Jump to content

Tego film: Difference between revisions

From Wikipedia, the free encyclopedia
Content deleted Content added
m Development and use for plywood: Fix cite template param names, publishers -> publisher, vol -> volume, using AWB (7701)
Add cat.
(2 intermediate revisions by the same user not shown)
Line 25: Line 25:
== Use for aircraft ==
== Use for aircraft ==
[[File:German Night Fighter Ta 154.jpg|thumb|left|[[Focke-Wulf Ta 154|Focke-Wulf Ta 154 ''Moskito'']]]]
[[File:German Night Fighter Ta 154.jpg|thumb|left|[[Focke-Wulf Ta 154|Focke-Wulf Ta 154 ''Moskito'']]]]
The [[de Havilland Albatross|de Havilland ''Albatross'']] airliner of 1936 had a [[fuselage]] of wooden sandwich construction: wafers of birch [[plywood]] were spaced apart by a [[balsa]] sheet and glued by a [[casein]] adhesive. This same construction achieved fame with its wartime use in the [[de Havilland Mosquito|''Mosquito'']] fast bomber. As well as being a construction of light weight and high performance, it also avoided the use of aluminium, a [[strategic material]] during wartime, and could use the skills of woodworkers, rather than those of specialised aircraft metalworkers.
The [[de Havilland Albatross|de Havilland ''Albatross'']] airliner of 1936 had a [[fuselage]] of wooden sandwich construction: wafers of birch [[plywood]] were spaced apart by a [[balsa]] sheet and glued by a [[Aerolite (adhesive)|Aerolite]] [[casein]] adhesive. This same construction achieved fame with its wartime use in the [[de Havilland Mosquito|''Mosquito'']] fast bomber. As well as being a construction of light weight and high performance, it also avoided the use of aluminium, a [[strategic material]] during wartime, and could use the skills of woodworkers, rather than those of specialised aircraft metalworkers.


When Germany attempted to copy this aircraft as the ''[[Focke-Wulf Ta 154|Moskito]]'', it used Tego film.<ref name="Wood, Hitler's Luftwaffe, Ta154" >{{Cite book
When Germany attempted to copy this aircraft as the ''[[Focke-Wulf Ta 154|Moskito]]'', it used Tego film.<ref name="Wood, Hitler's Luftwaffe, Ta154" >{{Cite book
Line 61: Line 61:
== Modern use ==
== Modern use ==
The term 'Tego film' remains in use around plywood manufacturing today, although it has become generic. It is now used to refer to the phenolic resins still used for the manufacture of exterior plywood, although no longer indicates manufacture in Germany. Most of the plywood produced of this type is now from [[Indonesia]].
The term 'Tego film' remains in use around plywood manufacturing today, although it has become generic. It is now used to refer to the phenolic resins still used for the manufacture of exterior plywood, although no longer indicates manufacture in Germany. Most of the plywood produced of this type is now from [[Indonesia]].

==See also==
* [[Aerolite (adhesive)]]
* [[Redux (adhesive)]]


== References ==
== References ==
{{Reflist|colwidth=30em}}
{{Reflist|colwidth=30em}}


{{DEFAULTSORT:Tego film}}
[[Category:Adhesives]]
[[Category:Woodworking adhesives]]
[[Category:Woodworking adhesives]]
[[Category:Aerospace materials]]
[[Category:Aerospace materials]]

Revision as of 12:53, 19 June 2011

Tego film is an adhesive sheet, used in the manufacture of plywood.

Development and use for plywood

Tego film was developed in Germany around 1930 as a glue for waterproof plywood. It comprised a paper sheet pre-impregnated with a resole phenolic resin.[1] When heated, assembled between wood veneers and then compressed, a strong and waterproof laminated plywood was formed. Most plywood at this time used other adhesives, such as casein. These adhesives were generally applied as aqueous solutions, which caused warping of thin veneers and made it difficult to achieve a solid laminate without risk of voids. As Tego film was used dry, it gave a high integrity result, solid and without risk of hidden weaknesses.[2] This became an important factor in time, when it was applied to use in aircraft construction.

This adhesive was unique at its time and was only available as the Goldschmidt product line from its makers Goldmand AG of Wuppertal. By 1932 it was being exported worldwide.[1]

Use for aircraft

File:German Night Fighter Ta 154.jpg
Focke-Wulf Ta 154 Moskito

The de Havilland Albatross airliner of 1936 had a fuselage of wooden sandwich construction: wafers of birch plywood were spaced apart by a balsa sheet and glued by a Aerolite casein adhesive. This same construction achieved fame with its wartime use in the Mosquito fast bomber. As well as being a construction of light weight and high performance, it also avoided the use of aluminium, a strategic material during wartime, and could use the skills of woodworkers, rather than those of specialised aircraft metalworkers.

When Germany attempted to copy this aircraft as the Moskito, it used Tego film.[3] Flight testing and development of the first Tego film-bonded prototypes from Summer 1943 to 1944 was highly successful. However RAF bombing of Wuppertal in February 1943 (incidentally one of the first Oboe-equipped Pathfinder squadron bombing raids)[4] had already destroyed the only Goldman factory producing Tego film.

For the production aircraft, an ersatz cold adhesive was used, produced by Dynamit AG of Leverkusen.[5] During a test flight on 28 June 1944[3], one of the two aircraft broke up in flight. Investigation showed that the glue left an acidic residue after curing, which in turn damaged the structure of the timber.[3] Mass production of the aircraft never took place after this.

Another case of an aircraft design whose existence was threatened by the acidic replacement adhesive was the largely wood-structure Heinkel He 162 Spatz, the winner of Nazi Germany's last significant aircraft design competition, for a so-called Volksjager "people's fighter" single engine jet-powered fighter-interceptor as part of the Jägernotprogramm in the concluding months of the war.

Modern use

The term 'Tego film' remains in use around plywood manufacturing today, although it has become generic. It is now used to refer to the phenolic resins still used for the manufacture of exterior plywood, although no longer indicates manufacture in Germany. Most of the plywood produced of this type is now from Indonesia.

See also

References

  1. ^ a b Goodman, Sidney H. (1998). Handbook of thermoset plastics. Noyes Publications. p. 47. ISBN 0-8155-1421-2.
  2. ^ Carothers (1947). "XVII. Technical Applications: Wood adhesives". High Polymers. Vol. Volume I. Iinterscience Publishers. p. 244. {{cite book}}: |volume= has extra text (help); Text "W.H." ignored (help)
  3. ^ a b c Wood, Tony; Gunston, Bill (1997) [1977]. "Focke-Wulf Ta154 Moskito". Hitler's Luftwaffe. Salamander. p. 172. ISBN 0-86101-935-0.
  4. ^ Johnson, Brian (1978). The Secret War. BBC. p. 91. ISBN 0-563-17425-0.
  5. ^ Lorenz Bärmann. "TA 154 "Moskito"". Warbirds Resource Group.