By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by CML

SIG Kadet LT-40 Build - My first proper build!

Warts and all build by a beginner - I don't know how this is going to turn out!!

All Topics | Latest Posts

Search for:  in Thread Title in  
Percy Verance20/07/2019 13:12:37
avatar
8109 forum posts
155 photos

Hi Nu Me

I don't want to come over as being over-critical, but it's not always a good idea to remove all the parts from their sheets. They're often best left in situ until actually required, as it avoids damaging or misplacing them. smiley  Lite ply in particular is very prone to damage if mishandled.

And if you have the space, get somethig like a wallpaper pasting table with a rug or something similar on it. You can place assembled sub structures on this, and the rug/long pile carpet will help to avoid dings - often known as hangar rash.

 

 

Edited By Percy Verance on 20/07/2019 13:17:16

ASH.20/07/2019 13:43:22
avatar
293 forum posts


Door frames are the main culprits when it comes to hangar rash.. laugh

There's a certain way to carry fuselages indoors - tail first!

Edited By ASH. on 20/07/2019 13:45:58

Nu Me 120/07/2019 14:25:02
51 forum posts

Thanks for the comments guys. I am not worries about people offering critique, This is a warts and all thread that people may find informative and entertaining in the future.

Started the build and in the first 2 glues realised that one of them was wrong blush. Managed to separate them with the help of a sharp blade and no lasting damage done. The first few pieces go down.

I struggled to see how some pieces went together. There appeared to be gaps and the drawing showed what looked like strengthening blocks. Looking through the Instruction Book again, a few pages in I could see what was supposed to go where and why. The gaps were to fit the pieces to connect the wings together later in the build. Shown dry fitted in the picture.

Sorted the parts and started to fit the ribs. Then realised that I should be fitting the spars as I go. Fitted the spars.

There is a fair amount of trimming, sanding and cutting to get things as flush a possible. A couple of, almost sticky finger moments but now I think that things are as per the plan.

Although I have read through the Instruction Book, I would have done better reading half a dozen pages in more depth as well - so I would have got a better understanding of what was going to fit where, and why.

Percy Verance20/07/2019 16:33:39
avatar
8109 forum posts
155 photos

Nu Me

The bit for joing the wings in the middle is the dihedral brace - there may be a smaller rear one as well. Don't glue those in with superglue, as it's not the best glue for that job because it would be too brittle. Some would use epoxy, but my choice would be Aliphatic as it soaks into the wood for a better bond.

Nu Me 120/07/2019 19:00:27
51 forum posts

Thanks Percy thumbs up

Well, with a little more glue, some reading and time the wing started to look complete.

Luckily, while I was in Wickes this morning I picked up a couple of clamps too.

Right wing is now assembled. The clamp is to weigh the wing down while the glue dries. I have gone around a lot of rib and spar joints with some Aliphatic resin..

The supplied dihedral jig to set rib one is not very precise. The angled side is more slope than flat - or at least it appears so. Time will tell if the angle I have set is correct.

Percy Verance20/07/2019 20:00:18
avatar
8109 forum posts
155 photos

Nu Me

If you have a tiny gap once you've joined the wings, it needn't be an issue. You could simply fill the gap with Aliphatic glue. It might be best to leave joining the wing until much later. Because once you have joined it you'll find it awkward to move the wing around the shed, or wherever it is you're building. Once the wing is finally joined, you could strengthen the joint greatly by wrapping a 3 inch wide bandage (as in medical gauze bandage) round the centre where the plywood brace is. Coat the bandage in 2 or 3 coats of Aliphatic, and it'll be plenty strong enough. As a nice bonus the iron on covering film will stick to the dried Aliphatic really well.

I just noticed the ailerons, or rather the lack of. Are these cut away later?

 

Edited By Percy Verance on 20/07/2019 20:02:54

Percy Verance20/07/2019 20:04:15
avatar
8109 forum posts
155 photos

Ooops, I just spotted the strip ailerons on the plan. For some reason I was looking for insets.......

Peter Miller20/07/2019 21:07:34
avatar
10016 forum posts
1185 photos
10 articles

As you are finding out. Reading ALL the instructrions while studying the plan is essential to understand it all before you start.

I have, in the past had to assist with building a Sig kit by remote control.

I have also had someone building one of my most popular designs.They failed to read the instructions or follow the sequence and made a right dogs dinner of the whole thing. The really irritating thing was they they are a club member. They will NEVER get any help from me in future

Edited By Peter Miller on 20/07/2019 21:08:04

Nu Me 120/07/2019 22:10:38
51 forum posts

Thanks for the comments.

Percy - Yep, the ailerons are still to be attached on the trailing edge. The kit comes with the bandage to join the wings.

Peter - It must be painful to watch someone butcher something you have designed. I just need to slow down a little and understand before I glue.

Well so far it has been a mixed bag. I am enjoying the building but making silly mistakes. A few lessons learnt today - and thanks for all of the suggestions. The board is working very well. and the covering is a very thin dust sheet, normally used for covering things while painting. I am cutting strips off it so the multipack will last for the whole build - easily!

Day 1 over and nothing I am aware of has stopped play too much. I am thinking of adding an additional sheet to the top leading edge of each wing. It will help the tape stick when I join the wings.

Percy Verance21/07/2019 09:32:42
avatar
8109 forum posts
155 photos

Hi again Nu Me

Just be sure to complete each wing panel as much as possible ( sheeting etc) before you actually lift it from the board for the first time. That way you'll minimise the risk of warps creeping into the structure. Store the first wing on a flat surface if possible while you build the second one....

Looking good so far.....yes

P.S. Sounds a bit silly I know, but watch out for the basic mistake we've all made at some point, particularly when building fuselages. Be sure to build handed sides :ie one left and one right. It is easy to get carried away with the build progressing so quickly........

Nu Me 122/07/2019 13:03:12
51 forum posts

Thanks Percy thumbs up

Right wind trimmed and initial sanding completed. The ailerons are fitted after the wings are joined together.

A good clear down. Level check and ready for the left wing.

Left wing started. I have placed the drawing with more space on the wing joining area. When I set the dihedral angle on the right wing the space I had left on the left side was a little tight.

When sanding the completed wing there were a couple of high sports on joins. I have got a couple of the off cuts from the right wing spars.....

.

..and and will use them as top of wing shear depth gauges.

GrumpyGnome22/07/2019 13:09:34
avatar
503 forum posts
145 photos

Gosh, that's a difficult way to do shear webs. I tend to glue them to the vertical faces of the spars - can be less critical of length then sand them down.

But I suppose SIG have made more kits than I have!

GG

Percy Verance22/07/2019 13:36:20
avatar
8109 forum posts
155 photos

I'd have to agree GG. Like you I usually glue them to the front face of the wing spars, although I have built models with them on the rear face of the spars too. Sig's method could be slightly stronger, but there can't be much in it.

Don't fit the ailerons permanently until after the wings are covered and finished Nu Me. It's a total pain trying to cover a wing with ailerons fixed in place.

 

 

Edited By Percy Verance on 22/07/2019 13:43:35

Peter Miller22/07/2019 13:40:56
avatar
10016 forum posts
1185 photos
10 articles

I like them on the front face of the spars becase I use clamps to hold the top sheet down to the spar.

jez_21.jpg

Nu Me 122/07/2019 14:00:48
51 forum posts

Interesting? The Instruction Book shows them in the position

Percy - The ailerons need to be part fitted and part dry fitted before covering I have ordered the Iron.

Don Fry22/07/2019 14:11:57
avatar
3735 forum posts
42 photos

What Percy was allududing to was, standard practice is dry fit the hinges, ailerons, and get a good fit. Then fix permanently after covering, when you just need to punch a hole, slit the covering to insert the hinges. Word of warning, this last bit will cause confusion if you hadn't made sure you know left aileron from right aileron, and sometimes top face from bottom face. Too easy to mark the wood, and cover the marking, and forget to put, say a bit of masking tape on the covered surface to keep it known.

Nu Me 122/07/2019 16:04:36
51 forum posts

Thanks Don. The ailerons are operated by a bent wire that goes through a groove in a yet to be glued piece of wood fitted to the trailing edge. The ailerons themselves have a hole drilled in them to put the end of one end of the wire and are asymmetrical - I believe.

Don Fry22/07/2019 16:33:46
avatar
3735 forum posts
42 photos

Word for the day, the bent wire is a "torque rod", and it does, as a pair give one up, one down movement, if attached to opposite ends of a servo arm.

Nu Me 122/07/2019 18:49:38
51 forum posts

Thanks Don.

Not being ready for talking about Torque Rods yet wink I did a little more on the left wing.

Only one delivery today; the number 3 handle to go with the number 10 blades I have brought.

I am a lot happier, so far, with this wing build. Using the off cut to gauge the depth SHOULD mean that less sanding flush will be required.

I have a number of items at various stages in the postal system.

Hopefully more tomorrow. Thanks for all of the advice and critique.

Percy Verance22/07/2019 18:55:39
avatar
8109 forum posts
155 photos

Torque rods? Not seen those being used for some time. Still, this model will have been designed a few moons ago. Not that it will be any worse for that. What might eventually happen - if the rods are using the balsa as a bearing - is wear will creep in and it'll all get sloppy and imprecise. If the rods have plastic bearings then all will be well. The rods are intentionally bent to be asymmetrical Nu Me, in order to provide some aileron differential movement.

I'd still fit a servo in each wing personally.......

Edited By Percy Verance on 22/07/2019 18:58:31

All Topics | Latest Posts

Please login to post a reply.

Magazine Locator

Want the latest issue of RCM&E? Use our magazine locator link to find your nearest stockist!

Find RCM&E! 

Support Our Partners
Addlestone Models
CML
Pepe Aircraft
Wings & Wheels 2019
Gliders Distribution
Cambridge Gliding Club
electricwingman 2017
Slec
Advertise With Us
Sarik
Latest "For Sale" Ads
Does your club have a safety officer?
Q: Does your club have a safety officer, or is the emphasis on individual members to each be their own safety officer?

 Yes we have a SO
 No, it's down to everyone

Latest Reviews
Digital Back Issues

RCM&E Digital Back Issues

Contact us

Contact us