VansAirForceForums  
Home > VansAirForceForums

- POSTING RULES
- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics

  #31  
Old 08-21-2011, 11:07 PM
PaulT PaulT is offline
 
Join Date: Aug 2011
Location: South Australia
Posts: 66
Default

Hi, I,m kind of new here although I have often refered to the Forum when I needed to see how others did something which has helped during my RV-8 build. (kudos to you Dan aswell as many others). This thread spurred me into registering and I hope it keeps going a bit.

I have just gone through the initial mounting/aligning/drilling of my stock gear legs (not a satisfying experience). My stock gear could not possibly be aligned as described, and have had to accept some comprimise. Many have described difficulty in this area. My problem seems to stem from the bend in the leg near the outboard bracket, it seems as though one leg angles slightly aft and the other fwd when viewed from the side. Also the R/H leg is about 40 thou thicker than the left (poor QC ?). I wonder if Vans should consider using Grove as the supplier of Gear for the -8.

I think you pretty much nailed it in your #9 post Dan. To me the design in this area, particularly the layout of the 802K and L crossmembrs almost makes it look as though it was always the intention to have a One piece setup, with the F-802M intercostals added just to support that part of the f-850 skin.This gear certainly ticks a lot of boxes. They probably went Two piece to save some wieght with the steel gear. (Not a consideration with the ally considering the benefits) Just a few minor workarounds with cover plates and ventlines etc.

I have recently been in touch with Gail from Grove about shipping Airfoil Gear, Wheels and brakes to Aus' although at that time I had no idea a One piece Airfoil U/C was available. I/ll be sending another email to her shortly as it's not to late for me to change. Anyone need some high quality stock gear legs.

Paul
__________________
RV-8 FB, S l o w Build,
180FI, Catto,
Australia.
Reply With Quote
  #32  
Old 08-23-2011, 11:33 AM
scsmith scsmith is offline
 
Join Date: Jan 2008
Location: Ashland, OR
Posts: 2,574
Default intercostal floor ribs

Hi all, sorry I was away for a few days and missed Dan's question.

Reviewing the drawings, I don't see any issue at all with trimming the intercostal ribs down as pictured.

In monocoque structures, ribs are used to maintain cross sectional shape, transfer localized loads into the main structural elements (spars or longerons) and prevent skin buckling (which is kind of the same thing as maintaining cross section

In this case, they are mostly providing local skin support to prevent buckling and support the floor locally from loads. They are working in concert with the triangular floor ribs to form shear webs that make the floor stiff in bending from loads applied in the middle of the floor. Its pretty far forward so not really possible to stand on that part of the floor, so I'm not at all worried about loads.

The trimmed down rib, as pictured, is still providing a bit of skin stiffening which should be enough for all but some peak bending load like a hard landing. In that case, the longerons pick up the loads so its OK if the skin flexes a bit. It would be good to leave as much of a raised edge from the original rib as possible while still avoiding contact with the gear which may still flex some (much less than a 2-point supported gear, as discussed earlier)

I would also try to put some kind of doublers at the same places in the outer skin/cover plate that you will make to cover over the trench that the gear sits in. These could be internal if there is room, or external.

Nice work -- If I build another one, I might do this too.
__________________
Steve Smith
Aeronautical Engineer
RV-8 N825RV
IO-360 A1A
WW 200RV
"The Magic Carpet"
Hobbs 625
LS6-15/18W sailplane SOLD
bought my old LS6-A back!!
VAF donation Jan 2020

Last edited by scsmith : 08-23-2011 at 11:37 AM.
Reply With Quote
  #33  
Old 08-23-2011, 12:19 PM
Guenthfa Guenthfa is offline
 
Join Date: Sep 2007
Location: Chehalis, WA
Posts: 28
Default Grove Gear

I had the one piece gun drilled grove gear on my One Design and thought it was the cats a$$. I had the pleasure of watching him go though the process of making it. For gun drilling the brake line passages they use a cool looking old machine tool made by the Browning company to drill machine gun barrels.

Fritz
Reply With Quote
  #34  
Old 09-01-2011, 12:15 PM
Roo747's Avatar
Roo747 Roo747 is offline
 
Join Date: Aug 2010
Location: Flesherton, ON
Posts: 33
Default latest from Grove

Hey Guys,

Just got this reply from Gail regarding the one piece.

Andrew,

If we get 10 people to order will can make them, they would be air foiled.
As of right now we have ZERO people that have ordered.
I don't believe that we will be building any time soon.


Thank You,

Gail Austin
Grove Aircraft LGS Inc.
1800 Joe Crosson Drive
El Cajon CA 92020
619-562-1268
www.groveaircraft.com
gail@groveaircraft.com
Reply With Quote
  #35  
Old 09-02-2011, 06:14 AM
PaulT PaulT is offline
 
Join Date: Aug 2011
Location: South Australia
Posts: 66
Default

I got much the same story from Gail.

They really want people to commit to buy first, but still no word on pricing.
They say they have no such commitments or deposits at the moment. (as Andrew mentioned)

Personally I think, If they build it, they will come. If they were to do a run of ten, I reckon they will go in no time.

They are (still) doing non Airfoil one piece. "one piece RV8 gear that is available un airfoiled".

I'm thinking about doing the before mentioned cover plate mod over the F-802K/L just in case they do become available soon (at a reasonable price).
My Grove wheels/Brakes are ordered.

Paul
__________________
RV-8 FB, S l o w Build,
180FI, Catto,
Australia.

Last edited by PaulT : 09-02-2011 at 06:16 AM.
Reply With Quote
  #36  
Old 09-02-2011, 06:44 AM
DanH's Avatar
DanH DanH is online now
 
Join Date: Oct 2005
Location: 08A
Posts: 9,500
Default

I suspect there are quite a few builders watching this thread as we explore the structure. Nail it all down and the orders will come. I might point out that Steve and I already have wheels under flying airplanes. Anybody in a hurry?
__________________
Dan Horton
RV-8 SS
Barrett IO-390
Reply With Quote
  #37  
Old 09-02-2011, 06:48 AM
humptybump humptybump is offline
 
Join Date: Feb 2011
Location: USA
Posts: 3,179
Default

Dan, I'm already flying. I'd be interested in your thoughts if this is a good retrofit option and if so (or not), what conditions should be consider?

Thanks,
Reply With Quote
  #38  
Old 09-02-2011, 06:49 AM
hendrik hendrik is offline
 
Join Date: Nov 2009
Location: Heidelberg, Germany
Posts: 182
Default

Quote:
Originally Posted by DanH View Post
I suspect there are quite a few builders watching this thread as we explore the structure.
Me for example , but I'm still far away from ordering the fuse.
__________________
Hendrik
Club-Libelle: flying
RV-8: on hold (new job , new home , no workshop (yet) )
Reply With Quote
  #39  
Old 09-02-2011, 07:07 AM
PaulT PaulT is offline
 
Join Date: Aug 2011
Location: South Australia
Posts: 66
Default

Over 4,600 views at this point.
Should we direct Grove to this thread?, they may even like to comment.
I am right at this point in my build. I,m in more of a hurry to finish the RV now. My 140 failed a crank insp.
Also getting quote for shipping to Oz for the SP FB/Cowl.
__________________
RV-8 FB, S l o w Build,
180FI, Catto,
Australia.

Last edited by PaulT : 09-02-2011 at 07:19 AM.
Reply With Quote
  #40  
Old 09-21-2011, 10:14 AM
DanH's Avatar
DanH DanH is online now
 
Join Date: Oct 2005
Location: 08A
Posts: 9,500
Default

Sorry about the delay. The time has been spent with some some private discussion of failure modes and structural details.

It would appear the best bet remains a constant-section crossmember, much like the one in post 24. The U806 inboard wear plate and its AN4 attach hardware would be retained. The U804 clamp bracket would be deleted. The single inboard AN7 bolt would get a hardened washer under the head.



Use of the inboard bolt is a minor change from previous one-piece gear for the RV8. If Grove is to drill those holes they will need the hole-to-hole dimension across the belly.

Someone should look at the optimum placement of the brake fluid passage.

The forward section of the F850-1 belly skin would be removed and re-tasked as a center cover plate. The best method of attaching it remains to be determined. I'd suggest flush blind rivets.

No detailed structural model was developed or analyzed, and no one can offer any perfect assurance of less fuselage damage or better performance in a groundloop. Given a significant twirl you'll still get wingtip damage. There does not appear to be any way the one-piece gear would make things worse, which satisfies the first rule of modification. It would be heavier than a two-piece Grove, but remain lighter than the stock steel gear. If I was building another -8 it would have one-piece aluminum gear.

The Grove request for 10 orders is nothing new. Best I know the two-piece airfoil gear has always been made in batches. You place your order, others place theirs, and when they get enough in the pile they run off a batch. If you want it, order it.

Airfoil or plain? Plain is 6 lbs lighter and costs less. Think hard about it.
__________________
Dan Horton
RV-8 SS
Barrett IO-390
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 07:13 AM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.