12 volt and cordless impact wrenches are also available. Motors need
inverters with more guts than the rating due to the inhertant in-rush
current. You would need an 1800 watt inverter or one rated to that for a
surge. To deliver 900 watts at 12 volt you need (900/12=75) 75 amps of
current. Add another 15% for inefficiencies and you can see that a cheap
inverter plugged into the cigarette lighter socket will not do the trick.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Courtney Hook
Sent: Sunday, November 02, 2008 4:43 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Lug nut stripped

Ok, my 120volt impact driver, is rated for 240 ft/lbs of power, which I
believe, it whipped off nuts on my type 2 like nothing. It is a double
insulated 7.5 amp 900 watt motor. That means if you can invert 900 watts
of
power you should be good to go. This thing is NOT small however, it's
actually bigger than my air impact gun. I bought it at Canadian Tire, but
it's just the same gun as marketed by numerous companies.

http://www.canadiantire.ca/browse/product_detail.jsp?FOLDER%3C%3Efolder_id
=1408474396673423&bmUID=1225662116276&PRODUCT%3C%3Eprd_id=845524443308583&
assortment=primary&fromSearch=true

Courtney