HDTenEightyP/NetNews huggingface dataset:
From: rhoover@watson.ibm.com (Roger Hoover)
Subject: Re: Northstate Equipment (Leneave)
Date: Fri, 28 Aug 1992 12:50:23 GMT
Disclaimer: This posting represents the poster's views, not necessarily those of IBM
Organization: IBM T.J. Watson Research Center
Keywords: Northstate Leneave

In article <1992Aug27.195518.23775@microsoft.com>, stevenj@microsoft.com (Steven Johnson) writes:
|> I've seen ads in FWW for Northstate machines --
|> can anyone compare their tablesaw to the Delta Unisaw or Powermatic 66?
|> Are they made in North America?  What kind of a reputation does
|> Leneave (the distributor) have?
|> 
|> 

While I have no information on the Northstate tablesaw, I did get a
brochure describing their 15" planers.  They have two models, both of
which were made in Taiwan and the same or similar to models sold by
Grizzly, Jet, and other importers.  I bought a (used) Delta 13".

LeNeave Supply, on the other hand, has given me excellent service.  In
the past year or so, I've purchased three big machines from them (2 Delta,
1 Minimax) as well as some Porter Cable power tools.  In all cases, Greg
LeNeave was able to give me a lower price than I could find anywhere
else.  They are were able to get the items on the truck the very same day.
I recommend them.

roger hoover
rhoover@watson.ibm.com
Newsgroups: rec.woodworking
From: porcelli@trabs.serum.kodak.com (Rocco Porcelli (x69853))
Subject: re:Router Alternative (Was propeller)
Reply-To: porcelli@serum.kodak.com
Organization: Clinical Products Division, Eastman Kodak Company
Distribution: na
Date: Thu, 27 Aug 1992 14:07:35 GMT


Article 3953 of rec.woodworking:
Newsgroups: rec.woodworking
|> In article <KEVIN.92Aug26113658@bremerer.cs.adelaide.edu.au> kevin@cs.adelaide.edu.au (Kevin Maciunas) writes:
|> Okay, so a 3.5 inch panel raising bit is dangerous.  What are the 
|> alternatives?

>Use a shaper instead.  The Delta light duty version is $419, the better
>medium duty version is $695 and the heavy duty version is $1659.  All
>prices are from Woodworkers Supply and include shipping.  I'm thinking
>of getting the medium duty version.

>The cost of a new router is about $200 (Ryobi RE-600) and a table is
>another $170.  ($370 + shipping) vs $419 postpaid .... hmmmmmmmm.  The
>3.5 inch Freud router bit is about $50, a 4.92 inch UC-210 shaper bit
>is $110.

I'm not sure but I really don't think you can use the large panel cutters on the small shaper so you're price comparisons are really not valid.  I recently completed a kitchen full of cupboards using a 3.25 hp PC VS plunge router and a router table similar to the one in American Woodworker a few issues back.  (Cost of a bout $30 to build).  I used the saftey raiser 3 wing bit sold by American Eagle.  I would have liked to have bought a shaper but this was a very good alternative that worked quite well.

Rocco Porcellio
Eastman Kodak Co., Rocester, NY

Comments: Gated by NETNEWS@AUVM.AMERICAN.EDU
Newsgroups: rec.woodworking
Date:         Tue, 1 Sep 1992 08:31:28 CDT
From:         Jeff Roberts <JROBERTS@UTDALLAS.BITNET>
Subject:      Re: need belt sander recomendation
              31 Aug 1992 22:25:25 GMT from <powell@WRAITH.NETOPS.CONTEL.COM>

On Mon, 31 Aug 1992 22:25:25 GMT Mike Powell 'GTE FSD Net Mgr' said:
>I am faced with having to sand several boards, that are bonded together,
>flat on one side.
>Not wanting to enjoy this task too much by hand sanding, it looks like
>a belt sander is my best option. Only one problem, I don't have one.
>
>Next issue, intended duty: medium to heavy. say a belt 3 or 4 inches
>wide.
>What to buy? at last check Makita and Porter Cable were playing leap
>frog with thier respective products.
>I am not to keen on buying Sears Power tools anymore, sooooo, the answer
>is ??????
>Suggestions are welcome.
>Mike
>--
>Mike Powell PPASEL
>"It's hard to find router bits for your cisco"
>Disclaimer: I speak for myself. No direct relation to the DUAT folks.
>internet: powell@wraith.netops.contel.com  Usenet: uunet!contel-fss!powell

Mike, I have not personally used either of these sanders but have this advice:
Buy the best sander you can afford.  Sanding is usually not the most pleasant
of various wood tasks so it stands to reason that getting good equipment would
make the job more enjoyable.
From: wack@ariel.ncsl.nist.gov (John Wack)
Newsgroups: rec.woodworking
Subject: Re: Polyurethane advice for hot dry climate?
Date: 4 Sep 92 18:46:07 GMT
Organization: National Institute of Standards & Technology

In article <1992Sep4.171935.10755@organpipe.uug.arizona.edu> apoyner@as.arizona.edu writes:
>Yes, I believe that applying water-based poly in a hot, dry climate is a
>problem.  Anyway, I had EXACTLY the same experiences as you, down here in
>Tucson.  I threw away the rest of the can...
>
>I now use General Finishes wipe-on, which is a mixture of oil and poly.  It 
>is a 2-part process - Sealacell as a first coat and Arm-a-seal or Royal
>Finish as a second, third, etc., coat (depending if you want gloss or satin).
>I like the satin (Royal Finish).  It is very easy to apply, and gives a thin
>coat which to me is less plastic looking than straight poly.
>
>Woodworker's Store stocks it, but I bought direct from General Finishes 
>when they had a special offer going.
>

I would like to second Tony's opinion on General Finishes wipe-on.  I've 
used it a bit differently, with the first coats being Watco Danish Oil,
but I've found their mixture of tung oil/poly to be very easy to apply 
and which results in a very nice, natural looking finish that still has
the hardness of poly.  I prefer to use cheesecloth for applying their
finish.  I'd check it out - it dries quickly, you can put on several 
coats in a day, and it looks great.

-John Wack
From: tbasche@itlwrk.Eng.Sun.COM (Todd Basche)
Newsgroups: rec.woodworking
Subject: cabinet maker wanted
Keywords: cabinet maker built ins
Date: 3 Sep 92 19:34:04 GMT
Organization: Sun Microsystems Inc., Mountain View, CA, USA
NNTP-Posting-Host: itlwrk

Hi,
I am looking to find a cabinet maker/ etc. to make some builtins
for my home. I am looking for this unit to hold my Tv and stereo
and books etc. ALso lots of room for knicnacks and doors to hide some of the stuff.
Nothing very high tech , but I want it to look nice.
Can anyone reccomend someone in the local area for me to talk to about this.
Thanks,
Todd Basche
todd.basche@sun.com

please email directly back to me on this as I dont read this
newsgroup.
From: apoyner@as.arizona.edu (Tony Poyner)
Newsgroups: rec.woodworking
Subject: Re: Frequently Asked Questions about Electric
Date: 1 Sep 92 17:01:52 GMT
Reply-To: apoyner@as.arizona.edu
Organization: MMT Observatory, Univ.of Arizona


Could you explain what _Service Factor_ for an electric motor is?

I have just paid an arm and a leg for a new furnace blower motor because
it required SF of 1.25 instead of 1.0.

---
Tony Poyner                               apoyner@as.arizona.edu
Multiple Mirror Telescope Observatory     Tel   (602) 621-5185
Univ. of Arizona, Tucson, AZ 85721        Fax   (602) 670-5740
Newsgroups: rec.woodworking
From: wedge@bnr.ca (Rick Wedge)
Subject: Re: Patience
Reply-To: wedge@bnr.ca (Rick Wedge)
Organization: Bell-Northern Research Ltd.
Date: Wed, 26 Aug 92 17:00:09 GMT

In article <1992Aug25.164440.21362@news.arc.nasa.gov>, doshay@ursa.arc.nasa.gov (David Doshay) writes:
|> In article <daniel.27@osefs1.ssd.lmsc.lockheed.com>, daniel@osefs1.ssd.lmsc.lockheed.com (DANIEL Sedergren) writes:
|> |> ... much deleted on having a good attitude ...
|> |> So, the next time you get tempted to hurry the project along, stop and ask 
|> |> yourself "where do I get my satisfaction?"  Rather than "satisfaction from a 
|> |> job well done," maybe it should be, "satisfaction from a step well done."
|>                                                                  ^^^^^^^^^^
|> 
|> or perhaps even better, a step progressing well. (present tense, neither past
|> or future)
|> 
|> David		doshay@soma.arc.nasa.gov
|> 
|> The thought police insist I tell you:
|> my thoughts, not NASA's
|>  

First of all I want to commend you, Daniel, for a wonderful story.  My 
interpretation is along the lines of David's but slightly different.  
The joy should not come from anything being "well done" or "progressing
well".  Rather, the joy should come simply from the act of 'doing'.

Rick

Newsgroups: rec.woodworking
From: kfitzsim@magnus.acs.ohio-state.edu (Kevin Fitzsimons)
Subject: Re: Inca 10.5" bandsaw
Organization: The Ohio State University
Date: Fri, 28 Aug 1992 13:11:01 GMT

In article <1992Aug25.124227.13110@sei.cmu.edu> nhw@sei.cmu.edu (Nelson Weiderm
an) writes:
>
>The Inca 10.5" bandsaw I purchased last week comes with an
>attachment to the fence which is about 10" long and slides
>forward and backward parallel to the fence.  It is attached
>with a through bolt so it can be removed for normal
>operations with the fence.  Are there any Inca owners that
>know what the attachment is for?  It is positioned on the
>back third of the fence so it is hard to see how it could be
>used as a stop.
>
>I'm still having some setup problems, but I think that I
>will be pleased with the saw.  My biggest complaint is with
>the instruction manual.  First, it does not match the saw
>(allen screws have been replaced with slotted screws), and
>as a previous poster pointed out, they do not provide any
>decent directions on tensioning the blades.  They say to
>tighten "according to the width of the blade," but do not
>say whether wide blades or narrow blades should receive more
>tension.  The parts breakout is horribly complex and the
>parts are given numbers, but not names.  (If the attachment
>on the fence had a name, maybe I could have figured it out.)
>The manual is in three languages, German, French, and
>English.
>
>The saw is made in France, not in Switzerland as I had
>expected.
>*--------------------------------------------------------------------*
>*  /X\ // \\ /X\ //   Nelson Weiderman    Software Engineering Inst. *
>* // \X/   \X/ \X/    nhw@sei.cmu.edu     (401) 783-6863             *
>*--------------------------------------------------------------------*
I talked with Mark Duginske who wrote the BANDSAW HANDBOOK about the Inca 
bandsaw. For one thing, Mark does demos for the Inca (Garrett Wade) at wood 
shows. He uses them in his own shop. (See the WOORKSHOP BOOK).He gave me some 
specific tensioning information for the Inca 10.5" saw. It depends on the size 
of the blade. I'll find the settings and post them.
Buy his book, THE BANDSAW HANDBOOK. It is great for setting up the saw, and he 
often uses the Inca as an example. He also uses the Delta.
Newsgroups: rec.woodworking
From: isr@rodan.acs.syr.edu (Michael S. Schechter - ISR group account)
Subject: Re: Black Lacquer finish?
Organization: Institute for Sensory Research
Date: Mon, 31 Aug 92 11:02:29 EDT

In article <16852C24F.SYSGAM@SUVM.SYR.EDU> SYSGAM@SUVM.SYR.EDU (Glenn A. Malling) writes:
>In article <1992Aug24.202514.26573@cbnewsl.cb.att.com>
>piz@cbnewsl.cb.att.com (G G ZIPFEL) writes:
>>        Is there a "Black Lacquer" product?
>If what you're looking for is the black piano finish it's just
>black nitro-cellulous lacquer.  See you local auto paint store.
>It's the same stuff they put on GM cars before the acrylics
>became common.
>Glenn A. Malling (SYSGAM@SUVM) or sysgam@suvm.acs.syr.edu

Availible in most chains under brand name "Classic Spray"
comes in black, blue, candy apple red, clear top coat and
a really bright yellow. Looks excellent after sanding/buffing.
oh yes, and in white also...  
--
Mike_Schechter@isr.syr.edu | XLII,B,+3dB,Non-Nak | Make Tapes, Not War
From: erickson@taurus.cs.nps.navy.mil (David Erickson)
Newsgroups: rec.woodworking
Subject: Re: need belt sander recomendation
Date: 3 Sep 92 01:08:01 GMT
Reply-To: erickson@cs.nps.navy.mil (David Erickson)
Distribution: usa
Organization: Naval Postgraduate School, Monterey CA

>In article <920831175524@wraith.netops.contel.com> powell@wraith.netops.contel.com (Mike Powell "GTE FSD Net Mgr") writes:

>I am faced with having to sand several boards, that are bonded together,
>flat on one side.
>Not wanting to enjoy this task too much by hand sanding, it looks like
>a belt sander is my best option. Only one problem, I don't have one. 

>What to buy? 
>Suggestions are welcome.

I've owned and worn out two beltsanders: a Sears Craftsman and
a Skil.  The one I have now will probably outlast me - and it was a
gift from a retired carpenter who used it 20 years.  It is a Porter 
Cable #504 worm drive sander.  It is heavy, powerful, has a nice comfortable 
handle, & takes lots of abuse.  And parts are still readily available.

-Dave Erickson
From: pauln@hpubvwa.nsr.hp.com (Paul Newbry)
Date: Fri, 28 Aug 1992 21:00:28 GMT
Subject: Re: Purchasing Planes in Salt Lake City Area ?
Organization: Hewlett-Packard Bellevue Sales
Newsgroups: rec.woodworking

There is nothing near Salt Lake City. :-)
I'd try either Ernst Home Center or TOOL supply.
TOOL supply is a speciality store with prices to match
but they have a good selection of quality products.
From: SDOGGETT@cmsa.gmr.com
Newsgroups: rec.woodworking
Subject: Thanks for filler info
Date: 3 Sep 92 12:38:46 GMT
Organization: GM Research Labs


   For all of you who took the time to offer help with my questions on paste wo
od filler, thank you.  I tried to respond individually, but had problems with s
ome addresses.  Thanks again.  Spencer Doggett




Newsgroups: rec.woodworking
From: korsberg@kirk (Ed Korsberg)
Subject: Re: Water and Wood: A beginner's question
Organization: Allen-Bradley Company, CIS-AA - Ann Arbor MI, USA
Date: Tue, 1 Sep 1992 12:17:42 GMT

In article <1992Sep1.013038.27132@hpcvaac.cv.hp.com> billn@hpcvaac.cv.hp.com (bill nelson) writes:
>brill@unagi.cis.upenn.edu (Eric Brill) writes:
>: 
>: I'm new to woodworking.  This weekend, I tried to make a maple cutting board.
>: I edge glued two pieces of 4/4 maple together, and then routed a cove along the
>: sides.  I finished the piece with a nut-oil finish.  Then came the problem.  I
>: figured that I had better raise the grain and sand it down again so when I gave
>: the board away it would remain smooth after washing.  So, twice I briefly
>: soaked the board in water and sanded it down.  I later noticed that this caused
>: the board to cup considerably.  Could somebody please tell me what I did wrong?
>: If the water caused the board to cup, how can I raise the grain without causing
>: this to happen, and how can I protect the board from cupping when the future
>: user decides to wash it?  Thanks,
>
>You can reduce cupping by using quarter-sawn stock.
>

I'n new to woodworking too.  Could you please explain what quarter-sawn stock is?
-- 
Ed Korsberg             E-mail: korsberg@aa.ab.com
Allen Bradley Inc.      phone:  313-998-2470
555 Briarwood Circle
Ann Arbor, Mich 48108
Newsgroups: rec.woodworking
From: games@max.u.washington.edu
Subject: Re: Air Compressor Wisdom
Organization: 
Date: Wed, 26 Aug 1992 17:26:30 GMT

In article <Aug.26.11.02.24.1992.27332@pilot.njin.net>, ron@pilot.njin.net (Ron Natalie) writes:
>> Also, has anyone used PVC (sched 40 or 80) for 125 pound air?  I notice
>> that all the air in the lab here is in 3/4 inch copper pipe.
> 
> It will burst.  There is plastic tubing availble designed for air
> distribution though.  There were some "Now I Know" type letters in
> FWW about this.
> 
> -Ron


Note that he also asks about schedule 80. This is a much thicker wall than
sch. 40.  We used a good 3000 feet of it in the shop at showlites for our
stuff.  Much easier to glue together, and cut for adding things, etc...

Or maybe it was ABS, hmmm.   But it WAS schedule 80 pipe.

Anybody have a diatribe on the differences between the different types of
plastic?

			John.
Newsgroups: rec.woodworking
Subject: Re: Patience
From: grspangler@ualr.edu
Date: 27 Aug 92 08:22:41 GMT
Organization: University of Arkansas at Little Rock

In article <daniel.27@osefs1.ssd.lmsc.lockheed.com>, daniel@osefs1.ssd.lmsc.lockheed.com (DANIEL Sedergren) writes:
> [...nice bit about patience deleted...]

i bet you tell a hell of a good story.

> So, the next time you get tempted to hurry the project along, stop and ask 
> yourself "where do I get my satisfaction?"  Rather than "satisfaction from a 
> job well done," maybe it should be, "satisfaction from a step well done."

how about satisfaction from doing a job well???

===========================================================================
USMailNet: Guy R. Spangler  2801 S University Ave  Little Rock, AR  72204
AT&TNet:   (501)569-3345
InterNet:  GRSPANGLER@UALR.EDU

Disclaimer: What?!?!?  I didn't say that!!!!!
From: hmoss@hpnmdla.sr.hp.com (Howard Moss)
Date: Thu, 3 Sep 1992 23:55:07 GMT
Subject: glue removal question
Organization: Hewlett-Packard, Santa Rosa, CA
Newsgroups: rec.woodworking

Sorry if this is a FAQ, but:

  I'm trying to repair 2 small tables for a nursery school. On one, I have 
  to remove some glue that was under a piece of wood that snapped off. 
  Scraping it doesn't seem to remove all of the glue. Any hints? (soak 
  in hot water, sand it off, rhythmic incantations...)?

  Also, any particular type of glue? Normally, I just use Elmer's
  wood glue (the yellow stuff...).

Thanks,
Howard Moss
hmoss@hpnmdla.sr.hp.com
From: jcw1@Ra.MsState.Edu (Jeff C. Wilson)
Newsgroups: rec.woodworking
Subject: IWF
Date: 27 Aug 92 17:29:33 GMT
Organization: Mississippi State University


I went to IWF this year and wow. I saw lots
of woodworking stuff. I did not see Grizzly
at the fair, bud woodworkers supply  with
woodtek were. I liked the woodtek stuff.
They had a 3 spindle shaper 3hp for $3100.
looked very nice. 

Went to Highland hardware in Atlanta, glad i
do not live any closer than i do (boy woul i be broke).
From: landers@adam.dseg.ti.com (Dave Landers)
Newsgroups: rec.woodworking
Subject: Re: BANDSAW INFO REQUIRED
Date: 27 Aug 92 14:45:52 GMT
Reply-To: landers@wilma.dseg.ti.com
Organization: Texas Instruments Inc

(Tried to mail this, but it bounced.)

I recently (about 3 months ago) got myself a Delta 14" BS.  I am VERY happy 
with it.

I thought about the Taiwan brands, but I wasn't sure about the quality, as
most of them seem (to me) to be reverse-engineering jobs of Delta and others (by
this I mean that they bought a Delta, measured it, and started building, without
any of the original design thought process or tolerancing specifications).
Now, before I get too many flames on this, I know that I'm not being entirely  
fair, but it was enough for me to spend the extra money on something I can 
keep for a while and get parts for.  It was also important to me to be able to
go to my local hardware/home-center/woodworking stores to see more than a picture
in a catalog (even if I didn't buy from them).

I wanted to bandsaw to do all the standard things, but I really hope to
do a lot of resawing, so I opted for the height extension.  The stock (with
the open stand) 1/2 HP motor didn't thrill me for resawing 10 - 12" hardwood.
I'm sure there are ways to do it (skip tooth blades and all), but I just
don't like being under-powered.

I also didn't like the idea of buying the enclosed stand just to get the 3/4 HP
motor (at least that's the way it was everywhere I shopped).  It worked out
to about $180 extra for a 3/4 HP saw.  Gack!

I ended up getting the 14" saw with the open stand and 1/2 HP motor.  I found this
for about US$500 (but they're up to $530 now).  I also got the height extension
($85).  Then, I bought a 1 HP, 1725 RPM motor for $100.

I ended up with a good, well powered saw for under $700.  Buying the motor separate
saved me about $100, PLUS I have a new 1/2 HP motor for my drum sander.


Source for motor:

Burden's Surplus, 1015 West "O" St., Lincoln, NE  68501-2209, 402-474-4055 or 
1-800-488-3407 from the States.  Note that this motor is reversable, you'll need 
to make sure any replacement motor is either reversable or spins the right way.  
Also, this is a new motor, not used.  A good bargan, since most places I see 
1 HP 1725 RPM motors want around $140.  Burden's has a large selection of 
new and used motors, pumps, blowers and the like at reasonable prices.
[Not an ad, just a plug from a satisfied customer]

	---------------------------------------------------------
	Dave Landers			landers@wilma.dseg.ti.com
	---------------------------------------------------------
	Opinions expressed here are my own.
	Words typed here are likely to be misspelled.
	Humor expressed here may not be smiley-faced.
	Facts offered here may not be factual.
	Any truth here is purely coincidental.
From: wtc@cbnewsl.cb.att.com (william.cox)
Newsgroups: rec.woodworking
Subject: Re: Air Compressor Wisdom
Keywords: air pressure pipe pvc brittle
Date: 31 Aug 92 21:23:37 GMT
Distribution: na
Organization: AT&T UNIX System Laboratories

In article <1992Aug26.135418.3255@titan.ksc.nasa.gov> myjak@titan.ksc.nasa.gov (Michael D. Myjak) writes:
>> ron@pilot.njin.net (Ron Natalie) writes:
>>> Also, has anyone used PVC (sched 40 or 80) for 125 pound air?  I notice
>>> that all the air in the lab here is in 3/4 inch copper pipe.
>> 
>> It will burst.  There is plastic tubing availble designed for air
>> distribution though.  There were some "Now I Know" type letters in
>> FWW about this.
>> 
>> -Ron
>-- 
>
>It will not. I've seen several shops using PVC plumbing for compressed
>air. The cheap stuff will burst, as will sch-40 and sch80 if their
>impacted, or over stressed. I have schedule-40 3/4" PVC lines running
>throughout my shop and garage and (illegal) paint bay. Sch-40 3/4" PVC
>is rated at 440psi (!) and can actually sustain much more than before
>it fails catastrophically. 
>
> However, as I had responded to the original poster, PVC is brittle,
>and as such, is suspectable to stress facturing if to much force is
>used while connecting and disconnecting the commonly used
>"quick-disconnects". The way to prevent this from happening is to
>fix-mount the PVC and attach the quick disconnects using a short piece
>of flexible 3/8" or 1/4" rubber hose.

Again, the voice from the old car dealership/body shop...

We used standard 3/4" iron pipe, with standard iron fittings, for air
conduction around a large (33,000 sq foot) building.  Never had any
problems, and iron pipe isn't exactly "brittle."

For home, I've been planning on leaving the compressor in the garage,
running a trunk line of iron pipe with quick disconnect fittings at intervals,
and a fitting to connect a standard air hose from the compressor
to the trunk.  

I don't care for the potential results from not being careful enough
with brittle PVC.  It's just not worth the risk to me.

	bill

	William Cox
	bill@usl.com
	UNIX System Laboratories, Inc
	Summit NJ 07901
From: mmf@evolving.com (Mark Frazier)
Subject: Re: Incra or Leigh?
Date: Wed, 02 Sep 1992 13:56:59 GMT
Organization: Evolving Systems, Inc.
X-Newsreader: Tin 1.1 PL4

wedge@bnr.ca (Rick Wedge) writes:
: With all the posts about the Incra jig, I'm wondering if that is the most 
: popular jig out there.  Is anybody using the Leigh dovetail jig?  How does
: it compare to the Incra?  I think it's a bit more expensive, is it worth it? 
: 

For THROUGH dovetails, the Leigh is the one which will do them completely.
For the Incra, you have to clean up the pins with a chisel. Not that hard,
but still more work by hand.

The Leigh is easier for large pieces (like big drawers) and large numbers
of copies.

The Leigh can do more than dovetails. You can get a Multiple Mortise & Tennon
attatchment (MMT) to cut MMT's on boards. Either through or blind, square or
round. The square ones require chisel cleanup. Of course, the MMT costs extra
(SURPRISE!), I think about $150.

The Leigh will also let you do exotic dovetail stuff, like joining at
odd angles (in both the X and Y axis). I'm not sure how hard this would
be to do on the Incra.

MMF