Logo
Builders' Plan Gallery  |  Hip Pocket Web Site  |  Contact Forum Admin  |  Contact Global Moderator
December 16, 2019, 07:32:48 AM *
Welcome, Guest. Please login or register.
Did you miss your activation email?

Login with email, password and session length
 
Home Help Search Login Register
Pages: [1]   Go Down
Print
Author Topic: What techniques for stripping old tissue?  (Read 680 times)
0 Members and 1 Guest are viewing this topic.
Gnu
Bronze Member
***

Kudos: 1
Offline Offline

United States United States

Posts: 45


Topic starter
Balsa Bender



Ignore
« on: January 01, 2012, 08:48:46 PM »

I have a couple of older (around 20 years) but great flying models, a coupe and a P-30, that need recovering. The Jap tissue, Esaki I believe, has become so brittle that it splits with even the most careful handling. I've been away from modeling for a few years and the models have been sitting in the garage.

What is the best way to remove the old stuff? Cut away the open areas and just work on the material left attached to wood, or attack the panel as a whole? Cover the panel with some sort of absorbent material and apply thinner or MEK or acetone? Most of my models are lost or destroyed before they come to this. Suggestions?
Logged

All your lift are belong to us, make your time.
RonT
Silver Member
****

Kudos: 2
Offline Offline

United States United States

Posts: 200


Support our cottage industry mfrs. & suppliers




Ignore
« Reply #1 on: January 01, 2012, 09:20:08 PM »

Hello Gnu!
Welcome to the HPA forum.
Before addressing the tissue removal issue, it is necessary to know how it was attached (dope?) and what type of glue was used for construction.
Ron
Logged

Ron T
AMA, NFFS
McCook Field - FAC
Cloudbusters
gossie
Platinum Member
******

Kudos: 49
Offline Offline

Australia Australia

Posts: 1,733



Ignore
« Reply #2 on: January 01, 2012, 10:19:45 PM »

If models built with PVA, and dope used to attach the tissue, get a big plastic bag, pour 1/2 cup of thinners or acetone into it, drop the wing etc. in, tie the bag off and leave it for about an hour and the tissue should just about drop off.

If balsa cement used for construction, do NOT follow the above.   Will be a job for elbow grease/grit paper.
Logged
Gnu
Bronze Member
***

Kudos: 1
Offline Offline

United States United States

Posts: 45


Topic starter
Balsa Bender



Ignore
« Reply #3 on: January 01, 2012, 10:50:57 PM »

Nitrate dope was used to attach the covering. I believe I used CYA for all of the construction. For sure not Duco and such.


Logged

All your lift are belong to us, make your time.
p40qmilj
Platinum Member
******

Kudos: 29
Offline Offline

Canada Canada

Posts: 1,863


love that P40Q



Ignore
« Reply #4 on: January 02, 2012, 08:03:48 AM »

 Grin  Gnu   I would apply elbow grease to all surfaces Roll Eyes
That's why God invented sandpaper (100 or 150grit) depending on the wood size.

JIM Grin
Logged
RonT
Silver Member
****

Kudos: 2
Offline Offline

United States United States

Posts: 200


Support our cottage industry mfrs. & suppliers




Ignore
« Reply #5 on: January 02, 2012, 08:54:32 AM »

Gnu - This has worked well for me in the past.
Put the structure in a large trash bag.
Wet a rag with acetone or MEK. You want damp, not soaking wet.
Place in bag and seal bag.
Come back in a couple of hours. Bt this time, the fumes should have softened the dope.
Slowly peel off the tissue.
Repeat as necessary.
Good  luck.  Smiley
Ron
Logged

Ron T
AMA, NFFS
McCook Field - FAC
Cloudbusters
sweepettelee
Platinum Member
******

Kudos: 19
Offline Offline

United States United States

Posts: 1,311


Simplicate & add more lightness. Keep sanding!



Ignore
« Reply #6 on: January 02, 2012, 01:49:09 PM »

Similarly to RonT's method, I have wrapped & taped paper towels entirely over covered surfaces to be exhumed.
Then I put the wing, stab, whatever into plastic bag with acetone or MEK.  See that the towels are saturated
by the solvent by turning bag about before going away to let the stuff do its work.
I don't trust waiting as long Ron states.
I only wait about 20 minutes. If the solvent and fumes have not fully penetrated to the adhered structures
by then, often even some CA and alaphatics will soften and allow bits to come loose if left for 2 hrs.
I had a wing that was 30 yrs old and nothing I did would get the doped-on Esaki off!
Except sanding [after cut&peel activity] for two or three days of sweat-equity. :-)
Logged

Leeper
RonT
Silver Member
****

Kudos: 2
Offline Offline

United States United States

Posts: 200


Support our cottage industry mfrs. & suppliers




Ignore
« Reply #7 on: January 02, 2012, 06:20:49 PM »

Sweep....
If I should ever again have a model long enough that it might need to be recovered, I will try your method.
By then I could be in my 90's and two hours could be a lifetime! Grin
Ron
Logged

Ron T
AMA, NFFS
McCook Field - FAC
Cloudbusters
Gnu
Bronze Member
***

Kudos: 1
Offline Offline

United States United States

Posts: 45


Topic starter
Balsa Bender



Ignore
« Reply #8 on: January 02, 2012, 06:35:13 PM »

Thank-you gentlemen. I will probably try laquer thinner and follow up with a can of elbow grease.

Happy Gnu year, guys.
Logged

All your lift are belong to us, make your time.
Dimeflyer
Platinum Member
******

Kudos: 55
Offline Offline

United States United States

Posts: 1,349



Ignore
« Reply #9 on: January 03, 2012, 07:29:16 PM »

The elbo grees and sand paper is the only way to go if your lumber is still strong enough to stay intact while you work !!
that will not only remove the tishue but resmoth the surfsce as well !!
George
Logged
sgblake
Bronze Member
***

Kudos: 0
Offline Offline

Canada Canada

Posts: 10



Ignore
« Reply #10 on: January 25, 2012, 12:41:13 PM »

Greetings all:
I've tried to remove the tissue from the wings on my Banshee OT power model by putting the wings in a large sealed garbage bag with a dish of lacquer thinner. The wings are covered with Peck domestic tissue which was stuck on with Sig nitrate dope about 25 years ago. I had no luck at all. No matter how long I left the wings in the bag with lacquer thinner, the tissue/dope didn't soften up at all. So, it looks like it's sandpaper, or build new wings...

Thermals!
Simon
Logged
RonT
Silver Member
****

Kudos: 2
Offline Offline

United States United States

Posts: 200


Support our cottage industry mfrs. & suppliers




Ignore
« Reply #11 on: January 25, 2012, 02:17:22 PM »

Hi Simon,
I'm not sure how well laquer thinners work as a solvent for dope but, I have had success with MEK or acetone, using the sealed bag method.
Thermals,
Ron
Logged

Ron T
AMA, NFFS
McCook Field - FAC
Cloudbusters
Gnu
Bronze Member
***

Kudos: 1
Offline Offline

United States United States

Posts: 45


Topic starter
Balsa Bender



Ignore
« Reply #12 on: February 02, 2012, 06:05:23 PM »

Believe me, the part about sealing the model in a trash bag (and setting it out on the curb) has ocured to me!
Logged

All your lift are belong to us, make your time.
gstew
Copper Member
**

Kudos: 0
Offline Offline

United States United States

Posts: 7



Ignore
« Reply #13 on: November 29, 2019, 08:01:46 PM »

Update on tissue stripping....

I had 3 wings to strip, a new starter F1B from Starlink-Flitetech (stripping because they had some warps that would be difficult to remove) and a pair of old coupe wings from the early 90's (kit-bashed from the old Blue Ridge Models Coupe DeVille kit).

Using the technique of 'wrapping the panel with a paper towels and covering that with Saran Wrap, then pulling back the Saran Wrap, saturating the paper towel with laquer thinner, re-wrap, then wait a few minutes', the F1B wing covering (Russian tissue, apparently a wood-fiber product that does not un-warp with heat, but tough!) came off nicely in almost panel-sized pieces.

The old coupes were a bit more challenging. The thin, likely Esaki tissue (who remember what they used to cover a wing almost 30 years ago?) laid down with good home-built aircraft nitrate did not come loose as easily AND mostly in strips or small chunks. I was left with a lot of remaining tissue crumbs, especially around the dihedral/polyhedral joints and tips.

That's where the 'pour some thinner into a plastic bag and put the surface in' technique rescued me. The bags the F1B wings came in were a near perfect fit for about 3/4 of each full coupe wing. I carefully snugged on a bag, poured in a bit of thinner, sloshed it around, then withdrew the wing a couple of bays at a time and scraped off the tissue with my fingernails. That worked well without damaging the wing. I only had to dip each half twice to get 98% off.

I used an automotive laquer thinner with plenty of tolene. BAD stuff! But it softens the dope well.

I AM happy that even back then my standard construction technique is to use thin CA for the assembly, then fillet the joints with thinned aliphatic resin wood glue. For dihedral break reinforcement I CA a thin layer of CF tow over the top and bottom of the LE, TE, and main spars. Very light, very strong, and not obtrusive into the airflow. BUT during the tissue removal, I noticed some of the ends of the tows loosening, so I am glad I used 2 glues with different solvent bases.

Now to go find some good tissue for the coupe wings in my covering boxes and start re-covering. The F1B wings (along with 2 others I got un-covered) will get 1/2mil mylar on the bottoms and probably Litespan or something similar (low-shrink, it is not a CF D-Bix, but CF tube spar with no capstrips and a balsa TE) on the tops.

Greg in Mississippi

P.S. I don't like that to do this with any success, I need to use at least one bare hand in the strong thinner, mostly to use a nail with a very light touch so I don't gouge the structure. I'd rather do this fully gloved, but that is not to be.
Logged
Crabby
Titanium Member
*******

Kudos: 134
Offline Offline

United States United States

Posts: 2,193


I never met a modeler I didn't like



Ignore
« Reply #14 on: November 29, 2019, 11:10:19 PM »

Grin  Gnu   I would apply elbow grease to all surfaces Roll Eyes
That's why God invented sandpaper (100 or 150grit) depending on the wood size.

JIM Grin

Guys I am on board with Jim on this. I have taken a whole fuselage after I hand-stripped most of the big stuff, and gave it a nights soak in my wife's hot tub, then with a stiff toothbrush worked off all the remaining stuff, but all that lacquer and MEK, and so on is gonna bite your butts one day. There is no safe substitute for good old elbow grease, a few beers and some soft piccolo music on the hi-fi.
Logged

The Threadkiller!
tom arnold
Gold Member
*****

Kudos: 30
Offline Offline

United States United States

Posts: 695


Casper Wyoming



Ignore
« Reply #15 on: November 30, 2019, 10:27:15 AM »

I find myself recovering regularly and it is one of main reasons I attach my tissue with diluted white glue and build with CA. When it comes time to recover, I poke holes in all the wing bays and between fuselage stringers. Then I fill the tub with warm, soapy water and sink the victim and hold it under water with weights of some sort. I actually feel like some kind of domestic murderer throughout this process. Leaving it overnight, the tissue them just falls off in sheets. Contrary to popular belief, the frame does not, repeat: does not warp when it dries. The frame IS delicate while wet, but will dry in any position it is pinned to (such as pinning washout in the wings---the fuselage is unaffected).

It is really very easy.
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!