M20C Panel Redo: EGT rotary switch too BIG.

[0TreeLemur]

will do.

[0TreeLemur]

Regarding the panel re-do that started this discussion (see Fig. 1), an issue has emerged having to do with the significant angle from the vertical of the structure to which the M20C instrument panel is mounted.  I estimate it to be 10-11 degrees when the a/c is in level flight, 14 deg. on the ground.  The AH and DG are both designed for installation in a vertically-oriented panel.    Because of the approximately 14-degree bend in the original panel makes the top portion of the panel was approximately vertical.  In the shotgun panel layout, both AH and DG were installed in the top row. Yet, I see that most revised panels folks use in their Mooneys are not bent, rather they seem to be flat plates.  

Both the AH and DG installed in my 20C are supposed to be installed in a vertically-oriented panel.   How have folks solved this problem?   There are compensating shims for individual instruments, but I've not found any yet.   Furthermore, because the DG has setting and bug shafts at the 4:30 and 7:30 positions instead of screws- putting shims in positively will be difficult without shimming the entire instrument.   Is there an "instrument shims R-US" other than a 3-D printer?

Thanks for reading,

-Fred

[N201MKTurbo]

57 minutes ago, Fred_2O said:

Regarding the panel re-do that started this discussion (see Fig. 1), an issue has emerged having to do with the significant angle from the vertical of the structure to which the M20C instrument panel is mounted.  I estimate it to be 10-11 degrees when the a/c is in level flight, 14 deg. on the ground.  The AH and DG are both designed for installation in a vertically-oriented panel.    Because of the approximately 14-degree bend in the original panel makes the top portion of the panel was approximately vertical.  In the shotgun panel layout, both AH and DG were installed in the top row. Yet, I see that most revised panels folks use in their Mooneys are not bent, rather they seem to be flat plates.  

Both the AH and DG installed in my 20C are supposed to be installed in a vertically-oriented panel.   How have folks solved this problem?   There are compensating shims for individual instruments, but I've not found any yet.   Furthermore, because the DG has setting and bug shafts at the 4:30 and 7:30 positions instead of screws- putting shims in positively will be difficult without shimming the entire instrument.   Is there an "instrument shims R-US" other than a 3-D printer?

Thanks for reading,

-Fred

You have two choices, you can make the new panel vertical by adding spacers to the shock mounts or you can have the gyros readjusted to work in the angled panel. I haven't dealt with this for quite a while and the rules are stricter then they used to be so the instrument shops my not have the latitude to adjust the gyros to non-nameplate values anymore. I believe the standard tilt angles are 0 and 8 degrees. If your gyros are 0 degree gyros you may need to get new ones to get the correct tilt. I would just make the panel vertical. Level the airplane per the weighing instructions in the service manual and use a spirit level or a plumb bob to find vertical.  

 

I just looked on line and found the datasheet for a Castelberry AI and it said that it could be adjusted anywhere from 0 to 20 degrees of tilt. So it probably depends on the individual instrument. You should check with an instrument shop. I would figure on few hundred bucks per gyro for a custom tilt adjustment.

Edited February 4, 2018 by N201MKTurbo

[oregon87]

To answer a few questions, the CGR-30P does include red and yellow annunciator lights that will illuminate when any primary function violates a corresponding limit.  If a change to the configuration needs to be made, the display will not have to be returned to do so.  Most of the time, that can be accomplished via e-mail and the CGR's USB port.  Additionally, the CGR is flush mounted and does not overlay the panel.  As an added bonus, we've just launched a rebate!  If interested, have a look at the link below.

buy-ei.com/rebate-2018/

 

[carusoam]

Or click this link to avoid the cut and paste routine...

https://buy-ei.com/rebate-2018/

Best Regards,

-a-

[0TreeLemur]

Back to the original notion of updating the shotgun panel in our '67C, this weekend we start re-assembly.   Here is a photo of the new panel plate incorporating input from this community.  Thanks to everyone who has contributed to the thinking that went into this.  Notice that we bent the panel, and 3-D printed an adapter to compensate for the 13-degree slant of the lower panel and mount the DG horizontally.  There is also a hole for the the JPI-900 warning light directly above the AH.

[carusoam]

Nice work, FRED!

having the JPI's RAD front and center is a whole lot better than a rotary switch!

Best regards,

-a-

[0TreeLemur]

Before.  The thing that bothered me the most is the way the VSI is hiding behind my flyin' hand, and that the EGT selector switch is eating up so much valuable real estate.

[0TreeLemur]

After!  It was a loooong weekend.   Not quite done- need placards.  Anyone have ideas on where to get those?   Does some company sell placards for a '67 M20C?  I have a label maker but don't want to do that if I don't have to...    Big ugly EGT switch gone.  TSO'd EI VA gauge installed above ignition switch.  Waiting on JPI 900 that will go over in place of MP/FP and tach.  Standard six-pack plus backup AHRS.

[Marauder]

47 minutes ago, Fred_2O said:

After!  It was a loooong weekend.   Not quite done- need placards.  Anyone have ideas on where to get those?   Does some company sell placards for a '67 M20C?  I have a label maker but don't want to do that if I don't have to...    Big ugly EGT switch gone.  TSO'd EI VA gauge installed above ignition switch.  Waiting on JPI 900 which will go over in place of MP/FP and tach.  Standard six-pack plus backup AHRS.

Good for you man! You are going to love having the ability to monitor your engine and other functions. And if any of those factory gauges go bad, your 900 will meet the requirements of a primary instrument.

[mike_elliott]

7 hours ago, Fred_2O said:

After!  It was a loooong weekend.   Not quite done- need placards.  Anyone have ideas on where to get those?   Does some company sell placards for a '67 M20C?  I have a label maker but don't want to do that if I don't have to...    Big ugly EGT switch gone.  TSO'd EI VA gauge installed above ignition switch.  Waiting on JPI 900 which will go over in place of MP/FP and tach.  Standard six-pack plus backup AHRS.

Try these guys, Fred. They do a nice job on them and reasonable

Screaming Aero Graphix
Email: Sales@screamingaero.com
Phone: 352-236-6333
Address: 15 SW 10th st Ocala, Fl

[0TreeLemur]

On 2/15/2018 at 5:33 AM, mike_elliott said:

Try these guys, Fred. They do a nice job on them and reasonable

Screaming Aero Graphix
Email: Sales@screamingaero.com
Phone: 352-236-6333
Address: 15 SW 10th st Ocala, Fl

Thanks.  I've contacted them.

We put the ~13-degree factory bend in the panel, and 3-D printed an angled spacer to allow placement of the DG below the AH with it clearing the control column.

[Andy95W]

If you've got the instrument panels out, Fred, you should definitely pay your guy a few extra hours to remove any/all unused wiring, IMO.

[0TreeLemur]

That's the way I'm leaning if it just a few extra hours.   Given that the big bundle that is tucked in between the firewall and vacuum regulator is probably all additional wiring since new, I'm concerned that it might be more than just a few hours.

[Andy95W]

You can probably negotiate something reasonable.  I love ripping out old wiring, but I won't do it if it's inaccessible. With the instrument panels out, I'd take 2-3 hours labor and gladly put in a lot more to do a nice job.  Might depend upon how big a shop it is.

[Stanton R]

On 2/1/2018 at 8:58 PM, Fred_2O said:

After lots of comparing, we have decided to install the JPI EDM-900.  After installing TSO'd Volt/Ammeter, will be able to eliminate cluster gauge, yielding space for Accutrak II if one is available.  Space above the cluster gauge will allow mount of IPad.  Thanks to everyone who provided input and advice.  Much appreciated.  Three week delivery to finish replacing pilot's side panel with six pack.

The EDM 900 has a volt/ammeter that is STC'd for primary replacement.

[Stanton R]

On 2/1/2018 at 8:58 PM, Fred_2O said:

 

Edited March 2, 2018 by Stanton R
duplicate

[0TreeLemur]

I don't know where I read that the 900 wasn't primary for V & A, but looking at the JPI page again, I think you are right.  Thx.

[0TreeLemur]

I dug into this a bit more.  There is conflicting information, because I did read someplace that the EDM V/A is certified primary.   But, looking at the JPI-EDM900 Installation Manual, p. 5, I see that Volts and Amps are _not_ primary.  The Ammeter is the only one required according to the POH for my a/c.  Does anyone know the "authoritative source" to resolve this question?

[carusoam]

The amps reading comes from a voltage reading taken across a known/precise (low ohm) resistor.

The big low ohm resistor is called a shunt.  All Mooneys have one...

JPI would be measuring voltage differences from the source (bus) to ground.  And... across the shunt, displaying the results in amps...

Since it is an easy measurement for JPI, ask them why or why not it is or isn’t a primary display.  Mooneys aren’t the only planes requiring an amp meter.  It’s in the list of tomatoflames or something like that...

PP thoughts only, not a mechanic...

Best regards,

-a-

[ArtVandelay]

Mooneys don’t require an ammeter, the As in tomato flames are for altitude and airspeed. Just because they come standard doesn’t make it required equipment, pretty sure the FAA doesn’t require cigarette lighters for example.

I believe primary is referring to how they are handled, primary have defined limits in the POH (CHTs, OP, etc), secondary don’t have defined limits (OAT, EGT, etc).

 

[0TreeLemur]

On 3/7/2018 at 3:35 PM, teejayevans said:

Mooneys don’t require an ammeter, the As in tomato flames are for altitude and airspeed. Just because they come standard doesn’t make it required equipment, pretty sure the FAA doesn’t require cigarette lighters for example.

I believe primary is referring to how they are handled, primary have defined limits in the POH (CHTs, OP, etc), secondary don’t have defined limits (OAT, EGT, etc).

 

Below is from pg. 5 of the 1967 M20C POH.   It pretty clearly describes how the Ammeter is useful for diagnosing problems with the electrical system.  I'd say that makes it primary, wouldn't you?

[ArtVandelay]

Below is from pg. 5 of the 1967 M20C POH.   It pretty clearly describes how the Ammeter is useful for diagnosing problems with the electrical system.  I'd say that makes it primary, wouldn't you?

Nope, no piston plane has ever crashed because of an ammeter being inop. If the POH didn’t define limits, it’s not a primary.
We have limits defined for CHTs, RPM, oil pressure...

[0TreeLemur]

You are correct, I see no limits.  Thanks for the explanation.  I appreciate the opportunity to learn from you.

[kortopates]

Tomato flames or 91.205 is not the end all list of your aircraft required equipment. In the absence of a KOEL in the POH, you’ll have to consult the required equipment portion of TCDS. You should consult your IA.


Sent from my iPhone using Tapatalk