Yeah, there is a bit of a whet out problem with it, but if you dip your
finger in a bit of isopropyl alcohol and run your finger along it, it helps
lubricate and slightly softens the putty without affecting the cure, so you
can get okay-looking fillets just doing that. You can then sand it down
fairly easily. I've also used EWF to add easily sandable material on top
of this stuff, allowing you to shape it down to a nice aesthetic fillet
without expending a ton of effort to sand the epoxy clay. I like to try
new techniques with each rocket's fillets, though, and I think my next one
will be using the John Coker method, using a pretty heavily
thickened/filled long cure, like West System, then use a plastic spoon to
remove the excess and shape it. I would like to try your method, though,
too, just letting gravity do its thing. My only concern is getting it
evenly distributed between fin and airframe, especially on 3-fin models --
I like the rotisserie idea.
On Tue, Jun 7, 2016 at 11:46 AM, Kenneth Brown <ken@xxxxxxxxxxxxx> wrote:
The problem with putty is that it doesn't whet out to the body and fin
since it's so viscous. I prefer to use a 60min epoxy (longer set times
generally mean a stronger bonding epoxy) filled with microspheres to
thicken it slightly and then put the body on a rotisserie horizontally to
keep the epoxy from sagging. I get very nice fin root fillets this way. I
should add that I will pin the fins in place with a couple of spots of
super glue to hold the fins in place while the epoxy cures.
Ken
On Jun 7, 2016, at 11:38 AM, Alexander Jones wrote:
Adrian, it looks like you can get this stuff at some home depot stores,apparently in the plumbing section. On another note, I've had okay results
with the loc-tite brand stuff that's also available off the shelf at HD (I
tend to go for the stuff that's wet applicable, which might explain my
success with it re: the brittle issue), but it really depends how much
stress you're planning to put on the joint. If it's minimum diameter or
you're otherwise expecting super-high accelerations and mach+ speeds, I'd
reevaluate it....if you're staying below mach and you're using a robust fin
attachment like TTW, you should be fine. Also, all the putties are
actually A+B, just some of them combine it into one "log" of putty, with
the hardener in the outside layer, usually the colored layer, then the
epoxy is the core and is usually white or at least lighter-colored....you
use a plastic knife or something to chop off a little section of the log
and just knead it together until it's homogeneous.
adrian@xxxxxxxxxxxxxxx> wrote:
On Tue, Jun 7, 2016 at 11:02 AM, Adrian P. Bailey <
Thanks Alexander and Mike!years) so they may not have it in stock for same day. They do have A+B
I can’t get the Amazon order to work (and have been using Prime for
epoxy putty.
brittle and the fillets break off.
It’s for fin fillets and what I’ve read is that some putty is too
roc-chat-bounce@xxxxxxxxxxxxx] On Behalf Of Alexander Jones
From: roc-chat-bounce@xxxxxxxxxxxxx [mailto:
Sent: Tuesday, June 7, 2016 9:44 AMguy gives a brief review of this exact product:
To: roc-chat@xxxxxxxxxxxxx
Subject: [roc-chat] Re: Epoxy putty
Adrian, looks like you're in luck, there's a rocketry forum post where a
http://www.rocketryforum.com/showthread.php?74822-Rectorseal-EP-400-Epoxy-Putty-Works-Great
!
wrote:
On Tue, Jun 7, 2016 at 9:41 AM, Adrian P. Bailey <adrian@xxxxxxxxxxxxxxx>
recommendations? I’m looking for something that Amazon can deliver today… ;)
Has anyone used Rectorseal Ep-400 Epoxy Putty, or have other
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