VansAirForceForums  
Home > VansAirForceForums

- POSTING RULES
- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics

  #1  
Old 06-08-2018, 04:16 PM
JDA_BTR JDA_BTR is offline
 
Join Date: Dec 2013
Location: Baton Rouge, LA
Posts: 753
Default Firewall penetration question

With the fm150 should all the cables come through the middle penetration? Or does the governor go through the left? Or?

Do the cylinder and egt temp lines run best thru middle or left? Same question for red cube? My GEA24 is on the left sub-panel
__________________
Ser 104142, RV-14A
N1463
Phase 1 Underway
Urologist, AME
Reply With Quote
  #2  
Old 06-08-2018, 05:03 PM
Mark33's Avatar
Mark33 Mark33 is offline
 
Join Date: May 2010
Location: Baton Rouge, La.
Posts: 639
Default P.M.

I just sent you a P.M.
Reply With Quote
  #3  
Old 06-09-2018, 12:59 AM
JHartline JHartline is offline
 
Join Date: Dec 2012
Location: Carrollton, GA 5GA2
Posts: 206
Default

I routed the control cables as depicted in the plans. Using the mounting bracket from Airflow the cable lengths are correct. See a related thread about how to mount the bracket if you havenít done that part yet.

My GEA24 is on the right subpanel. I split the EGT & CHT into two bundles, motor right and left, and ran them through the openings on their respective sides. I would think thereís plenty of wire length to do it however it works best for you. I believe I ran my fuel flow wire through the left side.
__________________
James Hartline
Carrollton, GA 5GA2
RV-14 - First flight 4/7/2019. Phase I in progress
Reply With Quote
  #4  
Old 11-08-2018, 08:51 PM
JDA_BTR JDA_BTR is offline
 
Join Date: Dec 2013
Location: Baton Rouge, LA
Posts: 753
Default

Iím going to put in another firewall penetration using the Avery kit. I was planning to put it above or below the fuel and oil pressure block and a little left.

Is there a reason not to put a penetration higher on the top part of the firewall or is lower better? Might put it in the space behind where the left top engine mount tubes come together. 14a.
__________________
Ser 104142, RV-14A
N1463
Phase 1 Underway
Urologist, AME
Reply With Quote
  #5  
Old 11-09-2018, 05:22 AM
Tom023 Tom023 is offline
 
Join Date: Jul 2011
Location: Cypress, TX
Posts: 291
Default

I did a combination of the previous responses. I ran control cables as plans and also have the FM150. Split engine left and right and used both pass throughs. I added a 1/2” third pass through below the upper left engine mount specifically for power cables.
__________________
RV14A #140083
AW certificate issued, trying to get to first flight!
2018 Donation+

Last edited by Tom023 : 11-09-2018 at 07:50 AM.
Reply With Quote
  #6  
Old 11-09-2018, 06:41 AM
DanH's Avatar
DanH DanH is offline
 
Join Date: Oct 2005
Location: 08A
Posts: 8,547
Default

May I add a note here?

A tubular steel firewall pass-through filled with an intumescent sealant is very fire resistant. The sealant will also do a pretty good job of locking the components (wires, cables, etc) in relation to each other. However, that fixation is not perfect, as the sealant is elastic. It's also easy to have voids inside the tube, since flow during sealant injection is entirely random.

I've seen a few -14's with power wires, control/instrument wires, and engine push-pull cables all run through the same tube. Must be on the plans that way. This one is typical.

I think it's a bad idea.



First, the fundamental objection; Bowden cables can act like a saw. I've seen 'em cut completely through an Adel clamp. It doesn't take a lot of mis-rigging to have that Bowden pull a little with each startup, for example.

Second, note the approach angle on the big wire. It is hard against the edge of the tube at 1:00 o'clock. It will wear through the insulation there even if the tube is full of sealant.

Third, think about maintenance, or wiring changes in the future. The big control push-pull will wear out eventually. It will need to be removed through the tube, and a new push-pull inserted. If you install the push-pull with its end fittings, then install wires, will you have enough clearance to get it back out without first removing the wires?

Last, clearance issues aside, the sealant plug will need to be cut away from the interior surface of the tube in order to remove wires or cables. To do it requires using a shop-made semicircular "knife" pushed into the tube in two or three places. Here there is no clearance for the approach of the knife. The cables need to come straight out of the fitting for at least an inch or two.

I realize locating firewall passages is a challenge for some builders, so I'm not going to tell you where to put them. If you want to stick with the location(s) on the plans, that's great. However, I strongly recommend that you install separate pass-throughs for control cables and wires. It need not be complicated. Using the above as an example, just put two of them side by side. I'm sure Vans will cheerfully sell you a few more, and they're easy to weld up locally. If you wish, weld multiple tubes on the same baseplate to save real estate.
__________________
Dan Horton
RV-8 SS
Barrett IO-390
Reply With Quote
  #7  
Old 02-03-2019, 03:05 PM
Stockmanreef Stockmanreef is offline
 
Join Date: Nov 2012
Location: Midland, mi
Posts: 713
Default

can some one post a reply with pictures on a good set up for all the fire wall pass throughs and where an extra ones might be placed? It seems like you might want 4. Two for the control cables (one on each side) and two for wires (one on each side).

What is the easiest way to put make a hole through the firewall for the pass through fittings.
__________________
Ken Stockman
Midland, MI
EAA Chapter 1093 member


RV-14a (serial number 140073)
N73XP (at least that # reserved now)
Reply With Quote
  #8  
Old 02-03-2019, 03:19 PM
terrye terrye is offline
 
Join Date: Feb 2010
Location: Vancouver, BC, Canada
Posts: 766
Default

Quote:
Originally Posted by Stockmanreef View Post
What is the easiest way to put make a hole through the firewall for the pass through fittings.
Rotacut high speed steel hole saw backed up with a piece of plywood.
https://www.hougen.com/cutters/sheet...e-cutters.html
__________________
Terry Edwards
RV-9A (Fuselage)
2018/2019 VAF Contribution Sent
Reply With Quote
  #9  
Old 02-03-2019, 04:20 PM
Tom023 Tom023 is offline
 
Join Date: Jul 2011
Location: Cypress, TX
Posts: 291
Default

I made a pilot hole with a carbide drill bit and enlarged with a step drill. Easy peasy.
__________________
RV14A #140083
AW certificate issued, trying to get to first flight!
2018 Donation+
Reply With Quote
  #10  
Old 02-03-2019, 05:47 PM
rv7charlie rv7charlie is online now
 
Join Date: May 2006
Location: Pocahontas MS
Posts: 3,863
Default

Quote:
Originally Posted by Tom023 View Post
I made a pilot hole with a carbide drill bit and enlarged with a step drill. Easy peasy.
Perfect application for those worthless (and almost free) Harbor Freight tools.

For pass-throughs, check the aviation plumbing isle at the local big box store for stainless grab bars. With those, you get a 2fer.
Or,
https://www.ebay.com/itm/2-Pcs-19mm-...53.m1438.l2649

Charlie
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 12:29 PM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.