Having probs assigning file type and creator codes

I’m a rank amateur at AS.

Here’s what I’ve got, after Googling and swiping what purports to be working AS code from hither and yon. The first section (prior to telling Finder to activate) works on its own with result “PDF”; I don’t know that the first section is necessary or useful but one site indicated that it was, which is why I’m including it.

set theNewNewFileType to ""
repeat with eachLetter in "PDF"
	set thenum to ASCII number of eachLetter
	set theNewNewFileType to theNewNewFileType & (ASCII character thenum) as string
end repeat

tell the application "Finder"
	tell folder "PDF_TIFFIT_PS Files" of folder "Latest Version" of folder "35873_10_DNJ_NJR_ANNUALREPORT" of folder "Live_Jobs" of folder "DNJ_Digital_Color_Concepts___NJ" of folder "Clients_A_Thru_E" of disk "production"
		set listFiles to files as alias list
		repeat with iFile in listFiles
			set file type of iFile to (theNewNewFileType as string)
		end repeat
	end tell
end tell

If I replace the code-string “set file type of iFile to (theNewNewFileType as string)” with “set HereYaGo to the name of iFile”, the AS runs fine and the result pane shows the last file name from the folder indicated.

I’ve tried variants: with and without parens around “(theNewNewFileType as string)”, with and without the specifier “as string”. Error remains the same:

Finder got an error: Can’t make some data into the expected type

Finder’s AS dictionary (and the Googled AS from various webpages) indicates OSX Finder does know what is a file type, that’s not the problem. Gotta be something syntactical.

NOTE: These AS commands will be assembled in FileMaker and executed so as to make all PDFs in field-specified folders be of type “PDF” and of creator “CARO”, and will be doing so in-between doing other scripted routines, all of them looping, so the AS can’t be a droplet or a folder action. Has to be code that can execute from an FmPro “Perform AppleScript” script step, which is essentially identical to saying it has to be code that can execute from the regular Script Editor window.

Thanks in advance to any who can point me in the right direction here.

Model: WallStreet PB
AppleScript: 1.9.3
Browser: Safari) Shiira/0.9.3
Operating System: Mac OS X (10.3.8)

Thanks! Never spotted that there was a space after PDF in the filetype.