Here is a list of all the postings Lindsay Todd has made in our forums. Click on a thread name to jump to the thread.
|Thread: Renaissance by Lindsay Todd|
So time to start some sheeting using 3mm soft balsa trim roughly to shape, I then moisten the outer surface to aid the bend and then glue in place with aliphatic glue and pin in place to sides, formers and stringers. When dry repeat for the other side
The sheeting can also be added to the front including around the cockpit using the same technique using pins and pegs to secure till dry and then repeat for the other side. Make the cockpit slightly oversize so you can trim back more accurately to shape later.
also a good chance to add the 6mm balsa sheeting to the underside front fuselage from U/C plate forward
leave till dry and trim and sand to shape.
more soon. linds
Motor bulkhead former F1 and F2 showing the doubler added in front of F2 at the dowel position and triangular reinforcements to the sides. 6mm square balsa has also been added to the lower fuselage edge
The fuselage sides can now be glued together, at the rear two triangular wedges of 6mm balsa brings the sides together, the top forms the tail plane seat. Clamp till dry.
I use a range of clamps and elastic bands to keep everything together. NB ormer F7 on the bench, I added this once the glue was dry as it just seemed to be easier to locate its position correctly.
Time to add the 6mm square balsa stringers around the upper sections of the formers, these provide support and gluing area for the outer sheeting
NB the position of the 6mm stringer that sits at that is glued onto the top of the 6mm sheet fuselage sides. these are inset to allow the top sheeting to match the outer edge giving a good glue joint.
The rear top section of the fuselage is made up of a central stringer and then an additional 6mm strip cut to width, a razor plane was then used to shape the strip to match the former profiles ready for sheeting
The section just forward of the cockpit has a series of 6mm stringers to create support and gluing area for the top sheeting. NB the 6mm inset strip does not extend into the area that will become the fuel tank / battery hatch
Final jobs before sheeting was to add the 6mm marine ply u/c plate as it offers a bit of protection and also add the triangular strip section around the formers and u/c plate whilst we have access
more soon. Linds
So a backtrack build blog, so were to start well as most people probably know I start these days by getting a set of parts laser cut by Slec (they are used to my drawings by now) and with a build for a magazine when time is a pressure then it does make life a little easier. All the formers are made from either 3mm light ply or marine ply for parts such as the 6mm motor bulkhead and undercarriage block. Wing spars are made from 3mm marine ply and ribs from 3mm balsa. With this design I have deliberately were possible used as many stock commercial materials and sizes as possible so they should be relatively easy to obtain.
As my article hopefully showed and was produced as the model was being built, put the effort in up front and the build can be straightforward enough, laser cut parts are only as good as your drawings so double check the sizes. I had made a basic error with one mid rear former and needed to cut a modified part during the build, mistakes happen but at least it showed the process warts and all.
The build started by cutting two fuselage sides from 6mm medium density balsa and two wing doublers from 3mm medium density balsa (you could use light ply for additional strength but I was happy to go with balsa)
The laminate gets glued onto each fuselage side aligned with the wing cut out. just remember to make a mirror pair!
Whilst that was drying I sited the engine onto the mount and aligned the mount to the 6mm motor mount bulkhead and marked the position of the holes for the mount, throttle arm linkage and a centre clearance hole for the fuel lines. The little slot in the former is not required for I/c engines but the former was designed around originally using electric power so if the is your route then its a useful addition to feed cables through and add some additional cooling airflow. The motor mount was also fitted with captive nuts to secure the motor simply as it is easier at this stage due to limited access later. NB the balsa additions to the base to increase the depth, again a result of choosing to go IC and the mount had to be moved further back so the former needed extending. As the bulkhead gets fully support this is not a problem but I should have really replaced the former with a full marine ply item if I am honest.
Back to the fuselage construction and with the doublers dry each fuselage side can be pinned to the plan and then the top and bottom rear longerons which are made from medium to hard density 6mm square balsa. These can be cut to size and glued in place to the rebates on the fuselage sides. Take care with accuracy as the top longeron assists in setting the rear incidence on the tail plane.
A 6mm balsa plate is glued to the longerons and forms the incidence line for the tail plane so cut and set with care. Vertical braces again from 6mm medium balsa can be cut and glued in position down the rear fuselage sides. When complete repeat the process for the second fuselage side. (I used the first completed side as a template for the second or you could just draw around it to replicate.
Next job is to fit the centre region formers that include the former that sits at the front of the wing that will carry the wing dowels, a ply plate that is effectively a servo tray and the mid wing seat former. These all have tags and slots so the formers key together and are then aligned to the step at the front of the wing cut out and the top edge of the doubler. Just make sure all is square and glue in place to the first fuselage side. NB the servo tray element again is shown here as a solid plate with a circular hole. This locates to the front battery or tank bay support. I later trimmed away a larger hole to site the throttle servo lower down in the fuselage. This may not be necessary depending on the motor you intend to use but worth thinking about as would be obviously easier to cut first and then glue in place. I used a drill and tapered razor saw blade but without such a tool it would be tricky so again plan ahead if you can.
With the first two formers in place we then need to set the position of the motor mount. The plan shows the position based on the motor I used which was an ASP52 Four stroke however if you measure the distance from the motor mount to the prop boss on the motor and add a couple of mmm you can re set this former correctly to the motor you are using and it will not really affect anything other than trimming the fuel tank / battery support plat to a new size before gluing into place. The cut outs on the sides of the tank or battery plate are for loop and hook straps to pass through and around.
more soon. Linds
Edited By Lindsay Todd on 04/06/2018 00:25:04
I have quite deliberately held back on the build blog with the series of design based articles going in the magazine but as the plan will be featured this month its time to back track a little through my build notes and add some further details of the construction for those interested. I'll try and get this done asap. Its been a refreshing project in many ways and the result is a great performing sport model that is pretty straight forward to build. Linds
|Thread: Greenacres MAC Fly Ins 2018|
Unfortunately missed out on this weekends Greenacre's as it is a favourite, I have never really experienced any problems at past events but glad to here the weekend had been successful and will certainly be at the next.
Hi a 2200 3 cell lipo sat directly on a ply tray positioned under the pilot and was sufficient for the model to balance at the plan shown CG for the powered version. For slope (no motor and just a simple hatch) we added some ballast along side the battery to achieve the same position.
hope that helps
HI Guys to answer a few questions raised, re stretching the wing yes section does not change so just two additional ribs could be added or more if you wish of course. RE power set up 400watts would be best for flat field flying as a minimum, always easier to throttle back, if your flying slope then you could probably get away with 300watts as a get home safely sought of option.
Kevin, I would think that power set up should be fine, I tend to go for lower RPM and larger props these days as a bit more efficient with draggy models so 900-1000kv 500 watts would have been a preference on 3-4 cells.
I / we debated covering the fuselage with stringers and fabric but felt the extra weight would penalise and to be honest just liked the open structure as its a bit different.
Hand launching really not a problem, but if concerned just get a mate to give her a chuck.
The motor in the second prototype came straight out of a Parkzone Trojan just for insight
sorry for the delayed response, I'll not bore you with the details but hate computers! Linds
|Thread: Leicester Model Centre Hawk?|
Second model was the LMC Gnatty Sports 60" straight wing, They did a trainer with dihedral and then the Super Gnatty with anhedral. Mine flew with an OS45 as I recall. I actually have a Super Gnatty for restoration in the workshop if I ever get the chance. Loved it great model but was a bit heavy. LMC did a good range as also had the Hawk and the Phantom, they also did a Harrier that looked very challenging when I saw one fly at Woodvale back in the early 1980's. Linds
|Thread: Lockheed Vega|
Hi Nigel from memory about 15-20mm up and down on the elevator, I also use about 50% exponentional (-50% if your a Futaba user like me). Short nose means changes up front can affect the cg position so always best to double check. Have fun. Linds
|Thread: Engine choice for flair puppeteer|
I think we have all called the Puppeteer a Pup, and of course you are quite correct its a bit of a cartoon scale in truth. I actually always thought it was much closer in proportion to the Sopwith Strutter and could be easily adapted with the additional centre strut, moving the cockpit forward and adding the rear gunner as well. Would make a great little project actually if I ever come across a kit. Great flying model on anything from 52 to 70 4stroke. Personally I would go for the 70 size for the bonus useable added weight in the right place. Linds
Good to actually get a bit of model building done, the model is actually just about ready for its maiden but we have had all sorts of issues with internet and phone lines going down due to the building work going on at home of late and just finding 10 minutes seems a huge task in its own right. Builders finish this week so at least we get the house back to ourselves then but of course now its time to decorate. I keep saying to myself it will be worth it in the end. Will update the blog as soon as time allows. Linds
|Thread: Danny's "poor mans Spitty"|
Well done Danny, wish I could have been there. Linds
|Thread: Simon's Skywriter Build|
Lovely Job, Simon, so glad you are happy with her. Linds
Well something I have wanted to do for a while and since larger projects are still having to take a back seat thought I would try and get this one done, I guess the name sort of gives it away. There has been a very successful weight shift design done but I wanted to go for something simpler but retain some character but with sport flying capability so here goes.
As you can see fairly simple layout, span around 57 inches with 300watt power target off 3-4 cell lipo. Lots of progress already so blog will be sort of a catch up. So here is the fuz all built on the bench
|Thread: Harrier Jump Jet- The aeromodelling Holy Grail !!!!|
Very impressive Tony, that's quite an achievement
|Thread: Greenacres 2017|
Given the weather going to come down early Sat morning, thought I'd bring the old Flair Stearman and blow some dust off her for a change and grab a few photos as well. Linds
Hope to travel down late Friday, leave late Saturday as other commitment Sunday, Linds
|Thread: Vintage Cambria Catalogue scans|
I had a Grumman Traveller for years and the CFI was my second model, happy days. My Dad also had a CFI and flew it for years until it became horribly fuel soaked, one afternoon while flying he saw something fall off it, the engine cut and he glided down safely walked over to pick the model up and found that the engine had actually fallen out mid flight hence the engine cut! We found it but I don't recall him fixing it, shame, great flyer.
|Thread: Weston Park 2017|
Well thoroughly enjoyed Weston Park yesterday, never seen the crowds so big and the flight line filled with such variety. Good variety of trade stands and plenty on offer to look at. Some people have said to expensive but I can't help thinking you get what you pay for sometimes and Weston seemed to offer a lot for the money. My wife was with me and thoroughly enjoyed the day too including a wander around the house and gardens which were superb.
a few pics
Roll on Weston 2018!
|Thread: Lindsay Todd's Fred - RCM&E April 2017|
Hi Bertrand, the wing section was simply the scale section from the drawings I had and a straight line drawn from trailing to leading edge to remove the under camber. As simple as that really just to make construction a little easier. It probably does have a reference code or someone will have laid claim to defining its or very similar performance but I have not bothered to track it down or define it as so often in model scales the potential performance figures become a little 'vague' in the real world so I tend to stick with practical evidence and a common sense approach. Linds
Want the latest issue of RCM&E? Use our magazine locator link to find your nearest stockist!