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Electric Stunt => Gettin all AMP'ed up! => Topic started by: John Rist on April 06, 2017, 07:31:27 PM

Title: Sakitumi-E
Post by: John Rist on April 06, 2017, 07:31:27 PM
I have started my Sakitumi-E.  The wing and elevator are ready to be covered.  I am waiting on some 1/32 plywood to skin the fuselage for stiffness. I should be able to remove wood from the core of the fuselage to keep the weight the same.

I do have one question.  Should I offset the rudder any at all?
Title: Re: Sakitumi-E
Post by: john e. holliday on April 06, 2017, 08:51:41 PM
Follow the plan or go to Walters site and look at construction photos. VD~
Title: Re: Sakitumi-E
Post by: John Rist on April 06, 2017, 10:07:20 PM
Follow the plan or go to Walters site and look at construction photos. VD~

Unless I am blind the plans don't show that view of the rudder.  Walter's build log don't cover it either.  Pictures of his finished model aren't totally clear either.  It appears that their may be some offset but not sure.  I am guessing that some offset would be OK.
Title: Re: Sakitumi-E
Post by: Target on April 06, 2017, 11:51:15 PM
Normally the rule is to put in just a barely perceptible amount of rudder offset, so that it isn't offset the other way, if trying to set it centered.
They say too much offset makes for poor line tension in the overheads....
Title: Re: Sakitumi-E
Post by: badbill on April 07, 2017, 04:02:58 AM
I didn't use any offset, and couldn't be happier with the way mine flies.
Title: Re: Sakitumi-E
Post by: John Rist on April 13, 2017, 08:41:49 AM
In order to stiffen the fuselage I glued 1/32 plywood on either side.  To keep the weight down I drilled holes in the original fuselage.  I used Tightbond glue and weights to glue the sides on.  I also installed a fiberglass motor mount that is laminated to the plywood motor mount ring that came with the kit.  The finisher fuselage weighs 8.4 oz and is stiff as a base ball bat.  Beings it is now plywood all over it will take very little paint to make it look good.
Title: Re: Sakitumi-E
Post by: John Rist on April 17, 2017, 09:19:15 AM
Spinners for an electric setup, for me,  has always been a pain in the rear.  ???   I use pusher props and have had to cut out the slots for the LH prop (ugly).  You can buy LH spinners but they are $$$$$. Spinners also add rotating mass which is not a good thing.

So I came up with the idea to make a round disk with holes in it for cooling.  Fashion a noise block to round out the noise.  once all painted black I think it will look good and work well.   #^
Title: Re: Sakitumi-E
Post by: Avaiojet on April 17, 2017, 09:30:13 AM
John,

WOW!

Nice workmanship!  H^^

Nice build and great holes.

I'll be looking!

CB
Title: Re: Sakitumi-E
Post by: John Rist on April 18, 2017, 12:48:08 PM
Making sure tail feathers are square in every direction.  y1
Title: Re: Sakitumi-E
Post by: John Rist on April 18, 2017, 07:24:25 PM
Vertical all squire with just enough outward offset to insure it's not in.   #^
Title: Re: Sakitumi-E
Post by: John Rist on April 19, 2017, 04:37:16 PM
Temporally assembled to see what it looks like.  I am just realizing this is a big airplane.  It should fly great!   #^
Title: Re: Sakitumi-E
Post by: Avaiojet on April 19, 2017, 05:22:36 PM
Temporally assembled to see what it looks like.  I am just realizing this is a big airplane.  It should fly great!   #^

John,

Looking really good.  H^^

I made Sakitumi lettering for someone can't remember who?

Send me a PM or e-mail with your address and color, size, and I'll get some Sakitumi lettering out to you.

CB
Title: Re: Sakitumi-E
Post by: john e. holliday on April 20, 2017, 08:56:27 AM
Looking good.  I watched Dan McEntee fly his in St Louis and it looked great.  Of course it was IC powered.
Title: Re: Sakitumi-E
Post by: John Rist on April 20, 2017, 04:57:20 PM
Looking good.  I watched Dan McEntee fly his in St Louis and it looked great.  Of course it was IC powered.

John, do you by any chance know what Dan's Sakitumi weighs as a gasser?
Title: Re: Sakitumi-E
Post by: badbill on April 21, 2017, 06:06:06 AM
John, do you by any chance know what Dan's Sakitumi weighs as a gasser?

I haven't started on my nitro version yet, but my electric is 36.7 oz without the battery... Probably has 65-70 flights on it now. Still loving it!
Title: Re: Sakitumi-E
Post by: John Rist on April 21, 2017, 06:26:54 AM
I haven't started on my nitro version yet, but my electric is 36.7 oz without the battery... Probably has 65-70 flights on it now. Still loving it!

Thanks Bill.  I haven't  got a weight on mine yet but this gives me a target weight to work with.  #^
Title: Re: Sakitumi-E
Post by: john e. holliday on April 21, 2017, 11:21:39 AM
John, do you by any chance know what Dan's Sakitumi weighs as a gasser?

Contact him, he is on here once in a while.
Title: Re: Sakitumi-E
Post by: badbill on April 21, 2017, 12:54:44 PM
Thanks Bill.  I haven't  got a weight on mine yet but this gives me a target weight to work with.  #^

Just so you know, that was the weight with EVERYTHING, RTF but no lipo...
Title: Re: Sakitumi-E
Post by: John Rist on April 29, 2017, 06:52:21 PM
Life sometimes gets in the way of the fun stuff.  It may be a few weeks before I get back to finishing this project.  Getting new carpet and laminate flooring in the house.  At my age I work slow so it will take time to get the house ready for the carpet layers.   :'(
Title: Re: Sakitumi-E
Post by: badbill on May 31, 2017, 07:37:52 AM
You done with it yet?
Title: Re: Sakitumi-E
Post by: John Rist on June 01, 2017, 08:01:53 PM
You done with it yet?

The short answer is NO  n~.  However I just finished the honey-do list.  We have new carpet, new living room furniture, and a redone office.  So I am back working on the build.  Should have the wing covered in the next few days.  I have new batteries on order that should be in soon.  All is good  #^   #^
Title: Re: Sakitumi-E
Post by: badbill on June 02, 2017, 09:34:30 AM
The short answer is NO  n~.  However I just finished the honey-do list.  We have new carpet, new living room furniture, and a redone office.  So I am back working on the build.  Should have the wing covered in the next few days.  I have new batteries on order that should be in soon.  All is good  #^   #^

Very cool. I haven't even started on my Nitro Sakitumi kit yet, it's about two projects away still. I have many many flights on the electric though and still love it. I'm having new carpet installed on the 10th, but it will just be a one day job  #^
Title: Re: Sakitumi-E
Post by: John Rist on June 30, 2017, 07:28:51 PM
Wings covered and starting to paint fuselage and tail feathers.    y1   y1   #^   #^
Title: Re: Sakitumi-E
Post by: John Rist on July 06, 2017, 08:51:22 AM
Paint finished.  Ready for final assembly.  Won't be long now!  y1
Title: Re: Sakitumi-E
Post by: John Rist on July 11, 2017, 10:03:14 AM
Ready for first flight.
Title: Re: Sakitumi-E
Post by: John Rist on July 11, 2017, 10:04:14 AM
Wing decals
Title: Re: Sakitumi-E
Post by: john e. holliday on July 11, 2017, 10:33:50 AM
That does look nice.  I like it. H^^
Title: Re: Sakitumi-E
Post by: badbill on July 11, 2017, 10:57:31 AM
It looks great! Have you got an AUW yet , and how's the balance?
Title: Re: Sakitumi-E
Post by: John Rist on July 12, 2017, 10:29:52 PM
It looks great! Have you got an AUW yet , and how's the balance?

Haven't flown it yet.  The CG is spot on per the plans with the 2800 mah battery.  The ready for first flight specks are as follows:

Sakitumi-E
Kit by Walter Umland
48 oz ready to fly
Wing span 55-1/2"
Wing area 621 sq in
Battery 2800mAh 4-Cell/4S 14.8V ProLite X 25C LiPo by Thunder Power RC
Motor Cobra 2826/10 KV 930
Prop 11 x 5.5 EP
Speed controller TURNIGY Plush 60amp
KR timer set at 9200 RPM
Lines 62"
Title: Re: Sakitumi-E
Post by: Target on July 12, 2017, 10:44:49 PM
Sounds great John, but you better make those lines a little longer.
62" lines will make for a fast lap time I think.

I can't wait to hear how it flies, all kidding aside. It looks awesome.
Goodluck!
Title: Re: Sakitumi-E
Post by: John Rist on July 13, 2017, 06:37:13 AM
Sounds great John, but you better make those lines a little longer.
62" lines will make for a fast lap time I think.

I can't wait to hear how it flies, all kidding aside. It looks awesome.
Goodluck!

The good news is that with the KR timer I will be able to set the RPM at the field to adjust lap time. 
Title: Re: Sakitumi-E
Post by: badbill on July 13, 2017, 06:57:05 AM
I'm flying mine on 60' .015 and it seems perfect to me, though I am a hack. My videos are on the other thread. Looks like mine and John's ended up at near the same overall weight, with his airframe weight slightly more and battery slightly less since he is running a 2800 compared to my 3400 prolite X. I'm running a FM9 timer set for 5:45 minutes and I adjusted the RPM and many other settings at the field for my first 3 flying sessions with the Sakitumi till I got it perfect. I ended up at 10,500 rpm with a APC 12x6E and it is great in any wind.To me, the best thing about it is that it seems to be the same speed straight up or straight down, nice and manageable with plenty of time to think  y1
Title: Re: Sakitumi-E
Post by: John Rist on August 06, 2017, 05:58:16 PM
I now have about 10 flights on my Sakitumi-E.  Line tension is really good.  Goes where you point it.  Probably the best flying airplane I own.  Lap time are 5.1 seconds.  Final set up is:

Sakitumi-E
Kit by Walter Umland
48 oz ready to fly
Wing span 55-1/2"
Wing area 621 sq in
Battery 2800mAh 4-Cell/4S 14.8V ProLite X 25C LiPo by Thunder Power RC
4 minute flight charge back is 1868 MHA
Motor Cobra 2826/10 KV 930
Prop 12 x 6  EP
Speed controller TURNIGY Plush 60amp
KR timer set at 8900 RPM
Lines 60"

 #^   :D
PS at the end of a flight the battery is almost at room temperature and the motor is warm to the touch, not hot just a little warm.
Title: Re: Sakitumi-E
Post by: Dave Nyce on October 03, 2018, 04:47:17 PM
The plywood with the slots, does that go on the outboard side of the fuselage?
Title: Re: Sakitumi-E
Post by: Target on October 03, 2018, 05:47:52 PM
The plywood with the slots, does that go on the outboard side of the fuselage?

Check the pictures of this thread, particularly post #24, looks like the slots go on the inside in the yellow and black plane.
Title: Re: Sakitumi-E
Post by: MikeyPratt on October 06, 2018, 10:27:33 AM
Hi John,
Nicely done.  In my opinion 1/16” or 3/32” balsa whoul have been just as good as the plywood for less money.  Having said that, I’m sure it will be just fine and glad it it’s turning out for you. 

Later,
Mikey