Origami chair redesign: a fiberglass exterior

Hey, thanks for checking out my blog!  Last week I promised to write about creating the exterior of my chair.  Below, I describe my thought process around editing the seat shape, choosing a color and an exterior finish.  I also discuss the mistakes I made and how I corrected them.

Between layers of fiberglass and resin I sanded from 80-150-220 grit—a mistake.  Because resin will drip, I was limited to applying it only to surfaces that were level.  I then had to reposition the chair and again apply resin only to the level surfaces.  All of the sanding and limits to resin application meant that it took several weeks just to apply one layer of resin to the entire chair.
Between layers of fiberglass and resin I sanded from 80-150-220 grit—a mistake. Because resin will drip, I was limited to applying it only to surfaces that were level. I then had to reposition the chair and again apply resin only to the level surfaces. All of the sanding and limits to resin application meant that it took several weeks just to apply one layer of resin to the entire chair.

First, I needed to ensure that the ergonomic seat I had just carved from spray foam and covered in body filler would be comfortable for any adult.  Minne-faire was approaching, so I decided to display my unfinished chair in order to collect some data about the comfort level of the seat and whether or not I needed to edit the shape.  My carving mistake was quickly revealed:  every woman who tried the seat loved it and every man found the back half of the center ridge too high!  Oops!  Luckily, that was an easy fix.

Second, I considered the color.  I could not decide between bright orange and white so when I invited visitors to try out the seat, I also asked them to vote for a color.  Their choice was clear:  classic bright red!

Throughout the dried, but not yet sanded, layers of resin (the shiny areas in this photo) appeared dozens of small mars and dents—with every single layer.  This was one clue that resin alone was going to be insufficient coverage.
Throughout the dried, but not yet sanded, layers of resin (the shiny areas in this photo) appeared dozens of small mars and dents—with every single layer. This was one clue that resin alone was going to be insufficient coverage.

Third, for a sleek, contemporary look I decided to give the chair a fiberglass finish.  Most of the chair received one layer of fiberglass and 4-5 layers of resin.  The seat and back were coated with 3 layers of fiberglass cloth and 5 layers of resin.  Between each layer I sanded the resin from 80-150-220 grit which turned out to be a mistake.  Each non-final layer of resin should only be sanded to 80 grit so that the next layer will easily adhere.

The extra sanding did help by yielding a perfectly smooth surface before applying the next layer of resin.  However, despite the smooth application surface, each new layer of resin consistently produced substantial mars & dents.  I seemed unable to pour a smooth layer of resin which made me wonder if I was ever going to be happy with the finish.

The white circles in this photo surround dark spots on the seat and back.  Those are not shadows but, rather, the dark green body filler that I used when I ran out of pink body filler.  It is showing through 3 layers of fiberglass cloth and resin.  This was my second clue that fiberglass and resin were going to be insufficient coverage.
The white circles in this photo surround dark spots on the seat and back. Those are not shadows but, rather, the dark green body filler that I used when I ran out of pink body filler. It is showing through 3 layers of fiberglass cloth and resin. This was my second clue that fiberglass and resin were going to be insufficient coverage.

I thought that using fiberglass resin would negate the need to paint the chair because the resin can be tinted with universal pigments (the kind that your local paint store uses).  The hardware store where I bought the resin threw in the pigment for free and I combined them in a plastic bucket.  The resin color looked perfect in the bucket!  But once on the chair I realized that resin is super translucent because it contains no opaque base.  Therefore, the 2 different colors of body filler I used on the seat were very visible, even through 3 layers of fiberglass cloth and resin!

If I ever do this again, I will make sure that the color of my chair before laminating is consistent throughout. With an even-colored base, the tinted resin and fiberglass cloth would have been adequate coverage.  Still, to get a smooth surface I would have to spray the resin rather than pour or brush it on.

The difficulty in achieving a smooth surface combined with the translucency of the resin made me realize that I must paint the chair.  After pricing High Volume Low Pressure (HVLP) paint spray guns ($180), primer spray guns ($50), paint ($100), and the rest of the equipment I would need to do the job myself, I decided to save some money and have my chair painted at an auto body shop ($250).  But this will be my final step and there is a lot more to do before I get there.

Next time, I will discuss the influence of Converse All Star sneakers on my design.

Minne Faire 2011 – Call for Makers

I would like to announce that we have selected Sat. April 9th to be the date for this years mini maker fair. The Faire will take place from noon until 5pm and there will likely be some sort of after party. Mark your calendars!

This is also a Call for Makers. We need you to fill tables at our event.  If you’d like to request a table please e-mail jtbarclay@gmail.com with a description, link, and/or photos of what you’d be presenting.  Also include your table size and power requirements. Since the Hack Factory has filled up quite a bit since last year, space is at a premium.  We are working with our landlord to free up some extra space for the weekend, but tables will be limited. If needed, table selections may be a juried process.

If you haven’t been to the Hack Factory since last years faire, I recommend you stop by.  Our membership has increased substantially over the past year, and the difference you’ll immediately notice is the presence of tools!

Minne-Faire: Feb 13th, 2-11 PM at the Hack Factory

Twin Cities Maker is going to have a Mini Maker Faire at the Hack Factory on February 13th, 2010! Come one, come all! We’re planning to have the fun start at 2 PM with local makers exhibiting and playing in the newly acquired space. We will also have an Art Show and Party later that night for people to come and experience the space and have some refreshments.

We are looking for you to join us and we are also looking for people to exhibit! If you’re interested, please contact us at twincitiesmaker@gmail.com so we can reserve a spot for you! Also come to our regular Wednesday night meetings if you would like to help us out or get some ideas for your table.

ADMISSION IS FREE!

There will be raffles throughout the day for maker stuff. Light refreshments will be provided at the art show and party.

Makers for the day include:

  • Tim Kaiser – Hands-on music, plus a performance
  • Joseph Rand – DIY Wind turbine
  • Ed Vogel – Displaying of super cool electric cigar box guitars
  • Stefan – Showing off some amazing air cannons
  • Replica Prop Forum – Replica movie props
  • Adam Wolf – Display and playing with Arduinos
  • TC Maker sign-up table – Join and become part of the TC Maker community
  • TC Maker’s tables to show off your stuff!
  • Pat Arneson – Noise toys
  • Tripoli Minnesota Rocketry Club
  • Meg Koslowski and Andy Rennert – Art cars on display! Transform the thing you drive into something that is a work of Art!
  • Nick and Jim of TC Maker – Presenting a life size “Operation” game complete with red nose!
  • CazTek – Featuring flame throwers and pulse jets and other fun engineering feats!

Please join us to support the Hack Factory and local makers by becoming a member or making a donation.

Hack Factory
3119 E 26th St Minneapolis, MN 55406

Mini Maker Faire 2-6 PM
Art Show & Party 7-11 PM

Refreshments are being provided courtesy of CazTek Engineering , a local design and engineering firm.

Click one of the images below to get a full page PDF copy of a promotional flyer.

Tim Kaiser    ?    Hands-on music, plus a performance
Joseph Rand    ?    DIY Wind turbine