One Manufacturer to provide total solution from prototyping to low volume production including all customized parts, standard parts and final assembly of a new design customized functional unique chair:
Standard Position Rotated Position
Project Statements:
Job Name: Saddle Chair/Stool
The Saddle chair is a unique tool with saddle like seat covered with leather, and a unique shape of backrest with leather covered also. The back rest is also capable of rotating independently against the seat though the redesigned mechanism, this chair is designed to help people to site properly and reduce the back pain. This product is target to very high end market.
Total 53 parts and 27 is new designed components and total 11 different manufacturing process and 8 supplier get involved to complete the project:
l Customized mechanism processes: CNC Milling, CNC Turning, EDM sparking, wire Cutting, laser cutting, welding, bending, polishing, leaser engraving and assembly.
l Seats processes: Blow molding, cooper inserts, memory foam manufacturing, leather cutting and stitching, Gel pad molding, upholstery and assembly.
l Backrest processes: Laser cutting, welding, expand foam molding, leather cutting and stitching, upholstery and assembly
l Standard components: PU/Nylon wheels, reinforced gas springs, NSK bearings, screws and washers.
l Material used: Stainless steel 304, Cow leather, expanding PU foam, memory foam, Polypropylene, cooper and Aluminum.
l Lead time: 50 weeks
l Quantity: 26 core chairs and 36 core stools.
Project Background:
Max prototype specializes in providing the total solution for complex project at small volume production since we have strong capability to provide varies manufacturing services and design service at much lower cost compares in western countries.
David Frances, the human chiropractor and the owner of www.chairedlogic.com from Australia devoted himself to develop the saddle chair and stool to help consumers to resolve the issue of the poor sitting posture 4 years ago, thus to reduce the recurring back pain.
About the company of Chaired Logic:
David France B.Ed.B.Sc.Grad.Dip.M.Chiro
Having gained a Masters Degree in Chiropractic, 15 years experience as a human chiropractor and having taught Ergonomics at Macquarie University (Sydney) David France is an authority on the science surrounding workplace ergonomics. Seeing the obvious link between sitting for long periods and back problems David became passionate about improving how we sit.
David developed the Core chair to directly attend to the frustrations of patients with recurring back pain and poor posture.
Milestone 1 (Redesign the unique chair, lead time 5.5 weeks)
A) Customized rotatable mechanism redesign:
The chair needs the backrest to be capable of rotating independently against the seat, also should combine the standard function of the gas spring smoothly move up and down. The mechanism intends to be designed, unique, strong, easy assembly and lower cost compared with first design.
l Redesigned the shape from rectangle to round to looks more uniform design
l Proposed the material with stainless 304 to achieve high end designed finish with strong and stable function.
l Cancelled the full set of bearing sleeves, nuts and rings to totally improve the consistency of function and make it much simple to assembly.
l redesigned the bearing assembly way to achieve more reliable function
l Changed the tube material to SS304, size and manufacturing method to achieve high quality
l Redesigned the mechanism assembly way to make it much easier to assemble for end consumers.
B) Redesign of Saddle Like Seat
The seat designed to need higher end cosmetic and very comfortable feeling at reasonable price:
l Redesigned the seat top and seat bottom contour and dimension to get most comfortable feel by end users
l Redesigned the method to produce the seat from injection molding process to blow molding to save cost without sacrifice the quality
l Redesigned the fabric layer to leather layer to improve the cosmetic quality
l Redesigned the foam from standard foam to combination of standard foam, memory foam and gel pad to improve the comfort of sitting
C) Redesign of Unique Backrest
The back rest expects perfect position against the seat, better looking, better feeling and easy assembly at reasonable cost.
l Redesigned the inner supporting structure of backrest from weak plastic to stainless steel metal tubes to save cost and be more stable
l Redesigned the covered foam from standard material to expanding molding foam with higher shore A hardness to improve the level of comfort
l Redesigned the fabric top layer to leather layer to get higher quality
l Redesigned the way to assemble the back rest and also improve the consistency of assembly
Milestone 2 (Making Prototypes to access the new design and production capability, lead time 11 weeks)
Search and puchase the high end standard PU wheels, new and special aluminum base and reinforced gas springs, high duty bearing and stainless steel screws, nuts and washers.
A) Produce the unique mechanism sample (14 customized stainless steel components)
l CNC milled and turned top housing with SS303 for gas lifting purpose and backrest rotating purpose, the house then welded on the laser cut stainless 304 plates which used to support the seat.
CNC Milling and Turning of Stainless Steel 304 with brush finish
l CNC milling, turning and EDM sparking stainless steel of bottom housing to hold the bearing and CNC turning the inner/invisible gas spring holder, Press to fit the bearing into bottom house with punch machine and fixture
CNC Milling, Turning and EDM Sparking Stainless Steel with brush finish
l CNC turning, laser cutting both stainless steel gas lifter levers and rotating handles and relevant components, then screwed and welding all together
Laser cutting, CNC Turning, Bending and Welding of Stainless Steel 304 with brush finish
l Weld top housing and bottom housing together though the invisible gas spring holder
l Stainless steel tube was formed to the required section shape and bended with rubber core to final shape, then laser etched the logo and hand polish to brush finish
Bending, laser etching and wire cutting the stainless steel tube
l Weld the tube into bottom house and hand polish the whole mechanism to be with brush finish
B) Produce the Seat sample (3 customized components plus leather upholstery)
l Make the blow molding parts from PP material with 4.0mm thickness, also designed the though holes on the part to improve the strength.
l Press the designed and copper inserts to base holes on the part. This new design of cooper insert is to avoid the spin issue compared the traditional way which insert co-mold into blow mold.
l Glued gel pad, standard foam, memory foam on the seat cover and assembled the leather on the seat cover
l Use stainless screws and washers to assemble seat cover and seat bottom.
C) Produce the backrest sample (11 customized parts plus leather upholstery).
l Make the stainless steel 304 frame base on shape of back rest. Laser cutting all tubes and then welded together on the fixtures.
l Put the metal frame into expanding foam tooling which is made from aluminum
l Assemble the leather on the surface of expanding foam
l Screwed the bottom stainless plate on the bottom of backrest
Milestone 3 (2 Plastic Blow molds, Steel bending tooling, welding and machining fixtures, low volume production, lead time 34 weeks)
l Make further design improvement based on prototype quality
l Create final spec, part list and delivery schedule.
l Communicate and coordinate technique, quality issue and delivery schedule with all suppliers