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Proper sized Adel clamps for firewall forward.

ERJDriver

Well Known Member
Engine is off getting an IRAN and id like to clean up the wiring on the engine mount.

Anyone have part numbers for the proper sized clamps for the engine mount to secure everything?
 
Engine is off getting an IRAN and id like to clean up the wiring on the engine mount.

Anyone have part numbers for the proper sized clamps for the engine mount to secure everything?
I don't have an RV8 but the engine mount tubes likely aren't all the same size. Rather than asking on here for a one size fits all answer, it's probably better to just measure and order as appropriate.

The last 2 digits in the part number is the diameter in 1/16".
 
I don't have an RV8 but the engine mount tubes likely aren't all the same size. Rather than asking on here for a one size fits all answer, it's probably better to just measure and order as appropriate.

The last 2 digits in the part number is the diameter in 1/16".
10 4, tubes are 3/4 and slightly bigger. Thanks
 
The engine mount tubes are either 3/4" diameter (on all the straight tube runs) or 7/8" diameter (on the curved runs between the engine shock mounts). This means you need MS21919DG (non-wedge) or MS21919WDG (wedge type) -12 and -14 size clamps. The WDG type have the wedge as mentioned in an earlier post.

If your wiring runs are like mine you will need a LOT of -12 clamps to attach to the 3/4" engine mount tubes (25 or so?), and fewer -14 to attach to the 7/8" engine mount tubes (8-10?). As for what you need to attach the wire bundles, hoses, tubes, and whatever else hangs off an engine mount clamp.....you're on your own. I ended up with a starting order of 10x of every size from -2 to -11, in addition to the -12 and -14 sizes mentioned above. In some cases my starting order wasn't enough for some sizes. Many of them were used on the engine, some in other parts of the airframe. YMMV.
 
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Suggest you purchase an adel clamp tool as well, if you don't already have one. This was a great addition to the tool kit and reduced the time and frustration for me. 0.020" safety wire works too, but I always puncture a finger or two using this method..

 
Thank you all. Guy that built it used all zip ties. Time to clean her up!
Properly installed, zip ties are lighter, cheaper, far easier to install, easier to make changes and take up less space.

Pull ties are not for everything. When used for wires that run along the motor mount and along the pan, they do a god job
of holding and keeping wires out of the way.

I have pull ties in service for over 18 years on my motor and not one failure.
 
Thank you all. Guy that built it used all zip ties. Time to clean her up!
Just a few things;

-there's nothing wrong with zip ties as long as you use quality nylon ones. The cheap ones from harbor freight or the big box store typically aren't nylon and will turn brittle with heat.

- If zip ties are used on engine mounts, they really should have a protective layer under them. If they're attached directly to an engine mount tube without something under them, then dirt and grit can get in there and over time they will cut a groove into the engine mount. Something like silicone tape works well in this application, but you need to have a plan to inspect during your condition inspection to make sure moisture isn't getting under there.

'-In my opinion, if you use adel clamps on the engine mount, they really should be the white high temp ones. The black ones will degrade over time with exposure to the kind of heat you see in that environment. That may or may not be a big deal in some applications. (Lycoming ships their engines with black ones on the top of the engine supporting the fuel injection lines so they obviously have no problem with it).

On my plane I changed the fuel injection ones out for white ones as well as all the ones I used to butterfly stuff to the engine mount. I reasoned that if the cushion turns the consistency of a hockey puck you could potentially start to see the same kind of abrasion issues over time that you do with zip ties and I didn't want to have to worry about it.

- you could also go with the nuclear option; There are blue silicone ones, which are impervious to both heat and chemical degradation. So no worries if you spill oil on them during an oil change or whatever, but they're pretty expensive and in my opinion, overkill for most locations.
 
You need the heat resistant Adele firewall forward. I prefer MS21919WCJ
They are fuel and heat resistant.
Geez Larry- those things are anywhere between 2 and 15 bucks a pop for the common sizes. I stand by my opinion that they're overkill for most of what we're doing, but you're going to have one of the nicest airplanes in the country when done. I think I've said it before, but I'm going to be embarrassed to park next to you when you get that thing flying.

I did use them to hold my red cube onto the runners, (size -23!) But only because I found a bin of them surplus from when Beechcraft killed off the Hawker line and picked them up on the cheap. If I'd sourced them retail they were going to cost me close to $50 a pop for that size.
 
I have Adel clamps on fuel and oil lines and on electrical wiring where possible. This is particularly better around vibration. Tyraps have their place but as someone said don’t use the cheap ones. My rule of thumb that follows AC43.13-1B for clamping is to use clamps anywhere a broken tywrap would result in the loose item contacting controls or anything with relative motion. . I am an old helicopter guy, and we clamped everything in the shake machines. Surprisingly, the big box stores will carry mil spec ones Tyraps from commercial electric. They are marked on the package.

The Adel clamps MS21919DG- xx. The dash number is the inside diameter in 1/16ths of an inch, i.e. a -6 is 3/8”. For wires the DG is changed to WDG. That adds a wedge to the cushion to help prevent wire pinching. You can use the WDG on tubing also. The neoprene clamp cushions don’t hold up as well to oil. The HT (HT replaces the DG) clamps are specifically for high temps, like near an exhaust pipe. Colors of the rubber can be meaningless so don’t depend on that.
 
Powder coat under the zip ties still look new. Assuming they're the cheap ones too. I could swap to the grip locks
 
Geez Larry- those things are anywhere between 2 and 15 bucks a pop for the common sizes. I stand by my opinion that they're overkill for most of what we're doing, but you're going to have one of the nicest airplanes in the country when done. I think I've said it before, but I'm going to be embarrassed to park next to you when you get that thing flying.

I did use them to hold my red cube onto the runners, (size -23!) But only because I found a bin of them surplus from when Beechcraft killed off the Hawker line and picked them up on the cheap. If I'd sourced them retail they were going to cost me close to $50 a pop for that size.
I got them at an Airventure long ago. Can't afford them now!
And as much as I would like to think she's an award winner, she's just my Lucy. Anyone can park next door and be welcome to share space, beer, whatever.
 
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