Mechanical joint

The term Spaulders describes the targeted spatial installation of wooden parts. She is one of the carpenters employed, geometric intersection of wood, in the surface and space. In the timber it is a craft technique that is used to determine oblique woodworks.

Is part of the Schiftung Abbunds and is used for example for the production of a roof support structure, in order to ensure a continuous power transmission. An alternative to Spaulders is operated by means of mathematical calculations computational joinery, or the computerized joinery means Abbundsoftware.

• 3.2.1 Example of Flächenschiftung
• 3.2.2 Klauenschiftung in the area 3.2.2.1 Gratklauenschiftung
• 3.2.2.2 Kehlklauenschiftung

Term origin

The word Schiften (English: to shift) comes from the shaft ( OHG scaft = barked branch ) - hence the shifter or Schiftsparren, a special rafters of an inclined section has to connect to a hip rafters, valley rafters or Gratkehlsparren. Another, much more logical explanation is, however, that the word of Schiften imbalance comes. Exactly those woods that are connected to the other construction " wrong " are referred to as Spaulders the umbrella term. See also stems which chamfer produced by an enlarged connection ( bonding ) surface.

Historical development

The Spaulders was althergebracht laced the joinery on the zipper bottom, that is, on the drawing floor a plan of a construction plan ( architectural drawing ) was touched to have the dimensions of the items and their matching available on site production and / or assembly. Hence the term for tearing joinery and finishing the wood. It was put together by chalk or colored cords soaked the profile of a roof at actual size or tied ( tied ).

Today, with the latest software, the so-called Abbundprogrammen ( Abbundsoftware ), even created the most complex design in 3D. It is located in the planned project, move virtually through each room and examine every detail from all sides. Then you can see the data determined by Abbundprogramme, to CNC or joinery, passed. This edit complex wood joints with millimeter precision. The Abbundprogramme have become irreplaceable, whether traditional wooden structures or whole houses, halls, and bridges must be manufactured in timber engineering.

Methods

When Spaulders is basically two methods of profile or Lotschiftung and Flächenschiftung distinguished:

The profile or Lotschiftung

The Lotschiftung, an older term is also Spaulders to factory set (floor plan ) and Lehrgespärre ( rafter profile ), is certainly the oldest method. It is especially to be applied in practice most often. It is based on descriptive geometry and represents only different views into consideration.

In the one the basic view (plan view ) and profile views ( rafter profile ), according to the rules of descriptive geometry positioned so that one relevant points from the profile to the ground and vice versa, can transmit.

Example of Lotschiftung

Now, if a roof is inclined sides, so no vertical gable walls are present, the carpenter is called a roof. If an rafters (rafters are always perpendicular to the horizontal eaves ), in this hip roof, a diagonal embodies a hip rafter is a space diagonal. With the same amount which is overcome, of the hip rafter than spacediagonal a larger standard size, so a different, less tendency. It follows that the hip rafter must be discharged separately, that is, it must be in the profile are shown at actual size. For intersections of the hip rafter with purlin in the plan, which is now explores the Gratprofil, one obtains the horizontal Verstiche which determine the generally oblique claw.

Basic shift

If meeting in a differently angled hipped roof surfaces to each other, you also get different burrs or grooves.

The ridge or valley basic shift is the main purpose to optimally utilize the material. Since the tax base in the structural analysis, the smallest the same (full) cross section originates, therefore, organizations try to bring the Abgratungshöhe a level.

In addition, the scribing and trimming designed by the ridge or valley basic shift easier. Since the Abrgatungshöhe the hip rafters same on both sides, or the Auskehlungstiefe is measured at the valley rafters on both sides of the top edge. In the example picture you see on the left the material requirement, in the middle of the processing without and right with basic shift.

For example, is the determination of the shift, based on a Walmecks with the roof slopes, main roof 45 ° and 51.3 ° hipped roof goes, performed as follows:

Right angles to the ridge line is torn by the intersection of the eaves and bear full Gratsparrenbreite from both sides. Now you versticht through the points newfound, each parallel to the opposite eaves. The points of intersection with the eaves are now seizure ( starting points ) of the shifted Gratsparrenkanten.

The "method", at right angles to Fix end of the ablated Gratsparrenbreite, to the nearest gutter, only works with rectangular building ground and is therefore wrong. Is at right angles House floor a roof inclination equal to 45 °, the Gratgrundwinkel is equal to the roof slope the other side.

Witches section

Since the ridge and valley rafters is inclined less than the rafters or Schiftsparren the main and hipped, he gets called hexene eaves section. Excluded from this are perpendicular and horizontal Traufköpfe. If the main and hip roof rafters provided with a right angle rafter head ( Traufabschnitt ) and transfer these cutting directions on the hip rafters, one speaks of false witches section.

When real witches section you take a cutting direction (eg main roof) and cuts off the other sides of the roof with the same angle with the horizontal. This has the advantage that the angle right end planks extending around the same width and the same inclination. The Witch- section was therefore his name, that the uninitiated the determination had to happen like witchcraft.

Klauenschiftung

The Klauenschiftung can be used both in the Lotschiftung and in the Flächenschiftung to wear.

The Klauenschiftung Schiftungsmethode is applied either when the vertical height of the hip rafter is less than the vertical height of the Schifters or the valley rafters, instead of being chamfered, been lowered. The usual Schiftungsmethode with a boarded back bevel ( Lotschmiege ) should not be applied here. A Schifterklaue determined one by the corresponding edge of a claw- generating component ( the hip rafters, the lower edge and the upper edge of the valley rafters ), verschneidet with upper and lower edge of the component, which is at or below steals ( Schiftsparren ). In traditional joinery by hand, the Klauenschiftung is almost extinct. Even with mechanical prefabrication through joinery systems or joinery is often neglected in the more complex processing.

With exposed wooden constructions these wood connection, however, is highly recommended. In addition, the Klauenschiftung is often also part of master or journeyman's examinations, to provide the craftsmanship of the test specimens to the test.

Kehlklauenschiftung

To a fillet in a claw Kehlschifter ( then Kehlklauenschifter ) to generate verschneidet to the top of the Kehlsparrens with top and bottom edge of the Schifters. The following rule must be observed that there is always to blend to the same height. As in the example of Kehlklauenschiftung (Fig. 1) the height of the eaves. This intersection scales down now runs in parallel with the component which generates the claw. ( Valley rafters )

The back bevel is normally determined by the intersection of the outer edge Schifter with outer edge of valley rafters ( solders ) and perpendicular to the base profile to the profile ripped ( plumbed ). The bevel scale is obtained when the points of intersection outer edge Schifter with flute line ( scale up) and outer edge Schifter with the newly created intersection line ( scale below) takes you to the section and explores the profile. " Scale up" this is blended with top Schifter and scale down with the bottom edge Schifter. By connecting these two points of intersection with the two alloys whose connection forms the Verschneidunglinie between Lot and bevel scales.

Gratklauenschiftung

When Gratklauenschifter it behaves the same, except that instead of the top of the Kehlsparrens the lower edge of Gratsparrens shall prevail.

The Flächenschiftung

The Flächenschiftung is, in contrast to Lotschiftung that much younger method, although this looks back to several centuries. The Flächenschiftung builds on the Lotschiftung, which brings a new dimension to the game. Not only reason and profiles are presented, but also expanded the individual roof surfaces at actual size. This makes it possible to tear woods that are tilted in plan and are distorted.

The scribing lotrechtstehender, oblique woods is not possible with the Flächenschiftung, as these are only in their Abgratung in the area. However, it is necessary to determine the respective edges (for example, from the hip rafter with respect to the upper and lower edge of the rafters), so that the connections can be made to adjacent components. One can thus woods that are placed vertically, not in the area and canted not tear by Lotschiftung. And shall have normal rafters and horizontal changes that are to tear both the Lot and in the Flächenschiftung.

Example of Flächenschiftung

If a roof is covered with tilted rafters in a roof structure, it is necessary to expand it roof surface, so represent at actual size. For this, all the woods Lotschiftung should already be discharged to see " floor plan with profiles as a template from the Lotschiftung " in the picture.

When turning or folding axis, it is advisable to choose the eaves, as this amount is present in all profiles and for the viewer. Logically appear the surfaces to lie on the eaves rather than fold to ridge, fillet, or even ridgelines Among the most important rules when Flächenschiftung one that points always move perpendicular to the axis of rotation between the base and surface, and that all points are constantly on the rotation axis.

To expand the main roof surface from example, one stands a circle in the eaves of the main roof beam profile and suggests a circle from first point to the basic profile. This corresponds exactly to the rotary motion, as if you would put the roof flat on the floor.

This folded First point is now projected in the plan and forms the ridge line area. The first points (seizures ) of the ridge and valley line in the ground, now moving perpendicular to the axis of rotation ( eaves) from the base to the surface, thus creating the first points in the area. If one combines this with the Traufpunkten the ridge and valley line, one obtains the ridge or valley line - area. This means that our unfolded roof surface is determined in its expansion.

To tear the Lotschmiegen, verschneidet one top and bottom edge of the rafter Eaves, with the Lotkante ( Abgratungslinie or outer edge ) of the ridge or valley rafters. The top rafters intersect the Abgratungskante on the eaves. Since points are resistant to the eaves = axis of rotation, Lot starts up parallel ridge or valley line area. To generate Lot bottom, angling for the section where the bottom edge spar to the basic profile ( eave height ) on the roof ( OK rafters) and suggests a circle through this point to the eaves, back to the basic profile. This gives the lower edge of rafter Eaves surface. Now you cut the bottom edge of rafter Eaves with the Lotkante in the ground and this intersection point must fold at right angles to the axis of rotation in the area. Here now starts Lot below parallel ridge or valley line - area.

The claws of the purlins, so the neck with the purlins saddle up, one determined by, cuts the top and bottom edge of rafters with top and front edge of the purlins in the profile. The intersection points on the top edge of the rafter (LO and WO ) is now proposing to the eaves to the basic profile and sweeps them into the floor plan. The intersections on he rafter bottom edge ( LU and WU), one must first angles to the top edge of the rafter, before one turns these around the eaves.

This Verscheidungslinien allow Schiftsparren or exchange to launch in any position to rip and edit. The eaves = XO and XU is Traufabschnitt, wherein XO is at the upper edge portion of the timber and XU portion at the bottom of the timber. LO and WO stand for Lot and scale on the top and LU and WU for Lot and scales on the underside of the rafters. If you connect up with each LO LU and WO WU obtained with sections and claws.

Klauenschiftung in the area

To now in the surface profile ( unfolded roof area ) tear Klauenschifter, you have to extend the elevation at the scale bevels of the claws.

Gratklauenschiftung

This is done by " lower edge of hip rafters at eaves height " with verschneidet " top and bottom edge of rafter Eaves ". The " top rafters Eaves " ( eaves ) meets the bottom edge " hip rafters at eaves height " on the axis of rotation. Since points are resistant to the rotation axis, this is the starting point of " scale up". The " bottom rafter Eaves " meets the " lower edge of hip rafters at eaves height " in the ground and must, as before, the " Lot bottom", can be folded from the bottom to the surface. This is the starting point for " scale down".

Kehlklauenschiftung

When Kehlklauenschiftung in the surface behaves the same as the Gratklauenschiftung, except that instead of the bottom edge of the Gratsparrens, the top of the Kehlsparrens shall prevail.

Witches cut in the Flächenschiftung

The witches cut at oblique rafters is irrelevant in the Flächenschiftung. Only at Kehl planks and tilted valley rafters to host this name is worthy and must be determined similarly extensive as the Lotschiftung.

In an attachment to inventory, Kehl screed is often a sensible alternative to valley rafters, as the rafters of the existing space ( here HD ) does not need to be separated. Here, the screed lays throat tilted to the main roof area and is trimmed on the side roof area. The throat width planks should be adapted to the ( ND) Schiftern. To tear the throat Bohle, one must, similar to the canted rafters show the main roof area.

As an alternative to Hauptdachabklappung, the fillet boards discharge be constructed directly on the Lukarnenprofil ( ND). In this case, must eaves ( TP) - and first point (FP), and emerging and Pfettensenkel be extended laces right. Using a paper strip as a " bar " can now TP and FP, Kervenblei and emerging and Pfettensenkel from the fillet plank in the main roof profile ( HD) lace right on the already constructed in the eaves lace to be removed.

Applications

Who controls the above- stated Spaulders can almost unsubscribe and tie off any roof structure. In preparation for the master's examination is required, among other things.

Kehl corner with unilateral Aufschieblingen

Gratecke with a tilted Mittelpfette

Mandala roof with verschalbaren roof surfaces

Walmeck with increasing eaves

But of course, in practice, the Spaulders is applied.

Entrance roof

Mandala roof with verschalbaren roof surfaces

Literature and sources

• Stade Francis (ed.): The School of Bautechnikers. Course to become self lessons in building construction and related auxiliary sciences. Wooden structures, Moritz Schäfer -Verlag, Leipzig, 1904.
• Association of German Master Carpenters (BDZ ) (ed. ): Training for carpentry craft. Schiften by area method, brother Verlag GmbH, 1998.
• Association of German Master Carpenters (ed.): Schiften by area method. Brother Verlag GmbH
• Association of German Master Carpenters (ed.): Schiften is not rocket science. Brother Verlag GmbH
• Robert Seeger (ed.): Schiftungen, Sweeps, Dachau averages. Brother Verlag GmbH 1931
• Doyen Kress, master school of Tubingen
• The reigning champion training Blumenstein and Volkmann, the Federal Technical School of German craft room Kassel
• Master carpenter Küppers, Master School of the Chamber of Aachen in Simmerath
• Credit Loser PAL (ed.): The new book from the ancient knowledge of Spaulders Blurbverlag