Securing the Rubber Mounts on a paramotor

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0><tr> <td valign="top" colspan=2 height=80 BGCOLOR="#000000" TEXT="#F7F7FF" bgproperties="fixed" background="04100500dvldtc.png"> <div> <B>Securing the  Rubber Mounts on a paramotor</B></div> <div> <B>                                                    Article by Alex Varv</B></div> </td> </tr><tr> <td valign="top" width=216 BGCOLOR="#FFCC66" TEXT="#080000"> <div> <B>  </B><B>   </B></div> <div> <B><IMG SRC="e4ac3a20.jpg" border=0 width="195" height="162" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></div> </td> <td valign="top" height=400 BGCOLOR="#000000" TEXT="#F7F7FF"> <div> <B>Rubber mount failures have been known in ultralight aviation.</B></div> <div> <B>However, they do not occur too often. But when they happen, catastrophic destruction may occur to the aircraft or/and  people around.</B></div> <div> <B>Recently,  a rubber mount failure occurred on a paramotor and this fact determined me to write this material.The damage was substantial  but with no victims. After the rubber mount separation, the engine was sheared off the frame. The pilot was still on the ground.</B></div> <div> <B>We will not publish the damage, except the rubber mount separation so this can be an awakening call for those who do not include a rubber mount check in their pre-flight inspection.</B></div> <bR> <bR> <bR> <div> <B>       <IMG SRC="e4934d40.jpg" border=0 width="564" height="468" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></div> <bR> <div> <B>In order to avoid such damage I strongly recommend the following:</B></div> <bR> <div> <B>1) Use only factory approved (and tested) rubber mounts</B></div> <div> <B>2) Install safety straps around the mounts that would still hold if there is a separation as shown in the picture above.</B></div> <div> <B>3) Install the #5 engine mount under any engine if possible. I understand that this involves more work but the engine being sustained from underneath will NOT flex down as easily in the case of an impact with the ground and this additional support will reduce some stress from the  (especially) upper engine mounts that due to the engine weight are pulled apart in contrast with the lower mounts that are squeezed together.</B></div> <div> <B>The # 5 engine mount, will obviously prolong the life of the other 4 engine mounts as well.</B></div> <bR> <div> <B>Below, we will concentrate on point # 2 (above) and show step by step how to make and install the safety straps around the engine mounts.</B></div> <bR> <div> <B>Note: </B></div> <div> <B>There are two types of rubber mounts: male and female type.</B></div> <div> <B>Below, we will show how to install the safety strap on a female type rubber mount.</B></div> <bR> <div> <B>The picture below shows what materials and tools are required (self explanatory)</B></div> <bR> <div> <B>                <IMG SRC="e4d08750.jpg" border=0 width="520" height="373" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></div> <bR> <div> <B>Cut the webbing with a pair of scissors, sharp blade or hot knife.</B></div> <div> <B>The advantage of the hot knove is that we will not have to melt the cuts.</B></div> <bR> <bR> <div> <B>                  <IMG SRC="e4ff7790.jpg" border=0 width="503" height="377" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></div> <bR> <div> <B>Put the webbing on the rubber mount , center it and using a sharp tool make a pilot hole in the webbing.</B></div> <bR> <div> <B>                  <IMG SRC="e66f4770.jpg" border=0 width="500" height="375" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></div> <bR> <div> <B>Next, using the soldering gun, enlarge the pilot hole slightly larger than the bolt that will have to pass through it.</B></div> <bR> <div> <B>                   <IMG SRC="e7af4770.jpg" border=0 width="500" height="375" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></div> <bR> <div> <B>          </B></div> <div> <B>                   <IMG SRC="e68f4770.jpg" border=0 width="500" height="375" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></div> <bR> <bR> <bR> <div> <B>                   <IMG SRC="e6af4770.jpg" border=0 width="500" height="375" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></div> <bR> <bR> <bR> <bR> <div> <B>                    <IMG SRC="e6cf4770.jpg" border=0 width="500" height="375" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></div> <bR> <bR> <bR> <div> <B>                    <IMG SRC="e6ef4770.jpg" border=0 width="500" height="375" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></div> <bR> <bR> <bR> <bR> <div> <B>                   <IMG SRC="e70f4770.jpg" border=0 width="500" height="375" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></div> <bR> <div> <B>                    <IMG SRC="e72f4770.jpg" border=0 width="500" height="375" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></div> <bR> <div> <B>The above pictures show the simplest way to secure the rubber mounts.</B></div> <div> <B>We can install a second strap to increase strength by 50%.</B></div> <bR> <div> <B>                   <IMG SRC="e74f4770.jpg" border=0 width="500" height="375" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></div> <bR> <bR> <bR> <div> <B>                    <IMG SRC="e76f4770.jpg" border=0 width="500" height="375" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></div> <bR> <div> <B>When wrapping around the second strap, we can hold the  end in place using a small vise-grip. This is why the strap in the above picture is a little longer reaching past the rubber mount.</B></div> <bR> <bR> <div> <B>                   <IMG SRC="e7cf4770.jpg" border=0 width="500" height="375" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></div> <bR> <div> <B>Again, using a vise-grip we can secure the strap while installing the bolt.</B></div> <div> <B>Sometimes, with all the precise measurements we take, the holes in the strap may be a little off. We can correct this using the soldering gun to melt or elongate the hole for a better fit.</B></div> <bR> <bR> <div> <B>                  <IMG SRC="e7ef4770.jpg" border=0 width="500" height="375" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></div> <bR> <div> <B>Now that everything has been fitted on the rubber mount, we can proceed installing it.</B></div> <div> <B>I advise that first we install the mount and the strap on the engine side and then, we put the engine on the frame.</B></div> <div> <B>To keep both holes in the strap aligned, we can wrap electrical tape around the rubber mount having the straps aligned with the holes.</B></div> <bR> <div> <B>The above illustrations refer to the female type of engine mounts.</B></div> <bR> <div> <B>If your paramotor has male type of mounts, all you need to do is to melt a hole in the safety strap and fit it directly on the threads of the rubber mount.</B></div> <div> <B>The second fit will be a little tricky so you will have to estimate where the hole should be but keeping in mind that a loose safety strap will be less efficient.</B></div> <bR> <div> <FONT SIZE="3" COLOR="#00FF00" FACE="Arial" ><B>Final note:</B></FONT><FONT SIZE="3" COLOR="#FFFF00" FACE="Arial" ><B> </B></FONT><B>What most people do not know is that the rubber mount </B><FONT SIZE="3" COLOR="#00FFFF" FACE="Arial" ><B>MUST NOT</B></FONT><B> have any torque built into it.</B></div> <div> <B>In other words, when we finalize torquing the nut (on the male type) or the bolt (on the female type) we will notice that trorquing will cause the rubber mount to turn!</B></div> <div> <B>If we let this happen, we will build permanent tension in the mount which obviously, will weaken the mount in time. To prevent this from happening, we should hold the rubber firmly with one hand. </B></div> <div> <B>Another very efficient way is to put some rubber cement on the metal of the rubber mount and on the safety strap. The glue should be let to dry and after that, we can install the engine mount.</B></div> <bR> <div> <B>Using the above methods, we will have our rubber mounts secured and in case of a separation  -signaled by increased vibrations-  hopefully, we will be able to land without any damage to our equipment.</B></div> <bR> <div> <B>Please, fly safely !</B></div> <bR> <bR> <bR> <bR> <div> <B> </B></div> <div> <A HREF="index.htm" TARGET="_top" TITLE="_"><U><B>Back to HOME</B></U></A><B>                                                                  </B><A HREF="id29.htm" TARGET="_top" TITLE=" The Inventions Page"><U><B>Back to The Inventions Page</B></U></A></div> <bR> <bR> <bR> <bR> <bR> <bR> </td> </tr></table></body>