Register

If this is your first visit, please click the Sign Up now button to begin the process of creating your account so you can begin posting on our forums! The Sign Up process will only take up about a minute of two of your time.

Page 1 of 2 12 LastLast
Results 1 to 25 of 31

  1. #1
    Beachy1968's Avatar
    Join Date
    Feb 2014
    Location
    Devon, England
    Posts
    69
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    JetLegend L39 Refurbishment

    I recently acquired a JetLegend L39 in real need of some TLC. As well as being generally in need of some tidying up, the model had a smoke oil fire which caused some damage to the rear fuselage. I therefore intend to carry out a full refurbishment of this model to make her beautiful again and turn her from this...
    Click image for larger version. 

Name:	L39 old scheme.jpg 
Views:	173 
Size:	224.5 KB 
ID:	2025636
    into this...
    Click image for larger version. 

Name:	L39 new scheme.jpg 
Views:	122 
Size:	99.8 KB 
ID:	2025637

    I'm not entirely convinced that anyone will be interested in such a 'build' thread, but for my part I would certainly appreciate any feedback/advice from the many fellow modellers out there who are greatly more experienced than I at this sort of thing. I'm always keen to learn from the real experts.

    Just to say up front, I can't promise to post progress in real time as I'm not quite organised enough to manage that, but I've made a good start and will post chunks as and when I can.

    Thanks

    Mark
    Mark Beacham

  2. #2
    Beachy1968's Avatar
    Join Date
    Feb 2014
    Location
    Devon, England
    Posts
    69
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    OK, so I said I'd made a start so here goes. First step was to total strip the model to a bare airframe, removing all servos, valves, wires and tubes, etc. I could then get on with the messy job of stripping off the old paint.
    Click image for larger version. 

Name:	IMG_1256.jpg 
Views:	153 
Size:	516.1 KB 
ID:	2025648
    Imagine my surprise to find that lurking underneath the black/grey camo scheme was an original factory scheme in blue! The original scheme was painted in the mould so I will leave that and paint over it. Some of the fire damage to the side of the rear fuselage can be seen in the picture above and the damage underneath can be seen in this one below:
    Click image for larger version. 

Name:	IMG_1268.jpg 
Views:	153 
Size:	59.5 KB 
ID:	2025653
    Next I marked out the damaged areas of fuselage which would have to be removed. The heat from the fire has caused distortion of the fibreglass as well as de-lamination of the gel coat in some areas which initially looked OK. As can be seen, despite keeping as much good fuselage as possible the areas to be removed are quite large!
    Click image for larger version. 

Name:	IMG_1269.jpg 
Views:	143 
Size:	97.7 KB 
ID:	2025654Click image for larger version. 

Name:	IMG_1271.jpg 
Views:	146 
Size:	86.7 KB 
ID:	2025655
    No going back now.... This is what a jet looks like when you attack it with a cutting wheel!
    Click image for larger version. 

Name:	IMG_1273.jpg 
Views:	213 
Size:	112.8 KB 
ID:	2025659

    Next...time to make a mould for the repair.
    Mark Beacham

  3. #3
    Edgar Perez's Avatar
    Join Date
    Dec 2001
    Location
    Gurabo, PUERTO RICO (USA)
    Posts
    2,003
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    Interesting. Good luck!
    Edgar Perez
    Puerto Rico

  4. #4

    Join Date
    Dec 2006
    Location
    harwich, UNITED KINGDOM
    Posts
    556
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    I have the exact same colour jet so I would be interested in seeing this to the end
    I just ran out of talent !!!!!!!!

  5. #5

    Join Date
    Jan 2005
    Location
    San Juan, , PUERTO RICO (USA)
    Posts
    935
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    This is a nice thread, as I have one of those in the Slovakian paint
    which I would like to refurbish. The only big problem I have is the second bulkhead
    which is broken. I'm trying to get one. That's the one that holds the front gear.
    But this is going to be interesting.
    hmarmaizmd717

  6. #6
    Beachy1968's Avatar
    Join Date
    Feb 2014
    Location
    Devon, England
    Posts
    69
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    Here are some pictures of the first stage of the repair to the fire damaged fuselage.

    Before the permanent fibreglass repair can be done a mould needs to me made which will be placed over the hole. In order to create a surface from which this mould can be formed I created a temporary 'repair'. The hole was first covered from the back with thin sheet balsa.
    Click image for larger version. 

Name:	IMG_1292.jpg 
Views:	102 
Size:	79.0 KB 
ID:	2026290
    The balsa was then coated with a layer of fine filler up to the level of the fuselage surface.
    Click image for larger version. 

Name:	IMG_1296.jpg 
Views:	101 
Size:	91.8 KB 
ID:	2026291
    The filler was wet sanded until the desired shape was achieved. It is important to achieve as close to perfect a finish as possible as the mould will reproduce any imperfections.
    Click image for larger version. 

Name:	IMG_1301.jpg 
Views:	87 
Size:	80.6 KB 
ID:	2026292
    The damaged area which was removed incorporated a couple of panel line features. To incorporate these in the mould they must be created in the temporary surface. The lines were laid out with chart tape...
    Click image for larger version. 

Name:	IMG_1305.jpg 
Views:	93 
Size:	103.1 KB 
ID:	2026293
    ....and then the filled surface was sprayed with a couple of coats of high build primer.
    Click image for larger version. 

Name:	IMG_1306.jpg 
Views:	87 
Size:	119.8 KB 
ID:	2026294
    The primer was then wet sanded until the chart tape just became visible. The tape was then removed to leave the embedded panel lines. The surface is now ready to lay up the mould.
    Click image for larger version. 

Name:	IMG_1310.jpg 
Views:	94 
Size:	76.6 KB 
ID:	2026295
    I used PVA release agent for this job as I don't need a mirror finish to the mould and PVA is easy to apply and provides a reliable release. This picture shows the surface after it has been treated with the release agent.
    Click image for larger version. 

Name:	IMG_1313.jpg 
Views:	102 
Size:	101.1 KB 
ID:	2026296
    Next, a layer of gel coal was applied and left until it is just tacky.
    Click image for larger version. 

Name:	IMG_1319.jpg 
Views:	94 
Size:	126.2 KB 
ID:	2026297
    Three layers of 160g cloth were then wet laid on top of the gel coat. This was then left to cure for 8 hours.
    Click image for larger version. 

Name:	IMG_1320.jpg 
Views:	89 
Size:	147.0 KB 
ID:	2026298
    This is the finished mould. Before it was removed from the fuselage holes were drilled through to enable the mould to be precisely located.
    Click image for larger version. 

Name:	IMG_1334.jpg 
Views:	118 
Size:	186.8 KB 
ID:	2026299

    Now that I have a mould the permanent repair can be carried out. Pictures of that to follow....


    Last edited by Beachy1968; 08-27-2014 at 12:47 AM.
    Mark Beacham

  7. #7
    Beachy1968's Avatar
    Join Date
    Feb 2014
    Location
    Devon, England
    Posts
    69
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    Having trouble uploading the pictures for post 6 which keep disappearing. Please post if you can't see them!
    Mark Beacham

  8. #8
    Si_B's Avatar
    Join Date
    Aug 2010
    Location
    , , UNITED KINGDOM
    Posts
    84
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    Great thread, keep posting.

    Simon

  9. #9
    Carbon-Customs's Avatar
    Join Date
    Sep 2004
    Location
    Sjaelland, DENMARK
    Posts
    493
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    nice!
    Kasper H
    JetCat P300RX 1:5,5 F-16 - Better to have too much power and not need it, than need it and not have it

  10. #10

    Join Date
    Apr 2008
    Location
    wesley chapel, FL
    Posts
    204
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    Able to see them now. Great work!
    I will fly until they pry the transmitter from my cold dead hands!

  11. #11

    Join Date
    Dec 2003
    Location
    Carolina, PUERTO RICO (USA)
    Posts
    11
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    Mark. How did you strip the model from the old paint?

  12. #12
    Beachy1968's Avatar
    Join Date
    Feb 2014
    Location
    Devon, England
    Posts
    69
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    Hi FELIrc

    I usually use paint stripper that is safe on GRP (it is intended for fibreglass boats), however the type of paint on this model would not come off with this. Luckily, however, I found that it came straight off when wiped with a rag soaked in cellulose paint thinners.
    Mark Beacham

  13. #13
    Beachy1968's Avatar
    Join Date
    Feb 2014
    Location
    Devon, England
    Posts
    69
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    This set of 8 pictures shows how I used the mould I made (see post 6) to carry out the final repair.

    1) The temporary repair that was used to create the mould was removed. As it was only balsa with a very thin skim of filler it pushed out easily.
    2) The mould was attached to the outside firstly using the locating holes drilled before it was first released. Further screws were used to ensure that the edges of the hole are pulled as tightly against the mould as possible.
    3)This shows the gel coat added to the inside of the mould. After this became tacky one layer of 100g and one layer of 160g glass cloth were wet laid on top. As much excess resin as possible was removed to make the repair as light as possible.
    4) After 8 hours the repair was fully cured and the mould was removed to reveal the finished result.
    5) The panel lines have been moulded into the repair. All that was needed to finish was some light sanding around the edges where some resin had crept between the mould and the fuselage.
    6) This shows the finished repair from the inside. The holes left from the screws were filled using a small dab of filler made from resin and microbaloons.
    7) A very light coat of primer was applied to the finished repair to check for any surface imperfections such as pinholes.
    8) The finished repair is as strong as the original structure and adds barely any extra weight. From the outside it will be totally invisible once the model is painted.

    Next the larger hole underneath will be repaired in the same way i.e. a temporary repair is done so a mould can be made and then the mould is used to complete the final fibreglass repair. I'll post pictures of the larger hole repair tomorrow.

    Click image for larger version. 

Name:	IMG_1335.jpg 
Views:	120 
Size:	108.6 KB 
ID:	2026689Click image for larger version. 

Name:	IMG_1338.jpg 
Views:	114 
Size:	143.2 KB 
ID:	2026690Click image for larger version. 

Name:	IMG_1344.jpg 
Views:	118 
Size:	109.5 KB 
ID:	2026691Click image for larger version. 

Name:	IMG_1346.jpg 
Views:	122 
Size:	123.1 KB 
ID:	2026692Click image for larger version. 

Name:	IMG_1350.jpg 
Views:	116 
Size:	131.7 KB 
ID:	2026693Click image for larger version. 

Name:	IMG_1353.jpg 
Views:	113 
Size:	140.7 KB 
ID:	2026698Click image for larger version. 

Name:	IMG_1367.jpg 
Views:	109 
Size:	138.6 KB 
ID:	2026696Click image for larger version. 

Name:	IMG_1370.jpg 
Views:	110 
Size:	106.8 KB 
ID:	2026697
    Last edited by Beachy1968; 08-28-2014 at 01:34 PM.
    Mark Beacham

  14. #14
    Beachy1968's Avatar
    Join Date
    Feb 2014
    Location
    Devon, England
    Posts
    69
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    So here's the final set of pics showing the repair of the fire damage. This set shows the repair of the larger area on the bottom of the fuselage. The process was the same as previously shown so just a brief description for each picture...

    1) Removal of the damaged fibreglass left a big hole!
    2) The hole was blanked off with thin balsa tacked around the edges with CA glue.
    3) Fuselage filled and wet sand to the level of the rest of the fuselage skin. This was much more tricky than the first hole as the fuselage has some double curvature here.
    4) A few coats of high build primer to sort out any minor surface imperfections.
    5) The primer is then sanded back to give the final finish for the mould. The underside has shallower panel lines running through the repair area so I decided to create these in the final paint rather than include them in the mould.
    6) Mould release agent applied to the repair area.
    7) A nice thick gel coat comes next.
    8) The first layer of glass cloth is laid over the gel coat.
    9) A total of 3 layers of 160g cloth was wet laid over the repair area to give a suitably stiff final mould.
    10) This bit's fun. The mould has cured and has been removed and so the temporary surface repair can be broken out to make the hole again! Reminds me of eating an Easter egg!
    11) The finished mould and the hole it will be used to repair.
    12) View from the outside after the repair has been laid up from the inside.
    13) View from the inside of the finished repair. As before one 100g layer and one 160g layer was used to give a total thickness similar to the original material.
    14) The cured repair after the mould has been removed. Again, some minor sanding was required where resin has crept between the mould and the fuselage around the edges.
    15) A very thin coat of primer shows up any minor imperfections which can then be rectified. The fire damage to the fuselage has now been fully repaired.

    Click image for larger version. 

Name:	IMG_1372.jpg 
Views:	67 
Size:	92.7 KB 
ID:	2027841Click image for larger version. 

Name:	IMG_1374.jpg 
Views:	64 
Size:	104.9 KB 
ID:	2027842Click image for larger version. 

Name:	IMG_1376.jpg 
Views:	62 
Size:	80.2 KB 
ID:	2027843Click image for larger version. 

Name:	IMG_1378.jpg 
Views:	68 
Size:	130.0 KB 
ID:	2027845Click image for larger version. 

Name:	IMG_1380.jpg 
Views:	63 
Size:	91.6 KB 
ID:	2027846Click image for larger version. 

Name:	IMG_1382.jpg 
Views:	63 
Size:	114.7 KB 
ID:	2027848Click image for larger version. 

Name:	IMG_1383.jpg 
Views:	61 
Size:	105.5 KB 
ID:	2027849Click image for larger version. 

Name:	IMG_1386.jpg 
Views:	63 
Size:	167.5 KB 
ID:	2027850Click image for larger version. 

Name:	IMG_1389.jpg 
Views:	62 
Size:	123.7 KB 
ID:	2027851Click image for larger version. 

Name:	IMG_1390.jpg 
Views:	67 
Size:	88.4 KB 
ID:	2027852Click image for larger version. 

Name:	IMG_1392.jpg 
Views:	70 
Size:	130.7 KB 
ID:	2027853Click image for larger version. 

Name:	IMG_1395.jpg 
Views:	73 
Size:	95.1 KB 
ID:	2027854Click image for larger version. 

Name:	IMG_1398.jpg 
Views:	72 
Size:	109.5 KB 
ID:	2027855Click image for larger version. 

Name:	IMG_1403.jpg 
Views:	72 
Size:	90.7 KB 
ID:	2027856Click image for larger version. 

Name:	IMG_1405.jpg 
Views:	76 
Size:	116.4 KB 
ID:	2027857

    I shall be away for a couple of weeks now so there will be no more progress until I'm back, then I will start the paint....
    Last edited by Beachy1968; 09-01-2014 at 12:59 PM.
    Mark Beacham

  15. #15
    Beachy1968's Avatar
    Join Date
    Feb 2014
    Location
    Devon, England
    Posts
    69
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    First of all, sorry to anyone who was following this thread for the long gap since my last post. After coming back from my holiday I decided to start another related project - to build a proper spray room. I've been meaning to do this for a while to give me a cleaner and safer environment to paint in. So, after much toil, the dark, dusty, junk filled space that is supposed to be a garage has become this!

    Click image for larger version. 

Name:	Spray room 1.jpg 
Views:	57 
Size:	81.7 KB 
ID:	2050420Click image for larger version. 

Name:	Spray room 2.jpg 
Views:	50 
Size:	85.0 KB 
ID:	2050421Click image for larger version. 

Name:	Spray room 3.jpg 
Views:	55 
Size:	74.2 KB 
ID:	2050422

    I have completed one small job on the L39. The original model had an internal linkage for the rudder, which has been converted to a more conventional external control linkage. The only problem with this is that whoever made the modification decided to insert the servo from below and glue it in so that it could never be removed! Not the best long term solution, so I have created a servo hatch so that the servo can be accessed and removed if needed. I simply marked the required shape and cut a hole with a scalpel. I used fibreglass sheet to create an internal doubler. Just need to drill holes in the corners for the retaining screws.

    Click image for larger version. 

Name:	IMG_1551.jpg 
Views:	68 
Size:	131.4 KB 
ID:	2050426Click image for larger version. 

Name:	IMG_1552.jpg 
Views:	64 
Size:	135.5 KB 
ID:	2050427

    The new paint shop will be put to the test today. Time to shoot some primer....

    Click image for larger version. 

Name:	P1020084.jpg 
Views:	83 
Size:	88.5 KB 
ID:	2050430
    Last edited by Beachy1968; 11-27-2014 at 03:56 AM.
    Mark Beacham

  16. #16
    Beachy1968's Avatar
    Join Date
    Feb 2014
    Location
    Devon, England
    Posts
    69
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    OK, primer done. I have used white primer as this is the correct value shade for the base coat colours I will be using such as yellow, greys and white. Other than that its your usual 4:1 2K product, thinned down a bit as I don't need the high build properties and certainly don't want the resulting weight! Next, a lot of wet sanding.....:-(

    Click image for larger version. 

Name:	P1020098.jpg 
Views:	60 
Size:	103.3 KB 
ID:	2050542Click image for larger version. 

Name:	P1020102.jpg 
Views:	51 
Size:	76.0 KB 
ID:	2050543Click image for larger version. 

Name:	P1020106.jpg 
Views:	49 
Size:	71.6 KB 
ID:	2050544Click image for larger version. 

Name:	P1020120.jpg 
Views:	40 
Size:	76.8 KB 
ID:	2050545
    Mark Beacham

  17. #17
    jcterrettaz's Avatar
    Join Date
    Jul 2007
    Location
    Carp, ON, CANADA
    Posts
    98
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    Tank you for posting , very interesting ...I had similar problem with fire but i take the easy way ......

  18. #18
    757Driver's Avatar
    Join Date
    Oct 2004
    Location
    BA, OK
    Posts
    1,140
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    Great thread! Thank you for the education. I wish more talented guys would share.
    Thanks, Jason
    I love it when my airplane is on fire...as long as the fire stays inside the engine!

  19. #19
    Turbulence's Avatar
    Join Date
    Jan 2002
    Location
    Sahuarita , AZ
    Posts
    1,204
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    Way above my skill level for sure, Great Job. To kind of pair things up, here is a Link to a Composite Wing repair that was done on an a BVM Electra. http://www.rcgroups.com/forums/showt...Electra&page=9 it starts on Post 1081

    Turbulence

  20. #20
    Beachy1968's Avatar
    Join Date
    Feb 2014
    Location
    Devon, England
    Posts
    69
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    I'm glad this is of some interest to someone out there.

    So, after a few busy days I finally got back into the workshop today. Got most of the wet sanding done - so boring! Although I moulded panel lines into the fibreglass repair on the fuselage side I decided that for the larger repair underneath it would be quicker to use the old primer over tape trick to create the panel lines. For those of you not familiar with this it involves laying out panel lines with very thin tape and then applying a coat of high build primer. When the primer is dry you sand the primer back until the tape is exposed and then peel the tape off. This then leaves panel lines in the form of grooves in the primer. I'm not a fan of this technique on a whole plane as it obviously requires quite a thick (and thus heavy) coat of primer, but for small areas like this it works very well. I used 1mm chart tape here, and will hit the area with another coat of primer tomorrow. The lines extend beyond the repaired area to ensure the existing lines are not filled by overspray. Bye for now.

    Click image for larger version. 

Name:	P1020134.JPG 
Views:	46 
Size:	85.0 KB 
ID:	2051906Click image for larger version. 

Name:	P1020139.JPG 
Views:	34 
Size:	84.8 KB 
ID:	2051907Click image for larger version. 

Name:	P1020125.JPG 
Views:	44 
Size:	72.8 KB 
ID:	2051908
    Mark Beacham

  21. #21
    Beachy1968's Avatar
    Join Date
    Feb 2014
    Location
    Devon, England
    Posts
    69
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    Quick update. I've given the repaired area another coat of primer in order to create the missing panel lines. When dry, the primer was then sanded back until the tape showed through. The tape was then carefully removed to leave the embedded lines. Because the moulded panel lines elsewhere on the model are quite shallow I then gave the area a further sand to reduced the depth a bit.
    Nearly time to put the colour on!

    Click image for larger version. 

Name:	P1020152 copy.jpg 
Views:	34 
Size:	109.2 KB 
ID:	2052811Click image for larger version. 

Name:	P1020155 copy.jpg 
Views:	40 
Size:	100.7 KB 
ID:	2052812Click image for larger version. 

Name:	P1020160 copy.jpg 
Views:	39 
Size:	43.7 KB 
ID:	2052813
    Mark Beacham

  22. #22
    757Driver's Avatar
    Join Date
    Oct 2004
    Location
    BA, OK
    Posts
    1,140
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    Very nice!
    Thanks, Jason
    I love it when my airplane is on fire...as long as the fire stays inside the engine!

  23. #23

    Join Date
    Jun 2002
    Location
    Watford, UNITED KINGDOM
    Posts
    7,787
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    Mark

    Ready for Classic Jets?

    Dave
    Motors & Rotors. JetCat, Powerbox, Intairco, Behotec, Graupner. CARF-models Rep. JR Propo for ever!, Jet 1A, MAP, Evojet, BVM

  24. #24

    Join Date
    Jan 2005
    Location
    San Juan, , PUERTO RICO (USA)
    Posts
    935
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    That's a very nice tutorial. Excellent.

    hmarmaizmd717

  25. #25
    Beachy1968's Avatar
    Join Date
    Feb 2014
    Location
    Devon, England
    Posts
    69
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback
    Dave, I've got a couple of days free this week so all being well I should be done for in time for CJ. Never been to Abingdon, so I'm looking forward to it.

    Thanks for the kind words everyone. Hopefully I will have much more of interest to post by the end of the week.
    Mark Beacham


Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
All times are GMT -6. The time now is 04:56 AM.

SEO by vBSEO 3.6.1 ©2011, Crawlability, Inc.