Decathlon 98 1/4 scale Rc guys New Build ;) Few Questions - RCCanada - Canada Radio Controlled Hobby Forum
RCCanada - Canada's Radio Control Hobby Forum
Construction Ideas, Hints and Tips For all the builders out there. Ask questions, make suggestions, trade tips.

Reply
 
Thread Tools Display Modes
Old 02-13-2020, 02:54 PM   #1
k4cz0rpl
RCC Apprentice
 
I am: Tomasz Zajac
Join Date: Oct 2013
Location: Mississauga
Radio of choice:
X20S,Dx8G2
# of RCs: 4

Feedback: 10 / 100%
Posts: 52
Total Props: 0
Decathlon 98 1/4 scale Rc guys New Build ;) Few Questions


       Remove this ad - become a site supporter!
Hey.
I am looking for some answers and small help with my build.
This is my 1st airplane that need some work to be done but I am familiar with scale because before I flew GP yak 55M and members of the club help me to get some knowledge about builds and I spend lots of time to fixing it. (last year crashed )
Details about airplane can be found here:
http://www.rcguys.com/decathlon.htm

To make this easier for me and you guys I will upload some pictures.
So I bought this as ARF with most of servos installed and without engine.
Engine is GP36R.
As u can see in the pictures I am slowly getting this baby ready for season.
Engine is mostly installed but something do not let me proceed forward because Im not sure if engine has been installed correctly.
In airplane manual I cant find how far engine should be from firewall but because cowling is long i had to do some extra spacing between firewall and engine standoffs.Thats the piece of wood for extra spacing.U can see it in picture here:



Now there is enough (1/4-1/2 of inch from front cowling ) space to install propeller.
My biggest question is:After the engine is installed and airplane is in level (horizontal as in flight) - is engine should be in level to ;to the air frame?
Im thinking not because it should be a bit down and right due prop is moving
I will add that the piece of block that I installed as spacing have same measurement on each side.So thickness,length and height.
So picture from the top look like that:


Question 2:
Is this ignition module not installed to close to engine?I mean its hard to place is inside due very limited space on the tray.








I tryed to hold airplane in level and I used self leveling laser to see how engine is installed compare to air frame.

I would welcome and sugestions and help.
Im sorry if this is a bit overthinking but I dont want to lost airplane in 3s.
Thanks
Tomas
Attached Thumbnails
Click image for larger version

Name:	20200213-151634.jpg
Views:	409
Size:	100.3 KB
ID:	1662243   Click image for larger version

Name:	20200213-151734.jpg
Views:	339
Size:	88.7 KB
ID:	1662245   Click image for larger version

Name:	20200213-151652.jpg
Views:	339
Size:	154.3 KB
ID:	1662247   Click image for larger version

Name:	20200213-151656.jpg
Views:	370
Size:	166.6 KB
ID:	1662249  

Click image for larger version

Name:	20200213-151700.jpg
Views:	357
Size:	145.0 KB
ID:	1662251   Click image for larger version

Name:	20200213-151604.jpg
Views:	397
Size:	151.9 KB
ID:	1662253  
k4cz0rpl is offline   Quick reply to this message.

Sponsored Links - Subscribe to remove this ad.
Old 02-13-2020, 06:19 PM   #2
Ronno
RCC Contributor
 
I am: Ron L
Join Date: Jan 2004
Location: London

Feedback: 29 / 100%
Posts: 376
Total Props: 0
Re: Decathlon 98 1/4 scale Rc guys New Build ;) Few Questions

Thomas ,I am currently working on the same airplane.
The firewall has the correct amount of down and side thrust already built in.
Just keep your engine square to the firewall.
There are a few in depth threads on this airplane and plenty of information to be had ie,
Some later kits had longer cowls ,some had incidence issues and needed roughly 1/4" of down elevator trim to fly level.
On mine ,I am 6 7/8" from firewall to prop drive plate.
I also made some changes to the front end to aid in cooling ,as is on yours there is very little area for the hot air to exit the cowl.
Attached Thumbnails
Click image for larger version

Name:	20200213_190229.jpg
Views:	72
Size:	541.1 KB
ID:	1662305   Click image for larger version

Name:	20200213_190304.jpg
Views:	70
Size:	509.6 KB
ID:	1662307   Click image for larger version

Name:	20200213_190344.jpg
Views:	68
Size:	422.3 KB
ID:	1662309   Click image for larger version

Name:	20200213_190424.jpg
Views:	76
Size:	311.5 KB
ID:	1662311  

Ronno is offline   Quick reply to this message.
Old 02-13-2020, 06:33 PM   #3
k4cz0rpl
RCC Apprentice
 
I am: Tomasz Zajac
Join Date: Oct 2013
Location: Mississauga
Radio of choice:
X20S,Dx8G2
# of RCs: 4

Feedback: 10 / 100%
Posts: 52
Total Props: 0
Re: Decathlon 98 1/4 scale Rc guys New Build ;) Few Questions

Ronno thx for answer.
So I couldn't mount engine as urs to firewall because I would be around 1.1/4 inside cowl.
So thats why I need to add extra spacer (wood block).
I didnt thought about cooling yet so I will use ur method to do something similar.
How am I gonna check if engine is square to firewall.
If my block is square (all sizes are equal on each side) then it should be fine.Is it?
k4cz0rpl is offline   Quick reply to this message.
 
Old 02-13-2020, 06:50 PM   #4
Ronno
RCC Contributor
 
I am: Ron L
Join Date: Jan 2004
Location: London

Feedback: 29 / 100%
Posts: 376
Total Props: 0
Re: Decathlon 98 1/4 scale Rc guys New Build ;) Few Questions

As long as the block is the same thickness or the firewall side and engine side are parallel,you are good to go.
I could have used a block as well,,but I decided to make longer stand offs instead of using the ones supplied with the engine (DLE 35RA).
My cowl overlaps the firewall roughly 3/8" to 1/2"
Long story short,I bought the airplane from RC Guys two years ago ,it was one of the last three in stock.When I got it home I removed all the covering,changed the wing servo mounts ,added flaps,made the additional cooling changes to the front end,double beveled the stab and elevators for more surface deflection and re covered it in Ultracoat.(just finished the re cover yesterday)
Ronno is offline   Quick reply to this message.
Old 02-14-2020, 04:15 AM   #5
cassat
RCC Supreme Contributor
 
I am: Dave
Join Date: Jul 2004
Location: P.River,Alberta
Radio of choice:
Airtronics Aquila,Taranis,DX7
# of RCs: 12

Feedback: 211 / 98%
Posts: 7,363
Total Props: 11
Re: Decathlon 98 1/4 scale Rc guys New Build ;) Few Questions

Nice photos. I can see the right thrust angle built in. Also looks like 1 1/2 degree downthrust angle.

I had the same question about the ignition module picking up heat from the engine block. Even with extra cooling cut in the cowl bottom, is it ok ?
I guess the other thing is the ignition wire length is going to hang out the bottom quite a bit?
cassat is offline   Quick reply to this message.
Old 02-14-2020, 07:59 AM   #6
Ronno
RCC Contributor
 
I am: Ron L
Join Date: Jan 2004
Location: London

Feedback: 29 / 100%
Posts: 376
Total Props: 0
Re: Decathlon 98 1/4 scale Rc guys New Build ;) Few Questions

On mine ,The cooling duct is removable so I can put the ignition behind the firewall under the gas tank.
I like to keep it away from the heat whenever possible.
Attached Thumbnails
Click image for larger version

Name:	20200214_084736.jpg
Views:	61
Size:	500.3 KB
ID:	1662351  
Ronno is offline   Quick reply to this message.
Old 02-14-2020, 10:27 AM   #7
k4cz0rpl
RCC Apprentice
 
I am: Tomasz Zajac
Join Date: Oct 2013
Location: Mississauga
Radio of choice:
X20S,Dx8G2
# of RCs: 4

Feedback: 10 / 100%
Posts: 52
Total Props: 0
Re: Decathlon 98 1/4 scale Rc guys New Build ;) Few Questions

Im thinking to do same cooling as Ronno.Then maybe i will cover ignition modul in aluminium foil (same as for baking) -but i will need to do some testing.That is why i order digital thermometer to see temps.The wire for ignition is not a problem so I had similar idea as Ronno.Between muffler pipes and use zip lock to attached left over cable to firewall.
Cassat are u taking about my photos?
So u think angle is ok?
k4cz0rpl is offline   Quick reply to this message.
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the RCCanada - Canada Radio Controlled Hobby Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

Member names may only be composed of alpha-numeric characters. (A-Z and 0-9)

!!ATTENTION ADVERTISERS!! If you intend on advertising anything on this forum, whatsoever, you are required to first contact us here . Additionally, we do NOT allow BUSINESS NAMES unless you are an Authorized Vendor. If you own a business, and want to do sales on this site via posting or private message, you will need to follow the rules. Shops, Stores, Distributors, Group Buys without being authorized will see your account terminated.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Radio of choice?
Which radio is your current favorite to use?
Number of RC Vehicles?
How many boats, cars, planes do you own?

Log-in



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
vBulletin Message

Thread Tools
Display Modes

Forum Jump


All times are GMT -5. The time now is 04:51 PM.


vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2024 DragonByte Technologies Ltd.