Old Dog needs NEW Info

Taills

New member
I use to build aircraft many many many decades ago, Times have changed, materials are different
I have bought various aircraft over the years, and am looking now to build a little again
My first question to anyone who can help. I am looking at two FT kits the Mini SE5 and the Mini DR1
The biggest question is with new rules these need to be under 250 grams and they are a little over and or
near that limit with the suggested motor and 3S battery. ( power pack )
[ I am also just looking at the plans perhaps to build my own and downsize the entire aircraft to accomplish
my desire ] any advice on that subject ?
SO the questions. To cut weight, can they be flown with a 2S battery and a smaller motor ( I know
they can be ) but what motor and what set up would one suggest to be able to do that and do so
successfully ?
Some newer UMX aircraft have some pretty strong motors and can be flown with 2 or 3S batts, is it possible
to use that style motor/set up in the FT SE5 mini and DR1 Mini kits ?
Thanks in advance
 

Foamforce

Well-known member
Their most recent minis, the Tiny Tutor and the Mini Jenny were both designed to be under 250 with the battery. If you look at their minis, most of them list a weight. Sometimes it’s the dry weight (without battery), but other times it’s the weight with the battery and it says so.


One way to lighten up a plane a lot is to peel off the paper and replace it with packing tape. Do that before you pop the pieces out of the board. Then you can run the tip of an exact knife around the groove to easily trim off the tape. The one annoying part is getting the foam out of the grooves for the folds. Definitely start with one of the planes that were designed to be under 250g first.
 

Piotrsko

Master member
Dont forget also that the power rating of the battery affects it's weight (and the planes flight times) if you can tolerate less powered times, pick the next size down battery. 3 minute feels as good as a 5 minute flight.
 

quorneng

Master member
Designing for 250g tends to be a bit backwards. You cant do anything about the weight of a LiPo and motor so you have to design & build the airframe suitable for the chosen motor and motor down to a specific weight.
In other words you have to be careful with the material you use and how you use them to get a structurally efficient and light airframe. This does require some understanding of the strength of materials and the forces involved.
I have designed and built several sub 250g RC models but all have used thin foam Depron sheet not the standard FT foam board. In most cases the requirement for light weight have made them time consuming to construct.
The one with probably the most impressive performance is this 40"(1020mm) span powered glider.
NewFuseFin.JPG

Built largely of 2 & 3 mm Depron it weighs 219g with an 850mAh 3s on board. Its Blue Wonder 24g motor with a 7x6 prop generates 100W of power giving the plane a power loading of 200W/lb. This gives an "unlimited vertical" type performance yet its aerodynamically efficient airframe means it can "cruise" for an hour at much reduced throttle. The disadvantage common to all lightweight planes is they are seriously thrown about by any turbulence.
Of more conventional appearance is my 242g scale Super Cub.
17JUL20a.JPG

The same 1020mm span and built from 2mm Depron but with more "bulk" and scale features it is rather heavier at 242g despite using a slightly smaller motor driving a 7x4 prop. it uses a 1000mAh 2s LiPo. Obviously it does not have the same full power performance as the above powered glider but it is still quite adequate for its slow speed flight.
To keep below 250g its construction is quite sophisticated. The wings have no spar and the balsa wing struts provide the majority of the strength. To save weight the wheels are made of foam.
You can make quite reasonable planes under 250g but it does take a bit of skill. Like verything the more you do the better you get.
 

Taills

New member
Great information. In my day I built balsa etc and weight was no issue it was balance/power that played
the greatest roles.
These rules of sub 250 g has changed the entire playing field
Why i am seeking as much info as I can get to figure out just what and how I intend to move
forward
I like the mini SE5 and mini DR1 and even the Jenny design, why I asked about motor etc to shave weight
on the first two without changing their airframe much .
I know it can be done, just need to fathom the best way to go about it
I appreciate your reply, information and advice Quorneng
 

Mr NCT

Site Moderator
Great information. In my day I built balsa etc and weight was no issue it was balance/power that played
the greatest roles.
These rules of sub 250 g has changed the entire playing field
Why i am seeking as much info as I can get to figure out just what and how I intend to move
forward
I like the mini SE5 and mini DR1 and even the Jenny design, why I asked about motor etc to shave weight
on the first two without changing their airframe much .
I know it can be done, just need to fathom the best way to go about it
I appreciate your reply, information and advice Quorneng
I'm a huge fan of the DR1. They fly great with an F pack motor and 800mah 2s battery. My lastest (without an attempt to save weight) comes in at 305 g all up. If you leave off the landing gear and strip the paper from the inside of the fuselage you'd probably be under 250.

 

Taills

New member
I'm a huge fan of the DR1. They fly great with an F pack motor and 800mah 2s battery. My lastest (without an attempt to save weight) comes in at 305 g all up. If you leave off the landing gear and strip the paper from the inside of the fuselage you'd probably be under 250.

Excellent video. Great looking aircraft
Thank You or your response and information .
 

Taills

New member
If you're interested in small, light planes of the WWI vintage, and if you're not set on an FT design, I have heard great things about MicroAces.
IMG_4462_grande.jpg
Thank you for your post
I own 9 of their aircraft. They are great as far as their design and control, the only issue is they are so delicate . If flown at all it has to be zero wind as even the slightest breeze tosses them about . Where I live to have a time where no wind is present is few and far between
Why I am looking for something a little larger and heavier , but still around that 250 gram limit .
I own over 40+ aircraft and also several small quads . Most of my planes are larger I do own a SE5a plane but it is large and I own several UMX planes but wanted some WW1 style aircraft in that category. Minimum RC also has a Tigermoth in a smaller format and also a PT17, I have been asking them to create some WW1 vintage style, so far they have acknowledge the request but have not actually done so yet. Even Minimum aircraft are sort of small and struggle in the wind
Thanks again for your suggestion and your response much appreciated.
 

Tench745

Master member
Thank you for your post
I own 9 of their aircraft. They are great as far as their design and control, the only issue is they are so delicate . If flown at all it has to be zero wind as even the slightest breeze tosses them about . Where I live to have a time where no wind is present is few and far between
Why I am looking for something a little larger and heavier , but still around that 250 gram limit .
I own over 40+ aircraft and also several small quads . Most of my planes are larger I do own a SE5a plane but it is large and I own several UMX planes but wanted some WW1 style aircraft in that category. Minimum RC also has a Tigermoth in a smaller format and also a PT17, I have been asking them to create some WW1 vintage style, so far they have acknowledge the request but have not actually done so yet. Even Minimum aircraft are sort of small and struggle in the wind
Thanks again for your suggestion and your response much appreciated.
That's good information, thanks for sharing!

Perhaps one of the Microaces could be scaled up, maybe built with de-papered foam board, and give you the experience you're looking for.
As far as FT designs go, I have an FT mini-scout that weighs in at about 175g with a 2s 600mah battery. It's a fun little plane and capable of flying in (some) wind.
 

Taills

New member
That's good information, thanks for sharing!

Perhaps one of the Microaces could be scaled up, maybe built with de-papered foam board, and give you the experience you're looking for.
As far as FT designs go, I have an FT mini-scout that weighs in at about 175g with a 2s 600mah battery. It's a fun little plane and capable of flying in (some) wind.
I have been considering that concept of Micro aces plane they are very small. I thought about upscaling them a tad and trying it, was not sure how that may come out. Yes I have looked at the mini scout and the mini tutor as well. Still looking for that WW1 style plane is my desire
I have several UMX planes ( Sport Cubs, Champs, Timbers, and Pitts etc )
Thanks for your advice I may have to go that route.
I have boxes of Dollar tree foam board to use.
 

Taills

New member
That's good information, thanks for sharing!

Perhaps one of the Microaces could be scaled up, maybe built with de-papered foam board, and give you the experience you're looking for.
As far as FT designs go, I have an FT mini-scout that weighs in at about 175g with a 2s 600mah battery. It's a fun little plane and capable of flying in (some) wind.
About scaling up the microaces aircraft. The issue I have about that is there are no plans to go by.
the kits come with a book ( directions) and it has several thin ( very thin ) sheets that hold the
pieces you cut out ( tabs ) and then glue together, similar to a model kit almost...LOL
I assume my knowledge of tech to do a scale up is the issue
i see people use something called inkscape or such software
but without a legit plan, I seem to not be able to fathom a process to do so.
Thanks again
 

Tench745

Master member
About scaling up the microaces aircraft. The issue I have about that is there are no plans to go by.
the kits come with a book ( directions) and it has several thin ( very thin ) sheets that hold the
pieces you cut out ( tabs ) and then glue together, similar to a model kit almost...LOL
I assume my knowledge of tech to do a scale up is the issue
i see people use something called inkscape or such software
but without a legit plan, I seem to not be able to fathom a process to do so.
Thanks again
Upscaling a finished plane would be tricky, but it might be possible to put the pieces of an unbuilt kit on a photo-copier and print out an enlarged copy as a template to cut new pieces. Just a thought; it may or may not work.
 

Taills

New member
Upscaling a finished plane would be tricky, but it might be possible to put the pieces of an unbuilt kit on a photo-copier and print out an enlarged copy as a template to cut new pieces. Just a thought; it may or may not work.
I assume it could be done. but again an issue is most ( like me ) do not have a copier that can enlarge
I guess one could try and take it to a UPS or a Staples store to see If that would work
If one could upscale it by scanning and placing it into a software program and then print out several
pages to get the correct size .
The SE5 I have is built so maybe I could use the cut out openings to get the shape and plan that way
i still have several DR1's that i have not built yet and also a Fokker DV II one may scan and try and
upscale.?
Thanks again for the insightful information and advice
I am glad I posted here to pick the brain of others...Lol
 

Taills

New member
Have been watching some videos about the Mini SE5a
I see where many had issues with it flying, many had wing rock and some
could not get it off the ground
Has anyone here had those issues and if yes why did it happen and what
was the fix?
some appeared tail heavy and not correct on CG
as some noted adding weight, but some simply showed video's but no
explanation of the issues
Btw
working on getting some plans to build my own SE5a and DR1
And thanks to all who have replied and gave me advice
I appreciate it very much
 

Taills

New member
theSTOL-er replied
I have a se5 that I built at flite fest. With an 800mah 2s and ft power pack f, it weighs 320g. It flies slow and you NEED to take it off directly into the wind. As with other planes, it does not like high winds. I can't say anything about the dr1, but I think that in almost no wind it will fly great.


Thank you for that information STOL-er much appreciated