Here is the latest with the new dimensions. Still needs some minor
 tweeks here and there.

 Paul Lamar


 Paul what is the plan to split the cowl [vertically or
 horizontally? Connection type?

 Are we just making a foam buck over which Mark is going to lay up
 glass and then
 hack out the foam?

 Jarrett

 I think it is best to split it horizontally for service reasons.

 The foam buck however could be split vertically as then you would
 have a mirror image. I can do the 3D either way.

 ops I forgot to answer the connection type.
 The bent piano hinge trick is popular.
 The top is held together with a piano hinge.
 You remove the wire to separate them.

 Paul Lamar


 Alrighty, we can split it either way.. I imagine it would be
 shorter if
 we split it vertically thru the
 spinner? I'm still a little limted in 'Z' depth so the shorter
 it is in this dim the best..

 Interior ducting can easily be done either as a buck or a female
 buck/mold. Either will take a little
 to finish as they wouldn't be true 'mold's [as in waxable..] Mind
 you I can do that as well..just
 takes more time and some more exotic materials..

 It's been a few years since I used Rhino.. does it have zebra
 curves to check the surface smoothness,
 and blends across joints [curvature continous curves across joint
 lines]?
 I'll have to send some pic's of parts I've made like this on
 the mill...  did a world record setting kayak
 two years ago...

 Jarrett

 I think we can use insulation foam and cover it with saran wrap
 and scotch tape.
 The imperfections would be easy to sand off the buck.

 The short way would be a horizontal split as the total cowl
 is only 31 inches high while it is 46 inches wide.

 No zebra curves as far as I know but people tell me it will load into
 Solid Works.

 You do the whole thing and then split it on a plain.


 Paul Lamar

 Sure Paul, I can give it a whirl... can I get you to send me what you've
 got so far [model or dim's] and I'll play w/ it from there? Your correct,
 Sw can open Rhino files directly if you want to go that route.

 Jarrett

 I need to do some more tweeking.


 Paul Lamar

 Paul,

 The tunnel on the firewall has straight sides.  The roof is streamlined
 to
 encourage airflow through the tunnel.  The cowl portion is basically a
 half-circle, as shown in these pictures of an ES cowl (not mine).  I feel
 that my installation would benefit from slightly larger tunnels than
 these
 in order to improve exit airflow.

 Mark S.

 What is the thinking on these? Theory?

 It is not obvious to me.

 Paul Lamar


 That's how the heated air gets out of the cowl.  It is also normally
 where
 the exhaust exits.  The attached picture shows the two tunnels and the
 cowl
 flap of my current design.

 Mark

 Nice picture Mark. Do you have a large radius on the lower edge of the
 firewall just above the flap?

 Paul Lamar

 Paul,

 No, I didn't at first, but I did add one later.  Every little bit helps.
 I'll see if I can get a picture of it for you.  It is basically a thin
 piece
 of aluminum bent into the shape of an upside down question mark and
 attached
 to the lower firewall lip.

 Next, I would like to add sides to the cowl flap.

 Mark

 That sounds OK.

 I think I figured out the reason for those two tunnels.
 It is an attempt at dual augmenters... AKA exhaust ejectors.
 Since the AC engine has dual exhaust it makes sense to try
 to do this. In our case there is just not enough room IMHO.

 Paul Lamar


 Paul,

 I'm not so sure about that.  Most of the Lancair guys run the exhaust
 pipes
 out through the exit holes far enough so that the exhaust doesn't soil the
 belly.  I think the tunnels are there to help scavange the heated air out
 of
 the cowl at an angle close to the relative airflow across the lower fuse.

 Mark S.

 Well then they should :)

 Check out an early Cessna 310 it has real augmenters. I have a picture
 around here
 someplace. Of course in the ES one would have to have SS tubes in there
 to keep the composite from melting.

 I like the side flaps idea. One on each side or just one on the right
 behind the rad. Six inches wide by about 20 or 25 inches high.

 Paul Lamar


 Paul,

 Side cowl flaps won't work because the end of the radiator will be up
 against the firewall.

 Mark

 Are you sure? You have 51 inches from the top of the firewall to the
 spinner while the rad is 28 inches long as I recall. Let me do a top
 view rendering of what I have so far.

 OK here it is. Lots of room!

 In general you cannot move the side rads all the way back because of
 the motor mount. I have a dwg someplace of your current MM so I have
 to add that in.

 I still need the thrust line position down from the top
 of the firewall just as a reminder.

 -------------------------------------------------------

 Does this motor mount look about right?
 What I don't have is the exact shape of the firewall
 which we will need to make a buck. If you give me the coordinates
 of one side and I can take it from there.

 BTW how did Lancair resolve the MM cracking issue?


 Paul Lamar
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 Paul,

 The drawings are missing the width dimension on the radiator.  I agree
that
 if I use a 13" - 14" wide radiator, that it would fit with ease.  But I
was
 shooting for a larger radiator, more like 19 x 29.  Based on the present
 cowl dimensions, a radiator of that size would need to be tilted about 20*
 in order to fit inside the cowl, with the rear being very close to the
 firewall.  The further forward you move it, the less room, the further
aft,
 the more room.  Tilting it a little is OK as it makes it easier to get to
 the spark plugs and work on the engine.  The portion of the cowl just
below
 the spinner appears to be larger in comparison to the present cowl.  With
 my
 current cowl, the tunnels are far enough forward, and are spaced so as to
 provide some extra room for the radiator.  Without them the radiator would
 hit the forward barry mounts. The radiator end tanks fit down into pockets
 formed by the tunnels.  I was counting on the tunnels for a little extra
 room for the fore/aft radiator design.

 The motor mount you have shown looks real close to the Lancair mount that
 came with my kit, except there is some bracing missing between the two
 lower
 firewall points (see pic).  There should be a total of 5 firewall anchor
 points.  The fifth one is between the two lower ones, and up a little.  It
 provides additional support for the "wishbone" that prevents the nose gear
 from folding back.  I'm pretty sure the ES uses the same motor mount as
the
 Lancair IV, which has retractable gear.  The ES has fixed gear, so the
 wishbone replaced the hydraulic cylinder used on the IV.  Lancair hasn't
 come up with an "official" fix to the cracking problem as yet, although
 they have gone to a different nose strut.

 Mark

 Scale the dwg and you will see that it is 18 inches. Anyway there is
 room in there for the 20" by 32" Dodge pick up rad.

 I need a good dwg of the firewall as the current 3D's are too wide at the
 bottom.
 I agree with the tilt. I can put the tunnels in there as long as they are
a
 part
 of the firewall dwgs.

 I don't need the detail on the motor mount back there. I need the
dimension
 between the two front rubber bushing center to center.

 It is not a good MM design but it is good enough to not need replacing :)

 I can also cut down on the height of the cowl near the front. There is
 room to do that.

 Paul Lamar

 Paul,

I was at the airport today and measured the top of the cowl to the
eccentric
CL.  Best I could measure it is 12 5/8".

I forgot to measure the front motor mount dimension.  Keep in mind that
these are angled inward and aft, so where do you want the measurement
taken?
Mark

About the center of the mount. No need for great accuracy I just want
to make sure the Lincoln rad you have will fit without poking through
the cowl. How about outside to outside.

Paul Lamar


Paul,

OK, I should be back out there tomorrow and will get the measurement of the
front motor mount.

Mark