Changing permissions

I am writing a simple script which creates a folder tree. So far so good. However, I need the permissions to enable both the group and others to read & write. As it stands, my folder tree creates perfectly, but when I try to change permissions, my script runs into terrible problems. I run aground right at the first line (set new_folder to POSIX path of (item i of jobFolder)) and advice would be much appreciated. The only way I can think of to do this is through the shell, is there a property for permissions that I could simply apply to the folders as I create them?

Thanks,
Don

display dialog "Enter the job number:" default answer "U07MM0"
set jobNumber to text returned of result
tell application "Finder"
	activate --bring finder to the front
	set chosenFolder to (choose folder with prompt "Please select the destination folder.") --asks user where to put it
	
	make folder at chosenFolder with properties {name:jobNumber}
	set jobFolder to result
	--creates top folder
	make folder at jobFolder with properties {name:jobNumber & "_XML"}
	make folder at jobFolder with properties {name:jobNumber & "_ISSUE"} -- creates issue folder
	set issue to result -- gives a name to the "issue" folder just created
	tell application "Finder"
		make folder at issue with properties {name:jobNumber & "_MANUSCRIPTS"}
		make folder at issue with properties {name:jobNumber & "_PDF-PS"}
		set pdfps1 to result
		make folder at pdfps1 with properties {name:"f2"}
		
		make folder at issue with properties {name:jobNumber & "_SOURCE"}
	end tell
	make folder at jobFolder with properties {name:jobNumber & "_REPRINTS"} --creates reprints folder
	set reprints to result
	make folder at reprints with properties {name:jobNumber & "_PDF-PS"}
	set pdfps to result
	make folder at pdfps with properties {name:"f2"}
	make folder at pdfps with properties {name:"p2"}
	make folder at pdfps with properties {name:"s2"}
	make folder at reprints with properties {name:jobNumber & "_SOURCE"}
	--here is where we try to change permissions
	repeat with i from 1 to (count of jobFolder)
		-- Format path for use in shell script
		set new_folder to POSIX path of (item i of jobFolder)
		set shell_script_chown to "sudo chown -R root:admin "
		-- Change mode of folder to rwxrwxr-x
		set shell_script_chmod to "sudo chmod -R 775 "
		
		-- Perform both shell scripts
		repeat with this_shell_script in {shell_script_chown, shell_script_chmod}
			try
				do shell script this_shell_script & new_folder as string
				display dialog ("item " & i & " of " & (count of jobFolder) & return & this_shell_script & new_folder as string) giving up after 1
			on error error_message number error_number
				-- If error occurs beep user and bring up why there was an error
				beep
				display dialog ("Error number: " & error_number & return & error_message as string) giving up after 5
			end try
		end repeat
	end repeat
	
end tell

AppleScript: 1.10.7
Browser: Safari 419.3
Operating System: Mac OS X (10.4)

Check out jj’s article

http://www.applescriptsourcebook.com/viewtopic.php?id=14411

Sigh. So simple…

Thanks James. The functional script (in case anyone is interested):

display dialog "Enter the job number:" default answer "U07MM0"
set jobNumber to text returned of result
tell application "Finder"
	activate --bring finder to the front
	set chosenFolder to (choose folder with prompt "Please select the destination folder.") --asks user where to put it
	
	make folder at chosenFolder with properties {name:jobNumber}
	set jobFolder to result
	--creates top folder
	make folder at jobFolder with properties {name:jobNumber & "_XML"}
	make folder at jobFolder with properties {name:jobNumber & "_ISSUE"} -- creates issue folder
	set issue to result -- gives a name to the "issue" folder just created
	tell application "Finder"
		make folder at issue with properties {name:jobNumber & "_MANUSCRIPTS"}
		make folder at issue with properties {name:jobNumber & "_PDF-PS"}
		set pdfps1 to result
		make folder at pdfps1 with properties {name:"f2"}
		
		make folder at issue with properties {name:jobNumber & "_SOURCE"}
	end tell
	make folder at jobFolder with properties {name:jobNumber & "_REPRINTS"} --creates reprints folder
	set reprints to result
	make folder at reprints with properties {name:jobNumber & "_PDF-PS"}
	set pdfps to result
	make folder at pdfps with properties {name:"f2"}
	make folder at pdfps with properties {name:"p2"}
	make folder at pdfps with properties {name:"s2"}
	make folder at reprints with properties {name:jobNumber & "_SOURCE"}
	
	set everyones privileges of every folder of jobFolder to read write
	set group privileges of every folder of jobFolder to read write
	set everyones privileges of every folder of issue to read write
	set group privileges of every folder of issue to read write
	set everyones privileges of every folder of pdfps1 to read write
	set group privileges of every folder of pdfps1 to read write
	set everyones privileges of every folder of pdfps to read write
	set group privileges of every folder of pdfps to read write
	
end tell