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Kit #7 arrived

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  • spinningwrench
    replied
    It worked well for me to start at the top of the boot cowl and work down progressively tightening it up and clecoing to the firewall and to the formers. I did it all with poster board to begin with then transferred to aluminum once it fit.

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  • Utah-Jay
    replied
    Originally posted by spinningwrench View Post
    Did you verify your predrilled firewall bolt holes were at the correct location. Mine were off from the factory on my Quickbuild and I had to replace the first firewall.
    NOPE

    I assumed they were in the correct location. I will measure things out when I put it back on as I am waiting on the heat shield adhesive to dry and trying to figure out the puzzle pieces of the boot cowl. I can’t get my head around it even with them laid out on the hanger floor
    Last edited by Utah-Jay; 10-31-2021, 05:33 PM.

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  • spinningwrench
    replied
    Did you verify your predrilled firewall bolt holes were at the correct location. Mine were off from the factory on my Quickbuild and I had to replace the first firewall.

    Leave a comment:


  • Utah-Jay
    replied
    Ejs014
    My “mentor” has used this method on both his Rocket and currently Carbon Cub, he claims that between the adhesive, engine mounting bolts and all the pass through items on the firewall it is all fine. It has been used and done successfully before. The Koolmat is on the backside (cockpit side) of the firewall.

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  • Ejs014
    commented on 's reply
    Thanks. After I asked I started reading about koolmat on the ACS link you had in the post. FWIW they recommended a 3M fireproof 2000 sealant for installation. I'm not sure if the 3M 77 will hold up to any substantial temperature but I suspect for the engine side the mechanical fastening of the firewall to the frame and anything else you add to it will hold the mat in place. Maybe it will on the interior as well? I do know it will be hard to redo after the engine is installed so I would be sure it is going to stay in place. I think if you look at most certified installations you will find mechanical clips with no adhesive.

    This really got me thinking and I probably couldn't sleep knowing I didn't at least mention this so here are some points to consider.

    It's hard to say how hot a firewall gets in normal operation and I am not sure of the heat differential from the hot face to the cold face of the material you are using. A firewall is typically rated for 2000 degrees for 15 minutes per FAA standards. You can think of that as a direct flame on the firewall at a set distance. Aluminum melts at 1220 for comparison. If you put anything on the firewall that can't stand up to that temperature without melting, smoking or catching fire you have essentially derated the firewall capability. It's a bad situation if you ever have a engine compartment fire and it will be even worse if the firewall keeps the flames out but the cockpit fills with smoke or flames from something else at a lower temp. In normal situations this will not ever come into play but it certainly has the potential to make a bad situation worse.

    You could do a test with the scraps and adhesive to see if it produces smoke or lets loose. You don't want it falling into your pedals either.

    You may already know all of this and have thought through it, so just ignore me thinking out loud if that's the case. It will not be the first or the last time I overthink something! LOL

    Keep up the good work and happy building!

  • Utah-Jay
    replied
    Ejs014
    It’s the one on the right in this photo.
    7106F7DB-B84A-4819-97F9-2327B9BBA96C.jpeg

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  • Ejs014
    commented on 's reply
    Jay, what adhesive are you using? Does it need to be rated for a certain temp?

  • Utah-Jay
    replied
    Worked the firewall’s heat shield and sound dampening today, had to make a template for both the front and the back of the firewall.
    EFC238B0-614A-4798-8748-3CAEE55A1030.jpeg
    103B5AE9-5545-41D7-8B9A-ED57C84761D8.jpeg And then the spray adhesive and clamping. This is the inside the cockpit sound dampening material is from ACS: https://www.aircraftspruce.com/catal...es/koolmat.php

    BE5B0C9F-E6C0-4251-822A-2D024872D899.jpeg
    The heat shield is from Amazon and will be put on in tomorrow:


    Tomorrow the panel and boot cowl project begins

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  • Utah-Jay
    replied
    Firewall all mounted, another job not easy doing solo
    1968F53F-6044-4A2A-9173-B193372A90F1.jpeg Now that I have it all drilled and mounted, I will attached the fabric to the front and back for heat and sound reduction.

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  • Viking
    commented on 's reply
    Ive only ever seen those click bond nutplates used for bonding to composites. If the adhesive is good for bonding to metal, it should be quicker than riveting nutplates for sure.

  • Utah-Jay
    replied
    She has legs
    766F43E3-E10A-4076-8E9F-5A84BB4B3B64.jpegA577E3F5-376F-4EC3-86EF-23ED1862B0CF.jpeg

    Not a particularly easy job to do solo.

    Took me the whole day

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  • robcaldwell
    commented on 's reply
    Sure thing, Jay. Here is more on the subject: https://bearhawkforums.com/forum/bea...t-for-fittings

  • Utah-Jay
    commented on 's reply
    Yikes, thanks Rob

  • robcaldwell
    commented on 's reply
    Jay, it appears that you are using thread sealant on your 37 degree flared fuel line fittings. Thread sealant should not be used except on NPT fittings. Only then very sparingly. You do not want that stuff getting into your fuel system. You may need to remove those lines and rinse out the sealant.

  • Utah-Jay
    replied
    Wrapped up a lot of stuff that I had been working on and preparing to be finished. No big stuff today.

    Finished up the fuel system and all the connections are sealed, the line under the door former is held in place by a double adel clamp.
    66E7A6DC-4745-4289-B870-8CC330239218.jpeg4CCB4A56-3C94-4942-AF9D-6CBD88EF1E8D.jpegCFEB1672-02E7-4086-A2C3-8DB820697D0F.jpeg
    Yep, there are scratches. I am looking into laying 0.060 Kydex down on all the floorboards. Will know next week.

    I installed a cover for the open area around the flap handle. Still not sure what I am going to do around the back of it.
    87E794FE-95C1-4A2D-83FA-1296818A64FD.jpeg
    ELT tray got final install. A lot of this was due to the Adel clamp pliers finally arriving
    ED0EF88F-C15C-42D2-A096-914E01326CC0.jpeg I put a spacer in the connection of the upper turnbuckle and the elevator bell crank.
    787ACA42-5A4C-4155-B56C-CDB1D505084A.jpeg

    There was not much sexy about today, here is a look at the tools and stuff on the floor where I spent a good portion of the day. B16E1311-8D51-423F-B3CE-F6A4FCECDE8E.jpeg I am getting close to attacking the control surface permanent wires/cables.

    At this point I am waiting on stuff that is stuck in the supply chain delays which is no fun. I need to get the plane on gear so I can mount the firewall and start in on the boot cowl. I could mount the axles on wood blocks, but that would then require removal when the brakes and wheels arrive. If I have to I will, but still waiting it out doing other tasks.

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