Go Back  RCU Forums > RC Airplanes > RC Jets
Reload this Page >

BVM Composite Bandit Build Thread. Yes from 1998.

Notices
RC Jets Discuss RC jets in this forum plus rc turbines and ducted fan power systems

BVM Composite Bandit Build Thread. Yes from 1998.

Old 02-20-2018, 11:28 AM
  #101  
mr_matt
My Feedback: (10)
 
mr_matt's Avatar
 
Join Date: Dec 2001
Location: Oak Park, CA,
Posts: 10,446
Likes: 0
Received 12 Likes on 10 Posts
Default

Yes the toothpick deal is the same as those F-4 cowls. I built a BVM f-4 and it had those same gaps. Just make sure you get plenty of glue on there.
Old 02-20-2018, 02:58 PM
  #102  
roger.alli
 
roger.alli's Avatar
 
Join Date: Aug 2008
Location: Sydney NSW , AUSTRALIA
Posts: 1,016
Received 1 Like on 1 Post
Default

Here is a tip with the toothpick method.

-Line the parts up perfectly and tape firmly in place from the inside.
-Start gluing on toothpicks from the top.
-Using medium cyno (sparingly) and kicker, glue the first tooth pick to the cowl side only. Don’t put any glue on the fuse side, or get any cyno in the gap.
-Cyno the second tooth pick to the fuse side only. Don’t glue it to the cowl.
-Work down form the top, gluing them on alternately, fuse, then cowl. Space them about 10 mm apart and work right around to the underside.
-When finished, remove the tape you used to hold the parts in place..
-Now, CAREFULLY, slide the cowl forward and off the fuse,,, with half the toothpicks still attached to each side!!
You should be able to slide it back into place with it lining up perfectly. You are now ready to apply Hysol.

The photo below is my crappy photo shop of how it will look.

I actually glue the tooth picks directly on to the surface, with no protective masking tape. It is fairly easy to remove them and refinish the surface. You will need to do some filling in this area anyway.

As Matt says, make sure you get plenty of Hysol into the seam, when you finally glue in place. It should ooze out a little bit.

Keep us posted..
Attached Thumbnails Click image for larger version

Name:	Vert Seam.jpg
Views:	157
Size:	109.1 KB
ID:	2255378  

Last edited by roger.alli; 02-20-2018 at 09:19 PM.
Old 02-21-2018, 08:28 PM
  #103  
essyou35
Thread Starter
My Feedback: (11)
 
Join Date: Dec 2009
Location: Central Midwest
Posts: 1,946
Received 25 Likes on 22 Posts
Default

Trying to get a pic of this is touch. But as I push my cown onto the fuse, its like the cowl is too big to fit into the fuse seem. There is a good .5mm of slack or so. So if I start bottom or top and line it up exactly with the fuse seem, when I get to the end there is a gap because its too "long". I tried sanding lots but its as thin as its going to get, any ideas what I need to do?

The toothpick method works ok if I use balsa, it allows the slack to spread out a bit but makes an uneven seem. Toothpicks have a bit much give, so the balsa is better. But getting hysol in the fuse underneath the balsa seems to be a chore! Also once I glue it some glue will come out and get on the balsa and the balsa will be fused to the seem. I assume I just sand that out?

Somethings off here.
Old 02-21-2018, 09:25 PM
  #104  
dubd
 
dubd's Avatar
 
Join Date: Aug 2007
Location: Bay Area, CA
Posts: 4,313
Likes: 0
Received 2 Likes on 2 Posts
Default

What is a “aileron trainer”?
Old 02-21-2018, 09:55 PM
  #105  
mr_matt
My Feedback: (10)
 
mr_matt's Avatar
 
Join Date: Dec 2001
Location: Oak Park, CA,
Posts: 10,446
Likes: 0
Received 12 Likes on 10 Posts
Default

Yes the bottom line is the cowl is a bit too big for the fuse. The whole reason you are using the balsa sticks is to try to distribute the cowl gap as evenly as possible over the whole perimeter. If you have a perfect gap somewhere, you will have a huge gap somewhere else. So the balsa sticks just make it easy to have a constant gap.

You don't care how much glue oozes out as you are going to sand it off. I recommend the old classic aeropoxy, loctite 9462. It sands pretty well. Fill up the gap 100% or you will have sanding waves later.

After sanding down the glue, you will have a new challenge, you will have to level out that seam, using a polyester filter (lightweight Bondo), or an epoxy filler I prefer. A lot of work left after those cowls are on.
Old 02-22-2018, 02:10 PM
  #106  
essyou35
Thread Starter
My Feedback: (11)
 
Join Date: Dec 2009
Location: Central Midwest
Posts: 1,946
Received 25 Likes on 22 Posts
Default

Well then lol, I guess I didnt follow fully what was going on. Honestly, I keep thinking this is BVM, they are perfect and it must be something I am doing wrong.
On the inside, once you glue, are you sanding down the flanges/mating surfaces flat? I thought that is what you were talking about sanding.
Old 02-22-2018, 02:49 PM
  #107  
mr_matt
My Feedback: (10)
 
mr_matt's Avatar
 
Join Date: Dec 2001
Location: Oak Park, CA,
Posts: 10,446
Likes: 0
Received 12 Likes on 10 Posts
Default

Well yes, you have to sand the outside, but you also will use filler to level it out (fill, sand, repeat, fill sand, repeat). The outside will get sanded down flat at least 320 grit before the primer goes on.

The inside sanding is just to get it flat enough to glass in the reinforcing cloth reasonably flat.

In my experience this kit is about as good as fiberglass kits came, maybe Jet Model was a bit better, Yellow a bit behind but close. This is just stuff you have to do to build a fiberglass kit, nothing unusual. It all depends how good you want it to come out. I know one thing you can make it a hell of a lot better than the ARFs out there.

Last edited by mr_matt; 02-22-2018 at 02:52 PM.
Old 02-22-2018, 03:24 PM
  #108  
roger.alli
 
roger.alli's Avatar
 
Join Date: Aug 2008
Location: Sydney NSW , AUSTRALIA
Posts: 1,016
Received 1 Like on 1 Post
Default

Yeah, What Matt Said.

Fibreglass is not a completely “stable” product and it will deform over time. Plus Sizing is never 100 % accurate or consistent, these parts were are hand laid. And sometimes it seems as if the BVM kit designers went out of their way to make a job difficult. (Wait till you try hinging a Super Bandit.)

Remember, your kit is 20 years old and model jet construction has evolved an awful lot since then. In 1998 The Comp Bandit was the absolute top of the tree, aimed at the very best builders and flyers in the Country (all flyers were builders in 1998).
Today, you can buy a Bandit PnP. No glue required .

Keep at it. You will learn so much from building this model, and the end result will be so much more satisfying..
Old 02-22-2018, 05:50 PM
  #109  
essyou35
Thread Starter
My Feedback: (11)
 
Join Date: Dec 2009
Location: Central Midwest
Posts: 1,946
Received 25 Likes on 22 Posts
Default

Hey Roger I completely understand, I wasnt trying to complain. I just assumed I was doing something wrong.

Now a days, if someone has to glue something onto an arf or "sand it to fit" they want a refund.
Old 02-22-2018, 06:42 PM
  #110  
essyou35
Thread Starter
My Feedback: (11)
 
Join Date: Dec 2009
Location: Central Midwest
Posts: 1,946
Received 25 Likes on 22 Posts
Default

One down. Lots of glue underneath but probably will have ripples when I sand.
I have plenty of tamiya putty on hand.
Attached Thumbnails Click image for larger version

Name:	20180222_203607.jpg
Views:	170
Size:	1.49 MB
ID:	2255610   Click image for larger version

Name:	20180222_203622.jpg
Views:	202
Size:	1.48 MB
ID:	2255611  
Old 02-22-2018, 06:59 PM
  #111  
mr_matt
My Feedback: (10)
 
mr_matt's Avatar
 
Join Date: Dec 2001
Location: Oak Park, CA,
Posts: 10,446
Likes: 0
Received 12 Likes on 10 Posts
Default

That looks good,

You are going to need some sort of lightweight bondo type material, like evercoat (catalyzed polyester filler) or some epoxy, I use this:

SUPER FIL from Aircraft Spruce

That Tamiya putty is probably lacquer based, it will be difficult to lay enough of it down for what you will be doing (shrinking, drying, etc.) It is good for pinholes or really small dings but the big stuff you need something that wont shrink. In my opinion
Old 02-22-2018, 08:08 PM
  #112  
roger.alli
 
roger.alli's Avatar
 
Join Date: Aug 2008
Location: Sydney NSW , AUSTRALIA
Posts: 1,016
Received 1 Like on 1 Post
Default

Looks great!!

The inlet/cowl fit step is maybe the toughest part of the build.

+ 1 on the 2 part filler. I use an automotive finishing polyester filler. it is strong and easy to work, but quite heavy. That product Matt recommends looks interesting.
Old 02-23-2018, 09:51 AM
  #113  
essyou35
Thread Starter
My Feedback: (11)
 
Join Date: Dec 2009
Location: Central Midwest
Posts: 1,946
Received 25 Likes on 22 Posts
Default

What do you guys think of the fillers from west?
http://www.dreamworksrc.com/catalog/...Systems?page=1

They have a microlight used for filling only, and a low density that is for bonding and filling. Im getting ready to order the Itrap 40ml for this jet though I would throw one of those in the cart.

I also have west epoxy and microballons or milled fiberglass. Is there a reason I need to use a bondo type substance? Typically Ill use spackle on these and hit it with CA or 20min epoxy laminate to fill the pinholes.

Last edited by essyou35; 02-23-2018 at 09:54 AM.
Old 02-23-2018, 10:54 AM
  #114  
mr_matt
My Feedback: (10)
 
mr_matt's Avatar
 
Join Date: Dec 2001
Location: Oak Park, CA,
Posts: 10,446
Likes: 0
Received 12 Likes on 10 Posts
Default

Whatever you think will work, I have never tried thickening epoxy that much, don't see why it would not work.

You have to be able to sand and feather it, that is the key. The edge has to feather into that gel coat you have (I think your kit is so old it still has gel coat and not the grey K-36 primer they used later.
Old 02-23-2018, 11:01 AM
  #115  
essyou35
Thread Starter
My Feedback: (11)
 
Join Date: Dec 2009
Location: Central Midwest
Posts: 1,946
Received 25 Likes on 22 Posts
Default

Hmm, I know the wings and surfaces are primer.. but now that Im thinking about it not sure on the fuse. It is a different color than the surfaces for some reason.
Im going to give that filler a try from west, the low density. Its cheap enough.
Old 02-23-2018, 07:27 PM
  #116  
ravill
My Feedback: (11)
 
ravill's Avatar
 
Join Date: Jan 2003
Location: Granite Bay, Ca
Posts: 5,704
Received 90 Likes on 72 Posts
Default

Wow, great job man!

And I complain from building the BARF's!

BV's "ARF's" I've always said should be classified as being "AARF's". I.e., Almost ready to be Almost Ready to Fly.
Old 02-25-2018, 02:55 PM
  #117  
roger.alli
 
roger.alli's Avatar
 
Join Date: Aug 2008
Location: Sydney NSW , AUSTRALIA
Posts: 1,016
Received 1 Like on 1 Post
Default

I have never seen the West System fillers before. You guys in North America seem to have access to a lot more products than we do down here. . One reason I like the polyester auto fillers is because it cures very quickly, can be rough cut while green (withing minutes), and is real nice to sand.. I use Taymia filler for pin holes.. It is worth experimenting with fillers. Everyone seems to have a favorite brand and method.

I think your fuse is finished in primer.. My Classic Bandit was..

When are you ordering that Super Bandit Raff ?
Old 02-25-2018, 03:27 PM
  #118  
essyou35
Thread Starter
My Feedback: (11)
 
Join Date: Dec 2009
Location: Central Midwest
Posts: 1,946
Received 25 Likes on 22 Posts
Default Intake cracks

Where do the intakes crack at when flown hard. Im making good progress and getting ready to lay down some glass, but want to ensure I get the right areas.
Old 02-25-2018, 04:31 PM
  #119  
mr_matt
My Feedback: (10)
 
mr_matt's Avatar
 
Join Date: Dec 2001
Location: Oak Park, CA,
Posts: 10,446
Likes: 0
Received 12 Likes on 10 Posts
Default

Right over the joint on the inside, maybe 1.5 inches off of the center on either side of the joint. But you have to make the joint flat enough so that you can still get the tanks in. You can always glass it later after you get the inlets in if you are worried about fitting the tanks
Old 02-25-2018, 06:07 PM
  #120  
essyou35
Thread Starter
My Feedback: (11)
 
Join Date: Dec 2009
Location: Central Midwest
Posts: 1,946
Received 25 Likes on 22 Posts
Default

For the outside I didnt have too much to fill, thanks to the good advice of using tons of hysol in there. I just tamiya putty for now.

Attached are some pics of the result. I sanded out the 90 degree lip on the inside of the fuse where the cowls mate up. Am I supposed to sand anything else? I got the bottom joint sanded well but not sure how much it needs to be sanded down. I plan to put some thick glass across these joins as far forward into the intake cows as I can get.
Attached Thumbnails Click image for larger version

Name:	FILE0014.JPG
Views:	133
Size:	859.7 KB
ID:	2256117   Click image for larger version

Name:	FILE0015.JPG
Views:	121
Size:	858.9 KB
ID:	2256118   Click image for larger version

Name:	FILE0016.JPG
Views:	120
Size:	634.1 KB
ID:	2256119  
Old 02-25-2018, 06:32 PM
  #121  
mr_matt
My Feedback: (10)
 
mr_matt's Avatar
 
Join Date: Dec 2001
Location: Oak Park, CA,
Posts: 10,446
Likes: 0
Received 12 Likes on 10 Posts
Default

Super job. Looks great. It looks flat enough to me. Maybe mock up the inlets now and see how the tanks fit to give you an idea of how much glass you can add
Old 02-25-2018, 06:57 PM
  #122  
roger.alli
 
roger.alli's Avatar
 
Join Date: Aug 2008
Location: Sydney NSW , AUSTRALIA
Posts: 1,016
Received 1 Like on 1 Post
Default

That is looking great.. Some minor filling then sanding with a flat block, and that joint seam will be invisible.
Old 02-27-2018, 01:15 AM
  #123  
tisdall_80
 
Join Date: Aug 2008
Location: Brisbane, AUSTRALIA
Posts: 215
Likes: 0
Received 1 Like on 1 Post
Default

Awesome to see building threads.. Give me motivation to build and not go down the ARF path.. I have a BVM Super Balsa Bandit sitting there.. Hmm one day..
Old 02-28-2018, 08:17 PM
  #124  
essyou35
Thread Starter
My Feedback: (11)
 
Join Date: Dec 2009
Location: Central Midwest
Posts: 1,946
Received 25 Likes on 22 Posts
Default

Question for the day. When installed, should there be a gap between the inlets and the fuse, or are the inlets supposed to be glued to the side of the fuse? With this gap, there is a small gap on the opposite side with the cowl. If I glue the inlet to the side of the fuse, Ill have to cut an area out of the splitter plate to slide into. Right now the splutter plate will slide in the gap and the cowl has the area cut out for it.
Attached Thumbnails Click image for larger version

Name:	FILE0019.JPG
Views:	105
Size:	722.0 KB
ID:	2256520  
Old 03-01-2018, 08:24 AM
  #125  
mr_matt
My Feedback: (10)
 
mr_matt's Avatar
 
Join Date: Dec 2001
Location: Oak Park, CA,
Posts: 10,446
Likes: 0
Received 12 Likes on 10 Posts
Default

I am not sure I get your question, but no that gap in the picture should not be there. Test fit the splitter before you do anything else. All you really care about is the fit of the outboard surfaces of the splitter and the inlets. Who care what is going on behind it, you can just shim it.

BTW, I did not glue the splitter on. Easier to take it off for painting.

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.