Center Section - Snap Bushing?

[skelrad]

Long, long ago when I put together the center section bulkhead, I ground down the side of a plastic snap bushing so it would fit in the wiring hole that is on the outside portion of the bulkhead (ground down because part of the hole gets encroached on by the vertical 904D piece). Fast forward to today as I'm finishing up my wiring runs. Now with the landing gear in place (9A), a snap bushing won't fit in the hole because of the combined thickness of all the parts. Do I just need to look for snap bushings that can accommodate deeper material, or are there other options for a hole like this?

 

[cvairwerks]

MS21266 alligator edge....Cut and trim as needed and then Scotch Weld to the hole. For easy application of the Scotch Weld, mix as usual and then spoon into a sandwich bag corner. Twist up like a pastry bag and snip the corner. Squeeze and apply to the run between the teeth. Place into position and push til the center is against the edge of the hole.

M22529 is identical, but has a lower temp rating than the MS version.

 

[PaulvS]

Rubber wiring grommets are available in various groove widths and diameters, e.g.

AN931 Elastic Grommets | Aircraft Spruce

AN931 Elastic Grommets Flexible grommets, made of black synthetic rubber to specification MIL-G-3036. Resistant to hot oil & coolant. Used to protect tubing, wiring and control cables where they pass through bulkheads & fir...

www.aircraftspruce.com

 

[BoydBirchler]

I got a whole kit of rubber grommets at Harbor Freight & Tool... Not much money.

 

[wirejock]

McMaster will have them.

 

[skelrad]

Thanks all!

 

[dmn056]

MS21266 alligator edge....Cut and trim as needed and then Scotch Weld to the hole. For easy application of the Scotch Weld, mix as usual and then spoon into a sandwich bag corner. Twist up like a pastry bag and snip the corner. Squeeze and apply to the run between the teeth. Place into position and push til the center is against the edge of the hole.

M22529 is identical, but has a lower temp rating than the MS version.

Also sometimes referred to as "tram track", but I think you've got the temperatures back to front. From the manufacturer's web site:

Spring-Fast Grommet Edging

M22529 is rated at a slightly higher temperature. However, the main difference is the geometry, and the fact that M22529/1 has spring loaded teeth and does not require adhesive for installation.

 

[cvairwerks]

MS21266 TFE is rated for 275C, MS21266 Nylon is rated for 125C, while M22529/1 is rated for 145C and M22529/2 is rated for 85C continuous ambient temps. Depends on which material you get, as to the rating. Data is per Table 6, of MIL-DTL-22529 Rev D.

Don't think anyone is going to see temps over 85C in their cockpit, unless things are going bad in a hurry, and in that case, it probably won't matter to anyone but the investigators.

We strictly use MS21266 TFE at work, as we can't rely on the springiness of the edging to stay in place under all conditions.

 

[JonJay]

All go ideas above.
Heyco makes snap bushings in all kinds of configurations including “shorty”, split, and many others. They have a great website.
If that hole is for a moving rudder cable, you will want a hard plastic bushing. These hold up well to rudder cable wear over the years.