Logo
Builders' Plan Gallery  |  Hip Pocket Web Site  |  Contact Forum Admin  |  Contact Global Moderator
October 15, 2018, 08:24:38 AM *
Welcome, Guest. Please login or register.

Login with email, password and session length
 
Home Help Search Login Register
Pages: [1]   Go Down
Print
Author Topic: Pre-shrinking help please!!!  (Read 920 times)
0 Members and 1 Guest are viewing this topic.
flygilmore
Bronze Member
***

Kudos: 1
Offline Offline

United States United States

Posts: 12

Topic starter


Ignore
« on: May 14, 2018, 11:53:03 AM »

So, I'm fairly new to rubber FF but not to building model planes.  I've spent the last 21yrs. in RC and have over 200 kit/scratch builds under my belt.  So, my issue I'm having is when it comes to small, 1/16" etc. square frame horizontal/vertical stabs on Embryos etc.  I'm the type that I want my Tissue (Esaki) drum tight.  Perhaps that is the wrong attitude to have.  I've had some successes in pre-shrinking the Esaki and then applying it to the tail and some where I still ended up with not really wrinkles, but tissue that wasn't as taught as I'd like.  Does anyone have any suggestions or insight as to how they handle this part of the covering process? I'm still experimenting and I know that it can be done on even the smallest of structures as I've seen it from other builders.  Thanks for any help that you can give!!
Logged
Crabby
Platinum Member
******

Kudos: 125
Offline Offline

United States United States

Posts: 1,857


I never met a modeler I didn't like



Ignore
« Reply #1 on: May 14, 2018, 04:49:26 PM »

The first step is to be sure your structure is light and sound dimensionally. To preshrink esaki make a frame however big you need it. Then make another frame that fits just inside the first one. Now lay the tissue with grain running perfectly North/South, not biased. Gently push frame #2 into #1 with the tissue in place. Now you have a semi taught not drum taught tissue skin. Spray with water liberally and set aside for a few hours or overnight. You will now have a sheet of pre-shrunk tissue. You are never going to satisfied if you think your tissue job isn't perfect, and you may never get out to the field to fly. But you can try to improve with every job. I find that gussets help with those nasty corner wrinkles. Use best practices when covering and learn how to run the grain properly. You won't like this but I never shrink my rudders or stabs, because you can't have any warping back there. Preshrinking does help.
« Last Edit: May 14, 2018, 06:42:43 PM by Crabby » Logged

The Threadkiller!
Crabby
Platinum Member
******

Kudos: 125
Offline Offline

United States United States

Posts: 1,857


I never met a modeler I didn't like



Ignore
« Reply #2 on: May 15, 2018, 09:50:07 AM »

Gilmore, I read my first un-edited reply to you and thought it was awful so I repaired it some, its ready for a re-read. It is possible to get your tissue drum tight, but you have to pay attention to the grain direction or you will get a warp. Rudders and stabs usually don't have enough structure to 'em to support all the tension, and the changing humidities will have their way, Therefore I get mine, (unless its a big plane with good structure in the empanage, then I shrink it right on the stab or rudder) wrinkle-free as possible and leave it. Sometimes I leave the tissue attached to the frame and place the stab "jelly side down" onto the tissue then trim it out. I hope this helps some. I replied because I am generally very happy with my covering.
« Last Edit: May 15, 2018, 10:38:07 AM by Crabby » Logged

The Threadkiller!
Vyper
Bronze Member
***

Kudos: 0
Offline Offline

United States United States

Posts: 17




Ignore
« Reply #3 on: June 07, 2018, 10:21:18 AM »

Just curious Crabby, what material do you build your tissue shrinking frames with?  Also, are the frames rectangular or circular?  I am wondering is a large embroidery hoop would work for that.  My mom gave use about 10 wooden embroidery hoops and I thought I might give one a try to preshrink some tissue.  Thanks!
Logged
flydean1
Gold Member
*****

Kudos: 8
Offline Offline

United States United States

Posts: 659



Ignore
« Reply #4 on: June 07, 2018, 04:00:48 PM »

DIY or Michaels/Hobby Lobby stores sell cheap picture frames in various sizes.  Robust enough for pre-shrinking any tissue.
Logged
Uglykidjoe
Copper Member
**

Kudos: 1
Offline Offline

United States United States

Posts: 4



Ignore
« Reply #5 on: June 15, 2018, 09:15:19 AM »

I had very good results by water shrinking the tissue on the frame as per usual, then applying one coat of dope while still on the frame. Let it cure for a week or so and then cut from frame. Place face down on a glass or similar absolutely flat surface and weight edges to keep it pulled taunt...glue on your stab/fin (I use dope), cut out, rinse, repeat. It looks, in the end, like you shrunk it on the part. Store leftover tissue in a manila folder weighted flat by a phone book.
Logged
dorme
Silver Member
****

Kudos: 6
Offline Offline

United States United States

Posts: 114



Ignore
« Reply #6 on: June 15, 2018, 11:08:45 AM »

You can make the frame for shrinking out of 1/4" foam board (double it if you want).
 What I do is to attach Esaki tissue to the frame with cellophane tape (not making a big deal out of getting every wrinkle removed...you do want to shrink it!). Spray with water-soak it.  Let it dry. 
 Coat the rudder or stab with glue stick and place on the tissue.  THEN cut it out.  Do this for all sides and you will never have a warp or wrinkle.  Be careful with a final coat of dope or Krylon as it can sag enough to attach itself to the opposite side, of which there is no remedy but to replace both sides!
Attached files Thumbnail(s):
Re: Pre-shrinking help please!!!
Logged
dephela
Silver Member
****

Kudos: 2
Online Online

United States United States

Posts: 122




Ignore
« Reply #7 on: June 15, 2018, 11:19:04 AM »

Do you use the covering iron to form and adhere the tissue around the edges of the surface?
Logged

Dennis
dorme
Silver Member
****

Kudos: 6
Offline Offline

United States United States

Posts: 114



Ignore
« Reply #8 on: June 15, 2018, 06:08:26 PM »

I actually wet my finger to roll the tissue over the edges(with water). I rarely use scissors to cut the edges to fit. I should say I don't cut every 1/2" for tabs. Although, I use curved scissors for the finished trim of the edges. I use the trim iron when the glue from the gluestick has dried. It activates it.
If you were to see how I actually attach tissue, you would not only follow my example, you would wonder why you continued to use white glue and dope.  Sorry, if I sound pontificale, but it took years to realize how many try to make an art of this, or don't want to share their secrets and let you struggle with the same old methods they use. It is not that difficult to achieve a good looking tissue job. 
No matter how great the design, the "bones" of the aircraft, when you cover it....that's what people see. 
Logged
Hepcat
Platinum Member
******

Kudos: 275
Offline Offline

United Kingdom United Kingdom

Posts: 1,776



Ignore
« Reply #9 on: June 15, 2018, 09:46:46 PM »

Dorme, don't you want to share your secrets!!
I understand that you attach the tissue to a frame, wet it and let it dry then attach, say, a fin and tailplane by using dope on the framework. When the fin and tail are stuck firmly to the tissue you cut them out.  What is the process if covering a fuselage? Do you cover one side at a time, applying dope to that side, pressing it into the tissue on the frame and then cutting out.  Do you then use a new frame and tissue for each fuselage side? Do you dope the tissue after it is attached to the frame?
Sorry to trouble you but you seem to find it easy but I never find fragile frameworks easy to cover.
John
 
Logged
applehoney
Titanium Member
*******

Kudos: 273
Offline Offline

Canada Canada

Posts: 3,098




Ignore
« Reply #10 on: June 16, 2018, 10:59:40 AM »

An interesting discussion which intrigues me, in that through nearly 75 years if model building I have never pre-shrunk a piece of tissue !   Fascinating.......
Logged
dorme
Silver Member
****

Kudos: 6
Offline Offline

United States United States

Posts: 114



Ignore
« Reply #11 on: June 16, 2018, 11:34:31 AM »

I don't use dope.  I use the gluesticks and it doesn't matter which one.  I use Krylon or rattle can lacquer for finish coats...no more than 3 light coats.
As far as covering the fuse.  I frequently start with a pattern of bond paper to decide what I can cover in one piece for the sides.  Similarly, the same for top and bottom.  I try to cover with a min. of fuss, although, I will light spray some troublesome areas with water and stretch the tissue (don't try this with domestic tissue...only Esaki).
 By the way, I only use white Esaki.  Coloring is either done with chaulk on the inside of the tissue before covering or printing details through the computer.  The program I use is DraftSight.  It's free for 2D which is only what I use.  3D is good only for impressing clients or making sure parts fit. For modeling purposes here, any 2D CAD program is fine or even paint programs like Inkscape (again free). At 72, my new favorite four letter word that begins with "F" is "free"!
As I have learned over the years, for the most part, anything that takes too long or doesn't go together well means you are doing it wrong, fussing too much or don't understand all that you know.
The photo shows the cowl was one piece.  It has a taper from front to back.  The front of the cowl was several pieces.  This is where the trim iron comes in handy smoothing the edges.  Sometimes a little pressure from the shoe of the iron can soften the glue allowing one to push a slight movement. The CAD work was harder in that I had to spent time getting the lines to taper correctly. BTY, the cowl is held on with small magnets, as is the wing.  It's fun to watch it land in pieces and then it all snaps back together.  This really perseveres the plane instead of constant damage.
Attached files Thumbnail(s):
Re: Pre-shrinking help please!!!
Logged
rgroener
Platinum Member
******

Kudos: 27
Offline Offline

Switzerland Switzerland

Posts: 1,197



Ignore
« Reply #12 on: August 23, 2018, 01:41:34 AM »

I am a bit late, but here is the frame I use to pre-shrink my tissue for the stab and rudder structures.
I also have a similar frame big enough for a full Esaki sheet.

As seen in the picture, the tissue is already tight and olive-green chalk was rubbed into the tissue.
Before applying the tissue to the stab, I normally cut the tissue from the frame to reduce tension. In the picture I just laid it on the tissue for size comparison.

From the old tissue on the frame, you can see that I use it quite often Grin

Roman
Attached files Thumbnail(s):
Re: Pre-shrinking help please!!!
Logged
Pages: [1]   Go Up
Print
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Valid XHTML 1.0! Valid CSS!