Go Back  RCU Forums > RC Airplanes > Profile and Fun Flying Planes
Reload this Page >

Need a Profile, 20cc gas

Notices
Profile and Fun Flying Planes If you're a profile fan or into fun flyers than this is the forum to discuss those topics.

Need a Profile, 20cc gas

Old 05-01-2021, 07:27 AM
  #26  
LarryFitch
Junior Member
Thread Starter
 
Join Date: Oct 2020
Location: West Richland, WA
Posts: 28
Likes: 0
Received 1 Like on 1 Post
Default

The questions continue. I am ordering a short kit of the MoJo 65 from Lasercut USA today. I need a bit of help with two questions. First, should I order the fiberglass tubes for the fuse as noted on the plans, or get carbon fiber tubes? A bit lighter, and more bucks. Second, what do I use for landing gear legs? Is there anything appropriate available commercially?
Old 05-02-2021, 11:38 AM
  #27  
ahicks
My Feedback: (2)
 
Join Date: Aug 2008
Location: Waterford, Mi/Citrus Springs, Fl
Posts: 3,808
Received 14 Likes on 13 Posts
Default

I'd order the fiberglass tubes. The plane is already a fly weight with an absolutely ridiculous power to weight ratio. I generally save stuff like the gear when a plane goes in hard, but if I needed a set, bending up and drilling a set from flat stock purchased at a hardware would be no big deal.
Old 05-03-2021, 12:01 PM
  #28  
LarryFitch
Junior Member
Thread Starter
 
Join Date: Oct 2020
Location: West Richland, WA
Posts: 28
Likes: 0
Received 1 Like on 1 Post
Default

Thanks Mr. Hicks. I agree with using the fiberglass tubes. Think I'll use an aluminum wing tube, and bend up some landing gear from 6061 aluminum flat stock. The fellow that owns LasercutUSA does a beautiful job cutting the MoJo 65. A flying buddy of mine has one of the short kits, and I looked it over yesterday. As nice a cutting job as I've seen in quite a while. Can't wait to get one of my own.

Larry
Old 05-07-2021, 06:43 AM
  #29  
LarryFitch
Junior Member
Thread Starter
 
Join Date: Oct 2020
Location: West Richland, WA
Posts: 28
Likes: 0
Received 1 Like on 1 Post
Default Flight control hardware?

Can any of you folks that have, or are, flying a 65" profile recommend servo sizes and servo arm lengths for the airplane? I'm guessing 250-300 oz-in torque, and maybe 1 1/2" servo arms? I'm intending to use Dubro-style machine screw control horns, likely M3 size. Thinking about using Pro Modeler mini sized units that support HV and high torque. Think these might help shed a few ounces behind the CG. Thoughts, recommendations?
Old 05-07-2021, 08:21 AM
  #30  
daveopam
My Feedback: (9)
 
daveopam's Avatar
 
Join Date: Oct 2002
Location: ELK CITY, OK
Posts: 7,695
Received 21 Likes on 20 Posts
Default

Larry on my 72" Fusion I'm using a 330oz on the rudder but only 230oz on the elev and aile. I do have 2 elev servos so if you are using 1 I would increase. I also use the Du-Bro arms. I think they are 2" with 4-40 rods and ball links. I just use one battery for everything. It's a 3300 LiFe. I can get 3-4 flights on it. No problems with this set up so far.
I switched engines last week but haven't got to fly it yet. I had a DLE20 on it and switched to a Valley View 26cc.
I think I have a new set of fiberglass profile gear somewhere if you are interested. I would send it your way for what the shipping cost.

David
The following users liked this post:
ahicks (05-08-2021)
Old 05-07-2021, 09:36 AM
  #31  
LarryFitch
Junior Member
Thread Starter
 
Join Date: Oct 2020
Location: West Richland, WA
Posts: 28
Likes: 0
Received 1 Like on 1 Post
Default

David, thanks for the useful information, and wonderful offeron the gear legs. My zip code is 99353. Let me know what you need for shipping, and thanks again for the help.

Larry Fitch
Old 05-07-2021, 12:35 PM
  #32  
daveopam
My Feedback: (9)
 
daveopam's Avatar
 
Join Date: Oct 2002
Location: ELK CITY, OK
Posts: 7,695
Received 21 Likes on 20 Posts
Default

Larry, let me put my hands on them and give you dimensions first. If they will fit your needs I'll get your address and mail them and then give you the total. Probably do all that through PM so your address isn't on here.

David
Old 05-08-2021, 03:52 AM
  #33  
ahicks
My Feedback: (2)
 
Join Date: Aug 2008
Location: Waterford, Mi/Citrus Springs, Fl
Posts: 3,808
Received 14 Likes on 13 Posts
Default

I learned about receiver "brown out" and did a lot of testing on a similar plane quite a while back. Since then, I run 2 switches on all of my single battery systems. This for redundancy (I've lost one too many planes due to faulty switches), AND to provide the potential for up to double the available amperage to my flight pack. Passing all of the flight pack power/amperage through one standard JR type connector is not something I would endorse for servos this size on a plane designed to fly like a MoJo can be flown.

I would also second Dave's thoughts on servo selection and setup. Too, on my planes, any 4-40 rod length of consequence gets run through carbon fiber tubing to keep it stiff. Something I started doing a long time ago.

Best of luck on the build! -Al
Old 05-08-2021, 05:28 AM
  #34  
LarryFitch
Junior Member
Thread Starter
 
Join Date: Oct 2020
Location: West Richland, WA
Posts: 28
Likes: 0
Received 1 Like on 1 Post
Default

Al, Thanks for the good advice. I'll have to see how I can implement your recommendations into this build. The carbon tube over 4-40 steel rods is pretty standard on my builds as well. Not quite sure what to use for control rods yet, but being stiff is a requirement for sure. I doubt I will ever be flying the MoJoto it's limits. At 78 years, 3D is not in my normal routine--not for a long time, fingers are too slow.

Larry
Old 05-09-2021, 04:08 AM
  #35  
ahicks
My Feedback: (2)
 
Join Date: Aug 2008
Location: Waterford, Mi/Citrus Springs, Fl
Posts: 3,808
Received 14 Likes on 13 Posts
Default

Larry, I'm 70, but I've been flying forever. I think God invented slow 3D for guys like us. Lot's of stuff looks great and is just as challenging when flown in slow motion!

Old 05-10-2021, 06:27 AM
  #36  
daveopam
My Feedback: (9)
 
daveopam's Avatar
 
Join Date: Oct 2002
Location: ELK CITY, OK
Posts: 7,695
Received 21 Likes on 20 Posts
Default

Larry look at this and see if it's something you can use. I will tell you up front this glass gear is more spongy the ALUM and I don't think it's any lighter.

David



Old 05-10-2021, 07:51 AM
  #37  
LarryFitch
Junior Member
Thread Starter
 
Join Date: Oct 2020
Location: West Richland, WA
Posts: 28
Likes: 0
Received 1 Like on 1 Post
Default

David, I'm not too concerned with weight. Relative to "spongy" do you mean "springy". My general concerns with aluminum is that they tend to bend, getting wider and lower with use. Does this glass unit spring out of shape, getting wider, or just springier meaning more difficult to keep plane on the ground during landing. Not quite sure what issue I'm looking at? The measurments look about right for the MoJo 65, so I'm interested, if usable. I have zero experience with glass gear. Thanks for the info, and offer

Larry
Old 05-10-2021, 10:20 AM
  #38  
daveopam
My Feedback: (9)
 
daveopam's Avatar
 
Join Date: Oct 2002
Location: ELK CITY, OK
Posts: 7,695
Received 21 Likes on 20 Posts
Default

Larry to better explain myself re: spongy. The gear will start to get more flexible as time goes on and start to sag. Sometimes one leg more that the other. It's never caused me any landing issues and it sort of cushions the landing. The opposite of a CF gear where the gear is so stiff it's almost brittle. I hope that makes sense. I still think I have another set around someplace and I'm looking for it.
David
Old 05-10-2021, 01:18 PM
  #39  
scoeroo
My Feedback: (9)
 
scoeroo's Avatar
 
Join Date: Sep 2004
Location: Home PA
Posts: 610
Likes: 0
Received 2 Likes on 2 Posts
Default

I bought a set of these , way better than alloy gear
https://www.engelmt.de/mtaccessories...on-230x120-f3a
Old 05-11-2021, 04:56 AM
  #40  
ahicks
My Feedback: (2)
 
Join Date: Aug 2008
Location: Waterford, Mi/Citrus Springs, Fl
Posts: 3,808
Received 14 Likes on 13 Posts
Default

The thing I like about alum. is that they can be bent back into shape over and over again. I've never had an issue were they were straightened so many times they became weak or failed, but if I did, I'd just go up one size on the material dimensions I was using.

Too, the area of the fuse where the LG bolt holes are should be reinforced a bit to keep it from collapsing as the bolts are tightened - as well as from abuse (less than graceful landings). Soaking with thin CA works pretty good....

And for those that say you should learn how to land, landing something like this on it's tippy toes is pretty easy. It's the blown harriers (with 2' or less roll out) that are going to bend the gear..... -Al

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.