Bob Cotsford Posted August 13, 2013 Share Posted August 13, 2013 So here's a question for those who like their ARTFs, when the tailplane has to be slid into a closed end slot from the side, how do you make sure that the epoxy is actually filling the joint? I know to mask either side of the joint area, but how do you get the glue into the joint when it's a close fit? Do you just put glue on the tailplane and hope it will carry through? In the past I have tended to avoid epoxy and use PVA and wipe off the excess quickly, or wick cyano in after positioning the tailplane, but on the Wot4 there's not a lot of meat to the tailplane seat so I thought I'd try epoxy as per the instructions. I can see it getting very messy! I'm tempted to cut a chunk out of the rudder post ( as I have done on other models) so that I can slide the tailplane in without smearing glue all over the place, but is there another way? Quote Link to comment Share on other sites More sharing options...
001 Posted August 13, 2013 Share Posted August 13, 2013 Personally I would never use epoxy in that situation, it does not evaporate like white glue, so the weight added in adhesive remains. What I have done is to make an accurate pencil line or use tape where the tailplane has been located to the fuselage line, trim the covering to just inside of that line slide the tailplane in nearly all the way dry, add some white wood glue to the bare wood on the short side, top and bottom so that glue gets dragged into the gap, slide it through 5mm more than necessary add more adhesive to the other side of the joint, slide it back into place, repeating as needed. Until satisfied. Measure. Then wipe the joint clean. Leaving a small smear of glue all along the joint. The glue doesn't dry that fast and the excess can be cleaned off with a damp rag. Measure everything again. If a very small amount of cyano is introduced into the joint after location and before the white glue dries out, it makes an extremely strong assembly. Quote Link to comment Share on other sites More sharing options...
JohnSom Posted August 13, 2013 Share Posted August 13, 2013 On two recent models, a Bixler and a Fun Cub, I have chosen to fix the tailane with a nylon bolt up from the bottom of the fuse into the tail fin. This enables me to dismantle the plane and return it to the original box for storage and transportation. I buy 12" length of M5 nylon threaded rod with nylon nuts on ebay. One nut is 'captured' in the fin and the other fixed with CA glue to the end of the threaded rod to form a bolt aprox 10cm in length. I reckon this method would also avoid the problem with messy glue. Quote Link to comment Share on other sites More sharing options...
Rick Tee Posted August 13, 2013 Share Posted August 13, 2013 I use the same method as Chris above but with epoxy. Epoxy cleans off just fine with surgical spirit. Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted August 13, 2013 Author Share Posted August 13, 2013 CPB, that's what I usually do and it works fine as long as the fit is close. I don't think the amount of epoxy used is should be sufficient to make me worry about the weight. I extended the slot through the rudder post which turned out to be a bit minimalist anyway. It didn't take much epoxy to coat the contact areas and most of what I put on was squeezed out onto the masking tape where I could wipe it off in any case. I was just curious as to how others do this, I can see how first timers get into a bit of a mess with this area. John, my Wot 4 Foam-e uses a bolt on tailplane, and my Stother's designed 60 size Jungmeister uses a bicycle spoke to secure the tailplane in place but to be honest I don't think I'd trust a bolt on tailplane on an IC Wot 4. At least not with me on the sticks. Quote Link to comment Share on other sites More sharing options...
ken anderson. Posted August 13, 2013 Share Posted August 13, 2013 bob-i'm one of the one's that dry fits the tailplane....marks its position with a pen....and then remove's and coats with epoxy--slides it back in and wipe off any that gets out...............done it like this for years and never had a problem.... ken anderson.....ne...1............ slides it back in dept....... Quote Link to comment Share on other sites More sharing options...
Former Member Posted August 13, 2013 Share Posted August 13, 2013 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted August 13, 2013 Author Share Posted August 13, 2013 My epoxy bottles are getting very low since Bob's Models (my local hobby shop) went tits up recently, with the result that I'm trying to stretch out what's left until I need to order something on-line or I can get to a show (Nats?). I was tempted to use outdoor PVA for everything, but in the end so little epoxy is really needed I used the Devcon. I must say the fits are very good so far. Now it's in and braced by the rudder the tailplane seems solid enough but I would have liked to see a cross grain balsa or ply doubler just for confidence. I'm not going silly with the power, just an SC52 2 stroke, so it should be ok. Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted August 14, 2013 Share Posted August 14, 2013 Posted by Bob Cotsford on 13/08/2013 22:18:19: I'm trying to stretch out what's left until I need to order something on-line or I can get to a show (Nats?). LOL! I think we're all in the same boat! I'm looking at the level in my bottle of Deluxe Materials Aliphatic and thinking "will this last until the Nats? I hope so,..." BEB Quote Link to comment Share on other sites More sharing options...
Ausferret Posted August 14, 2013 Share Posted August 14, 2013 Interestingly Andrew Jesky in a video on building and setting up one of his design Slicks tells how he merely CAs the tailplane in and doesn't even bother removing the covering. He has never had an issue with a tailplane moving and I would say he puts his aircraft through more punishing routines than the typical club flyer. I wonder if the old fart ways (I include myself in this category!) are not relevant today? Edited By Ausferret on 14/08/2013 00:51:35 Edited By Ausferret on 14/08/2013 00:55:17 Quote Link to comment Share on other sites More sharing options...
Former Member Posted August 14, 2013 Share Posted August 14, 2013 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
GrahamC Posted August 14, 2013 Share Posted August 14, 2013 IMHO Irvine 46 roughly = SC52. I have Irvine 46 in mine and unlimited vertical. I'm very interested in using Aliphatic to glue in the tailplane. This is the job I hate most with ARTF's and I'm not fond of Epoxy. I always get it everywhere and its not very nice stuff... be interested to hear if others think aliphatic is suitable for this job. {I have another ARTF to asseble for my son!] Interestlingly after two years and a lot of airtime, my epoxied WOT 4 ARTF needed the covering stripped away and some triangle stock added to beef up the join between the fuselage and the horizontal stab. Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted August 14, 2013 Author Share Posted August 14, 2013 Ausferret, it would depend on the structure of your rear-end (ooh missus!). On lots of models that I've built over the years gluing in the tailplane adds to the rigidity of the back end. Two points with cyano onto the film - Not all films give a good bond with cyano - if you get a dribble on the covering some films it will peel off, some it will pull a hole in the film rather than come off. How reliable is the bond between the film and the underlying structure? I also have an OS 46 SFP going idle, I'm mighty tempted to use that with a shorty throttle pipe if I can squeeze the fuel pump into the cowl, that should make the Wotty lift it's skirts and dance quite nicely Edited By Bob Cotsford on 14/08/2013 10:40:42 Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted August 14, 2013 Author Share Posted August 14, 2013 Graham, when I've used PVA the tailplane joint has either outlasted the model or is still going strong. I do tend to add a strip of covering film or a lick of paint to protect the glue from direct contact with exhaust residue, something you don't need to worry about with epoxy. Quote Link to comment Share on other sites More sharing options...
Rick Tee Posted August 14, 2013 Share Posted August 14, 2013 Posted by Percy Verance on 14/08/2013 10:15:45: Irvine .46 in mine Bob, not that I fly it a lot. I prefer the sound and general running characteristics of four strokes. The Irvine seems fine to me, but then I'm one of those who feel you can have too much power....... The old fart ways have never let me down yet Ausferret, so I guess I'll be sticking with them....... Those who choose to use new fangled methods or assemble their artf's while hooked up to an i pod can get on with it for me....... I often ask myself how some of these whizz kids would get on without mixing, servo reversing, expo or dual rates? Edited By Percy Verance on 14/08/2013 10:17:37 Sadly it seems the Irvines are no longer available I agree you can over power an airframe exceeding its flight envelope which may result in unpredictable behaviour, not too mention adding too much weight or over stressing the airframe, 'honest guv i didn't do nuffing, the wings just fell off'. I've seen models setup with 50% EPA!!! and they wonder why servo gears strip, not to mention the loss of resolution. I stick with the old ways too. Quote Link to comment Share on other sites More sharing options...
Ausferret Posted August 14, 2013 Share Posted August 14, 2013 I agree with most in that I remove the covering and glue (usually epoxy) the tailplane in place. However Andrew Jesky is an award winning aerobatic pilot of some standing and I guess his opinion and methods have to count for something. On the quality of the covering on his planes I am guessing they are not of the cheap chinese sticky backed variety. Come to think of it the forces effecting the tailplane (assuming a nice tight fitting mount) would mean a strong adhesive probably is not required. Most of the force would be in the vertical plane and this would bear directly on the airframe. Assuming here of course the tailplane is slid in to a tight fitting slot (as is intimated by having to slide it in and spreading the adhesive). If mounted onto the fus then clearly the joint would be exposed to greater stress. As evidence I have a Parkzone foamy Corsair which has had hundreds of flights and the tailplane is held by two pieces of sticky tape about an inch long on either side and this has never moved, even in two nose in crashes! Edited By Ausferret on 14/08/2013 12:04:53 Edited By Ausferret on 14/08/2013 12:10:52 Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted August 14, 2013 Share Posted August 14, 2013 I would, despite anyone's credentials, beware of this advice. A young girl was killed a few years ago by an out of control WOT4 and if memory serves correctly, it was caused by the builder having glued a tail component in without removing the covering on the glue joint - adhesive unknown...but remember that not all cyano's are equal. Quote Link to comment Share on other sites More sharing options...
Ausferret Posted August 14, 2013 Share Posted August 14, 2013 Got to love the apocryphal internet tales! No definitive reference, the "out of control" aircraft and crash investigation done by whom and using what evidence. Not saying an incident didn't occur but please reference it correctly. Bottom line, my opinion is remove the covering and glue it in with epoxy. Worked for me over the years. Edited for language..... Edited By Pete B - Moderator on 15/08/2013 12:21:04 Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted August 15, 2013 Author Share Posted August 15, 2013 not so apocryphal, that's just the first link Google provided. Sadly it's a true tale, investigated by the police and the BMFA, and if I remember rightly the Coroners verdict confirmed it. Quote Link to comment Share on other sites More sharing options...
IanN Posted August 15, 2013 Share Posted August 15, 2013 Ausferret, fair enough asking for a reference but as you state you are "not saying an incident didn't occur" then your choice of then word "apocryphal - generally taken to mean of dubious authorship or authenticity - is inappropriate The incident occurred as Martin and Bob have stated Quote Link to comment Share on other sites More sharing options...
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