MB65E Posted October 15, 2019 Report Share Posted October 15, 2019 Anyone play with instrument installations having 1/4” nylaflow instrument lines needing to reduce and Tee to a smaller 1/8” tygon tube with a barbed fitting? I have the need to install an instrument with the small 1/8” pitot static barbs on the back that I don’t want to change. Wishing nylaflow made a Tee fitting with a barb on it. Thoughts? -Matt Quote Link to comment Share on other sites More sharing options...
Mcstealth Posted October 15, 2019 Report Share Posted October 15, 2019 17 hours ago, MB65E said: Anyone play with instrument installations having 1/4” nylaflow instrument lines needing to reduce and Tee to a smaller 1/8” tygon tube with a barbed fitting? I have the need to install an instrument with the small 1/8” pitot static barbs on the back that I don’t want to change. Wishing nylaflow made a Tee fitting with a barb on it. Thoughts? -Matt Well, there is a joke in there if I thought about it long enough but I think I'll just leave it alone. :-) :-) Quote Link to comment Share on other sites More sharing options...
N201MKTurbo Posted October 15, 2019 Report Share Posted October 15, 2019 18 hours ago, MB65E said: Anyone play with instrument installations having 1/4” nylaflow instrument lines needing to reduce and Tee to a smaller 1/8” tygon tube with a barbed fitting? I have the need to install an instrument with the small 1/8” pitot static barbs on the back that I don’t want to change. Wishing nylaflow made a Tee fitting with a barb on it. Thoughts? -Matt You can get Poly Flow fittings that go from 1/4" tubing to 1/8 NPT and 1/8" tubing to 1/8 NPT. Get those two and an 1/8 FNPT to FNPT coupler and hook them together. Just put this inline from a 1/4" tee to your 1/8" device. Quote Link to comment Share on other sites More sharing options...
N201MKTurbo Posted October 15, 2019 Report Share Posted October 15, 2019 (edited) 18 hours ago, MB65E said: Anyone play with instrument installations having 1/4” nylaflow instrument lines needing to reduce and Tee to a smaller 1/8” tygon tube with a barbed fitting? I have the need to install an instrument with the small 1/8” pitot static barbs on the back that I don’t want to change. Wishing nylaflow made a Tee fitting with a barb on it. Thoughts? -Matt That being said, you can't use poly tubing on a hose barb. We need to get you to an 1/8" hose barb. then you can go from hose barb to hose barb with some kind of rubber hose. https://www.mcmaster.com/2838n35 Edited October 15, 2019 by N201MKTurbo Quote Link to comment Share on other sites More sharing options...
MB65E Posted October 16, 2019 Author Report Share Posted October 16, 2019 Thanks! I’ve have the 1/8” tygon tube figured out. I just didn’t know if the nyloflow fittings existed with barbs on them. Guess I’ll need to be creative. So that McMastercarr fitting would work, nyloflow line to a nyloflow tee with a 1/8” NPT tee then nyloflow line to the existing instruments with the 1/8” barb cranked down on the tee to the new instrument!! Just needed to wrap my head around it another way... Are the nyloflow lines nuts normally 1/8”npt thread anyway? I thought they were special. thanks again! -Matt Quote Link to comment Share on other sites More sharing options...
carusoam Posted October 16, 2019 Report Share Posted October 16, 2019 Matt, see if you can get a better rubber hose than Tygon... The plasticized PVC that Tygon uses has been sub-optimal in Mooneys over the decades... There are three failures I can think of... 1) a hose that connects the static system to the altitude hold on an AP unit... the hose fell off and the alt hold didn’t hold... 2) all the wing levers are connected with colored pvc tube that got brittle over the decades... 3) The weirdest of modern Mooney failures... the plasticizer came out of the tube and migrated towards the instruments... the tube was for the back-up vac system in long bodies.... 4) If you are old enough... new cars used to get a film of yuck on the inside of the windows.... the plasticizer in all the vinyl interior used to evaporate and deposit on the glass... more sun exposure, more plasticizer on the windows... It may make the job a bit more complex... but the fittings and tubing you are already using is complex... or use the barb system, and get a better hose... PP thoughts only, not an instrument guru... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
MB65E Posted October 16, 2019 Author Report Share Posted October 16, 2019 Sounds good! I agree with the brittleness, bought 2ft of the fuel line 1/8”id tygon. I’ll see if I like it or not. I’m concerned with trying to keep it simple and not inducing failure points. I don’t get stuck very often! so thank you both for the help. I just didn’t have a tray of fittings to make it work. -Matt 1 Quote Link to comment Share on other sites More sharing options...
Yetti Posted October 16, 2019 Report Share Posted October 16, 2019 Air leak on the bus. dad has the 4 trays of compression brass fittings to replace the blown out plastic push on fitting. Makes life much easier. Fixed to not fail. But there were lots of push on fittings left to fail. Quote Link to comment Share on other sites More sharing options...
MB65E Posted November 4, 2019 Author Report Share Posted November 4, 2019 Thanks all! I took a nylaflow fitting and retapped the end to 1/8-27npt. Along with the 2 fittings from McMaster. Hard to believe no such fitting existed... -Matt Quote Link to comment Share on other sites More sharing options...
N201MKTurbo Posted November 5, 2019 Report Share Posted November 5, 2019 5 hours ago, MB65E said: Thanks all! I took a nylaflow fitting and retapped the end to 1/8-27npt. Along with the 2 fittings from McMaster. Hard to believe no such fitting existed... -Matt As long as it passes a static cert, all is well! Quote Link to comment Share on other sites More sharing options...
A10_Cuba Posted November 3, 2021 Report Share Posted November 3, 2021 Just to refresh this thread I had the same issue although my 1/4” OD polyethylene tubing needs to go into push-lock fittings on the back of two AV-30c’s. the 1/4” poly tubing is tapping off existing 1/4” ID Tygon tubing...arg!! This is the parts list I put together from Spruce. Let you know how it goes! Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 3, 2021 Report Share Posted November 3, 2021 Welcome aboard A10! If you have Tygon in there… There are certainly better choices… for instruments… Better choices for Brittain wing levers too… but when they start leaking, they aren’t as misleading as the instrument failures can be… This post describes failure types of plasticized PVC tubing used in Mooneys… Best regards, -a- On 10/16/2019 at 12:55 AM, carusoam said: Matt, see if you can get a better rubber hose than Tygon... The plasticized PVC that Tygon uses has been sub-optimal in Mooneys over the decades... There are three failures I can think of... 1) a hose that connects the static system to the altitude hold on an AP unit... the hose fell off and the alt hold didn’t hold... 2) all the wing levers are connected with colored pvc tube that got brittle over the decades... 3) The weirdest of modern Mooney failures... the plasticizer came out of the tube and migrated towards the instruments... the tube was for the back-up vac system in long bodies.... 4) If you are old enough... new cars used to get a film of yuck on the inside of the windows.... the plasticizer in all the vinyl interior used to evaporate and deposit on the glass... more sun exposure, more plasticizer on the windows... It may make the job a bit more complex... but the fittings and tubing you are already using is complex... or use the barb system, and get a better hose... PP thoughts only, not an instrument guru... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
MB65E Posted November 3, 2021 Author Report Share Posted November 3, 2021 Hi -A-! I’ve used Tygon for oil and fuel drain lines with no issues. I’ve replaced various clear plastic or nylon lines due to cracking. Is Tygon under the panel that bad? Welcom A10! My install with the adaptors I made worked great right until the FAA issued an AD with the sandia 340A. HA! No fault of my adaptors. As of last week 10/24/21. Dennis from Sandia says they are very close to having a fix for the AD! -Matt Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 3, 2021 Report Share Posted November 3, 2021 1 hour ago, MB65E said: Hi -A-! I’ve used Tygon for oil and fuel drain lines with no issues. I’ve replaced various clear plastic or nylon lines due to cracking. Is Tygon under the panel that bad? Welcom A10! My install with the adaptors I made worked great right until the FAA issued an AD with the sandia 340A. HA! No fault of my adaptors. As of last week 10/24/21. Dennis from Sandia says they are very close to having a fix for the AD! -Matt Hey Matt! Tygon is a good brand of plasticized PVC… Just the problem with the plasticizer… it wants to come out of solution over time and temp… The lines stiffen up as the plasticizer escapes… as they really age… they turn brown, and become brittle… With new tube, they tend to stretch and flow…. Under tension or pressure…. So… if you get a choice PE or PP is probably better… not as flexible, but no plasticizer either… Keep in mind… I’m a polymer guy, not an avionics guy…. For drain lines, without any pressure in them… that don’t get hot… you can’t go wrong… the plasticizer leaking into a waste stream isn’t going to be noticed… Best regards, -a- Quote Link to comment Share on other sites More sharing options...
N201MKTurbo Posted November 3, 2021 Report Share Posted November 3, 2021 You know that Sant Gobain makes thousands of different kinds of tubing made of 100s of different materials. All called Tygon. Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 3, 2021 Report Share Posted November 3, 2021 18 minutes ago, N201MKTurbo said: You know that Sant Gobain makes thousands of different kinds of tubing made of 100s of different materials. All called Tygon. Dang…. I was there before Saint Gobain arrived…. It was called Norton Performance Plastics back then… https://en.wikipedia.org/wiki/Tygon_tubing As Rich so kindly mentioned… the Tygon brand name isn’t enough info to be specific about what tubing material you actually get… Norton was also extruding various types of Teflon materials… Ram extrusion of teflon profiles… to FEP, and PFA, and other super high temp and chemical resistant materials… They even made the skived Teflon tape…. Best regards, -a- 1 1 Quote Link to comment Share on other sites More sharing options...
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