Hip Pocket Builders' Forum

Indoor Free Flight Forum => EZB, 35cm, Ministick, AROG, Livingroom Flyers => Topic started by: Skymon on June 06, 2017, 04:01:53 AM



Title: first indoor - ministick build
Post by: Skymon on June 06, 2017, 04:01:53 AM
In the UK it's chucking it down with rain. So my CLG antics have stopped for a while.
In the relative shelter of my living room I've started a ministick build.
The plane is a plan I found of a Miniquark.
It's full of rather interesting measurements with many decimal places...
I've converted them all to metric and tried to cut some wood to an approximation of the actual sizes.
Progress has been good with a few slip ups on the way.

I've struggled with a few things.
Making the tissue tubes for the wing posts was a nightmare.
I took a number of attempts, but finally got there with something I hope is a tube.

I had an issue with adhesive. I bought some Duco and attempted to thin it down with acetone...
No good, it just ends up as a furry lump.
In the end I sued a wood glue thinned with acetone.
It took ages to dry but hopefully the joints will be strong.

I'm putting this together as a first time build to learn the techniques and processes.
I'm not expecting it to be a lightweight or a great flier, but I hope with everything I learn I can do a better job next time.

If anyone has the time to reply I'd like to pose a few probably straightforward questions...

1 - building board. I used a strip of old 1/4" balsa, but I noticed it wasn't that flat. What do you use as a nice flat building board that you can stick pins in to easily?
2 - Adhesive for indoor specifically. I see talk of the legendary Ambroid and also of Duco that can be thinned with acetone. I tried Duco and it doesn't react well to acetone. What's an easily available UK adhesive?
3 - dimensions for ribs, spars, etc... my pan shows dimensions like 0.035" x 0.045" - which one is which? vertical first or horizontal??

My shopping list for this build has been intriguing my wife...
She's seen guitar strings, dress making pins, nail polish remover, a bag of 'clingfilm' and tiny rubber bands turning up. She's confused.

I would like to thank John at Flitehook for being an awesome supplier !

Happy flying
Si


Title: Re: first indoor - ministick build
Post by: frash on June 06, 2017, 08:21:09 AM
I did not look back at the plan, but I think that the larger dimension (0.045-in) for the wing spars goes vertical. If I'm wrong, surely someone will respond.

Fred Rash


Title: Re: first indoor - ministick build
Post by: Rossclements on June 06, 2017, 09:20:36 AM
I use coroplast for my building board. You can get them from the makers of the signs or just wait until the local elections are done and take some. It works pretty good as long as you don't put a pin in one of the vanes.

Ross


Title: Re: first indoor - ministick build
Post by: Skymon on June 07, 2017, 08:26:16 AM
I spent a few more hours on this plane last night.
I'm learning a lot on the way.
Making pigtail motor bearing was very difficult and took a lot of examples to get right.
I've not been that stringent on the building light methodology yet, I've been using CYA glue when I need a quick fix, just to move along with the build.
My tissue wing post tubes were very chunky.
Covering was reasonably painless but I know I went overboard on the spray mount :)
Forming wet balsa is another new one on me, that went reasonably well - hot water helps over cold.

The model is just over 0.5g so far, so over the min weight limit already but not too bad for a first go.

I have the tip plates to add now, trying to work out how to do that without sticking the wood to the covering.
I realised I fitted a stab end plate in the middle as a fin, that isn't right, so it'll have to come off and be replaced tonight.

I will be trying to build a propeller tonight, another voyage of discovery.
Looking to do my maiden flight on Thursday of all goes well.


Title: Re: first indoor - ministick build
Post by: Olbill on June 07, 2017, 11:10:41 AM
I don't understand the Duco problem. I've used it for years and never had anything like that happen.


Title: Re: first indoor - ministick build
Post by: ram on June 07, 2017, 11:25:57 AM
I don't understand the Duco problem. I've used it for years and never had anything like that happen.

My guess is the issue is with the quality of the acetone and not the Duco unless there is a different type of Duco sold in Europe.


Title: Re: first indoor - ministick build
Post by: Skymon on June 07, 2017, 11:43:07 AM
I used 'nail polish remover' and it's got other stuff in the ingredients.
I have a bottle of 99.9% pure acetone on the way now...
I'll see if that helps.


Title: Re: first indoor - ministick build
Post by: jakepF1D on June 07, 2017, 12:03:20 PM
I'm not sure what's available over there, but I also frequently use lacquer thinner.  It typically contains acetone along with some other solvents that evaporate a little slower.  I occasionally have issues with blushing when using acetone because it evaporates so quickly, and lacquer thinner usually solves the problem.

As for the spars and ribs, almost without exception the larger dimension will be the vertical height on any indoor model. 


Title: Re: first indoor - ministick build
Post by: Skymon on June 08, 2017, 03:34:11 AM
I started the prop build last night.
It took me four attempts as the sanding process proved tricky...
I started with 1/32 balsa and cut out the lighter parts from the lightest sheet I had.
Used a spot light to work out where the dark areas were and avoided them.
One blade came out nicely at around 0.2mm and then I proceeded to mash up two more blades when my sanding block caught the root.
On my fourth attempt I was successful and I had a matching blade.
The first came in at 0.05g and the second 0.07g, so I sanded the second blade until it evened up.
It as pretty thin now.

Both blades were soaked in hot water and wrapped around a bottle last night.
Tonight they come off and I start to make up my first prop.

One thing I've learned with this indoor building stuff is that you can't use the traditional puff of air to clear balsa dust form the building board - everything else goes with it!



Title: Re: first indoor - ministick build
Post by: Skymon on June 08, 2017, 03:35:17 AM
When building up the prop do I need to add something as a thrust bearing so that the balsa hub doesn't stick on the pigtail bearing?
I have some thin ptfe sheet...


Title: Re: first indoor - ministick build
Post by: Olbill on June 08, 2017, 07:08:39 AM
Yes. Teflon works great. I always use 2 washers. Maybe unnecessary but it makes me feel better.


Title: Re: first indoor - ministick build
Post by: Skymon on June 08, 2017, 06:27:18 PM
Well she's done!
I learnt that props turn anti clockwise and that nail varnish remover is not the same as pure acetone.
I got my glue thinned although it vaps off very quickly and it leaves a cyanosis type frosting.
I have completed a few laps of the bedroom and I now need to learn how to make it turn tighter.
I also need to learn how to wind and install rubber.
I have no idea what thrust angle i have or what trim is best but it flies!
Si


Title: Re: first indoor - ministick build
Post by: Skymon on June 09, 2017, 03:32:21 AM
Some pics of the finished ship


Title: Re: first indoor - ministick build
Post by: hastf1b on June 09, 2017, 04:45:51 AM
Mount the stab better for left cirkel.

Heinz


Title: Re: first indoor - ministick build
Post by: Skymon on June 09, 2017, 07:56:22 AM
that's a severe boom offset!
OK, I'll give it a go.
I wonder about making a prop where I can vary the pitch - with tissue sockets.
I have no idea what pitch my prop is...

I have a long way to go
:)

Have a super weekend


Title: Re: first indoor - ministick build
Post by: hastf1b on June 09, 2017, 08:49:51 AM
The drawing should be just an example, but the left circle should be.
Propshaft with tissue sockets can be made.

In the beginning, it is always good to build by a plan.

Have a look at here for the prop pitch: https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=9&cad=rja&uact=8&ved=0ahUKEwjouZagi_PTAhWEeSYKHYYGAo8QFgg8MAg&url=https%3A%2F%2Fwww.rcgroups.com%2Fforums%2Fshowatt.php%3Fattachmentid%3D2890778&usg=AFQjCNEsm_-38uC76es0ctLz18NOUQoDjQ&sig2=kyGxZxKxHujrWKpZ2gWGBA


Heinz


Title: Re: first indoor - ministick build
Post by: Rossclements on June 09, 2017, 10:31:47 AM
Or here http://www.hippocketaeronautics.com/hpa_forum/index.php?topic=21539.0
You can also use left thrust help turn the plane.


Title: Re: first indoor - ministick build
Post by: Hepcat on June 09, 2017, 07:49:53 PM
Skymon,
Making tissue tubes can be frustrating at times but you get better at the right amount of cement to use after a while.  For a long time I kept a piece of 16swg wire clean and polished with a bit of brass tube sliding on it to help push the paper tube off. Later I learnt to rollthe tissue with about 1/4 " of tissue overhanging the end of the wire.  As soon as possible after rolling I pinch the overhanging tissue between thumb and finger and pull it off the wire.  I then try to drop it on the bench without further touching to let it dry off. Cut to length later with a very sharp blade (as from a disposable razor.

Recently I did a propeller for an indoor model (but not as light as a ministick) and wanted to be able to vary the blade angle.  The first picture below shews the hub. Two pieces of 1.32" ply 1"x0.125". The prop shaft with some balsa as thick as the wire are stuck to one piece of ply and then the other side stuck in place. In the next picture two strips of printer paper are stuck on one side of the hub. The prop blade has a 1/16" dia. spar sanded down from a cocktail stick. This is held on the edge of the hub and the end of the paper strip is pulled over the spar and glued to the other side of the hub.  Make sure the blade can rotate and later glue a couple of wraps of tissue over the paper.

John


Title: Re: first indoor - ministick build
Post by: Skymon on June 12, 2017, 03:29:24 AM
I completed a new plane over the weekend, a K777.
Here's a short youtube of it flying around my bedroom with 200 turns on some short rubber.
I'm probably going to start another design tonight.
https://youtu.be/HCqB8nHMrWY (https://youtu.be/HCqB8nHMrWY)

Having a lot of fun learning these new building techniques.
Not sure that I'm creating top end example, but they fly and I now know a lot more about these lightweights than I did before.

Si


Title: Re: first indoor - ministick build
Post by: hastf1b on June 12, 2017, 03:44:13 AM
Very nice, congratulations. :)

Heinz


Title: Re: first indoor - ministick build
Post by: Skymon on June 12, 2017, 09:59:54 AM
That's the Quark in the video not the K777...
I have yet to film the K777 as it's not quite as well trimmed.


Title: Re: first indoor - ministick build
Post by: fitnezz on June 12, 2017, 04:49:43 PM
Dont hesitate to give 2000+ turns in your bedroom in place of 200 ;) Here ie my RIP K777 floating and bumping around:

https://www.youtube.com/watch?v=B3F2EZ3wCps


Title: Re: first indoor - ministick build
Post by: Skymon on June 13, 2017, 04:37:59 AM
that's super! I love the colours :)
I weighed all of the parts for both planes last night and they are quite similar in weight.
0.78 for the Quark and 0.73 for the K777.

My motor stick for the Quark weighs as much as the minimum weight for this class :)

I'm likely to build another this week, possibly the 'record' plan.
And I'm quite tempted to build another Quark and try to get the weight down.

My props seem to be about twice the weight they could be at 0.2g
I guess I need to sand just a little more...

I got the quark to complete five circuits of the room last night, took about 30 seconds.


Title: Re: first indoor - ministick build
Post by: fitnezz on June 13, 2017, 01:58:10 PM
Don't get obsessed with cutting down weight too much;) I was making this mistake in place of focusing on what is really important in the beginning of my journey. My 0.8g mini with bamboo LE/TE/winglets (on stab and prop) and foam prop blades was giving over 3 minutes constantly in my tiny area.  Important thing when flying in a bedroom and small area. Prop P/D should be very low as for minis. around 1.4 for my area or lower. Forget about 1.8 or something. My good minis were using 7" props, others 6" or 6.5" 0.2g prop is really ok. Also lots of washout on the right and washin on the left. Bit of boom left offset, small stab slant. A touch of left and down thrust. And you get your mini flying for minutes in your living room. Good luck!


Title: Re: first indoor - ministick build
Post by: Skymon on June 14, 2017, 02:58:08 AM
I'd like to aim for reducing weight for a challenge and to gain a greater insight in to the indoor building techniques.
It's quite a dramatic change to see a plane float about when my experience up to now has been pinging catapult gliders at 100MPH+.
I've cut up a drinks can last night to see if I can make a thrust bearing out of it.
I'm also going to try a mini with a curved wing and stab outline, just because it'll look nice.
I think, as you say, props are right at the core of good performance when you have such a tiny wing.
I will be building up a prop construction jig and I fancy a go at one with tissue tubes at the root so I can fiddle with pitch.

I think the thrust bearing interface could also do with some improvements as I fell there is a lot of friction there when under tension.

It's all very interesting and great fun and I appreciate the help and guidance from this forum.

Si


Title: Re: first indoor - ministick build
Post by: fitnezz on June 14, 2017, 10:07:44 AM
Yeah thats all fun things todo! About the bearing, really go for a pigtail bearing. You can see how I did that in a video underneath. After few wire bendings gets in blood ;) Allows for thrust settings and props exchanging. If you dont have teflon washers, hard plastic from soda drink caps, i.e. red cocacola cap does the job well enough!

https://www.youtube.com/watch?v=xGmP43LpLGk


Title: Re: first indoor - ministick build
Post by: Rossclements on June 14, 2017, 01:43:09 PM
This is another good source!
https://www.youtube.com/watch?v=IAnm1gXUyx4&t=66s


Title: Re: first indoor - ministick build
Post by: Skymon on June 15, 2017, 03:08:26 AM
I made a lot of progress last night on my second Quark.
I spent a while selecting what I felt was light wood.
I have a nice 1/4 inch sheet that I stripped some sections off of the edge.
My fuse and stab are now half the weight of my original one - at 0.23g
But I feel the boom is a little tender.
So I contemplated changing it for a tougher piece of balsa, but then I thought, hey why not build a lighter stab instead?
That's tonight's challenge. This will also reduce the weight even further.

I tried an aluminium thrust bearing but it snapped so I went back to a pigtail and it worked ok.
Went down a size in the wire across the model. Having thinner wire helped in forming it up.

I ended up with a wing that is the same mass as my first one, despite using nicer wood.
I think I went a little too chunky on the sections especially for tip plates and ribs, but it's nice and sturdy.

Si


Title: Re: first indoor - ministick build
Post by: BR549 on June 16, 2017, 07:31:27 PM
Keep at it with the thinned Duco. It's been a revelation for me since I got it figured out.

I got some micro-applicator bottles from Hobby Lobby. Put some acetone in the bottle, squeezed in some Duco than mixed it. Then fiddled with the mixture until I got a consistency that works for me. Now I double and triple glue all my joints and they a super strong.

Bob


Title: Re: first indoor - ministick build
Post by: Skymon on June 20, 2017, 05:39:08 AM
I got ministick three in the air last night.
It came in at 0.54g which is a lot better than my first at 0.85
Weight loss was mainly due to better wood selection for the motor stick.
Quark 1 had a stick weight of 0.47, this one has a more svelte 0.23. I did have to change the boom though as my first was a little too flexy.
It didn't even register on my scales... the second hits it at 0.02.
I have ordered more accurate scales just though :)
I also used 10 music wire all the way through instead of the mix of 10, 11 and 12 called for in the plans.
I had a heck of a job trimming it until I realised the wing was on back to front!
I'm really not happy with the friction on the prop, it seems to drag when wound.
When there is no rubber the prop turns on the slightest waft of air, but loaded it just doesn't seem to rotate freely.
I'll see what I can do in the way of washers and stuff tonight.
I had some pictures but they seem to have fallen off of my phone...


Title: Re: first indoor - ministick build
Post by: Hepcat on June 20, 2017, 07:24:08 AM
Skymon,
Your willingness to try things and keep going WILL bring success.  Just a couple of thoughts on the rough running propeller: did you grind and sand the front of the front loop  on which the washers run and did you keep the washers small, certainly not more than about 0.06" diameter.  Also you mentioned cutting down all your wire diameters, which is good because steel is heavy, however if you went to 0.01" diameter for the propshaft it could easily be bending under the load of a wound motor and binding, particularly in the pigtail.
John


Title: Re: first indoor - ministick build
Post by: Skymon on June 20, 2017, 11:27:56 AM
John
Thanks for the input.
I did grind down the front of the bearing with a dremel.
I've got no washers in there yet, I've ordered some thin ptfe sheet and I've got a few punches to cut out small discs.
I was going to drill a clearance hole in the sheet and then pop a disc out with my hole cutter.
I've drawn a blank on teeny tiny washers.
I was also going to cut a tiny square of drinks can, drill a hole in it and add it to the back of the prop.

One thin I don't like is the side thrust on the prop shaft, it looks very ungainly to have the shaft not running parallel to the rubber.
Must be some side loads on the bearing.
I've added a tiny dash of GT85 to the bearing to lube it and the motor has silicone lube on it.

I am energised by the need to tweak and experiment, learning a new skill is a big driver for me. I like the fact I can learn how adjusting the wing, the stab and the prop affect the flight pattern. I can see possibilities for a Taguchi DofE exercise to show the interactions :)

I'm off to the park tonight to sling cat gliders skyward, the weather here is tropical!
I'm so near the one minute mark on my Sweepette 8".

Many thanks for taking the time to read my posts and offering help and advice.

Regards
Si


Title: Re: first indoor - ministick build
Post by: Rossclements on June 20, 2017, 02:02:25 PM
Of you don't like the left thrust n the bearing check out Bill Gowen's models, It is a nifty solution!

Ross


Title: Re: first indoor - ministick build
Post by: Skymon on June 21, 2017, 03:09:20 AM
Are they the ones with the rubber on the side of the stick?
I guess the stick flexes and creates an offset.

I can see the offset is done for a reason, it just clashes with my engineering experience of aligned drivetrains.


Title: Re: first indoor - ministick build
Post by: Skymon on June 21, 2017, 05:30:32 AM
Here's my latest Quark on the scales at 0.57.
Still a way to go to get the 0.43 minimum, but a worthwhile advance.


Title: Re: first indoor - ministick build
Post by: Rossclements on June 21, 2017, 07:07:08 AM
No, Look at one of his plans in the gallery. The wingposts are set up differently than normal.
I cant post the plan here.

Ross


Title: Re: first indoor - ministick build
Post by: frash on June 21, 2017, 07:54:53 AM
Bill Gowen puts one wing post on one side of the motor stick and the other wing post on the other side of the motor stick to give left thrust with a straight prop hanger. This leaves motor and prop in a straight line with the motor stick.

Fred Rash



Title: Re: first indoor - ministick build
Post by: Skymon on June 21, 2017, 08:07:58 AM
Aha!
Neat solution :)
I'll have a look - are these ministick designs?


Title: Re: first indoor - ministick build
Post by: Skymon on June 21, 2017, 08:10:43 AM
I got them - LPP and A6 and F1M.
The F1M looks a bit like a ministick but bigger.
I like that idea but I guess it depends on endplates to 'steer' the plane.


Title: Re: first indoor - ministick build
Post by: Skymon on June 21, 2017, 08:12:45 AM
Another please for advice.
I have been adding turns to my motor and have got to the point where the model doesn't like to climb. It appears to be suffering a lot of torque where the inside wing drops and it enters a death spiral.
Running on the lower turns it glides nicely loosing a little height each rev, but when I go above 400 turns it really suffers...


Title: Re: first indoor - ministick build
Post by: adanjo on June 21, 2017, 01:21:57 PM
Another please for advice.
I have been adding turns to my motor and have got to the point where the model doesn't like to climb. It appears to be suffering a lot of torque where the inside wing drops and it enters a death spiral.
Running on the lower turns it glides nicely loosing a little height each rev, but when I go above 400 turns it really suffers...


Add wash-in on the left wing. Or, wash-in on the left and wash-out on the right wing, and add a little more angle of attack on the wing.
Aki


Title: Re: first indoor - ministick build
Post by: Skymon on June 21, 2017, 01:33:36 PM
Looking at the wing it has a subtle twist giving exactly the opposite effect.
Time to correct that...


Title: Re: first indoor - ministick build
Post by: Rossclements on June 21, 2017, 02:04:07 PM
The tip plates help a bit, but the motor stick effectively has left thrust. I have done this on a few A-6 models and it seems to work well.


Title: Re: first indoor - ministick build
Post by: Skymon on June 21, 2017, 02:15:37 PM
I straightened the wing first then added a lititle wash in toothed inboard tip and yay, it works.
Then I added a tiny piece of drinks can to the property as a washer and now I'm tapping the ceiling!
Fantastic.


Title: Re: first indoor - ministick build
Post by: Skymon on June 22, 2017, 07:32:06 AM
Many thanks for the help and assistance yesterday.
I found I had a number of issues.
1 - Friction. My prop has no bearing material at all, just balsa on steel wire. I added a tiny scrap of aluminium drinks can (2mm square) with a hole in it to the prop shaft and glued it to the hub. The result was a great increase in revs and power. From a slowly sinking pane to a plane that was tapping the ceiling on 400 turns.
2 - Wash in/out. My wing was warped, in the opposite way to what's required. Using a little steam I straightened it out, then I used a bit more to drop the trailing edge of the inside wing. I had no idea what wash in was before, I know understand it is effectively changing the angle of attack of the wing across it's span. So there is a little more lift from the inside corner that keeps the plane level. This worked really well and I now understand a concept I've been hearing and reading about for years.

It's all great progress!

As a result of understanding wash in, I added a bit to the tip of my Sweepette 8" CLG and I got my best time ever - 56 seconds in some really still air last night. I am now looking at building another one with better wood in an effort to break the minute :)

Best regards and thanks for all the help
Si


Title: Re: first indoor - ministick build
Post by: Skymon on June 27, 2017, 02:47:37 AM
I popped in to K&P Aero and picked up a winder last Friday and I've been adding lots of winds.
My lightest QUark was circling the ceiling last night, with the prop pinging every now and then, on 600 turns.
Pulling rubber from a stooge and getting it on the plane really is a hidden art!

I've got in contact with Tony Hebb and I've printed his entry level 35 out.
So I could be on the way to an indoor event one day...

Thanks for the help along the way

Si


Title: Re: first indoor - ministick build
Post by: Skymon on July 05, 2017, 08:25:31 AM
I attended my first indoor event last night.

Thanks Ian!

I had a great time. A very friendly bunch of guys were flying.
I had help with pretty much every aspect of flying.
I borrowed all sorts of kit, had rubber donated and lent and I even used some glue to repair my prop bearing.

I learnt a lot!
Trimming wings, incidence, wash in, prop pitch, rubber turns, torque, winding, etc, etc!
All advice freely given in a very friendly manner.

I've spent the morning ordering wood and 'bits' and looking through plans.

Although the ministicks are fun I'm heading for larger territory and I will be attempting to put together one of Tony Hebbs 35cm models.

I'll post my exploits up here for your amusement :)

Two important things I learnt - get a bigger kit box with things in it and don't forget the reading glasses!!

Si



Title: Re: first indoor - ministick build
Post by: Skymon on July 24, 2017, 03:10:29 AM
I've finally made a ministick under the min weight.
The prop was the biggest lump of mass on my plane, thanks to some decent 'indoor' weight wood I managed to get it down in weight.
All of my props so far were approx. 200mg, I got this one down to 130.
Not a massive achievement when there are 200mg EZBs out there, but a nice bit of progress for me.
I fell I have enough ministicks now, with four in the cabinet.
So I'm off on the F1L route now.
I'll be tackling the motor stick first, doing a bit of weighing and tensile testing.
It'll be the classic hobby shopper.


Best regards
S