help with hi boy precedent rebuild

[snakeyme 0]

Long time no speak all.

I'm having to rebuild my hi boy precedent because a removals company destroyed the plane during a house move, I'm planning on building it out of balsa instead of ply except for the firewall and a few other small pieces.

Trouble is that as I only have the tail section left in 1 piece I don't have a bases to go on, so I'm wondering if anyone has or know where I can get some build plans for it.

I'm also planning on making the fuselage longer (details are below) and possibly slightly wider and I'm wondering if there would be any complications in doing so;

The original details are:

Length is 44" and wingspan is 62"

And I'm thinking of doing the fuselage to 50" long and also an inch wider.

If anyone could advise on this, it would be great thanks

Dan

[Trevor 25]

Hi, I would have thought it would be easier and cheaper to buy a new trainer. The HiBoy is not the easiest plane to learn on and a major rebuild with covering and wood costs could cost as much as a new trainer.

Failing that, the HiBoy is an old model so I would be surprised if any plans exist. Have you searched the net for any?

[snakeyme 0]

Yep I have looked for plans online but havnt found anything unfortunately.

The rebuild is more for experience than anything as I have my eyes on a set of plans for a 134" wingspan lancaster and a 72" wingspan spitfire (the lancaster will eventually be electric) and to buy everything needed to build those 2 planes would a waste of money as I don't currently have the experience to build the spit and lancaster, the hi boy being a trainers is a fairly simple construction due to the fact of it being a trainer and as such, I thought it will be a good place to start my experience.

[arun 0]

Quote

I'm planning on building it out of balsa instead of ply except for the firewall and a few other small pieces

Make sure you replace ply with ply. It has significantly different properties and is used by designers for good reason. Plenty of books out there on model aircraft design if you want to know more.

Quote

I'm wondering if anyone has or know where I can get some build plans for it.

What is left of the Precedent range is stocked by SLEC so try them. I wouldn't hold much hope for that particular model...

Quote

I'm also planning on making the fuselage longer

Don't. Trainers follow a very constant set of design ratios and unless you really know what you are doing (i.e. don't need to ask ) I wouldn't recommend this change as all the parameters of an aircraft are interrelated so changing this will have other effects which without seeing exactly how you plan to lengthen/widen would be difficult to quantify. If you actually mean you want to scale everything up a bit, then fine... but you'll need a new plan, probably engine and it's a whole new build.

Quote

a set of plans for a 134" wingspan lancaster and a 72" wingspan spitfire

I always think people should have a stretch-goal to aim for ... good on you. But take it in baby steps as both those models are non-trivial and probably something you might approach with many hundreds of flying and building hours safely under your belt having flown and built a wide variety of models up to that point.

[snakeyme 0]

Thanks for info with regards to resizing, the basic idea for lengthening the fuselage is the fact that the main body is made out of 3mm heavy ply and I was gunna use ply box supports down the length but use 3mm balsa sheet to skin the aircraft, being lighter, I thought it'll be safe to extend the length by 6" and width by 1" to equal the overall weight of the original fuselage.

As for having a dream to reach as is the case of the lancaster and the spitfire and doing it in steps, well my plan is to start of simple and progressively increase the skill level and size if the aircraft aswell.

The basic idea is as follows;

Start with a 40 sized trainer,

Then try to scale up a trainer build by using the j3 cub as a platform,

Then move to either bi-plane or a mid/low wing aircraft. And while doing this, start to include more detailing as I progress.

I hope all of that makes sence.

[arun 0]

snakeyme said:

I thought it'll be safe to extend the length by 6" and width by 1" to equal the overall weight of the original fuselage.

It's not just about matching weight, otherwise I'd be able to make a brick of the same weight fly It's about aerodynamics...

Have you tried looking on the BMFA classifieds website, people often sell old but complete kits there. Maybe there are some near you that you could buy for a few quid if you want to gain experience - it would be more productive that trying to build blind without plans...

[snakeyme 0]

Thanx, I didn't think of that (bmfa), ill look into it

[Martin 0]

It seems unlikely that you'll be able to find plans for that particular trainer, especially since I think it was sold as a kit with foam wings. However, if you want to try building from plans there are plenty of trainer designs out there.

A few minutes of web searching turned up this list (from 2010) of lots of kits and plans available, with comments about each one: http://www.modelflying.co.uk/news/artic ... iner/6101/

Don't forget that it can be surprisingly expensive to build from plans - all the little bits of hardware soon mount up, along with the tools and equipment if you don't have them already. With ARTF trainers around the £60 mark, you may find that building from plans works out more expensive. If you're treating this as a learning experience to learn about building, though, then it does make sense.

As Arun points out, don't go changing the specified materials (e.g. using balsa instead of ply). Ply is heavier and more expensive than balsa, so a designer will only specify it if there is a very good reason to do so. Similarly, changing the lengths of parts of the plane has the potential to drastically change the flight characteristics, so definitely goes into the category of something to only do if you know what you're doing.

Martin

[snakeyme 0]

Thanks martin, I've just had a look at the list and there's a few that I'm gunna look into.

These are:

73" span piper cub

63" eagle 2

2.4m precedent t240

2.4m senior telemaster.

I'm thinking more about the t240 atm as I have a .61 2-stroke that will fit it nicely.

Any thoughts on that guys.

Or does anyone have any plans I can either borrow a copy of or buy off them of a decent trainer please.

[arun 0]

Others may disagree, but I don't see point of building trainers from plan. When you build from plan or even kit you invest a lot of time and effort into something that has a very low life expectancy. Buy ARTF when learning, when you are at a point of not damaging airframes, build from plans or kits. Maybe this is a materialistic/un-romantic way to look at the hobby but I think it gives the learner the best chance of success.

[snakeyme 0]

Thanx arun, I don't know what to do as I just want something that's easy to build and fly, its about more than the price tbh.

Its more experience related and the fact that I have a second baby on the way (due in october) and I need something to keep me relaxed and busy so I can support the family in a better mentality than if I had nothing.

If that makes sence

[arun 0]

It makes perfect sense. But as a father of a 3yr old and a 1yr old I can assure you that you will not have time to even build an ARTF!! Instead you'll have to make do with typing on forums and wishing you had more time to fly

[snakeyme 0]

My son will irronically be 2 in october and I do know the feeling, that's why I'm seriously considering getting a phoenix and tx combo deal (spektrum dx6i, 2 rx's, full phoenix program and the lead to go with it) all for 160 quid, so I can have fun on the sim for the time I don't have to build (also my son can try it) and when I get the slightest bit of time (when my other half goes to her mums for the weekend with the kids), I can build the planes well atleast that's the plan.

[arun 0]

Now you're talking... sim is the way forward in this hobby and Phoenix is the best low cost entry.

[snakeyme 0]

I've used phoenix sim before while I was at a shop and the things I can do on it is unreal, I can actually do a prop hang with an extra 500 and maybe when I have it, I can fly with you guys in a group session

[snakeyme 0]

Hey guys, I just found a load of brilliant plans online for free, here's the list;

B17f

Cessna 170

P51d

Inspirer mb 10

Jackdaw frog 60"

Navajo

Consolidated pby 5

Piper cub

Super 60 by colin usher

Telemaster olympic 70"

Trainer MEN 58"

Trainermaster

Kadet

Spitfire

Skywalker

 

And all of those for free

 

So all, which plans do u like the sounds of

[Peter Royall 47]

The Hi boy was never supplied with plans, just drawings of how it went together.

Also there was a Mk1 and a Mk2 design. The mk1 was chunkier in the fuselage, the mainwing being more or less the same with the two designs.

And I just sold a 3 channel kit on ebay for £25. Quite easy to convert to 4 channel if you know how.

 

I have just made one in the original light ply, having come into possession of a used wing, and modified the tailfeathers from a Gangster 60.

I thought it would be a good model to start training for one of my Grandsons.

 

Luckily, I can probably help with the part patterns for the fuselage, there might be a problem with the wing, they were all veneered foam, but i have seen built up wings over the years, that people have made from scratch. Just the wing chord is needed to cut out some ribs, and use a bit of imagination for the rest.

 

Do you want to make a Mk1 or Mk2, if you want, let me know, but i don't move very fast, sorry.

TTFn Oily

[snakeyme 0]

Thanx oily, its the mk 2 I'm after and I have the wing still in 1 piece luckily (just needs tidying up), I'm also buying RCM&E every so often and I get plans from that 2 lol.

 

It will be interesting as to how well I do on the buildind side of things as I'm actually quite nervous tbh

[Peter Royall 47]

No worries, its just wood and glue!

Just trace your parts onto your wood, cut it out with a stanley knife (other makes are available)! And glue it together, piece by piece. The parts can be held together with elastic bands or masking tape while the glue sets.

PM me your address, and i can post you the drawings, or if you want to meet at the field on some pre arranged time and day?

TTFn Oily