Sam Wragg Posted March 31, 2015 Author Share Posted March 31, 2015 Yes Martyn I reckon this is where most people go wrong, time spent at this stage reflects on the outcome of the finish. When I'm finally satisfied that the surface is as good as possible I seal the surface prior to laying on the glass cloth with a mixture of Finishing resin which consists of:- 15ml Finishing resin 5ml Epoxy thinners (or Acetone) 1 Teaspoon of Micro Balloons I thoroughly give this a good mixing then spread the resin evenly over the surface Some recommend using an old credit card or a piece of stiff card to spread the resin mixture I've found that a piece of 1" wide 1\16 balsa works just as well . This small amount of resin will spread by this this far..... (see image bellow) I know the above image isn't very clear but it shows how far the small amount of resin spreads ( an area of roughly 3"x2" ). The amount of resin mixed was more than enough to cover half of Arrows fuselage. When the resin sets I can then complete the rest of the fuse. Sam Edited By Sam Wragg on 31/03/2015 11:48:17 Quote Link to comment Share on other sites More sharing options...
Sam Wragg Posted April 16, 2015 Author Share Posted April 16, 2015 I was intending to continue with the thread yesterday but felt it was inappropriate after Martyn posted the demise of Concept Right; back to the glassing of Arrow. Once the coat of resin has cured the fuselage is wiped with a cloth soaked in acetone to remove any waxes the resin leaves in its curing and is then given a light sanding to flatten with 220 grade wet & dry (wet) with a finish sanding using a sanding pad (wet) to smooth the curved areas that may have been missed Arrows Fuselage waiting for glass cloth applying I opted to use 24g glass cloth for Arrow, what I did was to make a paper template of the outline of the fuzz allowing for an overlap of the cloth. When the cloth is cut to shape I give the area where the cloth is to be applied a light dusting of Spray Mount Using spray mount helps keep the cloth in position before applying the resin and prevents it from floating on the surface Cloth applied and formed around the curved area waiting for the resin to be applied A mixture of 10ml resin + 1 teaspoon of micro balloons applied. When the resin is 'Green' (semi hard) trim all the excess cloth away, when the resin is cured give the overlap a light sanding then do the same for the other half of the Fuse Completed Fuse awaiting a wash over with Acetone and light sanding. Note removing any surface wax the epoxy resin leaves behind prevents 'Fish Eyes on the surface of the finish' Close up of Arrow after its light sanding. 10ml of resin is then mixed and applied to one side of Arrows fuse and when cured the fuse can be completed Completed Fuselage ready for flatting with a weight gain of 1-1/4oz. Again wiping over the surface with a cloth soaked in acetone prior to sanding Sam Edited By Sam Wragg on 16/04/2015 13:52:05 Quote Link to comment Share on other sites More sharing options...
Martyn K Posted April 16, 2015 Share Posted April 16, 2015 Posted by Sam Wragg on 16/04/2015 13:47:09: I was intending to continue with the thread yesterday but felt it was inappropriate after Martyn posted the demise of Concept Edited By Sam Wragg on 16/04/2015 13:52:05 It will always be an inappropriate time I had never thought about using spray mount. There are 2 types available - permanent and movable - does it matter which is used? When you apply the resin - is that full strength or thinned slightly like when you did the 'primer' coat? This is *really* helpful Thanks Martyn Quote Link to comment Share on other sites More sharing options...
Martyn K Posted April 16, 2015 Share Posted April 16, 2015 Forgot to mention, Halfords also sell those little flat sanding sponges that you mentioned above Quote Link to comment Share on other sites More sharing options...
Sam Wragg Posted April 16, 2015 Author Share Posted April 16, 2015 Martyn, The Spray mount is repositional. I only thin the sealing coat as the acetone allows the resin to be drawn into the balsa before evaporating. I wouldn't advise thinning the resin for subsequent coats as the resin can dry rubbery but by all means use micro balloons as this helps fill the weave. for the final / finishing coat use pure resin Sam Quote Link to comment Share on other sites More sharing options...
Sam Wragg Posted April 21, 2015 Author Share Posted April 21, 2015 Elbow grease required This is where the hard work begins...... RUBBING DOWN !..... I dislike this part but this part dictates the final finish. I usually give the resin about a week or more to fully cure before the final preparation can begin. First of all I once again wipe the surface down with Acetone to remove any surface wax the resin leaves in the curing process. I then brush paint the surface with Etching Primer and leave to harden Over the years I've acquired many tools for the work shop and a Compressor and spray gun(s) is one piece of equipment I'm fortunate to own. This has its advantages as its more cost effective when buying paint. When the Etch Primer has dried, I then spray the surface with white primer/ filler. The two contrasting colours allow you see the low/high areas when rubbing down and also prevents you from going to far and sanding through the cloth. I initially start with 180 grit Wet n Dry (used wet with a dash or two of washing up liquid in the water). I then work my way up to 240 grit until I'm happy. So, basically when all the White primer has been flattened back to the etching primer/cloth the surface is or should be flat enough / defect free to start finally painting. Like I have previously stated this method works for me and I acknowledge that most of you will have developed your own ways of doing things Off to the workshop now to Start with tedious the task of Rubbing Down Sam Edited By Sam Wragg on 21/04/2015 09:34:23 Quote Link to comment Share on other sites More sharing options...
Martyn K Posted April 21, 2015 Share Posted April 21, 2015 Brilliant - I spent months rubbing down the Concept - the only thing I could paint was primer as it was too cold for gloss finishes so I know how you feel. It seems like an endless job, but with the prep and your technique (which I will steal for the next one), it should be easier for you Martyn Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted April 21, 2015 Share Posted April 21, 2015 Why don't you guys give peel ply a go? Saves a huge amount of work. Cheers Danny Quote Link to comment Share on other sites More sharing options...
Sam Wragg Posted April 22, 2015 Author Share Posted April 22, 2015 Always willing to learn new techniques. I've also read about fastening latex sheet in a wooden frame coated with release agent then stretch the latex over one half of the component scrape any air bubbles / exess resin towards the edge and leave to cure. looking at Arrow this morning with fresh eyes she's not as bad as I first though. Because I spent time at the prep stage and used only a small amount of resin the actual finish is pretty good with no fish eyes. It looks rough because I've brush painted on the Etch primer. I rekon a couple of hours flattening and she'll be ready to paint Sam Quote Link to comment Share on other sites More sharing options...
David Oxilia Posted May 11, 2015 Share Posted May 11, 2015 Sam, How's the paint work coming along? Looking forward to seeing her in her colours! David Quote Link to comment Share on other sites More sharing options...
Owdlad Posted July 8, 2015 Share Posted July 8, 2015 Due to technical reasons i have been asked to inform all the followers of this blog that the test flight of Arrow will hopefully happen this evening (weather permitting). If all is well? Sam will transfer all his images of the final installment for me to download ànd is sorry he cannot do this himself I have seen Arrow and couldn't believe it wasn't a composite model until he showed me this blog. He is a bit nervous of the test flight because in his words " in all his years of building its the best one ever" Good luck & hope to be there this eve to watch Owdlad Quote Link to comment Share on other sites More sharing options...
Owdlad Posted July 8, 2015 Share Posted July 8, 2015 Due to technical reasons i have been asked to inform all the followers of this blog that the test flight of Arrow will hopefully happen this evening (weather permitting). If all is well? Sam will transfer all his images of the final installment for me to download ànd is sorry he cannot do this himself I have seen Arrow and couldn't believe it wasn't a composite model until he showed me this blog. He is a bit nervous of the test flight because in his words " in all his years of building its the best one ever" Good luck & hope to be there this eve to watch Owdlad Quote Link to comment Share on other sites More sharing options...
Martyn K Posted July 8, 2015 Share Posted July 8, 2015 Hope the weather is better there than here. Very windy with regular showers. Mind you, you Yorkshire boys do have the Pennines to shelter you from those South Westerly's that batter us hard Lanacastrians Good luck Sam Martyn Quote Link to comment Share on other sites More sharing options...
Owdlad Posted July 8, 2015 Share Posted July 8, 2015 Was rather sceptical at tea time when the call came that the test flight was on. Driving through low cloud and a sudden thunderstorm I was beginning to wonder if Selwyn Froggatt (Sam) new what he was on about when he said it would clear up. Arriving at the field the sun broke through which turned out into a glorious evening with the wind picking up blowing straight down the strip gusting to 25mph. Unperturbed the maestro flew Arrow for the first time without batting an eyelid. The landing was a greaser. Arrow looked Arrow straight in the air and unaffected by the strong wind. To watch Sam put her through her paces on a test flight was something to behold, it was as though he had flown it countless times before. I suppose this was why he was a champion at f3a, also bieng the unassuming chap he is just smiled and said she's a good un let's fill her up again. I take my hat off to him I will post images of Arrow when time permits Owdlad Quote Link to comment Share on other sites More sharing options...
Owdlad Posted July 9, 2015 Share Posted July 9, 2015 Right here we go, Sam left off at the Etch Primer stage. So following Sams notes..... The model was given a light coat of Etch primer and then a top coat of white Primer Filler then the whole fuselage was flattened back. The whole idea off using 2 contrasting colours is so that you can see the where to rub down This is the effect. Laborious but effective in getting a flat surface. When happy once again spray the surface with a light coat of Etch primer then a coat or two of White primer flattened with 600 grade wet n dry Arrow ready for the gloss coat Gloss coat drying off and waiting colours. Quote Link to comment Share on other sites More sharing options...
Owdlad Posted July 9, 2015 Share Posted July 9, 2015 Sam says he makes no apologies about the colour scheme as these are his colours since 1974 (competition colours) and will continue to fly variants of this scheme. Blue 2 tone cockpit Arrow painted with orange faded in Arrow vinyl insignia in position Transfers applied The final image is off Arrow suspended on a brush stale held in a vice while the 2 pack glosss coat is sprayed on 2 coats of 2 pack was sprayed onto Arrows Fuselage the first coat was a very light dusting then after 20 min the second heavier coat was applied. Doing it this way prevents the colours from running into each other and give a nice smooth gloss finish. Sam says because of the toxicity of 2 pack he used a fully enclosed air mask over paper overalls to prevent any skin contact. The Wings and Stab are covered on Oracover (Pro Film) with paint flashes painted on and fuel proofed Owdlad Edited By Owdlad on 09/07/2015 22:17:59 Edited By Owdlad on 09/07/2015 22:22:39 Quote Link to comment Share on other sites More sharing options...
Jack Banner Posted July 9, 2015 Share Posted July 9, 2015 Stunning. Flight video would be awesome. Quote Link to comment Share on other sites More sharing options...
Martyn K Posted July 9, 2015 Share Posted July 9, 2015 I agree. It looks fantastic. Very nice Sam Martyn. Quote Link to comment Share on other sites More sharing options...
Martyn K Posted July 9, 2015 Share Posted July 9, 2015 I agree. It looks fantastic. Very nice Sam Martyn. Quote Link to comment Share on other sites More sharing options...
Owdlad Posted July 10, 2015 Share Posted July 10, 2015 Assembly Images Spring Air Nose Leg (flea bay purchase) **note access holes in bulkhead Because 4 servos in the was used Sam decided the easiest option was to use Mpx connectors for simplicity ** note colour coded shrink wrap** Note Retract Air in valve Blended in wing fairing Sam couldn't resist this shot More to follow Edited By Owdlad on 10/07/2015 08:07:06 Quote Link to comment Share on other sites More sharing options...
extra slim Posted July 10, 2015 Share Posted July 10, 2015 Drool ..........gorgeous Quote Link to comment Share on other sites More sharing options...
Andy Green Posted July 10, 2015 Share Posted July 10, 2015 Lovely build Sam, certainly raised the bar with this one. Andy Quote Link to comment Share on other sites More sharing options...
Martyn K Posted July 10, 2015 Share Posted July 10, 2015 I do like that colour scheme. Looks amazing Martyn Quote Link to comment Share on other sites More sharing options...
ken anderson. Posted July 10, 2015 Share Posted July 10, 2015 thumbs up from me also....1st class workmanship...beats all the ARTF job's any day of the week. ken Anderson...ne...1.......any day of the week dept. Quote Link to comment Share on other sites More sharing options...
Steve Dunning Posted July 10, 2015 Share Posted July 10, 2015 What can I say Sam. A fantastic job showing what can be done with care, a little elbow grease and attention to detail. That lead to a to a non-eventful initial flight that proves that all the prep done in the workshop gives a model that is 95% there when taken to the flying field. A couple of Supra Fly 45's have recently had their maiden flights and their owners called them 'boring' because of the lack of any trimming required. The flights did leave them with a big smile on their faces though as I imagined you had Sam after the initial flights with the Arrow. Look forward to seeing it 'in the flesh'. Steve Quote Link to comment Share on other sites More sharing options...
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