Nakki II plans released for free download

In these strange days one needs something to do. So download from link below an rather old, design for free building.

Link to plans.

If you manage to get something flying pls. send me pic :).
Video of my version:

Heinonen HK-1 Keltiäinen Peanut Scale

Heinone HK-1 Keltiäinen is one of those planes which touch heart of almost all middle aged aviation enthusiast in Finland. This was an single-seater, hobby-built plane. It was designed by Mr. Juhani Heinonen and built by himself. Despite some sources saying that only one was built, there is actually two other examples built. But the builders of those planes made a number of modifications to plane and used type name HK-1B.

Original plane is quite cute and it looks like it popped out of some 50’s comic. It has extremely easy design which is easily transformed into model aeroplane. This example has been drawn into Peanut scale.

As an kit this is actually old. I originally draw this year ago, but the model got swamped by other activities. Now it is ready for publication and available at good model shops.

VL Viima II peanut short kit

New kit has been released ot VL Viima II. This is an 1935’s biplane, used for Finnish airforce training. Structure’s are simple, but the small scale and number of parts makes it rather complicated to build. Design is based on original factory plans so this is rather good Peanut scale adaptation of original. For further info of original plane see this
(photo by Ilmailuliitto / Suomen Ilmailumuseo, used with permission)

This is short kit, meaning it includes laser cut balsa wood parts. No hardware or strip wood included. Model can be purchased from excellent

New design, PIK-26 Mini-Sytky in Peanut scale

An new Peanut-scale kit was published some time ago. You can purchase it from–pik-26-mini-sytky-peanut-scale

It is rather exact scale short kit. I scaled it from my larger plans and made minor adjustements to facilitate smaller size. Kit contains laser-cut balsa parts. No hardware or balsa strips etc. included.

IVL K.1 Kurki – peanut plan

If you check my last post (see here) you might notice that I sound overly enthusiastic of this ugly duckling. You are pretty right.. This is truly one of ugliest planes I have seen and it is also of finnish origin.

It was designed in 1927 by Asser Järvinen. He was employed by Finnish state aviation factory (IVL = Ilmavoimien Lentokonetehdas, directly translated airforce airplane factory..). Originally this plane was his pet project which he designed without permission. But the need for planes was so great that initial design got accepted as an official project.

Good intentions do great things, but not in this case. When plane was completed it turned out to be overweight and challenging to fly. For many reasons. There is an good wiki page for it. Strangely enough this is categorized as an military, transport & training plane.

After extensive testing, some 55 test flights it was concluded that it is of ‘no practical use’. Project was scrapped and only existing plane was stored for prosperity. That is museum. It ended up in Vesivehmaa museum where it was stored in sad condition. Check my previous visit there.

After while good people of Finnish Aviation museum decided to restore it and the end result is much nicer. But still it is ugly plane.

Well, that does one do when one encounters something so extraordinary? Obviously one must make model aeroplane out of it. I did some initial design drafts couple years ago. Then after new Kurki exhibition opened in decemeber 2018 at museum I decided to complete design. For several reasons I decided to make an peanut scale version of it.

So here it is for your viewing and building pleasure. Enjoy.

Click here to download plan.

I strongly propose that you visit Aviation Museum (Ilmailumuseo) to see this plane in it’s 1:1 glory. It is sight to see, and the  IVL Kurki special exhibition is open to end of january 2019. Nice place to visit in so many ways!

This plan has been released for free download. If you manage to make something out of it pls send me pics of that. I would love to hear whether it flies….

Getting better scanning results from vintage plans

Now with better time I have been tuning my processes for better scans. For mini-review of scanner see here. This is continuation article of that mini-review, but these comments apply also to any scanner.

1. First, if plan is really vintage, try ‘Document type : Grayscale CAD/map’ instead of normal colour. For example, see below:

with colour

with Grayscale CAD/map

This is rather counter-intuitive, but idea is to let scanner do automatic removal of yellowish tint. It performs rather nicely.

2.  Do not use high resolution.

Changing resolution from normal (300) to fine (600) dpi creates rather large files and makes things much more complicated. Using 600dpi resolution creates A1-scans of PDF-size 16mb. And if you open that file and make some changes you end up with 200+ mb workspace and 150mb files. Which are just too much.  Using 300dpi has enough resolution for normal model aeroplane plans.

3. Use backing paper if plan is really fragile.

Use normal A0/A1-roll paper as backing if plan is almost schreds. Just tape leading edge of plan to paper with small pieces of tape (3M Magic Scotch). Note that use as small amount of tape as possible and only on leading edge. By leading edge I mean the edge which goes into scanner.

really brittle plan with all kinds dents.

taped to paper, nicely and safely waiting for scan

4. If plan is vintage drafting paper then do following

  • scanner can do wonders with yellow tint removal, but it cannot help translucent drafting paper hue. You can try to use backing paper to make effect smaller, but it does not work well enough

Plain Grayscale CAD

Graysale CAD with paper backing.

  • Get adobe photoshop, elements is just fine and use Levels-tool. Move white end from right side to the left part of black curve. See below.

Using levels

And then you get much more clear plan.

Good enough.

The plan in question and further info of this nice -30’s biplane can be found here.

Large format scanning & mini-review of Contex SD One MF 36″

I have always been struggling with finding original aeroplane plans. Normally you do not find them despite that almost everyone at field and in events says ‘yeah you just go there, plans are there’. Typically I get comments like ‘yeah I saw the plans there in seventies, they must be still there’. Once I found out that the building where they were supposed to be had been demoslished decade ago.

Anyway, the key question is getting the plan. Then second question is to get plan in electronic form. ie. to scan it. You can get that service from printshops but there are couple issues. a) it is expensive, typical cost for scanning full size plane plans is around 200-300€. b) those printshops do not concentrate when they scan plans. They do not worry things like scale, is paper straight, …. Producing scans which are not optimal.

To solve this issue I have been dreaming of getting own full size scanner. They are really expensive and large, requiring storage space. But all this has now changed. Contex introduced slightly smaller unit couple years ago and the price is not totally out of reach. Product was named Contex SD One, then upgraded to SD One+ and finally SD One MF. Scanner comes in three sizes 24″, 36″ and 44″ with 36″ corresponding A0-roll size. Colortrac introduced similar model. Contex SD One MF model has also large screen allowing non-tethered use and scanning to network and usb stick. This is actually quite important as it reduces amount of stuff needed to make scans.

Couple months ago I decided to purchase Contex SD One 36″ MF. Main reason is to be able to make scans of original plans to allow more precise models. Also I want to get full control of workflow eliminating printshops and the errors they seem to cause. Scanning is obviously more economical per page, but the cost of scanner itself is still huge for hobby company.  Being portable allows me to drag scanner to museums and make scans there. Also it allows me to store scanner away when not used.

Scanner arrived couple days ago. Packaging is rather large as axpected, unit weighs approx 12kg so it is not lightweight. When setting scanner up I noticed that the scanner activation key was incorrect. It was key for some other scanner as the serial number and model was incorrect. Also, I simply do not understand why this activation was necessary. Quick call to local Contex representative and couple days wait solved this issue with new activation key. One should note that you can use scanner which has not been activated, there is 50h usage limit and I do not know what happens if that is exceeded. While setting scanner up I noticed that it kept hanging up occasionally. I guess that this was caused by factory installed firmware version, 4.0.1-002. I updated firmware to 4.0.1-010 which can be found at Contex website. Updating was straightforward and painless procedure.

User interface of scanner is rather nice. There are no keys in scanner and everything is done via rather large touchscreen which is extremely responsive. I could enjoy better contrast, but all in all screen is great. Also there are limited editing possibilities (preview, adjust, crop and annotate, contrast, color, …) via screen, which I have not tried. Update 2018-02-20 : I have tried editing functions and they actually work rather well. But they are slow.

Then to scanning. First I noticed that this scanner produces really nice looking files. I tried several settings and quickly landed to rather nice set of settings for typical plans.  I wanted to get rid of yellow tint and get reasonable resolution. Scanning is quite fast with these settings, I have not clocked it but  I have no reason to suspect advertised speed of 4.8cm/s. My selected settings are :

  • Quality : normal (300) or fine (600) dpi
  • Document type : Grayscale CAD/map
  • Validation : no
  • Size : auto
  • Format : PDF. Using TIFF creates rather large files but it might be usable in special cases. For jpg files you can specify compression, default is 80.

I have made several scans but still I am experimenting. To see example of typical resulst check this link. It is an F1A0-glider Salko. Designer is unknown, but if somebody knows him pls let me know it as I want to credit him for great looking plan.

You can output scanned files to several locations, but there is an major gripe regarding cloud destinations.

  • USB – scan is output to memory stick, works great. Update 2018-02-20 : However – I have experimented using small portable hard drives with USB-connection. This does not seem to work reliably, even if the drive functions properly with PC. I suspect that the current requirements of drive’s are more than scanner circuit can produce. With couple drives some work, some not. And those which work do not work reliably. USB interface in scanner supports USB 3.0 specification and complains if you try to use USB2 memory. Documentation does not state maximum size of memory stick.
  • Email – scan to defined address or addresses, works great
  • PC – scan file to PC, you need to install Contex.LINK application to pc. Pls. note that scanner is connected to PC via LAN/Wifi. Ie. USB connection is not used. Actually this is great as it allows much more freedom in cabling etc. Then again, in sites where you have no connection to network it is not so great as then there is no connection. Using memory stick removes that problem.
  • Dropbox, Box, Google Drive, OneDrive. These destinations require installing Contex.LINK to PC.  This has been implemented in such way that scanner outputs scan to PC which then relays scan to cloud destinations. This is not nice as the whole idea of scanning directly to cloud is … compromised. I tried Dropbox and it seems to work nice, but I still wonder that is the PC really necessary. IMHO this is kludge. All in all, it works.
  • Rainforest365 – this is some kind of cloud teamwork sharing site/app in IOS & Android which is currently in beta so cannot say more about it.

Manual also mentions that you could use USB connection to link PC and scanner using third party application. I think that this is unnecessary, as I am not aware of any applications utilizing it. For example the well known scanning solution Vuescan by Hamrick does not list any Contex scanners on their supported scanners page.

One thing notably missing is the ability to scan directly to network drive (ie. NAS or similar). I suspect that one could try to define scanning directory in PC which is really an NAS directory visible from PC. Again this is not nice approach as the PC is unnecessary element.

One thing worth mentioning is that scanner can also do copying. This is done by first scanning material and then automaticly outputting file via defined large format printer. This seems to be nicely implemented but I have not  (yet) tried it.

Regarding network in general, scanner can be connected to normal LAN using cabling or Wifi with supplied Wifi-USB-dongle. This works nicely.

To summarize:

  1. Scanner produces great looking scans and it is quite fast.
  2. Connectivity is great, but cloud scanning seems to be somewhat kludge.
  3. Scanner is large, but given the paper size is quite compact

All in all : rather nice scanner producing good results.

For next episode of this mini-review see ‘getting better results with vintage plans.’.

(pls. note that I am in no way affiliated with Contex or their local distributor

Rolled vs. folded plans

This is kinda sad thing. As the cost of mailing has increased I have had to make changes to product packaging. When I started this business 8 years ago I decided that I will not never ship folded plans. Mostly due the fact that folded plans are not good for building. I kept that idea for ages but then mailing costs kept creeping up. And couple years ago they crept up really. Also, Finnish postal services stopped delivering maxi-letters inside Finland. They had to keep delivering them outside Finland, so that did not really matter too much.

But then the prices jumped a bit. Last time I shipped rolled plans the cost of mailing was more that customer paid for plans. That was approx 25€. Which is bad. Really bad. Same plan shipped in envelope (folded…) cost approx 6€.

So some time ago I started changing all delivery statements in my pages ( to not include promise of rolled plans. Currently all plans ship folded.

I know this is not optimal for some builders. So if you need rolled plans pls. contact me and I can arrange shipping rolled, with some extra cost. Also, when you order short kits plans are rolled.

Free downloads / 3d-models at our site(s)

Okay, some time ago my extranet-site of main eCommerce site ( broke down. I got some comments regarding problems with it’s id system which is extremely simple and straightforward. As there is very little commercial value on those items which are downloadable via extranet I decided to make things simpler. This is to remove all user id systems of extranet and re-create it here.

So now all freely downloadable stuff has an separate index-page which is visible at top menu of this site. That means, all files which are supposed to be on old extranet and files presented in this blog have their place in index. And there is no user id’s to remember (or distribute for that matter).

Direct link to index-page.

There is possibility of human error here. I tried to gather all files which were supposed to be in old extranet, but… I might have missed something. That happens. Contact me if you miss something.

HowTo : Model aeroplane transport supports for light trailer

Here in Finland (and in many other Nordic & European countries) we have thing called light trailer. They are, as name states, light trailers for transporting things like sacks of gravel, soil, leaves, etc. Or lawn mover. Nice and handy, somewhat economical and come in different sizes. We have had numerous debates on what is The Best Way to use them for transporting your modelling stuff. Hopefully in one piece. This HowTo tries to explain one way to do it. There are numerous attempts, this just my humble way. It does have it’s merits as I’ll soon explain.

Before starting : get an trailer which has both leaf springs and shock absorbers. If you opt to buy cheaper model which has only leaf springs and possibly rubber grommets to limit movement of wheels you will be sorry. That type of trailer is extremely jumpy. And it will break your planes soon enough.

Key reasons of structure:

  • It has unlimited adjustability, as everything is based on matrix of attachment holes it can be modified easily.
  • It is not screwed to trailer. It holds in place because of main timber elements are sized so that they do not move.
  • You can pick support up from trailer easily in case you need to use trailer to something not so nice. Like transporting dirt.
  • When not in flying season it can be easily dismantled and stored for next season.
  • If you get new trailer, or as I dream of getting mobile home you can make new set of matrix structure (longitudial and cross elements) and supports are again usable.

I will explain the structure via an number of pictures. You should check out rough sketch I draw of the design. Check it here 169-01 Transport support 01. (yeah, strange name? project 169, sheet 01, version 01..).  Pics enlarge by clicking them. Hover over pic’s to read captions.

Everything starts with empty trailer. You need plenty of timber to make this structure. Best timber is fully planed and corners rounded. Actually it is (almost) most economical stuff here. Good lumberyard is your friend. First elements must be full-length compared to trailer floor. You must drill holes to to centerline of timber with distance of X between hole centers. This is not critically precise. Just keep distance constant. I used one short plank as an guide. Suitable distance is approx equal to timber width. ie. 95 x 19 timber = 10cm distance. Hole size should be 1mm (or 2mm) larger than screw size. I am using screw size 6mm (= M6) so hole should be 7/8mm. To get suitable size check your blind nut size.

At the same time you should cut crossing timber, again covering the whole floor of timber. I use approx 3 longitudial pieces and 5 crossing pieces. My trailer is 3m x 1,3. Again, drill holes with same measurements. Then proceed on making needed number of supports. Some rough examples are in drawing, feel free to design more. Send me pic if you build something awesome :).

EDIT : Corrected screw size. It was supposed to be M6, ie. 6mm screws etc.

Pictures for your viewing pleasure: