Impact drivers (dewalt and the likes)

[Strega]

Anyone ever use them?

Gonna try to get an old piper resurrected this week, and Im sure there will be a ton of screws that will probably strip and need to be drilled out.. Might bring my cordless impact and see how it works.

[DonutHole]

Valve grinding compound on the tip of the screwdriver and good old fashioned elbow grease works most of the time.

[CamAero]

I run #2 "Grabits" in my Makita impact and/or cordless. Works excellent.

http://tinyurl.com/p3hfrwn

Also, make sure of course, you're using only the Snap-On serrated screwdriver tips to begin with.


CA

[Strega]

I never thought much of the snap on bits.. Vermont American used to make nice ones with the "teeth" .. but since I can no longer seem to find them, it is dewalt bits that I have found seem to work well.

[PilotDAR]

I suggest away from "impact" devices on phillips screws, it can end in frustration. I agree with the valve grinding compound on the driver tip, it works. The best phillips tips I have found are at Lee Valley tools, and are diamond dust coated, they grab excellently. They eventually wear, so buy extras, and throw away as if it's cheaper to replace the tip, than fight the screw for half an hour. I have also had success with really stuck screws by tightening them a fraction of a turn first, to "break" the seizure, then loosening. If you have access to the back side of the screws, where they protrude through anchor nuts, liberally spray them with the lubricant of your choice - I like LPS1.

[iflyforpie]

+1 for avoiding impact drivers on Phillips. The impact invariably pushes the bit out and strips the head rather than motivating it to move.

I like APEX bits. I've found Snap Ons always tend to snap off under high stress and the serrations are eroded away with heavy valve grind compound useage anyways. Connected to a Blue Point 1/4" speed handle with the big knob at the end so you can apply lots of pressure.... there are very few screws I need to drill out.

The only impact device I like to use with #2 Phillips structural machine screws is a 3x gun and a rattler... since you are in 100% control of how fast it turns.

[GyvAir]

I've tried the Dewalt style impact drivers with only moderate success. On aircraft, they seem mostly to just make the job noisier. (driving large wood screws though.. they are clearly the cat's butt) They're ok on easy to medium tight screws, but when the screws are really tight, the impact driver seems to cam out or shear the lugs out of the head of the screw more than just a plain speeder handle will.
Even a regular cordless drill with the clutch set high, just short of the "drill" setting so that it slips on the hard screws seems to rattle them out better than an impact driver.

On the hard ones, the aforementioned Old Man Knocker in the 3x gun, with the proper APEX bit and some valve grinding compound is the recipe.

Other things not to overlook:

Make sure the screw head is clean. If the bit can't bottom out due to paint and dirt, it's just going to knock the corners off the screw socket.

Make sure the bit profile matches the profile of the screw socket. If the ying doesn't match the yang, you're half beat before you start. There seem to be dozens of variations out there. I've seen people trying to use drywall bits on AN hardware, with the wings on the bit fatter than the slots in the screw. You can imagine how well that works.

Use a screw head paint cutter on panels that haven't been off since the aircraft was painted. They will turn easier and not take a dime size chip off with each screw.

[AirFrame]

Even a regular cordless drill with the clutch set high, just short of the "drill" setting so that it slips on the hard screws seems to rattle them out better than an impact driver.

This.

I've got a Black & Decker cordless screwdriver, nice and compact, not blazing fast but saves a lot of wrist effort at annual time removing all those screws. For removal, I set it on "drill" mode (silly because the only bit they include with it is a 1/16" bit that wouldn't cut through tinfoil) which locks out the clutch. For putting them back, I set the clutch about half-way, and then go around afterwards with my Snap-On and give them the final set. I don't trust the clutch on any uncalibrated powered driver for installing fasteners... Too much risk of over-torquing and stripping threads.

[GyvAir]

I don't trust the clutch on any uncalibrated powered driver for installing fasteners...

Agreed.

Even having a calibrated tool doesn't mean much, as every screw ends up having a different running torque, even on a brand new aircraft. Set the clutch for the average of 100 screws, and some will be right, but a bunch will be way over-torqued - next inspection's problem - and a bunch not even making contact with the panel.
Final torque with a speeder handle, screwdriver or similar.

[KISS_MY_TCAS]

Why, oh why does anyone help Strega when it's painfully obvious his AME hating, holier than thou self is trolling a forum? Strega, head to Canadian Tire, buy your jobber impact, destroy your airplane so you can come back and complain about people wanting you to spend money for their knowledge and experience. Please buy the cordless impact with the highest voltage available, they work better. You and photofly can hug when you trash the airplane because you sought internet help instead of actually having any real friends.

[Pat Richard]

/l\ +1

[Strega]

Why, oh why does anyone help Strega when it's painfully obvious his AME hating, holier than thou self is trolling a forum? Strega, head to Canadian Tire, buy your jobber impact, destroy your airplane so you can come back and complain about people wanting you to spend money for their knowledge and experience. Please buy the cordless impact with the highest voltage available, they work better. You and photofly can hug when you trash the airplane because you sought internet help instead of actually having any real friends.

Interesting...

Dunno what a jobber impact is.. is that something you "engineers" use?

Fyi on a plane that has not been apart for almost 20 years, (mainly #8 machine screws) my dewalt impact driver actually worked fairly well, I wasnt able to get ever screw out, but nearly.. Perhaps if I was trained and experienced in removing screws like mr tcas, I would have got them all out...

[Pop n Fresh]

Here is an impact driver.


I don't know if it should be used on an airplane.

[7ECA]

I can't believe people still want to use Phillips and Slotted screws these days, when we have an alternative...

[DonutHole]

They're not as good in some ways. The angular corners create stress risers at the torque points.

[PilotDAR]

we have an alternative...

We have the alternative, but the Americans much less so. Mr. Robertson was Canadian, a friend of mine knew him.

They're not as good in some ways. The angular corners create stress risers at the torque points.

On deHavilland Comet cabin windows yes. However, I have never seen a cracked corner in a Robertson head screw!

[DonutHole]

I saw that in some training material in ame school.

Another downside is the depth of the square. Because of the shallower head angle of aviation style fasteners there's less meat in the extremities.

I have seen aircraft come in with Robertson screws. .. they just don't 'look' right.

[photofly]

You and photofly can hug when you trash the airplane because you sought internet help instead of actually having any real friends.

Er ... how did I get dragged into this one? :scratch:

[Troubleshot]

Read up on what Strega thinks of our job title....I'm sure he can write a mathematic equation on how to remove seized screws.


http://www.avcanada.ca/forums2/viewtopi ... 27&t=45345


http://www.avcanada.ca/forums2/viewtopi ... 27&t=47157

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[iflyforpie]

#6 AN bolt? That's new...