X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 08 Jul 2009 11:16:04 -0400 Message-ID: X-Original-Return-Path: Received: from smtp-auth-02.mx.pitdc1.expedient.net ([206.210.66.135] verified) by logan.com (CommuniGate Pro SMTP 5.2.14) with ESMTPS id 3748828 for lml@lancaironline.net; Tue, 07 Jul 2009 23:58:48 -0400 Received-SPF: none receiver=logan.com; client-ip=206.210.66.135; envelope-from=rpastusek@htii.com Received: from HTBOB001 (dsl-216-66-233-74.static.linkline.com [216.66.233.74]) by smtp-auth-02.mx.pitdc1.expedient.net (Postfix) with ESMTPSA id 8FFEF8108 for ; Tue, 7 Jul 2009 23:58:13 -0400 (EDT) From: "Robert Pastusek" X-Original-To: "'Lancair Mailing List'" References: In-Reply-To: Subject: RE: [LML] Documentation engine monitoring 4P X-Original-Date: Tue, 7 Jul 2009 23:58:10 -0400 X-Original-Message-ID: <00b201c9ff80$50a46e60$f1ed4b20$@com> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_00B3_01C9FF5E.C992CE60" X-Mailer: Microsoft Office Outlook 12.0 Thread-Index: Acn/ON7rdTTOrsMORUK+S3fDfj3uRgAQW9OQ Content-Language: en-us This is a multipart message in MIME format. ------=_NextPart_000_00B3_01C9FF5E.C992CE60 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Reference Ralph=92s post below,=20 =20 I think you can fill the =93cups=94 of your machined firewall grommets = with silicone very satisfactorily. Use the high temperature red stuff with a = thin nozzle and work it well around the wires inside the grommet =93cup.=94 I = used this technique in several places in my IV-P with all the wires running through a single larger hole in the middle. You might also consider = making you grommets with a =93cup=94 on both sides, and filling both sides with silicone. This is not needed for sealing, but it will help with strain relief of the wires. If you don=92t provide some strain relief, the = wires will break fairly quickly where they pass out of your drilled holes.=20 =20 Consider also how you=92ll repair/replace failed sensors over time=97you = will have to do this=97and how you=92ll disconnect your sensors when you need = to pull the engine=85also a certain thing over time. It=92s possible to = disconnect each sensor and leave it wired to the firewall, but this will be a real pain. Based on good advice from Brent Reagan many years ago, I cut my = connectors to the absolute minimum, but this is one case where a good quality = multi-pin connector may be warranted? =20 In my opinion, the 500 degree fire resistant materials should be = adequate. I=92m pretty sure you=92ll lose the cowling well before the internal = temperature gets to 500 degrees, and local internal =93hot spots=94 at/above 500 = degrees that damage your wiring will cause lots more trouble than losing the sensors.=20 =20 For TSIO-550 powered aircraft, I consider the turbo oil feed and return lines an area worthy of significant attention. A leak/burn/break on any = of these lines will cause instant fire when the oil hits the hot turbos. As = the air/fire is being exhausted through the bottom cowling, the first you = are likely to know about such a fire is when the floorboards start = smoking=85 I installed a =93standard=94 temperature sensor in the cowling exhaust = flow path on each side. They read about 130-140 degrees during normal flight, and = are alarmed at 200 degrees, with the intent that I=92ll recognize this as a = fire and secure the engine before it burns through the floorboards=85 =20 I would strongly recommend you replace the aluminum hard pipe to your = wheel brake cylinders with good quality flex hose. The brake cylinders move a = good bit during use, to include some significant vibration during certain = braking situations. This will quickly fatigue the aluminum line and cause it to fail. You=92ve probably already figured out that without other steering/braking, the MLG brakes are critical to safe operation of your airplane. Lose one brake in flight and a successful landing (defined as = =93the airplane is useable again=94) is in question. If you really want hard = line here, use stainless steel, and include one complete 360 loop to absorb = the vibration and movement. =20 The wiring recommendations are just that; changing the brake line is a foot-stomper. No offense intended! Bob =20 =20 Dear subscribers, =20 I got tiered of looking at how all the wires run through my bulkheads (picture 186). There were even some gaps and I questioned that this = would seal very well. =20 Since I was too cheap to buy the 300$ sealed bulkhead connectors I = decided to make my own (picture 202, 203). I made a sleeve out of aluminum = counted the wires and drilled a hole for each wire/cable with the right size. I = was planning to fill the back side of my bushing with approx =BC=92=92 of = flox to make the plug air tight. I was planning to make the flox really thin that it would flow in nicely and would seal good around my wires. I am concerned = now that the flox might not be flexible enough once it is cured. Are you = aware of any sealer that I could use that is really thin in the beginning and = that would flow in nicely? =20 I also found a lot of wires to the engine monitoring system (picture = 200) being extended in the engine compartment. Is this an area of concern? I = was thinking of buying new sensors with longer cables and run them to the computer box in one piece. =20 What is proper for heat protection for the cables in the engine = compartment. I found products that last to 500 degrees F. Some silicone/fiberglass combinations run up to 700 degrees. Can I go with the 500 degree = products? =20 I do not have any documentation on my engine monitoring system and I = don=92t find anything on the internet. Can anyone give me a file/ copies for the wires installation sketches and set up instructions? =20 I got also done with my brakes now (picture 195). I used aluminum hard = pipe since it is a very similar application which is used in our Cessna. I = also used plasma nitride for rust protection on the rotors and drilled them = to get more surface. =20 Ralf Bronnenmeier ------=_NextPart_000_00B3_01C9FF5E.C992CE60 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Reference = Ralph’s post below,

 

I think you can fill the “cups” of your = machined firewall grommets with silicone very satisfactorily. Use the high = temperature red stuff with a thin nozzle and work it well around the wires inside = the grommet “cup.” I used this technique in several places in my = IV-P with all the wires running through a single larger hole in the middle. You = might also consider making you grommets with a “cup” on both sides, and = filling both sides with silicone. This is not needed for sealing, but it will = help with strain relief of the wires. If you don’t provide some strain = relief, the wires will break fairly quickly where they pass out of your drilled = holes.

 

Consider also how you’ll repair/replace failed = sensors over time—you will have to do this—and how you’ll = disconnect your sensors when you need to pull the engine…also a certain thing = over time. It’s possible to disconnect each sensor and leave it wired = to the firewall, but this will be a real pain. Based on good advice from Brent = Reagan many years ago, I cut my connectors to the absolute minimum, but this is = one case where a good quality multi-pin connector may be = warranted?

 

In my opinion,  the 500 degree fire resistant = materials should be adequate. I’m pretty sure you’ll lose the cowling = well before the internal temperature gets to 500 degrees, and local internal “hot spots” at/above 500 degrees that damage your wiring = will cause lots more trouble than losing the sensors.

 

For TSIO-550 powered aircraft, I consider the turbo oil = feed and return lines an area worthy of significant attention. A leak/burn/break = on any of these lines will cause instant fire when the oil hits the hot turbos. = As the air/fire is being exhausted through the bottom cowling, the first you = are likely to know about such a fire is when the floorboards start = smoking… I installed a “standard” temperature sensor in the cowling = exhaust flow path on each side. They read about 130-140 degrees during normal = flight, and are alarmed at 200 degrees, with the intent that I’ll = recognize this as a fire and secure the engine before it burns through the = floorboards…

 

I would strongly recommend you replace the aluminum hard = pipe to your wheel brake cylinders with good quality flex hose. The brake = cylinders move a good bit during use, to include some significant vibration during certain braking situations. This will quickly fatigue the aluminum line = and cause it to fail. You’ve probably already figured out that without = other steering/braking, the MLG brakes are critical to safe operation of your airplane. Lose one brake in flight and a successful landing (defined as “the airplane is useable again”) is in question. If you = really want hard line here, use stainless steel, and include one complete 360 loop = to absorb the vibration and movement.

 

The wiring recommendations are just that; changing the = brake line is a foot-stomper. No offense intended!


Bob

 

 

Dear subscribers,

 

I got tiered of looking at how all the wires run through my bulkheads = (picture 186). There were even some gaps and I questioned that this would seal = very well.

 

Since I was too cheap to buy the 300$ sealed bulkhead connectors I decided to = make my own (picture 202, 203). I made a sleeve out of aluminum counted the = wires and drilled a hole for each wire/cable with the right size. I was planning = to fill the back side of my bushing with approx =BC’’ of flox to = make the plug air tight. I was planning to make the flox really thin that it = would flow in nicely and would seal good around my wires. I am concerned now that = the flox might not be flexible enough once it is cured. Are you aware of any = sealer that I could use that is really thin in the beginning and that would flow in = nicely?

 

I also found a lot of wires to the engine monitoring system (picture 200) = being extended in the engine compartment. Is this an area of concern? I was = thinking of buying new sensors with longer cables and run them to the computer = box in one piece.

 

What is proper for heat protection for the cables in the engine compartment. = I found products that last to 500 degrees F. Some silicone/fiberglass = combinations run up to 700 degrees. Can I go with the 500 degree = products?

 

I do not have any documentation on my engine monitoring system and I = don’t find anything on the internet. Can anyone give me a file/ copies for the = wires installation sketches and set up instructions?

 

I got also done with my brakes now (picture 195). I used aluminum hard = pipe since it is a very similar application which is used in our Cessna. I also = used plasma nitride for rust protection on the rotors and drilled them to = get more surface.

 

Ralf Bronnenmeier

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