From: lew@4ccvw101.scg.hac.com (Lyman Lew)
Newsgroups: rec.models.rc
Subject: Re: Building Tips (was Re: hinges)
Date: 30 Sep 92 19:53:17 GMT
Reply-To: lew@4ccvw101.UUCP (Lyman Lew)
Organization: Hughes Aircraft Co., El Segundo, CA

In article <mhart.717421230@blackjack> mhart@blackjack.dt.navy.mil (Michael Hart) writes:
>
>Went out and bought an UltraSport 60.  Now I have some questions about
>building it.
>
>Straight and square:  I intend to buy a GP wing jig to build the wing.
>This should take care of any warp problems, as far as building goes,
>right?  Any tips/hints/gotchas that I should be aware of while using
>a wing jig?

A wing jig will only minimize the event of a warp. If you use crooked
or twisted wood, the wing can end up warped after removing it from a 
jig.

>Straight and square2: What about the fuse?  Do I need to have a 
>NIST certified flat building surface, or is a reasonably flat one ok?
>By that, I mean no apparant warp to the surface - it's a heavy shelf
>board - when I lay a level across it (all directions) I detect no
>warp to the surface.  I intend to put a piece of ?Celotex? over it
>for pinning.  Comments?

A flat board is adequate. Just draw a datum line on the board and a center
line on all your bulk heads and line them up. Use alignment blocks and
a glue gun for tack gluing the blocks to the board and you'll have a
nice in expensive fuselage jig. Send me line if you have any question
on this technique.

>Hinges: The hinge thread talked a lot about monokote hinges; what about
>those iron-on "gapless" hinges?  Are they just expensive monokote
>like hinges?  Should I use them or the monokote or pin-type hinges,
>or the normal flat hinges supplied in the kit?

Not all of them. Some of the gapless hinges are stitched together. I wouldnt
use Monokote (lace) hinges on power planes because the fuel and oil can 
loosen up the adhesive and you'll loose an airplane that way. Any of the
other commercial hinges are fine.

>Covering in general: I've layed out a color scheme/pattern for my US60.
>It will be somewhat similar to the pattern shown on the ultrasports in
>the advertisements, but much more air-visible colors: White base,
>with red and blue stripings/accents.  So, how is this multi-color
>monokoting done?  Do I cover the whole thing in white then lay the
>colored pieces over the white?  Just cut each piece and put on with
>overlap like a puzzle?
>
You can cover it either way. The former may have problems with bubbles though.

>Covering2: should I apply anything to the wood before covering?
>What about surface finish?  Naturally it needs to be sanded and dusted,
>but what else?

You don't need any wood treatment unless you are using Mica film. Just
make sure the wood is sanded nice and smooth. Make the last grit 320 to 400`
grit. Fill all dings with a good filler and make sure the model is dust-free
before covering.

>
>Glue selection:  Of course, there are glue usage instructions given
>in the assembly manual.  Do the more experienced builders have any
>tips on this?  Are there specific places to use or not to use a 
>particular glue?

CA thin/thick for overall construction. Epoxy for firewall. Carpenter
glue can be used if you don't like CA.

>
>Pushrods: The plans show the pushrods for the elevator & rudder
>exiting the rear of the fuselage on the same side as the connected
>servo; lots of planes have x-crossed pushrods in them.  As far as I
>can tell, this is so the pushrods have a nice, straight travel path.
>The pushrods in the US60 are nearly straight (as shown on the plans)
>but have a slight inward bow to them (i.e. they each bow in, in the 
>middle of their length, towards the center of the plane).  Should 
>I consider modding this, and switching to the crossed pushrod layout?
>
That's a big subject. I've done it both ways and they both work fine.

>Pushrods2: the supplied rods are the metal in plastic tube style; 
>should I consider making my own out of dowel?  Is one type better
>than the other?

They will bothe work fine. The wire and sleeve method should be 
supported in along the bulk heads so it doesn't bow when you
pull up or down on the elevator. 
>
>Proposed Modification: There is no access hatch for the fuel tank.
>I like the idea of being able to get to it.  Would I really be screwing
>up by modding the fuse and putting in a hatch?  Any tips for doing
>this?
>
I wouldn't cut a hole in the fuselage for fuel tank access. Usually
in planes like the US60 you can pull the tank out from the wing
compartment. Just fashion a handle out of duct tape and tape it to
the rear of the tank. This will allow you to pull the tank in and out
through the wing compartment. You can thread the fuel hoses through
the firewall by inserting the fuel lines on a long piece of wire
and guiding it through the holes of the firewall. If you cut a hole
in the fuselage, you will make the front end of the fuselage wimpy.
The engine runs may not be consistent because of increase vibration.
It may also cause foaming of the fuel too. There's nothing worse than
an erratic engine run.

Lyman Lew, lew@caesi.scg.hac.com

>Anything else?  Obviously, I'd like to hear specifics from any other
>UltraSport builders, and tips from any builders!
>
>thanx all!
>
>--
>|   Michael G. Hart                   mhart@blackjack.dt.navy.mil    |







































































From: chrisw@hpscit.sc.hp.com (Chris Wiles)
Date: Mon, 28 Sep 1992 22:10:19 GMT
Subject: Re: Pulse Jet Home Brew
Organization: Hewlett-Packard, Santa Clara, CA