We wanted our bench to be a node to articulate a sequence, so we bended the box.

Plywood furniture fabrication using model ribbing techniques and laser cutting.

Idea and model

We wanted to design a bench that could be able to articulate a system of different benches and get out
from the straight arrangement giving more flexibility, so we curved our element. We had two different
strategies to do this:

We worked in two models following this two strategies and, at the end, we choose the one that we liked the most. This blog entry presents the design following the second strategy and the fabrication process of the design we chose (first strategy). We used Rhino and Grasshopper as modelling and ribbing tools and a laser cutter to fabricate the parts.

Bounding box resulting from revolving the contours forming an angle of approx. 30º.

Modelling the seat and considering to have a floor lamp integrated

Extracting the floor lamp volume from the model with inner shell.

Setting the planes to make transversal cuts determines the ribs separation.

Transversal cutting planes (ribs) from intersection curves.

Ribs in the longitudinal direction. Some pieces had to be cut in order to be assemblable.

Both x and y rib systems together and ready for intersection.

Final result for the design strategy 2 (bending the box).

Fabrication

We choose the model produced following strategy 1. not for the strategy itself but because of the more elegant asymmetrical design and better level of development.

Final result for strategy 1. Cutting edges in diagonal preserving the original bounding box.

Backside of the bench selected for fabrication. Some ribs were divided before fabrication.

Cutting with the big laser cutter at IaaC.

Assembling the numbered pieces.

View 1.

View 2.

View 3.

View 4.

To think about a bench is to think about several people. And several uses. Some people read, others sleep, some sit and some eat. Sometimes it’s just good to be able to do it all. For the IaaCommunity Bench, we decided to keep it simple and keep it working. A table bench. As the section of the bench was predefined to enable the different proposals to connect, we started by defining that the top of the bench would be flat and the bottom would look like… a bench! The editing process begun by creating a cage with the command CageEdit>Select the Bench>BoundingBox> x=15, y=10, z=4. With the Control Points on, we repositioned the points so we could have the form imagined by us. After the form was defined, we needed to close the interior surface using the command Curve> Curve From Objects> Duplicate Edges.  Then to create a surface and finally close the bench, we used the command Loft.

The next step was to use command Contour to create sections of the object in X and Y axis. For that, we created new layers, one for each axe. After creating the “ribs”, we created a new layer called “Intersections”, and used the command “Intersections” to create lines in the intersections between the ribs in X and Y axis. Those lines were used as guidelines to create pipes at the intersections between the ribs.

Using a Grasshopper script we chose ribs on the x-axis, the y-axis and the intersections lines in order to be faster instead of copying and moving each pipe one-by-one manually. After the intersections had been made, we baked the axis individually and grouped each rib by using the TOP view and selecting each line separately.

After we mdke a new layer called DOT, we used the Dot command to name each rib and group it with it’s piece so we would be able to move them around without getting the order of construction lost. We then rotated the ribs so they could be in the same direction. We trimmed each section in order to get the connection edges. Finally we used another script to engrave the numbers and our name in the pieces under a new layer.

To finish the process we deleted the previous layer DOT and drew a rectangle with the dimensions of the wooden board  (1200×2500) under a layer Wood. We manually placed each rib on this plane in order to make the most efficient placement and the less use of materials. Finally we created a layer Cut and renamed all the ribs on that layer. The file was then ready to be exported as a .dxf format.

]]> http://legacy.iaacblog.com/digitalfabrication/2010/11/09/3007/feed/ 0 http://legacy.iaacblog.com/digitalfabrication/2010/11/08/assignment-2-harshad-sutar-julian-hildebrand/ http://legacy.iaacblog.com/digitalfabrication/2010/11/08/assignment-2-harshad-sutar-julian-hildebrand/#comments Mon, 08 Nov 2010 16:59:24 +0000 iaac http://legacy.iaacblog.com/digitalfabrication/?p=2499

This exercise was about designing and fabricating a bench of plywood applying the waffle system and cutting the single elements with a laser cutter:

design process:

contour lines were defined and offsetted by the thickness of the later profiles to loft the inner and outer skin of the bench shape.

inner and outer skin of bench afetr lofting the contour lines

sections were made in x and y direction at varying density to have areas of higher and lower definition in model; finally thes sections were transformed into surfaces.

in order to create the notches to fit the profiles in y direction and those in y direction cylinders had to be generated in the intersecting points to trim the profiles.

trimmed and layouted ( rhino nest) profiles ready to be sent to the laser cutter

mounting process:

cutting of profiles; notches were designed with 2,5 mm while material had athickness of 3 mm; this required additional trimming with a cutter and caused

problems during the assembly as several pieces would not fit correctly.

images of details of the finished waffle model.

perspective views of the entire waffle model.

Team: Mani Khosrovani & Manuel Huerta

The goal of this project was to create a bench that would be part of  a series of benches to be used in a particular space. To do so, we keep the end sections as they are in the original file that was given to us. Our idea was to create a back to back seat, but also make it dynamic where you can sit in different positions and have a smooth surface.

To start modeling the original shape of the bench which is a polysurface you could use CageEdit command - bounding box/world/select cage points you want to work with and then global… when you finally get the modeling done you will have to contour the shape in both directions to make the curves, then you Join each of them in order to have a single curve, next step is offset these curves, after this turn them into PlanarSurfaces, these are the Ribs, after you have the ribs you do the intersections, ProjectToCPlane the ribs and arrange them in an area of the size of your sheet.

The aim of this assignment was to design a bench that would constitute part of a collaborative furniture project and construct a model of 1:2 scale using the waffle structure and a Laser Cut machine. The bench should be designed by transforming a given model in Rhino within a bounding box of 500mm x 500mm x 350mm but keeping the end sections untouched in order to connect with the different benches.

Designing the bench model

As a first step in the design of the bench we exploded the initial model in order to separate the top surface and transform it. In order to do that we rebuilt the surface by putting 10 point counts to both U and V and keeping in mind that this surface is not only going to be the sitting surface of the bench, and therefore it should be comfortable, but also that it should fulfill our aesthetic criteria we activated the control points of the surface and started to move them at will.

We begun by hollowing the arched initial surface so that to create two pits that will consist the main sitting areas (more accurately, one sitting area for two persons), but keeping the back of the bench so that it is more comfortable. Then we moved vertically the control points of the back of the left side of the bench until the borders of the bounding box and we repeated the process horizontally by extruding the right part of the bench until the bounding box and at the same time hollowing the left, so that in one hand it would amplify the waving form and on the other hand it will enlarge the right sitting area and turn it towards the other. Afterwards, with the command Surface, Extrude curve, Along curve, we closed the shape, and by typing Boolean2objects we union the different surfaces. The final result acquired a biomorphic form that serves as a hug, as a nest for the users.

The waffle structure

After completing the form of the bench we started the procedure of the waffle structure system. We used the contour command in both X and Y axis in order to produce sections on the form every 50mm. Then, with the extrude curve command we extruded 50mm the curves of the y axis and due to the fact that the curves on the x axis form loops we used the command offset to offset them also 50mm and we created the surface by typing PlanarSrf.

Afterwards, we selected the ribs from both directions and using Curve Curve from object, Intersection, we intersected them. On each of the intersection curves we created pipes of 2.8mm thickness, we moved them vertically from the end point to the midpoint and then we copied them from the top end to the bottom and putted them in a different layer. Therefore we were able to intersect the different pipes from the according axis of ribs and delete the small part of the intersection by using the split command on each rib and the curve that was created by the intersection. With that procedure we completed the design of the ribs of the waffle structure.

In order to prepare the parts for the Laser cut machine (we used the Epilog Laser cut machine of the Fab Lab Bcn at IaaC) we unrolled each rib, we duplicated their borders and we fitted them in rectangulars of 450mm x 900mm that represent the plywood material of 3mm that we were going to use for the laser cutter.

After cutting each piece we assembled them with the help of the numbers that we engraved on them and we constructed the model of the bench.

The final model