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Modifications that you have Made to your RV-12 after Certification? E-LSA Only!

RV12 Problem with FALCON ELECTRICAL 14V ATTITUDE GYRO

Dear Andrew, I finished my RV12 in January 2014 in Lima, Peru, I purchased from Vans the Dynon skyview 10' package. Recently I installed a back up FALCON ELECTRICAL 14V ATTITUDE GYRO at the copilot side among other basic instruments. level indicator of the Falcon slips to a side indicatind a wrong airplane position every time I lower RPMs, or after 4-5 minutes with wings leveled. First I thought it was a problem of the equipment, however after replacing it 3 times the problem is still there.
I noticed the falcon requires more than 14v. and my Skyview indicates between 13.5v to 13.8v depending on the engine RPM. I took power supply from the Batery directly.
Can you recommend a solution to this problem, maybe take power from a different place or get a voltage booster??

Hope to hear from you soon, Best regards, Herbert
 
Another mod for increased air flow to the RV12 Voltage Regulator

See this thread for pics and details. The mod adds a "scoop" inside the radiator duct and supplies the VR from that, rather than from the existing location from the engine cylinder shroud supplied by the SCATT tube. (And also does not involve relocating the regulator to inside the plane.)

Testing proved substantially more air flow and the mod is easy.

http://www.vansairforce.com/community/showthread.php?t=126317
 
Here is a thread for putting a PVC pipe cap over the end of the flap handle pushbutton, secured with a screw, to eliminate any finger-pinching.

http://www.vansairforce.com/community/showthread.php?t=126733

Another idea. I wrapped the upper 2/3 of the flap handle with gray bike grip tape. The thick padded grip tape adds just enough to the diameter of flap handle. As such it works well to keep your skin away from the pinch point and looks nice at the same time! The grip tape comes it all kinds of colors and patterns.
 
One pinch is all it took for me to modify mine. Just chucked it in the lathe and took the "pincher" off!
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I further modified mine to work lots better in my opinion, you can see the no cost improvement here: http://www.mykitlog.com/users/displ...TX&project=2429&category=0&log=200630&row=137
 
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Handy little push/pull rod

This little "push/pull rod" comes in real handy in reaching the co-pilot air-vent handle when you're flying solo. Drill a #12 hole in the air-vent handle and you're in business.

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cold air curtain? When I did my 1st annual in 2012, I read a blog about what you mention. The cold air can come through the corrugated bulkhead due to the small openings. I had a foam mattress pad with the "bumps" which were triangular shaped. I cut them off and they fit nicely in the corrugation openings to block the airflow.
 
After the first few attempts to press the flap handle button, I press with the palm of my hand and then use my thumb hold the button depressed while placing the handle in the appropriate notch.
 
Rudder pedal extensions

My test pilot is a superb aviator but a little height challenged, so a few months ago I needed to make some rudder pedal extensions at short notice (no pun intended) so he could fly my plane safely. There are already a couple of very good extension designs on this thread, and Vans now sells a set for the RV-12, but I mentioned these home-made ones in another thread a couple of days ago, so here are the details.

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They are made from a piece of 12mm (about 1/2") pine, some bungee cord, ¾” angle offcuts, a few AN nuts, bolts and countersunk screws, plus a couple of spare WD-1211 Brake Pedal Torque Tubes that I had in my scrap bin. The pedals are 5” high, 4” wide at the bottom and 2 ½” at the top. They are 2 5/8” front to back with a 1” deep recess in the 2” high block. Sprayed up with rattle can paint and faced with some left-over wingwalk, they came out looking OK.

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The stub end of the torque tube arm slides into the brake pedal arm, the U at the bottom slips over the rudder pedal itself, the semi-circular cutout fits the vertical arm and prevents sideways movement, and the bungee holds everything secure. You could probably come up with a simpler alternative to the WD-1211’s, but I had them, so that’s what I used.

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They only took a couple of hours to make, cost practically nothing, and can be fitted and removed very easily. It’s also easy to set the face of the pedal at a slight angle if you find that the factory position is a little too upright to allow your feet to rest comfortably.

Note: A word of caution. If a pedal extension fails, you could be in serious trouble. I think this design is practical, safe and fairly durable, but it was made primarily for a short-term purpose (Phase 1 flying). You will need to make your own assessment of this or any other gadget or modification shown in this thread if it could affect flight safety. If I had a long-term need for pedal extensions, I'd probably buy the ones than Van's now sell.
 
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RV-12 Fuel Tank Vent



I posted this in another thread, but thought I should add it here also. I also made a large funnel with tight fitting into fuel fill opening. Between the two, it solves splash-back problems. Tubing is 1/2" I.D.
 
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Here is a mod to consider (from another thread but should be here) to eliminate unnecessary fuel tank removal. Rear bulkhead modification. Note: Match-drill the doublers BEFORE you cut the covers so that the pieces will remain in perfect alignment. The cuts maximize the openings. View the flaperon joint with mirrors (add torque seal paint). The doubler itself is
https:/

Do you have the measurements for the cut out as I have not yet made the tank but have all parts ready for pait and wand to make this mod before i pait the bullkhead

Hope you can help me

Regards

Christian
 
Likewise, and I dimpled for c/s screws to provide better mechanical interlock. Also added an angle stiffener across the back above the cutout. Probably overkill, but I can't help it - I'm an engineer :)

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Do you have the measurements for the cut out ?
 
carb. full throttle stop recommendation

This is what I sent to Vans Aircraft and to Rotax:

For the RV-12, referencing KAI drawing page 50-05 (revision 1), if the VA-219 throttle arm hardware assembly were not to be tightened sufficiently or become loose, the throttle arm spring will cause the throttle to fully open as designed by Rotax. By installing an additional CT-00101 stop on the throttle cable lead just past the VA-219 throttle arm hardware but not so close to the throttle arm to interfere with the throttle arm as I have done in the photos below, if the cable were to slip out of the VA-219 throttle arm hardware, the CT-00101 is a safety stop to limit the throttle arm movement and thus limit the throttle opening. This will eliminate the concern regarding undesirable and unexpected full throttle on either carb. by possible VA-219 throttle arm hardware slippage.

I came by this idea because of the difficulty in determining the proper amount of torque to apply to the VA-219 bolt and nut assembly. I found that too much torque caused the VA-219 assembly to not swivel properly during throttle actuation and too little torque caused the cable to slip in the assembly. If one errs on the side of loose and adds the CT-00101, if the cable does happen to slip in the VA-219 assembly, then the CT-00101 will arrest the throttle arm to only an approx. 1/8" of travel and no more.

I recommend adding the CT-00101 past the VA-219 throttle arm hardware assembly toward the end of each throttle cable lead for each carb. This modification is cheap. In fact, it cost me nothing since I had the CT-00101s as spares since I had my entire original throttle cable assembly as a spare when I went with the McFarlane vernier assist throttle. Also, (2) CT-00101s don't add much weight, but sure add a lot of peace of mind.

The issue of the VA-219 torque could possibly be eliminated if the length of the smaller diameter portion of the VA-219 Rotax step washer were longer and/or the Rotax flat washer were thinner. This could be a better solution as one could then tighten the assembly as much as the torque limit of the bolt/nut and probably never have to be concerned with slippage, Also, it does not add any additional parts. However, I never took the time to experiment with these changes.

Note that all of the above is to no avail, of course, in the unlikely event of a throttle cable lead break.

John Richard

RV-12, S/N: 120147

Photos were sent to Vans. However, I haven't been able to figure out how to post photos on this forum. I can send them via email to someone who can post them for me or directly to those interested.
 
This is what I sent to Vans Aircraft and to Rotax:

I came by this idea because of the difficulty in determining the proper amount of torque to apply to the VA-219 bolt and nut assembly. I found that too much torque caused the VA-219 assembly to not swivel properly during throttle actuation and too little torque caused the cable to slip in the assembly. If one errs on the side of loose and adds the CT-00101, if the cable does happen to slip in the VA-219 assembly, then the CT-00101 will arrest the throttle arm to only an approx. 1/8" of travel and no more.

John Richard
RV-12, S/N: 120147

Found the same. It is NOT possible to torque the VA-219 nut to the torque specified as it will not swivel.

Hoping Van's will take note and come up with a solution. John Richard, let us know how Van's responds,
 
The issue of the VA-219 torque could possibly be eliminated if the length of the smaller diameter portion of the VA-219 Rotax step washer were longer and/or the Rotax flat washer were thinner. This could be a better solution as one could then tighten the assembly as much as the torque limit of the bolt/nut and probably never have to be concerned with slippage,

This would not work because using the rated torque value for the bolt would severely crush the cable, effectively requiring it to be replaced if it was ever disassembled.

It should not be an issue anyway because by design the stepped washer is taller than the thickness of the throttle arm. The throttle arm should never become clamped between the plain washer and stepped washer. If you have seen that, then there was something not normal with the parts, or they were torqued so high that it actually compressed the thickness of the steel step washer (I am pretty sure that would require going way beyond the torque rating of the bolt).
 
The problem described (binding) may be due to a discrepancy between the maintenance manual and plans page 50-06.

Page 12-10, Step 10 in the maintenance manual calls for a torque of 15-20 inch lbs, plus the friction torque. (For me, this induced binding.)

Plans page 50-06, Revision 3, Step 2 calls for a torque of 8-10 inch lbs. (Don't really know if the friction torque should be added here.)

Scott?
 
The problem described (binding) may be due to a discrepancy between the maintenance manual and plans page 50-06.

Page 12-10, Step 10 in the maintenance manual calls for a torque of 15-20 inch lbs, plus the friction torque. (For me, this induced binding.)

Plans page 50-06, Revision 3, Step 2 calls for a torque of 8-10 inch lbs. (Don't really know if the friction torque should be added here.)

Scott?

Error noted.

Both documents should say 8-10 inch pounds.
I correction was issued a long time ago for this and I am pretty sure both docs were properly updated..... I will look into it.

Torque specs are always (in RV plans and manuals anyway) expecting the fastener prevailing torque to be added to the specified value.

FYI, the Rotax documentation prescribes that this point be oiled occasionally. The general recommendation is that when cowl is off for oil change, that you use the dip stick to apply a small drop of oil to the pivot point on the throttle arm.
 
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It should be noted that the Rotax flat washer is metric and not AN. The flat washer is a metric 5.5 (0.217"). So, if one were to lose the Rotax flat washer and put on an 1/4" size washer from the parts bin it would slightly override the step on the stepped washer and jam the assembly as well as ruin the parts.

I saw this on one RV12.
 
It should be noted that the Rotax flat washer is metric and not AN. The flat washer is a metric 5.5 (0.217"). So, if one were to lose the Rotax flat washer and put on an 1/4" size washer from the parts bin it would slightly override the step on the stepped washer and jam the assembly as well as ruin the parts.

I saw this on one RV12.

Good point Tony, but if someone does that they lack an understanding of how the pivot point is designed to work.... Since we use an AN3 bolt, you could replace a lost washer with an AN960-10 and it should work fine.
 
Rudder Lock

This rudder lock is made from a couple of rubber door wedges, two pieces of 1/8" diameter piano wire (hobby shop), a 3/4" block of wood, a piece of aluminium plate (cut from a scrap instrument panel), two rubber washers, a 3/16" diameter screw, washer and wing-nut, and a few plastic self-adhesive furniture pads. Paint the timber and add a couple of fluoro streamers and you're in business.

Drill a 3/32" dia hole about 3/4 of the way into the rubber wedges for the piano wires. The wedges should be level with the bottom rib in the rudder. The rubber washers more or less fit the round cutout at the front of the tail-cone slot, although the position isn't that critical. The pads on the underside of the aluminium plate are just finger-holds that make it easier to reach in and turn the plate at right angles to the slot in the tailcone. The tailcone is somewhat flexible but more than stiff enough to secure the rudder. Van's towbar makes an effective rudder lock, but I find this is quicker and easier to use.

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Ground lug

I make use of Flo-Fast gas cans and hand-crank pump for refueling with unleaded. The pump includes a three-foot grounding cable with a roach clip on the end.

Prior to painting, I could clip the ground clip to the bare metal of the flaperon, but, after painting and adding wheel pants/gear fairings, etc, the only bare metal was the exhaust pipe.

Rather than do the obvious--put a longer grounding cable on the pump--I installed a 1-1/4-inch stainless U-bolt on the bottom of the fuselage below the fuel filler. I included a doubler on the inside where the bolt was installed, and, just to "make it purdier", rather than use regular hex nuts, I used cap nuts on the outside, grinding the top of the cap nuts down such that the bolt can feed through. On the inside, I used the normal hex nuts with star washers to assure conductivity. The lug is ample size for the small Flo-Fast roach clip, and large enough to accommodate a normal size grounding clip for those at airports with unleaded gas pumps.

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Fuel Vent Fairing

I installed the fuel tank vent line modificaiton from Van's, but, having had a bad experience with an insect and a pitot tube left uncovered in the hangar, I was concerned about insect-attracting qualities of the new fuel vent, and the challenge of placing a "REMOVE BEFORE FLIGHT" flag on the underside of the fuselage.

The solution: jdair.com manufactures a fuel vent fairing for RVs, and with a few different parts, it can be adapted to the -12:

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The fairing is designed to fit an AN-4D connector (1/4"), but the vent tube is 3/8" (AN-6D). A 4D-to-6D adapter is used, along with the 6D sleeve and nut used for a flare connection to the 3/8" vent tube. The vent fairing has a screened input tapered to catch the airflow as with the simple tube., and has a small auxilliary vent behind the main vent, along with a third partially drilled hole on the tapered end.

A 10-32 socket head screw is installed 7/8" (on center) behind the original vent hole, which lines up with the rear hole in the fairing and prevents unwanted rotation of the fairing:

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The fairing is attached via the 4D-6D adapter, screwed in from inside the tailcone:

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With the net result:

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Inside the tailcone, the 3/8 tube is trimmed to length, flared and attached with a AN 6D nut and sleeve.

The screen should solve my insect worries, and I suspect that the fairing will increase my airspeed by at least 1 furlong per fortnight--compensating for the 1/2 ounce added weight of the fairing!
 
The fairing from jdair is very nice and I will probably put a set on my -7A, but I went a little simpler on the 12.

I used a pipe cleaner with a "Remove Before Flight" flag for a while but that is not a good long term solution. Having followed Vans plans, I had just a 1/4 inch or so of tubing coming out the bottom of the fuselage.

I took a small piece of screen and secured it over the tube with safety wire. I then put a dab of proseal over the safety wire. It seems to be holding up pretty well. The whole job took about 30 minutes.

The jdair vent would be a nice upgrade if you already had the baggage bulkhead removed.

I've seen first hand how mud daubers can clog a vent and ruin a fuel tank (not my plane) so this is something that I watch for all the time.
 
Nice job Rob of showing all the parts and documenting the improvement. I like it. I think I'll add this to my list of improvements for my next annual.
 
Adding an Aux tank

For all you guys who want more fuel the easiest and cheapest way is to add an aux tank after you are done building. ...

I like the idea but how do you fill the tank? If you remove it to fill, the caps and straps have to come off and an extra set of caps would be needed to keep fuel from spilling and refilling in place seems a guaranteed overflow into the baggaage area sooner or later ...
 
I like the idea but how do you fill the tank? If you remove it to fill, the caps and straps have to come off and an extra set of caps would be needed to keep fuel from spilling and refilling in place seems a guaranteed overflow into the baggaage area sooner or later ...

Well you have to be methodical and have patience. Since you use quick disconnects for the vent and the pick up hoses when removing for fueling chances of spillage is reduced. If you remove it and fill it to the max then you will probably have some leakage around the fill cap. The tank will actually carry 7 gallons but it marked for 6 gallons. So if you only put in 6 gallons and lift it up by the handle on one end to the vertical then gently place it into position while exercising patience lower it back down to the horizontal in the baggage compartment then will probably not spill a drop. Remember you don't have to fill it all the way up, just adding 3 gallons means you can fly approx 4 hours before landing. 3 gallons weights 18lbs, pretty easy to maneuver the aux tank at that weight.
I have my own fuel setup in my hangar so for me filling the aux tank in the baggage compartment is not a problem, but even when using self serve 100LL with a little practice like making sure the nozzle is done dripping and then flip it inverted until over filler neck then rotate it into aux tank usually works fine. Again you only use it when you need it not every time you fly.:rolleyes:;)
 
UHMW tape on nosegear leg fairing

I could post a picture, but it wouldn't show anything...

The faired or un-faired nosegear leg is subject to scraping when removing the lower cowling.

Van's sells transparent TAPE UHMW 3"X10', which I applied to the top side of my painted nose gear fairing...made it slicker than greased snot on a Teflon doorknob, and I no longer worry about scratching up the paint on either the fairing or the cowling.
 
Same concern - -

I have found that a piece of black electrical tape on each side, lightly attached so it comes off easy, works great.
 
Control Stick Pivot Bushings

Made new bushings for control sticks. Fore/aft motion between the two sticks was about ??. Really noticeable when you moved sticks slightly when trimmed in level flight. This was bothering me for a long time. I bought 0.245 x 0.375 brass tubing from McMaster-Carr. Used knurling tool on a lathe to raise the outside diameter. Finished dimensions are now 0.379 OD x 2.030 L which makes a nice slip fit into the control stick. I was going to ream the ID but strangely enough it fit the thru bolt as supplied. Now the pivot point is smooth and there is no relative motion between the control sticks. Added benefit is the slight knurled surface holds grease for lubrication for the pivot.

Love this airplane.... :D

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This radiator baffle is quickly and easily attached or removed by pushing the hinge pins down and out of the hooks.
Blocking the air flow through the upper portion of the radiator keeps the coolant hotter and cabin heat warmer.
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I used similar hooks to prevent the bottom cowl hinge pins from coming out.
Nice, is the piece 100% fabricated or an available part?
 
This mod makes it possible to remove the center instrument panel section without removing then reinstalling the three control cables to the engine. You may or may not anticipate ever modifying that center panel.

Some of us Skyview types have both the original center section (with the GPS cutout) and the new one without it. This mod shows:
a> Make SLOTS extending downward from the engine control cable holes in the new (final) panel piece. The slots cut all the way to the bottom of the panel piece.
b> Cut off the bottom of the OLD center panel piece. It will serve as a backer plate to block those slots.
c> Cut that backer plate so the control cables can be installed flat on the primary panel piece WITH their backing washer, at the top of the slot. Then, the backer plate should be cut to hit that washer and prevent any downward movement of the cable.
d> 2 nutplates, two screws to secure the backer plate.

With great care in the cutting of the slots (dremel and thin cutting disk, thin hacksaw blade), it could be possible to do this by loosening but not removing the cables on an existing installed center panel section.

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This second picture is showing the back side of the backer piece with nutplates attached.

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Assembled. The "hole" looks big because it accomodates the backing washer. But the cable is at the top of the slot in the exact same position as before the hole was slotted.

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Good-day!

Regarding post#163 by Bill H, page 17 of 29.

I have the panel with the GPS cutout (left pic). However, the hole pattern above the throttle is like the one on the right (right pic) with two rows. Is it practical, without removing the panel, to just mark and cut (carefully) across and between those two horizontal rows of holes and achieve the same results? Would the single horizontal row of screws fixing the now lower control panel be strong enough to allow operation of the controls with out the lower panel flexing/bending?
 
I Wouldn't do that. I think you would have too much flex. I think you could, in place, cut the slots to to the control holes using a dremel and also a hacksaw blade.
 
25 gal Fuel Tank Modification

Last year ago I crossed Australia from west to east and back in the RV-12, covering nearly 4,000 miles over a few weeks. The airstrips in our remote outback areas are typically few and far between, so there are often limited options if the weather at a planned destination closes in. Consequently fuel capacity is a significant issue for long-distance flying in much of this country, and the RV-12’s standard 75 litre (19.8 gal) tank is a bit too marginal for comfort at times. On the trip I carried an additional 20 litres (5.3 gal) in a rubber fuel bladder, but had to land somewhere to top up the tank. While this was manageable it was hardly convenient, and having fuel on board that you can’t use when you need it is pretty useless.

Others have previously posted workable solutions for carrying additional fuel in the RV-12. A marine tank in the baggage compartment plumbed into the main tank with a pump and flexible lines to transfer the fuel, or a fuel bladder on top of the tank with gravity feed into the main tank are two options. Neither of these appealed to me much, mainly for safety reasons related to securing the extra tank adequately and the risk of leaks or fumes when transferring fuel around the cabin.

In the end, I decided to increase the capacity of the existing tank from 19.8 gal to 25 gal (95 litres) by simply making it taller. In principle, it’s easy – make a skirt to raise the sides of the tank, take off the tank lid and use it as a template to make a stiff internal brace to go between the top of the original tank and the skirt, put the lid back on, install a new Moeller gauge, and shorten the filler neck and vent line. In practice, it’s quite a lot of work but a fun job if you don’t mind doing a bit of home fabrication. It would be great if Vans offered a taller tank option, but I can well understand why that’s unlikely to happen any time soon.

This is not a trivial modification and there are some issues to think about, the obvious ones being the increased load on the three tank attachment points, a slight aft shift in the c.g. due to the increased tank empty weight, and a significant reduction in baggage capacity with a full fuel load. On the other hand the big advantage is that all the extra fuel is in the tank where you want it – no plumbing, pumps or extra tanks required, and it effectively takes up no additional space.

Why 25 gal and not 30 gal when all that would take is a slightly taller skirt? I was fairly comfortable with 25 gal, but not with 30 gal because of the additional load on the attachment points and c.g. issues. I did enough calculations to satisfy myself that the increased stresses were reasonable using the existing fittings, but if you decide to attempt this, make your own assessment. I also replaced some aft bulkhead attach angle rivets with Cherrymax rivets. For local flying there’s usually no need to fill the tank with more than 20 gals anyway, but it’s nice to have the extra capacity available for longer trips. That extra 70 or so minutes of flying time could be important one day.

Skirt - 85mm high:
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Various parts:
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Internal diaphragm to maintain tank robustness:
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Close up:
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Completed tank:
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Now that is impressive!

Tony

Question, I received the Vans predrilled two piece baggage compartment closeout upgrade. Any reason not to take off the blue protective vinyl if it will be covered? Other than a few places to attach Velcro? Rational, protection or is it a flammable material and must come off....I'm not the builder.
 
Question, I received the Vans predrilled two piece baggage compartment closeout upgrade. Any reason not to take off the blue protective vinyl if it will be covered? Other than a few places to attach Velcro? Rational, protection or is it a flammable material and must come off....I'm not the builder.

Definitely remove the blue vinyl.
 
Definitely remove the blue vinyl.

WILCO All! Thank you!!

Also,

1) I have to drill some of the nutplate and screw holes. Is there a recommended process to follow...as in; do the first and last, cleco them then match drill those in between?

2) Can I use a form of harbor freight clamping device ie a screw clamp, or covered vise grips, or matco brake pad rivet (screw) tool to smash the little nutplate solid rivets rather than go out and buy the proper tool, not sure-other than the nose wheel pant for the nose fork upgrade, and the center flapperon bracket, when I'll need the tool again....

Sorry, sounds dumb I know.

Very Respectfully
Doug/non-builder
 
2) Can I use a form of harbor freight clamping device ie a screw clamp, or covered vise grips, or matco brake pad rivet (screw) tool to smash the little nutplate solid rivets rather than go out and buy the proper tool, not sure-other than the nose wheel pant for the nose fork upgrade, and the center flapperon bracket, when I'll need the tool again....
I would bet you could find someone in your local EAA chapter who would be happy to squeeze a few rivets for you, or loan you a rivet squeezer.
 
Intermittent/Weak Elevator Trim Servo

I bought my RV-12 E-LSA from the original builder two years ago with 48TT. The elevator trim servo seemed weak from the get-go. My point of reference was flying a J3-Cub for 23 years so a correctly operating electrical trim was not my forte.

Long story short? The trim quit working about two months ago and an exhaustive diagnosis didn?t find the problem. The trim began working again and allowed flying until last week when it quit once again. The definitive diagnostic test was to apply voltage from a 9-volt battery to pins 31 & 32 on the 37-pin tunnel M harness D-Sub connector. These pins are the two motor leads for the elevator trim servo. Servo motor ran very strong on 9VDC so servo is good and wiring from pin connector to servo is also good. Problem can only be in the main control circuit board on the instrument panel that houses all the rocker switches and fuses. I suspect bad PWM (pulse width modulator) that directly controls the servo motor speed. Trim pot adjustment for speed didn?t do anything. I have probably spent a total of two weeks troubleshooting this system and finally decided enough is enough.

And so I made a management decision to make my own hard-wired servo control circuit using Ray Allen parts. I have been planning for this day. I basically removed the existing trim up/down rocker switch and in its place I installed a Ray Allen RS2 rocker switch, Ray Allen SPD-1 servo speed control, and a two-position toggle switch which allows either fast or slow servo speed. Wow, what a difference... The servo is now running very strong and the two discrete speeds work really well. Slow speed is used in cruise flight to allow small adjustments to prevent hunting and overshooting. Fast speed is used in the pattern to allow quick setting of trim. Works like a charm. I can pull power, drop flaps in the white arc, and trim for hands-off glide in very short order.

Making this modification is not for the faint of heart. It requires cannibalizing the printed circuit board to allow installing the new rocker switch. The old rocker switch is removed by drilling a succession of small holes through the circuit board that outlines the back of the switch. See attached photo. Then cut through the holes to remove the switch. Foil tracing on the circuit board gets cut in the process but no problem - that circuit is not being reused. Install new Ray Allen rocker switch and speed selector toggle switch through front panel and mount the speed control with double-sided foam tape to the aluminum plate on the back of the control circuit board unit. Use a small rubber grommet to feed wires through the aluminum back panel. As always - use Tefzel wire. You will need to remove pins 31 & 32 from the 37-pin tunnel M harness D-Sub connector and attach to the new Ray Allen hard-wired circuit. It?s also necessary to find a new source of 12 VDC to power this circuit. There is a spare fuse location on the main fuse block. This spare is easily accessible and I soldered a wire onto the base of the fuse spade lug to power the new circuit. A new 2 amp fuse labeled ?TRIM? now powers the new circuit.

Again, this modification is not easy, and once started, it must be completed. There is no going back...


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Most planes have the top of the switch labeled "DOWN", like you have it. I know it seems counter intuitive, but the way that I remember it is that pushing the top of the control stick causes the nose to go down.
 
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