Lesson by Mitch: 1. Braiding Rubber Motors

Ask other modelers for a little help / knowledge ?

Re: Lesson by Mitch: 1. Braiding Rubber Motors

Postby Chris A. » Tue May 20, 2014 8:58 pm

The Me109 is also a favorite of mine but I agree the wingspan and area are just too small for the weight. The 109E will fly, but not long in cruise. To work around the problem, has anyone ever made and flown the 109T or the 109H versions? The T version is basically an extended wing 109E that was adopted for Germany's proposed aircraft carrier. It actually served on some tiny airbase in the Baltic for point defense. The 109 H was a later attempt to build a high altitude fighter/photo recon version in which a stub center section of straight taper was used and the standard wing panels then attached. The horizontal stabilizer was also enlarged and braced. It was service tested in France, flew at very high altitudes, but withdrawn as the wings fluttered in a dive. Both would add wing area with minimal weight. Thoughts and comments?
Chris A.
 
Posts: 92
Joined: Tue Apr 01, 2014 10:50 am

Re: Lesson by Mitch: 1. Braiding Rubber Motors

Postby Mitch » Tue May 20, 2014 11:14 pm

After I finish my current 109E for the Blitz on Poland I will be getting back in my Garage Workshop where I am current building the Z. (Me109 Twin) I started a post on that and plan to get back to that soon. As I showed in my post for "Building a 400 series plane for $20" Once you build one and save the plans. Buy a few replacement laser sheets and a few plastic parts from Guillow's and build another. In my future Me109's I plan to omit the plastic cowling and will make different versions. I also made a FW Ta-152 from Guillow's FW-190 kit, but that was a bit more work to convert. I plan to eventually build all the Me 109 versions. But the next FAC contest will be for the Blitz and the Battle of Britain, all Me-109 E's, so for now it's all Emils!

...however I believe the 109 has an advantage by having a long fuselage, thereby providing room for a longer motor. I believe the key to success is the proper motor/prop set up... But take all of my opinions with a grain of salt. I am still learning with the rest of us... Mitch
Mitch
 
Posts: 1347
Joined: Mon Aug 22, 2011 9:16 pm
Location: Kent, WA

Re: Lesson by Mitch: 1. Braiding Rubber Motors

Postby davidchoate » Thu May 22, 2014 1:49 am

Thanks for pulling up this thread. I was just planning on trying this braiding technique on my lancer.
davidchoate
 
Posts: 1263
Joined: Wed Aug 14, 2013 6:41 am
Location: PHiladelphia PA

Re: Lesson by Mitch: 1. Braiding Rubber Motors

Postby Mitch » Thu May 22, 2014 8:33 am

I believe braiding is important when the motors start getting longer. It keeps the rubber together and it knots up and releases better. You can also use the same technique to braid 3 or 4 loops. I have only done 2 loops and maxed out at 2X hook to peg. I believe you can go up 5X hook to peg! The trouble with models like the Lancer and Arrow is the fuselage is so narrow. For more rubber I think the 'fatter' models would have an advantage like the radial engine Zero and FW. I hope to pack in the rubber in my 1000 series Hellcat! But first I have to BUILD IT! Mitch
Mitch
 
Posts: 1347
Joined: Mon Aug 22, 2011 9:16 pm
Location: Kent, WA

Re: Lesson by Mitch: 1. Braiding Rubber Motors

Postby hunterdude » Thu May 22, 2014 10:12 am

Due to A to Z closing I just acquired my first 1000 series...A Hellcat! I have yet to build a 400 series but will be building the bf-109 this summer...I would LOVE for Guillows to make a 1000 series bf-109! -Ben
hunterdude
 
Posts: 49
Joined: Thu May 08, 2014 10:22 am

Re: Lesson by Mitch: 1. Braiding Rubber Motors

Postby Mitch » Thu May 22, 2014 12:32 pm

Getting a bit off topic, but that's okay.

You need to understand the 400 and 1000 are all the same scale (1/16). The 1000 are larger models because they are larger planes. The Me109 is the smallest WW2 fighter that I know of.

You can follow my 'Blitz' thread to see the way I am now building the 109. You can follow Guillow plans exactly and still have a flyable model. I am building for FAC competition.

I plan to build the 1000 Hellcat in the near future. The 1000 Hellcat is the same scale as the 400 Zero. I think I can pack a lot of rubber into the body of a Guillow's Hellcat! :twisted:

Not only do I want my Hellcat to be a Zero killer... I have my sights set on an ally and a friend... My target is Don DeLoach's Wildcat. I have seen this plane fly for over a minute and it was beat out by Herb's Yak in Arizona. Don said Herb had more rubber. I am still learning and getting better. I think if I can build the Hellcat light enough and get the motor/prop set up right... I will be up against FAC's best flyers!

Mitch
Mitch
 
Posts: 1347
Joined: Mon Aug 22, 2011 9:16 pm
Location: Kent, WA

Re: Lesson by Mitch: 1. Braiding Rubber Motors

Postby twospruces » Fri May 23, 2014 6:21 am

Mitch, great info thanks.

I am curious though as to why this is improves the motor? is it just more rubber?

thanks.
twospruces
 
Posts: 96
Joined: Tue Nov 20, 2012 9:27 pm

Re: Lesson by Mitch: 1. Braiding Rubber Motors

Postby Mitch » Fri May 23, 2014 7:25 am

That's a good question and you are reaching to the level of my limited knowledge. I believe the knots build up and release better than if the motor was not braided. Remember, guys in competition are using motors that are at least 2x hook to peg length. I have been told that you can go 5x hook to peg! That's why length is not so important, it's the mass of the rubber. Moreover I have seen a lot of set ups with many loops of rubber. It makes a nice package being braided.

I have heard of some motors releasing from front to back and the weight distribution throwing off the cg of the plane. Remember I am focusing on FAC competition. Before this I have flown just by following Guillow's instructions... however they do make reference to using more rubber for longer flights and stretch winding!

That's the best I can give.

Mitch

PS Now I think you can understand why ALL the guys (and gals) at FAC are using 'Blast Tubes' when winding. When one of these motors breaks at near full load it makes quite a racket! :o

Image
Miss B. Haven in Perris CA, with motor 2x hook to peg at rest.
Problems with model: 1. Rear peg too far back 2. Model too heavy 3. Nose hard to adjust 4: No Washout in wings 5: Need more dihedral
Performance : Flew for 6 seconds and was out in the first round.

NOTE: If I moved the rear peg fwd 2 bays (to the star) and used the same motor, the motor might be 3x or 4x hook to peg. Some of the FAC guys go by the weight of the finished model and use that as a reference to determine the weight of the motor. So they don't care about how long it is, they are looking for the proper power delivered for the weight of there plane!

Image
Miss Scarlet in Denver CO, being prepared for combat!
Problems with model: 1. Nose plate not secured in position. 2. Broke a Prop in test flights and installed an unbalanced prop!
Performance: Flew erratically at take off. With the power of a fully wound engine, the nose piece slipped out of position. Plane flew level and straight ahead nearly hitting the CD. I had to shout "INCOMING" and he stepped aside! Model crashed under near full power and started tumbling. The wing came off (magnets) but the tail will need to be rebuilt!
Mitch
 
Posts: 1347
Joined: Mon Aug 22, 2011 9:16 pm
Location: Kent, WA

Re: Lesson by Mitch: 1. Braiding Rubber Motors

Postby davidchoate » Wed Jul 09, 2014 3:18 pm

I just wanted to pull this up so I can try at it again.
davidchoate
 
Posts: 1263
Joined: Wed Aug 14, 2013 6:41 am
Location: PHiladelphia PA

Re: Lesson by Mitch: 1. Braiding Rubber Motors

Postby davidchoate » Wed Jul 09, 2014 3:27 pm

Mitch, Is it normal that the Rubber motor extends so far long away from the Nose ? I have problems when the motor hangs out with the prop hook coming off, and the motor going inside the fuselage.
davidchoate
 
Posts: 1263
Joined: Wed Aug 14, 2013 6:41 am
Location: PHiladelphia PA

Re: Lesson by Mitch: 1. Braiding Rubber Motors

Postby Steve Blanchard » Thu Jul 10, 2014 1:40 pm

David,

It is important that you have a snug fit for the noseblock in order to not only keep the prop in the plane after the rubber has unwound but also to maintain all of the thrust adjustments you made while trimming. It is quite normal to have a motor that is anywhere from 1.5 to 4 times the length of the hook to peg distance. You will need to either braid or backwind the rubber motor or use a spring tensioning device to make sure the motor doesn't bunch up and throw off the CG.

I hope this is helpful.

Steve
Steve Blanchard
 
Posts: 343
Joined: Tue Jun 14, 2011 10:08 am

Re: Lesson by Mitch: 1. Braiding Rubber Motors

Postby davidchoate » Fri Jul 11, 2014 6:21 pm

Thanx mitch. I am slowly getting better at FF. My current build, though not as light as I had hoped, Is still my lightest yet. I see how that onn FF models as compared to RC weight is critical, and sometimes component strength must be sacrificed to achieve low weight AND BALANCE. I'm beginning to understand about things like washout, and dihedral. A year ago I had no understanding of these things, but with much crashing and failed flights over the last year, I have learned much.
davidchoate
 
Posts: 1263
Joined: Wed Aug 14, 2013 6:41 am
Location: PHiladelphia PA

Re: Lesson by Mitch: 1. Braiding Rubber Motors

Postby WIDDOG » Fri Jul 11, 2014 7:01 pm

thought I would add a quote from Bill Hannan's book Peanut Power "Motor lengths of 1 1/4 to 2 times the distance between the prop hook and the tail peg are common." Don Ross's book Rubber Powered Model Airplanes ... " The length should be about 1 1/2 times the length from post to hook."
WIDDOG
 
Posts: 872
Joined: Tue Aug 25, 2009 5:34 am
Location: West Virginia USA

Re: Lesson by Mitch: 1. Braiding Rubber Motors

Postby scigs30 » Sun Jul 13, 2014 2:06 pm

I think everyone here knows I love Guillows kits and flying them, but these big Guillows build are another story . They are great laser builds but the wings are way too heavy making for a good flying model a challenge. I love converting these to Electric, they fly Awsome. If you want a good flying larger WWII bird try building the old Comet Mustang or Golden Age Reproduction kit. I gave up on these larger Guillows kit with old die crunched wood. Now with laser cutting they are my favorite electric birds.
scigs30
 
Posts: 844
Joined: Mon Nov 06, 2006 11:31 am

Re: Lesson by Mitch: 1. Braiding Rubber Motors

Postby Mitch » Fri Jul 18, 2014 5:02 am

Thanks to Everyone... and I am glad you pulled up my old post. I am home for a day. I have not been building lately, but still follow these posts. For the 400 series, I have now been dropping half the wing ribs, removing some wood from the fuselage frames, and using contest balsa on SOME (non structural) longrons, and making the tails as light as possible.

I believe these 400 series can be competitive, and definitely will fly well in your local flying field.

I am still VERY new to the competitor part of our hobby and my primary mission is to have fun and share my enthusiasm.

I was very hopeful for Miss Scarlet, But my nose block was not secured well and that was her downfall. She flew very well under half power during her test flights, and I wish I had pictures of that, but sadly do not.

Thanks to all, Mitch
Mitch
 
Posts: 1347
Joined: Mon Aug 22, 2011 9:16 pm
Location: Kent, WA

Previous

Return to General Building Questions

Who is online

Users browsing this forum: Bing [Bot] and 5 guests