FastTex Posted November 21, 2018 Report Share Posted November 21, 2018 My Mooney M20F has the trim and flap indicators made by a square piece of teflon stuck on top of a metal wire which moves up and down based on the settings. While the trim is working ok the flap indicator keeps ungluing itself leaving the Teflon block loose. I have tried different types of glue (superglue, a softer type, etc). Every few flights I need to open the little window and glue it again! Is there anything different I can do? Is anyone having the same issue? Thanks! Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 21, 2018 Report Share Posted November 21, 2018 FastT, There is no reason for it to be Teflon. That wouldn’t make sense... Teflon is a white, slippery polymer with very low physical strength characteristics... easy to damage with a small amount of force... It would also explain the difficulty found when gluing it to anything... See the better answers below... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
M20F-1968 Posted November 22, 2018 Report Share Posted November 22, 2018 See attached picture. I made new sliders from plexiglass (maybe it was lexan) and imbedded a nut plate between two sheets of the material glued together. The screw captures an eyelet on the end if the cable. No way it can come apart. John Breda Flap&trim-4.bmp Quote Link to comment Share on other sites More sharing options...
M20F-1968 Posted November 22, 2018 Report Share Posted November 22, 2018 See attached picture. I made new sliders from plexiglass (maybe it was lexan) and imbedded a nut plate between two sheets of the material glued together. The screw captures an eyelet on the end if the cable. No way it can come apart. John Breda 1 Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 22, 2018 Report Share Posted November 22, 2018 Ahhh, Now I remember a couple more pics from people with the same challenge... A quick search retrieved a few additional ideas... https://mooneyspace.com/search/?&q=Flap indicators&search_and_or=and&sortby=relevancy Best regards, -a- Quote Link to comment Share on other sites More sharing options...
DualRatedFlyer Posted November 22, 2018 Report Share Posted November 22, 2018 9 minutes ago, M20F-1968 said: See attached picture. I made new sliders from plexiglass (maybe it was lexan) and imbedded a nut plate between two sheets of the material glued together. The screw captures an eyelet on the end if the cable. No way it can come apart. John Breda John, Your skills and handywork never cease to amaze me Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 22, 2018 Report Share Posted November 22, 2018 Lexan/polycarbonate would make a more durable solution... Plexiglass has some issues with being brittle, and sensitivity to UV light and contact with oils... +1 for John’s many additional skills! Best regards, -a- Quote Link to comment Share on other sites More sharing options...
Cyril Gibb Posted November 22, 2018 Report Share Posted November 22, 2018 2 part epoxy worked for me. I used JB Weld quick set applied with a toothpick. Use sparingly. You don't want that stuff where it shouldn't be. There shouldn't be much friction to loosen once glued unless the indicator adjustment is off and you're hitting the limit of the indicator before the flap stops moving. Quote Link to comment Share on other sites More sharing options...
M20F-1968 Posted November 22, 2018 Report Share Posted November 22, 2018 I do not recall the chemicals used, and I think I used Lexan as opposed to plexiglass, however I did not use glues to make the laminated slider ends. I used a chemical that looked and had the consistency of water. It was a solvent and softened the plastic layers and bonded them together when clamped together. I did some homework and found the solvent which was appropriate, then assembled the pasts and clamped them together overnight. A standard nut-plate between the 2 pieces provides the threads for the machine screw. John Breda Quote Link to comment Share on other sites More sharing options...
Bob R Posted November 23, 2018 Report Share Posted November 23, 2018 The flap and time indictors are just made from a white plastic. I had the same issue in my 69 M20E. I went to Walmart and purchased a white cutting board for about $9 and made my own using a scroll saw and some sanding. I drilled the holes (can't remember the exact size) a bit smaller than the wire they sit on. Then I isolated the wire from plastic sources, heated it just a bit with a butane torch, and pushed the new indicators onto the wire. They sit nice and snug now. Someone else told me they used the end of a white wire tie. While I am sure it would work, I am not sure it would look very good. Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 23, 2018 Report Share Posted November 23, 2018 Typical cutting board material... HDPE - high density polyethylene... easy to cut to shape... colored for appearance. Natural color is cloudy milk bottle clear... a good tough material... 1 gallon milk bottles are also HDPE... Solvent bonding... the process of using a solvent to glue polymers together or to something else... Probably enough detail for searching... PP thoughts only... -a- Quote Link to comment Share on other sites More sharing options...
GLJA Posted January 18, 2019 Report Share Posted January 18, 2019 I had my flap indicator wire break at the flap motor end. Going back this weekend to rewire (fish through a new cable) to the indicator. 1- What do I need to be cautious of, when removing the indicator window from the cabin? 2- Anyone know if it's a REALLY tight fit in the conduit or not? Been struggling to find a .058" throttle cable around here. Found a lawnmower place that has some, but it's 3mm thick (.1152" or double the diameter). To me, it'll be better, but it won't work if it won't fit. 3- Just want to remove the belly pan one more time... and get this done. Thanks. Quote Link to comment Share on other sites More sharing options...
N201MKTurbo Posted January 18, 2019 Report Share Posted January 18, 2019 2 hours ago, GLJA said: I had my flap indicator wire break at the flap motor end. Going back this weekend to rewire (fish through a new cable) to the indicator. 1- What do I need to be cautious of, when removing the indicator window from the cabin? 2- Anyone know if it's a REALLY tight fit in the conduit or not? Been struggling to find a .058" throttle cable around here. Found a lawnmower place that has some, but it's 3mm thick (.1152" or double the diameter). To me, it'll be better, but it won't work if it won't fit. 3- Just want to remove the belly pan one more time... and get this done. Thanks. https://www.mcmaster.com/piano-wire Quote Link to comment Share on other sites More sharing options...
MinneMooney Posted February 7, 2019 Report Share Posted February 7, 2019 On 11/22/2018 at 6:28 PM, carusoam said: Typical cutting board material... HDPE - high density polyethylene... easy to cut to shape... colored for appearance. Natural color is cloudy milk bottle clear... a good tough material... 1 gallon milk bottles are also HDPE... Solvent bonding... the process of using a solvent to glue polymers together or to something else... Probably enough detail for searching... PP thoughts only... -a- HDPE typically heat welded. You will not be able to solvent bond, in fact, I don’t know of any adhesives that will bond HDPE, it’s too flexible. Normally you only want to solvent bond when joining 2 pieces of the same material. Lexan and Plexiglass can be solvent welded. Quote Link to comment Share on other sites More sharing options...
carusoam Posted February 7, 2019 Report Share Posted February 7, 2019 The challenges of writing summaries.... Those were two separate subjects in one post... Some polymers are really easy to glue together using solvent bonding... HDPE would require some interesting solvents (less common) to make that happen. PP thoughts only, not a chemist... Best regards, -a- 1 Quote Link to comment Share on other sites More sharing options...
GLJA Posted May 6, 2019 Report Share Posted May 6, 2019 I am in the midst of this same dilemma. My AME suggested using small wheel collars “above and below the indicator” to lock it in place and prevent it from sliding. After thinking about it for a minute. I suggested just using a painted wheel collar as the indicator. We are tackling this tomorrow. I’ll advise how this works out. Quote Link to comment Share on other sites More sharing options...
FastTex Posted May 6, 2019 Author Report Share Posted May 6, 2019 I have solved my issue with superglue. Very carefully clean the metal rod and the Teflon block and even more carefully drop a small quantity of glue on both sides. Push it back and let them vent for a few hours (I waited for several days...) before installing the covering plastic panel. It has been working for months...but now that I made it public I'm sure it will disconnect at the next flight (anti-jinxing move ;-). Quote Link to comment Share on other sites More sharing options...
Hank Posted May 6, 2019 Report Share Posted May 6, 2019 Teflon is difficult to glue . . . . Quote Link to comment Share on other sites More sharing options...
carusoam Posted May 7, 2019 Report Share Posted May 7, 2019 Hopefully, we have confused white HDPE for Teflon.... There is no gluing Teflon...without at least some significant surface pretreatment... Corona treatment or sodium bath? If Teflon was actually used... get ready for plan B... things don’t want to stick to that super slippery surface... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
Hank Posted May 7, 2019 Report Share Posted May 7, 2019 HDPE is also difficult to glue. Isn't that what glue bottles are often made from? At least one version or another of PE, I think. Good luck, let us know what works and how well it lasts. 1 Quote Link to comment Share on other sites More sharing options...
carusoam Posted May 8, 2019 Report Share Posted May 8, 2019 PE is relatively soft and good for squeeze glue bottles... HDPE closely packs the molecules, so they can’t move very much compared to the very chemically similar PE... Chemically, PE and oil are very similar, so water based glue... won’t want to stick to it... We would need a chemist to know the glue attributes better... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
M20F-1968 Posted May 12, 2019 Report Share Posted May 12, 2019 Hopefully, we have confused white HDPE for Teflon.... There is no gluing Teflon...without at least some significant surface pretreatment... Corona treatment or sodium bath? If Teflon was actually used... get ready for plan B... things don’t want to stick to that super slippery surface... Best regards, Teflon can be glued but it has to be etched first. I used to buy teflon sheets that had been etched on one side, and use them on woodwind instrument keys in place of cork. I glued it on with contact cement. John Breda Quote Link to comment Share on other sites More sharing options...
carusoam Posted May 12, 2019 Report Share Posted May 12, 2019 John, If it had a purple-ish brown color to it... etched by sodium. I have a roll of Teflon tape that could be used to hold stuff together in an oven... If the surface was slightly discolored by roughness... typical of corona discharge... Time will have an effect on the strength of surface treatment as well... Many plastics use the Corona discharge treatment to improve surface adhesion for printing/decorating... Treat, and use immediately for Best adhesion... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
Hank Posted May 12, 2019 Report Share Posted May 12, 2019 I once ran a validation study for corona treating a polypropylene part that was immediately coated with a lubricious agent. The typical delay was just a few minutes, and I had to examine several time periods up to 24 hours. The effect fades pretty quickly, then the coating will not adhere to the plastic part. This will vary with different plastics, and with different surface treatments, but I'd not expect corona treatment to last long enough for the item to reach a store, much less for you to find and buy it. It's a pretty short-term effect, but it works well for immediate use. While I know several people who seem to have one of every tool made, I do not know anyone with a plasma oven at home to corona treat their own plastic parts . . . . 1 Quote Link to comment Share on other sites More sharing options...
carusoam Posted May 13, 2019 Report Share Posted May 13, 2019 PP is notorious for surface treatment challenges... Corona is a great addition right on the machine prior to putting ink on it... parts of a second... as some containers/cups run through the machine at 10 cups per second... Prior to the convenience and controllability of Corona... flame treatment was also used... some flame treaters are nice digitally controlled systems as well... Long story, shortened.... running a flame over a plastic surface can oxidize or ionize the surface enough to improve adhesion of glue... without changing the part’s structure or shape... Next up... UV curing of inks... PP thoughts and old memories... -a- Quote Link to comment Share on other sites More sharing options...
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