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 15 12311 ... LastLast
Results 1 to 25 of 369

  1. #1

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    Thorpe F-20 build

    I am scratch building an F-20 Tigershark from plans I purchased years ago from Thorp Brothers out of the UK. The plans are for a 45 size ducted fan. I plan to install a Wren 75 turbine in it. Does anyone have any experience with this jet with a tubine in it that can give me some tips and advise? I can post pictures of the build if there is interest.

    Terry

  2. #2

    Join Date
    Sep 2003
    Location
    Talamanca de JaramaMadrid, SPAIN
    Posts
    328
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    I also purchased the plan pack -with control cables, canopy, instructions and litoplate sample- several years ago, when I was a teenager and still keep it in my plans colection.

    I for sure will follow up your F-20 build thread and wish good luck with your project.

    In the other hand I canΒ΄t help you much as lack experience both building and flying this model. What I have is the review of the fiberglass kit version Ducted Fan powered published in a pair of issues of RC Jet International many years ago. If you think it may be of help, pass me your mail via PM and I will scan and send you a copy of the articles.

    Best Regards


    Jesus Cardin

  3. #3
    Xairflyer's Avatar
    Join Date
    Dec 2002
    Location
    Co. Donegal, IRELAND
    Posts
    2,711
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    I have one that I had being flying with a .45DF, I have looked at it a few time in regard to converting to turbine, but a few things put me off, space for fuel tank (fuse is very narrow only 90mm forward of engine), fitting of retracts, as mine has the foam wing and they are just too thin to practically fit retracts, (used a dolly as a DF) and weight it would be heavy for size.
    I think you could fit a wren44 but dont know about anything bigger.
    Any of the guys that have converted the thorpe F20 to turbine, started with the fibreglass version as far as I know.

    It flys great so no issue there.

    What I would advise and what I have thought about doing a few times is to slightly scale up existing plans, you could get it done easy enough at a stationary store, slightly bigger would be much better in regard to wing loading and obvious space in installing equipment.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Wu60146.jpg 
Views:	72 
Size:	50.5 KB 
ID:	1664633   Click image for larger version. 

Name:	Yt62767.jpg 
Views:	53 
Size:	23.4 KB 
ID:	1664634  
    www.letterkennymodelflyingclub.com
    www.jmaireland.com

  4. #4

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    I will be using Spring Air retracts as they fit just fine. I started to build this several years ago for ducted fan with a Turbax I and OS 46. Now I think a small turbine would be well suited to this project. Space will be an issue. Would like to know what others did. I was thinking of making my own tank and putting it just behind the cockpit in the space between the inlets. Then maybe add two more tanks and put them inside the inlets just ahead of the turbine. Here are a few pics so far.

    Xairflyer- can you give more detail about how the plane flies? Top speed, landing speed, pitch sensitivity, visability in the air, etc. Thanks.

    Terry Jacobs
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Zx70875.jpg 
Views:	112 
Size:	101.7 KB 
ID:	1664661   Click image for larger version. 

Name:	Bw71678.jpg 
Views:	76 
Size:	103.0 KB 
ID:	1664662   Click image for larger version. 

Name:	Fk16622.jpg 
Views:	66 
Size:	92.3 KB 
ID:	1664663   Click image for larger version. 

Name:	Gz75041.jpg 
Views:	67 
Size:	88.9 KB 
ID:	1664664  

  5. #5

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    A few more pics...
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Lj23887.jpg 
Views:	53 
Size:	71.2 KB 
ID:	1664665   Click image for larger version. 

Name:	Ni23090.jpg 
Views:	80 
Size:	100.3 KB 
ID:	1664666   Click image for larger version. 

Name:	Rx60031.jpg 
Views:	57 
Size:	203.7 KB 
ID:	1664667   Click image for larger version. 

Name:	Uo35825.jpg 
Views:	65 
Size:	87.8 KB 
ID:	1664668  

  6. #6

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    and more...
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Ec88109.jpg 
Views:	41 
Size:	69.8 KB 
ID:	1664669   Click image for larger version. 

Name:	Xs59188.jpg 
Views:	49 
Size:	74.1 KB 
ID:	1664670   Click image for larger version. 

Name:	Sx61950.jpg 
Views:	48 
Size:	110.6 KB 
ID:	1664671  

  7. #7

    Join Date
    Sep 2003
    Location
    Omaha, NE
    Posts
    386
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    I had one with a .46 ICDF. I thought it was fast, had a great glide (since my engine always quit) and was fairly hard to see.
    I personally think Wren 75 is way too much power.

    Having said that, I'd like to do another someday with a 90 mm edf.
    Jim

  8. #8
    Xairflyer's Avatar
    Join Date
    Dec 2002
    Location
    Co. Donegal, IRELAND
    Posts
    2,711
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    It is fast in the air but can be slowed down once you master the nose high approach, I never noticed any problems with pitch, but the colour I had did make it tricky to see at times so I have a load of yellow arrows on the bottom.

    The built up wing is probably better to mount retracts, I could'nt do it with the foam wing just too thin.
    www.letterkennymodelflyingclub.com
    www.jmaireland.com

  9. #9
    fireblade5437's Avatar
    Join Date
    Dec 2005
    Location
    Leicester, UNITED KINGDOM
    Posts
    731
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    My friend had one and it was flown with a Wren 44 Gold which had ample power i think the 75 OTT plus being heavier! I am sure Gordon's F20 was fibre glass with foam core wings..

    One thing I remember was we had to increase elevator as we ran out of movement on landing. I will try and find the pics... RIP Gordon

    Alan
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Jh17313.jpg 
Views:	70 
Size:	197.2 KB 
ID:	1664697   Click image for larger version. 

Name:	Vq51711.jpg 
Views:	49 
Size:	66.7 KB 
ID:	1664698   Click image for larger version. 

Name:	Ig11351.jpg 
Views:	40 
Size:	142.3 KB 
ID:	1664699  

  10. #10

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    The reason for the Wren 75 is that I have one already that I can put in it. Why do you guys think it is too much power? It easily fits in the fuse and takes much less space than the Tubax I fan unit and OS 46. Thrust is only about 15 or so pounds. I estimate this model will end up weighing about 10-12 lbs dry with another pound or two for fuel. Doesn't seem overpowered to me. I flew a 17 lbs thrust P70 in a Yellow Starfire that weighed 14 1/2 lbs dry and it flew great. I should have never sold it.

    How fast is this F-20 at top speed? 150 mph? 180 mph? 200 mph? I would like it to go at least 175 mph.

    I am currently flying a 1/8 scale Tam F-16 with the Wren 75 and am use to landing slow and nose high. It is underpowered by the way. Does the F-20 land the same as the F-16? The F-16 will not snap. I don't care how slow you fly. What about the F-20? What speed does it land at? My F-16 lands at about 25-30 mph. Top speed is about 170 mph on a calm, cool day.

    I appreciate the input guys.

    Terry

  11. #11

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    Getting back to the F-20. Started planking the fuse. Also glued second base in place under the nose and started shaping it into place. Here are a few pics of my way to plank. No one ever showed me how to plank, so this is just what I came up with. If someone knows a better way, please tell me.

    I use paper to make a pattern to make sure I get the geometry right. Then I cut the balsa sheet to the pattern with #11 exacto knife. Then spray windex on the side that will not be glued and work it till it softens and bends easily and make sure it fits. Sand here and there for a good fit. Then mix up some 30 minute epoxy and put it in the stringers, bulkheads, and edges where the plank will set against. Try only to put glue on half the plank where another plank will have to be glued later. I don't put any glue on the plank. Then I pin the plank in place and scrap up any excess glue. I use little spring clamps sometimes also. After the glue sets (30 min) I pull the pins and clamps. Any loose spots are glued with quick CA.

    I have ordered a Wren 44 for this plane. Decided against using the Wren 75.

    Terry
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Pn37958.jpg 
Views:	57 
Size:	121.9 KB 
ID:	1700314   Click image for larger version. 

Name:	Sn41776.jpg 
Views:	52 
Size:	126.5 KB 
ID:	1700315   Click image for larger version. 

Name:	Uz67499.jpg 
Views:	55 
Size:	111.5 KB 
ID:	1700316   Click image for larger version. 

Name:	Pj17837.jpg 
Views:	51 
Size:	110.5 KB 
ID:	1700317  

  12. #12

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    Did the nose. Made the middle piece from plywood to have something to shape to. Also will be better to support the model when placed on its nose. Made a paper pattern first from the shape of the nose on the plans. Then cut the plywood out on a scroll saw. Glued 1/2" and 3/4" balsa sheets on with 30 min expoy and sanded the whole thing into rough shape before gluing onto the nose of the model.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Tr49035.jpg 
Views:	34 
Size:	56.3 KB 
ID:	1700838   Click image for larger version. 

Name:	Hc93503.jpg 
Views:	44 
Size:	108.1 KB 
ID:	1700839   Click image for larger version. 

Name:	Uz69276.jpg 
Views:	44 
Size:	153.0 KB 
ID:	1700840   Click image for larger version. 

Name:	Nh11946.jpg 
Views:	38 
Size:	144.3 KB 
ID:	1700841  

  13. #13

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    Then plane and sand...
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Ay73888.jpg 
Views:	23 
Size:	137.2 KB 
ID:	1700853   Click image for larger version. 

Name:	Gb89307.jpg 
Views:	22 
Size:	187.4 KB 
ID:	1700854   Click image for larger version. 

Name:	Ej12758.jpg 
Views:	29 
Size:	43.9 KB 
ID:	1700855  

  14. #14

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    Looks like the nose on the plans to me. Close enough anyway.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Jh17067.jpg 
Views:	27 
Size:	88.4 KB 
ID:	1700857   Click image for larger version. 

Name:	Yt60793.jpg 
Views:	41 
Size:	68.6 KB 
ID:	1700858   Click image for larger version. 

Name:	Sx62978.jpg 
Views:	27 
Size:	48.5 KB 
ID:	1700859  

  15. #15
    Andrew Bird's Avatar
    Join Date
    Jun 2006
    Location
    West Molesey, UNITED KINGDOM
    Posts
    632
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    Nice work!

  16. #16

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    Thanks Andrew. And now for the inlet ducts. This was tedious. Cut several pieces until I got a good fit. Wanted to use 1/64 ply for these but the hobby store had 1/32 so that is what I used. Cut the inlets with the scroll at first but then found it easier to cut them out with siccors. Sprayed them with windex and rolled them up to get them into place. Once a good fit was achieved, I glued them in with medium CA. Then sanded them flush with the bulkheads. Turned out pretty well.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Rp44795.jpg 
Views:	36 
Size:	69.3 KB 
ID:	1700990   Click image for larger version. 

Name:	Rm36726.jpg 
Views:	39 
Size:	63.5 KB 
ID:	1700991   Click image for larger version. 

Name:	Fl18671.jpg 
Views:	42 
Size:	134.8 KB 
ID:	1700992   Click image for larger version. 

Name:	Fz73990.jpg 
Views:	40 
Size:	124.2 KB 
ID:	1700993  

  17. #17

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    More pics of the inlet ducts being put into place and sanded.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Ge95668.jpg 
Views:	54 
Size:	81.2 KB 
ID:	1700999   Click image for larger version. 

Name:	Pk31513.jpg 
Views:	40 
Size:	53.2 KB 
ID:	1701000   Click image for larger version. 

Name:	Ze86584.jpg 
Views:	40 
Size:	75.7 KB 
ID:	1701001   Click image for larger version. 

Name:	Ib82930.jpg 
Views:	40 
Size:	69.0 KB 
ID:	1701002  

  18. #18

    Join Date
    Aug 2002
    Location
    Cincinnati, OH
    Posts
    135
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    Terry,
    It looks great. I love the building thread.
    Glenn

  19. #19

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    Thanks Glenn. I threaded the control cable tubes. Used 36" Sullivan Gold-N-Cable #508. But the ones for the rudder and elevator appear about an inch short. Need to see if I can get a longer set for these. For now I am not going to glue them in place.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Rp43602.jpg 
Views:	40 
Size:	90.1 KB 
ID:	1701974   Click image for larger version. 

Name:	So42723.jpg 
Views:	39 
Size:	64.2 KB 
ID:	1701975   Click image for larger version. 

Name:	Af90354.jpg 
Views:	49 
Size:	67.0 KB 
ID:	1701976   Click image for larger version. 

Name:	Zt52735.jpg 
Views:	60 
Size:	83.5 KB 
ID:	1701977  

  20. #20

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    Vertical stab and rudder were next. Glued together 3/8"x4" balsa sheet with a 1/8"x3/8" spruce piece in the middle. Traced the outline from the plan and cut on a scroll saw. Then capped the leading edge with 1/32 ply and sanded to an airfoil shape per plan.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Rp44694.jpg 
Views:	36 
Size:	72.4 KB 
ID:	1702774   Click image for larger version. 

Name:	Fa86011.jpg 
Views:	35 
Size:	79.6 KB 
ID:	1702775   Click image for larger version. 

Name:	Ua70365.jpg 
Views:	41 
Size:	68.9 KB 
ID:	1702776   Click image for larger version. 

Name:	Mf96750.jpg 
Views:	44 
Size:	71.2 KB 
ID:	1702777  

  21. #21

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    Checked airfoil thickness and compared to plan. Kept sanding till it was right. Took a while but it turned out pretty good.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Tr49493.jpg 
Views:	32 
Size:	58.0 KB 
ID:	1702793   Click image for larger version. 

Name:	Ql33143.jpg 
Views:	36 
Size:	55.0 KB 
ID:	1702794   Click image for larger version. 

Name:	Wc77574.jpg 
Views:	35 
Size:	59.1 KB 
ID:	1702795   Click image for larger version. 

Name:	Ex68839.jpg 
Views:	44 
Size:	51.1 KB 
ID:	1702796  

  22. #22

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    Then cut out and hinged the rudder. I chose the non-scale rudder which is longer. I used Robart hinges and drill guide. Still have to square up the holes so the hinge will recess into the wood. Used a #11 exatco knife and a small file to fine tune the fit. Did not glue the hinges as yet.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Ge96209.jpg 
Views:	24 
Size:	92.1 KB 
ID:	1702797   Click image for larger version. 

Name:	Fa85467.jpg 
Views:	41 
Size:	51.1 KB 
ID:	1702798   Click image for larger version. 

Name:	Ua70612.jpg 
Views:	25 
Size:	58.4 KB 
ID:	1702799  

  23. #23

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    Also put a spruce cap on top and sanded it to shape as shown on the plan. Then glued the vertical stab onto the airframe with 30 minute expoxy making sure to get it as vertical as possible and a good fit with the exhaust tube and spruce stringers.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Ki19047.jpg 
Views:	49 
Size:	52.3 KB 
ID:	1702804   Click image for larger version. 

Name:	Ea84153.jpg 
Views:	35 
Size:	69.3 KB 
ID:	1702805  

  24. #24

    Join Date
    Mar 2005
    Location
    , OH
    Posts
    487
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    Shaped and hinged the elevators the same way.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Tr51604.jpg 
Views:	49 
Size:	89.9 KB 
ID:	1702935  

  25. #25
    Love To build's Avatar
    Join Date
    Feb 2002
    Location
    Edison, NJ
    Posts
    307
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Thorpe F-20 build

    I will follow this thread closely. I purchased this plan and the F104 at a swap meet. I got to find the canopies though. Keep up the good work,
    M4A3, M41, Elefant, Marine M4A3, Building M4A1E8


Page 1 of 15 12311 ... 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 08:04 AM.

SEO by vBSEO 3.6.1 ©2011, Crawlability, Inc.