• Angry
  • Awesome
  • Hungry
  • Secret
  • Results 1 to 9 of 9

    Thread: DIY: My experience with fiberglassing the firewall

    1. #1
      Do you really want it?
       
      Awesome
       
      autohead's Avatar
      Join Date
      Jan 2011
      Location
      Bengalooru
      Posts
      1,109

      DIY: My experience with fiberglassing the firewall

      Hello guys, I wanted to share my first experience with fiberglassing.

      As usual, my hands were itching to do something on my guinea pig, our m800. After damping all the doors with a combo of damping material and yoga mat I wanted to insulate the firewall and the hump that has the exhaust pipe underneath from a long time. I wanted more of a heat insulation rather than sound rejection. Recently there was a short circuit of the ignition wires that led to lot of smokes and occasional sparking and smoke during driving. This was courtesy the autocop installer who had sliced several wires in order to identify them and left them uncovered. It held well until I messed with other wiring. Anyways, I took this opportunity to remove the entire dash to cleanup all the wiring.

      This was also a chance I could do some damping for the firewall. Did some research and found that I had not many options. I was not sure if the regular damping material would hold up to the repeatedly cycles of heating and cooling. And those professional damping materials that can withstand temperatures would cost much and I am not sure about the availability either. Listing out commonly available materials that would do good heat rejection with a good enough density did not yield much. Closed cell foams could achieve it but I would have to use a really thick foam which I did not like it. And again I don't know if the regular synthetic glue like fevicol sr could hold up the frequent heat cycles. Then I thought about fiberglass. It has excellent heat rejection property and I could build up the density by layering it up as much as needed.

      Went ahead and bought 4kgs of fiberglass mat, a bottle of hardener and accelerator each from commercial street. It cost me 1.2k. Bought 5 liters of thinner, 5 paint brushes, a couple of pair of medical rubber gloves and a 10ml syringe. Then the process started. I never had done fiberglass before and all my preparation was based on google search results. I cut up the fibreglass mat into lots of small and medium size pieces. I had planned to apply them as we usually do for damping. Cover the surface with small pieces and then build up layers similarly. I prepared the first batch of mix after reading somewhere that the ratio had to be 10 parts hardener and acclerator to 100 parts of resin. Used the syringe to measure the 10ml.

      Excited, I stirred it up nicely and was about to apply it to a piece of fiberglass when I noticed that the plastic cup was getting warm. Since I was expecting it I did not give it much thought. In a couple of seconds the cup turned from warm to hot and then really hot. I could not hold it any longer and placed it on the floor. And a second later it was bubbling, sizzling and smoking. And that smell killed half my excitement. It was just plain disgusting. Then it was the turn of the brush I had dipped it in. It started smoking and sizzling too. By this time the plastic cup was toast, had melted in the heat and there was one big chunk of solid glass like thing. Picked up that piece of glassy thing and it was still very hot. Threw it out along with the brush that had become equally hard. Feeling foolish I tried mixing other ratios and wasting lot of resin till I came up with the magic ratio of 2.5 ml hardener and accelerator to 100 ml of resin. It gives around 5-7 mins time before it starts to harden. You can go up to 4ml per 100ml but you will have to be quick. And if you screwed the ratio AFTER the mixing is done (more hardener) use it up real quick before it hardens. Do not add more resin or try to dilute if with thinner. If you find the hardener is less trying adding a bit more accelerator. Avoid adding either hardener or resin once you have mixed them thoroughly. It just won't work properly. I suggest you keep using small batches of 100ml each time. That way you can even throw out mixture if the ratio goes bad.

      It was fun initially and went smoothly in the beginning. The wheel well and the slope of the firewall held the wet fiberglass well. But as I progressed up the firewall where I had to stick it underneath the horizontal panels it became a pain. It would just drop off and I could not hold each piece long enough to harden. The mixture and the paint brush would harden as well. Did a lot of circus and finally covered all as much as the area as possible. I put 3/4 layers of the fiberglass mat. It felt hard as a rock and thick enough after drying. There were lot of other painful things too. Each time I had to take a break it meant that the paint brush would harden up and be useless. The gloves I was wearing would also had to be thrown, there was lot of stickiness everywhere, skin burning from the resin seeping through the gloves, the whole area was messy, etc. And the cramped space inside did not help either. There was a time where I regretted taking up this project. However continued with it and completed it to my satisfaction. It took me almost 15-17 hours to complete the firewall itself.

      The hump on the floor was relatively easier. I was able to complete it within 4 hours. But that time I had got lot of experience and helped me do it fast, clean and efficiently. Finally started cleaning the mess. Though it was exhaustive it was welcoming too. It meant that the finish was near Used lots of thinner to clean virtually every inch of the firewall, the wirings (resin had dropped on almost all the wire and had become ugly and very sticky). Finally gave the interior a bath of strong solution of surf and dried it.

      Then took up the task of cleaning up the wiring. Everywhere there was lots of ugly stick tape getting unwound and trapping lot of dirt as well. Yuck! Our so called electricians can never come to term using anything else for insulation I guess. I bought a bundle of non adhesive PVC tape and started the work. You just wind up the tape really really tight over the wires and it's done. The tape sticks to itself by the virtue of it's surface when wound tight enough. It's really simple and no nasty sticky goo. However you need to wind it so tight that my finger started to pain and became weak. From that time I just started to do a simple knot at after the winding. It holds good enough too. Easy to remove as well if required. Oh and I also did some cheap sound damping to the air vents and the interiors of the blower using the common open cell foam available in the upholstery shops. Finally it was time to put everything back together. Spent a day routing the wires properly and fitting the dashboard back.

      The car started happily at the first crank and everything was fine. So after all these did all the effort pay off? It's a mixed response. There is a tremendous change in the heat generated from the floor and firewall. I can now keep all windows closed almost 80% of driving alone during a hot mid day. Before it was that I had to keep the windows all the times open. Both the observations were made within a month and since bangalore is now as good as summer during the day I guess it's not comparing apples to oranges. I know this is an obscure way to measure the ambient temperature but I did not bother to check it properly since the difference was obvious. The sound insulation for the lower frequencies has not improved much. I guess the density of the fiberglass is not enough. But there is a definitive improvement in rejection of higher frequencies. The fan hum, the red grills and the higher rpms now sound lot less inside the cabin. And the blower sound has reduced a bit too. I could say around 25-30%. No more annoying whoosh... sound. Overall, satisfied with the effort. Total amount spent around 2.2k.

      Here are a couple of pics of the fiberglass WIP:

      Click image for larger version. 

Name:	IMAG0063.jpg 
Views:	79 
Size:	343.7 KB 
ID:	115228

      Click image for larger version. 

Name:	IMAG0064.jpg 
Views:	67 
Size:	331.0 KB 
ID:	115229

    2. #2
      Do you really want it?
       
      Awesome
       
      autohead's Avatar
      Join Date
      Jan 2011
      Location
      Bengalooru
      Posts
      1,109
      Oh yeah, forgot to mention one thing. I had contemplated that the firewall could flex a bit and over time could lead to the fibreglass peeling off. Since the fiberglass is effectively one large piece any peeling at one end could trigger a cascading effect. In case that happens I plan to cut up the fiberglass into 5-6 chunks and restick it with some more resin. That way it should solve the issue. Also I have installed a strut bar and hence I think this issue would not be a major concern for now.

    3. #3
      Jai Radhe Maa
       
      Secret
       
      007's Avatar
      Join Date
      Jan 2010
      Posts
      5,814

    4. #4
      Rabid Dog Club
      Giving excuses!
       
      Awesome
       
      camchennai's Avatar
      Join Date
      Nov 2010
      Location
      City of Super Kings!!!
      Posts
      10,231
      Respect your patience and time
      Toyota Camry MT|TATA Safari EX 4x2

      Rabid Dog Club - bite first, bark later :-P

      “The auto industry is not a charity that produces widgets for driving enthusiasts.”

    5. #5

      not aware that he can set his status here!
       
      Awesome
       
      sriharsha's Avatar
      Join Date
      May 2010
      Location
      Bangalore
      Posts
      2,914
      That's some brilliant work there autohead. Kudos!!!

    6. #6
      not aware that he can set his status here!
       
      Hungry
       
      bamaboy's Avatar
      Join Date
      Mar 2011
      Location
      MH 31 ; CG 10
      Posts
      2,730
      Excellent DIY, autohead!
      Salute to your hard work and patience.
      2015 Mercedes-Benz C200 Avantgarde
      2016 Hyundai Creta SX(O)
      2017 Isuzu D-Max V Cross: PX5 Android HU -> AK4490EQ -> miniDSP C-DSP| Helix P400 | Kravchenko KAXBLTWT & HAT Legatia L6SE | Boston GT2125 | Vaani Vector 6.5mkII | SounDigital SD250.1| Infinity REF1200S
      2014 Hyundai Elite i20 Asta: Nexus 7 -> AK4490EQ -> miniDSP C-DSP| DLS A2 | Audible Physics RAM3a | Boston GT2125 | Vaani Vector 6.5mkII | Rockford Fosgate T400-2 | Morel Ultimo SC

    7. #7
      Jai Radhe Maa
       
      Secret
       
      007's Avatar
      Join Date
      Jan 2010
      Posts
      5,814
      not just this guys, take a look at these too:

      Best place for vacuum on the intake manifold
      DIY: Slotted my own brake rotors

      true DIY enthusiast right here. autohead does his handle justice. again,

      next time I'm in Bangalore, we should catch up man.

    8. #8
      Do you really want it?
       
      Awesome
       
      autohead's Avatar
      Join Date
      Jan 2011
      Location
      Bengalooru
      Posts
      1,109
      Thank you guys. It's gives me great satisfication to create or put together something new. Though many people doesn't even consider a m800 to be worthy of being called a car, this is the only car that I can literally rip apart and put it back, the only reason I am holding on to it still. Also it shows many people here really are autoheads like me, appericiating and joining in the spirit instead of judging or dismissing something by it's face value

    9. #9
      Jai Radhe Maa
       
      Secret
       
      007's Avatar
      Join Date
      Jan 2010
      Posts
      5,814
      Quote Originally Posted by autohead View Post
      Though many people doesn't even consider a m800 to be worthy of being called a car, this is the only car that I can literally rip apart and put it back
      and you love the car all the more for it.

      Last edited by 007; 21st Nov 2012 at 23:08.

    Thread Information

    Users Browsing this Thread

    There are currently 1 users browsing this thread. (0 members and 1 guests)

    Similar Threads

    1. Your scariest driving experience !!
      By Babbanji Franklin in forum Traffic Lights
      Replies: 190
      Last Post: 18th Mar 2018, 08:38
    2. My first ever ICEing experience! Help needed
      By badri in forum Equipment & Install Queries
      Replies: 23
      Last Post: 16th Dec 2011, 17:14
    3. Ownership experience - VW Polo
      By Trojan in forum Polo
      Replies: 67
      Last Post: 12th Jul 2011, 21:29
    4. Replies: 28
      Last Post: 9th Dec 2010, 08:48
    5. My 200 km experience with Tata Nano LX
      By aravindhan in forum Nano
      Replies: 7
      Last Post: 14th Jul 2010, 11:14

    Bookmarks

    Posting Permissions

    • You may not post new threads
    • You may not post replies
    • You may not post attachments
    • You may not edit your posts
    •