VansAirForceForums  
Home > VansAirForceForums

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

- Today's Posts | Insert Pics

  #21  
Old 07-09-2015, 06:38 PM
Mike S's Avatar
Mike S Mike S is offline
Senior Curmudgeon
 
Join Date: Sep 2005
Location: Dayton Airpark, NV A34
Posts: 14,172
Default

Quote:
Originally Posted by maus92 View Post
I was thinking about cutting a 3/16 steel rod to size and threading the ends - has anyone done this?
I recall someone doing something like this, but cross drilled the rod, used a washer or two and cotter pins.
__________________
Mike Starkey
VAF 909

Rv-10, N210LM.

Flying as of 12/4/2010

Phase 1 done, 2/4/2011

Sold after 240+ wonderful hours of flight.

"Flying the airplane is more important than radioing your plight to a person on the ground incapable of understanding or doing anything about it."
Reply With Quote
  #22  
Old 08-10-2018, 07:21 AM
tgmillso tgmillso is offline
 
Join Date: Nov 2012
Location: Launceston, Tasmania, Australia
Posts: 597
Default Increased spring force

After a recent post in another thread from someone asking about brake return spring mods, I thought I should finally update this thread with my brake modifications. I assembled my Matco master pistons with the springs recommended in this thread and there was only a barely perceptible increase in return force. I subsequently took some measurements of the spring force in the matco's, ran a few calcs, and came up with an alternative spring solution that will double the current spring force. The original spring upgrade was a maximum of 6lb in compression. This one is 30lb. I've tested them out over the past week during my taxi tests and they feel perfect, with no risk of dragging brake, even if your toes are naturally leaning on the pedals, but not too much force that they become an incomberance when you want the brakes. I also modified the collar sleeve arrangement so that even at full brake compression, there is no way that the spring can rub on the ram. The sliding collar is also a self lubricating polymer, which should help with longevity. Just make sure when you assemble things that the collar is low enough to just clear the top mounting tab, but not so low that you restrict compression of the ram. My aircraft is an RV-7, and I would absolutely recommend the long-bolt (single axis) mod to the brake pedal to eliminate binding, in addition to the spring upgrade. You'll also see in the photos some another mod I did to make some standoffs. These are just aluminum split collars and a piece of tubing cut into thirds, then riveted in place with some long AN470AD4 rivets (the collars are countersunk on the inside and I back riveted it against an appropriate diameter bolt shank). I've also stacked two more short pieces of the cut tubing in between to give myself a little further distance.
Anyway the McMaster Carr parts list is as follows.
Spring 9657K435
Lower nylon sleeve bearing: 6294K441
washers (for seating the lower nylon sleeve bearing) 90295A470
Top nylon sleeve bearing: 6389K625
Set screw shaft collar: 9946K13

For the standoffs:
Two piece collar: 6436K136
Aluminum tubing: 9056K79

Hope this helps.
Tom.



Reply With Quote
  #23  
Old 08-10-2018, 08:16 PM
longranger's Avatar
longranger longranger is offline
 
Join Date: Mar 2007
Location: 45G, Brighton, MI
Posts: 1,789
Default

Quote:
Originally Posted by Mike S View Post
Quote:
Originally Posted by maus92 View Post
... I was thinking about cutting a 3/16 steel rod to size and threading the ends - has anyone done this? Should I sleeve the rod within the pedal face?
I recall someone doing something like this, but cross drilled the rod, used a washer or two and cotter pins.
Now I remember why I ordered that piece of 3/16 4130 steel rod... Im planning on the washer and cotter pin route.
__________________
Miles (VAF# 1238, Paid up as of 2018)
RV-7 TU 904KM (reserved)
Wings Fitted and Finish Kit on order

Construction Log
Picasa: Empennage Album, Wings Album, Fuselage Album

1955 Cessna 170B flying since 1982

'To get something you never had, you have to do something you never did.' -Unk.
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 06:26 PM.


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.