Jump to content

Temperature required for Aeropoxy

A Bruce Hughes

Recommended Posts

The winter newsletter on page 19 contains a short discussion of a problem that I encountered in finishing a Longeze.  It should have been clear.   Maybe an edit made it confusing.   I used Aeropoxy on Maui where the temperature is pretty constant and high.   So no problem until the project was shipped to my wife's hangar 25 miles from Olympia.    I had to build a workshop in one corner of the hanger large enough to fit the project into.   I could heat it electrically so no problem.   

BUT testing time came around and I MOVED IT TO A HANGAR AT Olympia Regional Airport.   It was ready to fly and did for 45 hours.........................

The problem came when I wanted to make a change on the turtleback using Aeropoxy.

The hangar at Olympia is not heated and cannot be heated more than five degrees above the outside temperature.    That means that there is NO time, even in July or August when the hangar is warm enough to set the Aeropoxy.   So I built a box which is 6'x6'x6', with a door for access,   Two pictures show the partially complete box.  Currently the box is ready but I am on Maui.   In April I will finish the job.   When in use, a heater will blow horizontally at the bottom, a fan will roll that air to vertical to make a circular rolling motion to the warm air.     The heater is thermostatically controlled and I have an indoor/outdoor temperature sensor to confirm the temp.   I think that will work.    The top and front of the box can be removed in seconds for access to the front.   There is room on each side of the propellor for a folding chair for access in the back.   The box sits entirely on the concrete floor, with a few ounces of force on top of each strake at the point where the fuel caps are.  I have many pictures of the box in construction and completed, if you are interested.    The point is that most of the U.S. is way too cold to use Aeropoxy without a box, a quilt or something.

Link to comment
Share on other sites

Hi Jeff

I would like to put the pictures on but I have no idea how to do that.

I have the pictures in my computer but will not have much help until April when my son or another guy can show me how.

The framework is really pretty simple:  2x2s for any vertical board, 1x2s for the other boards.   Then sheets of 4'x8' insulation from the Aviation section at Home Depot.   That makes a strong, light box.   The whole thing is bolted together with 1/4" bolts (3/16 bolts are generally too short).   Better to use one size of bolts even though that is overkill to avoid switching drill bits from time to time; that just wastes time.   I did have to use smaller screws for the hinges (door and 2 halves of the front surface).

Some horizontal 1x2 boards sit on top and directly underneath the strakes.   The strakes are curved and the board are not curved; I did not bother trimming for an exact fit.   Some fuzzy fiberglass pieces can be pushed into the empty space and/or the rigid 4'x8' foam pieces can be trimmed on curves to fit.

BTW   I have a Toyota Prius so the foam has to be trimmed to fit inside.   This results in 6'x39" pieces of foam when you drive to the hangar.  Then you have some scrap you probably never use.

The door has to be held in shape (90 degree corners) with an adjustable rod.   Watch out for threaded parts made of aluminum as the female threads immediately strip (why does Home Depot carry those?)(made in China, of course).   Use steel parts for anything threaded.

There are a few diagonal pieces just to make it structurally strong.   There are 2 short 1x2 boards that are padded with rubber sheets and sit on top of the strakes.

Those sit very close to the 2 fuel caps and sit at an angle so the boards are actually running along the top surfaces of the 2 strakes (but not far as those are short boards).

The top of the box is made of two 6'6" x 39" pieces of insulation which makes more than 6'.   I just put one 1x2 board on each piece to make it lighter.   Very small screws holds the piece above the propeller in place.   Gravity holds the other one in place.   It overlaps in the front a little.

The front above the engine/strakes is in 2 pieces on small hinges so the entire front can swing out to allow access.

The front below the strakes just fits very well against the strakes and rear of the airframe.   I have a NACA duct which is just filled with a couple of scrap pieces of insulation and fuzzy fiberglass.

Good luck.   I will send the pictures in April.   Don't think you need them.


Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information