Arcas HV build thread

What do you mean by allign the nuts properly?

The nuts used to attach the eyebolt need to have their "flats" running parallel to edge of the CR. If, not they will bind when you insert the MMT into the frame. The eyebolt must also be parallel. I think they have a picture in the instructions. I'm sure someone can chime in or provide a photo. Believe me, they will fit.

Ok, ill take your word for it.

Hey guys,

Managed to get the shock cord through the hole, but should the end of the shock cord touch the aft centering ring? Or is it ok like this:

littlemisterbig said:

Hey guys,

Managed to get the shock cord through the hole, but should the end of the shock cord touch the aft centering ring? Or is it ok like this:

View attachment 188123

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your fine like that. also you can buy a nomex protector for the chock cord and you won't need to replace the cord for a long time.

I would highly recommend having some sort of protection over that shock cord such as a Kevlar sleeve. That Nylon can melt. Also (people will have different opinions here) but if you have a forward closure failure and have flames coming out of both sides of the motor, this shock cord is done. Get the protector!!!! It can be installed after the rocket is complete but it may be difficult.

Alex, do you have one i could borrow?

littlemisterbig said:

Alex, do you have one i could borrow?

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they're only 13$. Its not real something you can "borrow".

https://www.apogeerockets.com/Building_Supplies/Parachutes_Recovery_Equipment/Shock_Cord_Protectors

Ill just use duct tape

Why'd you give up on eyebolt?

Sorry i havent done an update in a while. Finally got to it tonight and managed to get the shock cord epoxied to the mmt. Not much else to report.



Thanks, littlemisterbig

littlemisterbig said:

Sorry i havent done an update in a while. Finally got to it tonight and managed to get the shock cord epoxied to the mmt. Not much else to report.

View attachment 188349

Thanks, littlemisterbig

Click to expand...

That shock cord isn't going anywhere!

rocketgeek101 said:

Knock 'em off and start over. Better to do the work to make it right... especially since this is a HPR rocket.

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It'll be fine. It's not like the tubes are polished stock, as long as his fin roots are secured well to the motor tube and the external fillets are good he'll have no problems.



Braden

Got the forward section epoxied (with the exception of the nc). Planning on epoxying the mmt in the airframe later today. Will probably do the fins tomorrow.





Thanks, littlemisterbig

you need to sand things before you bond them. Read the sticky I wrote.

I did sand them

Got mmt epoxied in, it wasnt too bad, however it was a pain in the but to epoxy around the retainer. Next time ill do the retainer last.





Thanks, littlemisterbig

Looks good. A handy tip to make it easier next time is to wrap the retainer in tape so even if you get epoxy on it it doesn't matter as its on the tape.

Thanks, cant believe that didnt occur to me.

Just saying, it would have been better if your aft CR was right at the edge of the fin slot so it gets glued to that also.

Dang ok, will it be ok as it is?

littlemisterbig said:

Dang ok, will it be ok as it is?

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Yeah it will. It's just now all the stress from the motor will be on the glue joints, where ideally you'd want the stress to go from the Aero Pack > rear CR > fin tabs > airframe with the epoxy only holding the pieces together.


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Ok. I got the first fin tacked on this morning, the rest will follow this afternoon.

Got three fins tacked on

First set of fillets, I dont think they're horrible but i dont think they are that great.





Thanks, Littlemisterbig

Here's a little tip before you do anymore fillets - mask the fins and air frame. Less clean up. They look good though!

Ok, i didnt have any normal masking tape, ill borrow some from school tomorrow.

Second set of fillets these were done with tape.

A lot less mess!

Yeah, and a lot prettier