More main landing gear issues

Description of your first forum.
Post Reply
jchisolm
Posts: 111
Joined: Tue Jun 17, 2014 9:56 pm

More main landing gear issues

Post by jchisolm »

More gear woes...

I'm trying to fit the left gear and running into more issues I hope someone can shed some light on.

I have the aluminum gear legs from Grove. The drilled hole patterns match up but my problem is the fit to the gear clamp bracket. Either the gear leg is way to small or the bracket is way too large. The flat section of the gear (see pictures) measures 6" across but the inside size of the bracket, from clamp pin to clamp pin, is about 6.3". So I have about 150th on each side of the gear leg. The pressure pad plate is 6" in width so that seems to match up, but I don't have the rubber pressure pad.

I'm wondering if the clamp bracket Larry Olsen sent me a long time ago was really for the fiberglass gear legs by mistake.
Attachments
IMG_20200126_210414920_HDR.jpg
IMG_20200126_210403354_HDR.jpg
IMG_20200126_180045224.jpg
IMG_20200126_175755252.jpg
Joe Chisolm
Express CT builder
Marble Falls, Texas
jchisolm
Posts: 111
Joined: Tue Jun 17, 2014 9:56 pm

Re: More main landing gear issues

Post by jchisolm »

Update
I called Darrell at compair and left a message about getting new brackets. No reply yet. I figure I have 4 options:
1) New clamp brackets from compair if I can get them
2) build new clamp brackets myself that are 6 inches wide ID (not high on my list really)
3) Weld a 3/8 in thick plate to one of the existing bracket pins and mill down to correct width
4) Make new clamp bracket pins that are about 150th wider using some 3/8 plate and milling it down

Option 3 is possible. The current plate the pin is welded to is 1/8 (.125) and I need +300th added. I could weld a 3/8 plate to the .125 plate trial fit and mill the face until I get a snug fit. If I put the wider pin in the aft hole the gear forward face will be in the proper position but I'll have about a 3/8 space (filled by the larger plate width) on the aft side. I'm not sure if this would cause some flexing problems with the bracket (the oval 2 piece part). Also the aft pressure plate bolt will be very close to the end of the pressure plate.
The other possibility is to put the wider pin in the front but this would move the gear aft by about 3/8 and still might have the same flex problem.

Option 4 is possible and easy. Build 2 new pins welded to 3/8 in thick flat bar. To center the gear in the larger opening I need about .275 on each side. So I could mill about 100th off the 3/8 plates. The issue is that puts the gear about 3/16 aft of it's correct forward position. The plus side is I dont have the asymmetrical load on the clamp bracket.

I have lots of other things to work on so I can wait to hear from compair.

Thoughts / comments appreciated.
Joe Chisolm
Express CT builder
Marble Falls, Texas
phil_thomas
Posts: 24
Joined: Fri Mar 23, 2018 5:25 pm
Location: Nashville, TN

Re: More main landing gear issues

Post by phil_thomas »

Joe,

If the weather is good this weekend I'm planning on going to the airport to fly. I have the aluminum gear on my Express so while there I'll take a pic of the bracket on mine to see how it compares to what you have.
Phil Thomas
Nashville, TN
jchisolm
Posts: 111
Joined: Tue Jun 17, 2014 9:56 pm

Re: More main landing gear issues

Post by jchisolm »

Hope the weather holds and you get some quality "express time"
My Cherokee is kind of grounded right now until I get the SkyBeacon installed. Weather is supposed to be nice here also so I'm hoping to get to the airport and get that taken care of.
Joe Chisolm
Express CT builder
Marble Falls, Texas
phil_thomas
Posts: 24
Joined: Fri Mar 23, 2018 5:25 pm
Location: Nashville, TN

Re: More main landing gear issues

Post by phil_thomas »

Sorry, Joe, today was the first day I've been back to the airport to get pics for you. We have the aluminum gear and our brackets don't have the space on the side as yours do. Hope this helps you.
IMG_0767.jpg
IMG_0768.jpg
Phil Thomas
Nashville, TN
jchisolm
Posts: 111
Joined: Tue Jun 17, 2014 9:56 pm

Re: More main landing gear issues

Post by jchisolm »

Thanks
That confirms my thoughts that these brackets are really for the fiberglass gear or they were just made wrong. I looked back through my invoices and I see I got the brackets from Larry Olson (EDI) but I got the actual gear legs directly from Grove.
I made some new pins that go in the sides of the bracket. I used some 3/8" flat steel. Now I need to mill the face of each side down some for a snug fit to the gear leg. I also called Grove and got one pair of their radius blocks. I'm investigating what it will take to replace the current bracket, clamp and pins. The Grove radius block is a very clean install. No clamp and rubber pads. The gear fits in the radius blocks and the blocks bolt to the aircraft structure. Of course you still have the Rib J attachment. I still have to come up with a way to attach the radius block to Rib R, working through the math and the loads.

It may be easier, and would be faster, to just stay with the current bracket, clamps and pressure pad setup.
Joe Chisolm
Express CT builder
Marble Falls, Texas
Post Reply