Different purpose??

Postby drew » Wed Aug 09, 2017 4:14 pm

Andrew Hamilton
AMRS 28 L3
AMRS Records Committee Chairman
Max Alt AGL - 26,850ft - L935 - THUNDA 2019
Max V - 3,004 ft/s, ~Mach 2.67 - L935 - THUNDA 2019

User avatar
OverTheTop
It's only money...
It's only money...
Posts: 2789
Joined: Sat Jul 21, 2007 2:20 pm
Location: Melbourne, Australia

Re: Different Epoxy for Different purpose??

Postby OverTheTop » Wed Aug 09, 2017 5:11 pm

TRA #13430
L3
"Everybody's simulation model is guilty until proven innocent" (Thomas H. Lawrence 1994)

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RainierWolfcastle
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Re: Different Epoxy for Different purpose??

Postby RainierWolfcastle » Wed Aug 09, 2017 5:38 pm

- Ben





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Re: Different Epoxy for Different purpose??

Postby joeman » Wed Aug 09, 2017 10:21 pm

Hi,
Yeah, I guess asking if a glue is stronger or weaker is not always a good question to ask. Depends upon what stresses are upon...and the nature of their application - cyclic, etc.

From what I've read, I guess the choice of glues also comes down to what is practical as well as what the builder is familiar with. I do like the sound of the dowel (as a fillet) trick that OTT mentioned. Thanks.

Anyhow, because of the lack of space I have to deal with, I've ended up bogging up the fin ends (between MM and AF) with 105/206/403. Seemed like it would be a sensible decision because then I know whatever epoxy I ultimately use will be confined to the spot where it is required AND I can use runny epoxy that I know will infiltrate the surfaces being bonded (including the scoring marks I made on the Tang). All I'll need to keep the rocket level. Seems simple.

On another note....
One thing that I've discovered is that I can shine an LED torch through the fibreglass (it is translucent) and I can very easily see how things look. Easier than trying to shine a torch where my head is! Yeah, pretty obvious/simple, but really nice to be able to do.

Cheers

Joe
L1 - Callisto (H133) - 11-Jan-2016
L2 - March Fly (1633K940) - 18-Mar-2018 - RSO

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OverTheTop
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Re: Different Epoxy for Different purpose??

Postby OverTheTop » Thu Aug 10, 2017 7:52 am

TRA #13430
L3
"Everybody's simulation model is guilty until proven innocent" (Thomas H. Lawrence 1994)

drew
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Posts: 1015
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Re: Different Epoxy for Different purpose??

Postby drew » Thu Aug 10, 2017 12:07 pm

Andrew Hamilton
AMRS 28 L3
AMRS Records Committee Chairman
Max Alt AGL - 26,850ft - L935 - THUNDA 2019
Max V - 3,004 ft/s, ~Mach 2.67 - L935 - THUNDA 2019

drew
Southern fried goodness
Southern fried goodness
Posts: 1015
Joined: Sat Aug 01, 2009 10:20 pm
Location: Perth

Re: Different Epoxy for Different purpose??

Postby drew » Thu Aug 10, 2017 12:22 pm

Andrew Hamilton
AMRS 28 L3
AMRS Records Committee Chairman
Max Alt AGL - 26,850ft - L935 - THUNDA 2019
Max V - 3,004 ft/s, ~Mach 2.67 - L935 - THUNDA 2019


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