Scott and others:

Thanks for all of the information.  I need to refinish my deck this summer.  It's cedar and I'm not sure what was last applied.  Before using Penofin Marine Grade, I plan on sanding with Granat 80 grit.  I also plan on doing just a few boards at a time or I won't be able to reach them to rub out the excess.

Do you also recommend using any stripper/prep products or should the sanding (RS2 E hooked to CT22) be sufficient on its own?

Thanks in advance,
Phred

Whatever you do dont pressure wash it. You will leave marks everywhere. If you want to do it right and you want it to look like Warners posts you will have to sand it fully. Do you have a RO 150? It would pay for itself if not. Get 50,80,120 grit. Ive used Rubin in the past but others will also work. Do one pass in the lower grit 50 or 80 depending in the grinding setting and one pass with 120 in the fine finish setting to sand out swirls from first pass. This is only what has worked for me on certain decks, you may need more or less sanding. blow it off really good before finishing. Yours looks easy from the pics. Sink all nails and screws before sanding, Eric

Hey Lloyd

Sorry I missed this.

For best results on new or sanded wood, do two coats of this:https://epifanes.com/na/store/varnishes-and-clear-finishes/woodfinish-gloss/

Followed by 1-2 coats of this:https://epifanes.com/na/store/varnishes-and-clear-finishes/woodfinish-matte/

Sand between coats. 150/180/220/240 is a nice range to be in as you step up through the grits. And I absolutely recommend using the epiphanes brushing thinner. It is critical.

Also, the pricing in these links is really good, WAY better than I can get it for locally. It is remarkable stuff. Just maintain it.

I like the Granat but it might not tough enough for this kind of heavy sanding.  Id love to see Granat with a thicker more durable backing material.  You could try Cristal if you're finding the Granat to be falling apart on you.  You'd need to be careful because Cristal can leave a deep scratch pattern behind that can take a lot of work to remove. 

The Ras would work but you'd need to get through the learning curve to sanding without doing damage on the softwood.   

OK...finally got the deck done and wiped down and the deck looks great.  By mid Nov things will start getting cold and even some snow by then so is there any reason to put another coat on it in Oct?  What happens next spring..will it need to be sanded again and reinstalled? 

Here's an update on my deck:
1)  first of all thanks for all of the advice from Scott, Eric, and everyone else in this thread--it gave me the knowledge and confidence to tackle this job.
2)  a major overhaul of our irrigation system interfered with my plans for the deck, but I finally got the major portion finished with a first coat of Marine Oil.  I plan to do a second coat in 2-4 weeks, before the weather turns.
3)  I ended up sanding with my RS2E.  Pluses = this sander did a good job of leveling across boards and overall worked well for hours on end with minimum vibration.  Minuses = much slower than a RO-150 would have been, but budget issues dictated that I use what I had.  My boards weren't cupped too much--but the RS2E certainly let me know which ones needed flattening!  The vacuum channels in the base got clogged a few times with debris from between the boards.  It would become obvious when sawdust started being left behind on the boards and was easily remedied by removing, cleaning, and reinstalling the sander base (including vacuuming the dust ports).
4)  I really appreciated the CT22 and ClearVue Mini CV06--there ended up being a lot of dust that I was much happier to have end up in the collection bin rather than in the filter bags or everywhere else.
4)  I used Granat 80 followed by Brilliant 150.  I echo Brice's comment that Granat would benefit from stronger backing paper, but overall was very impressed as I didn't have to go through all that many sheets.

Thanks again to everyone--especially the professionals who offered advice without anything other than psychic/karmic compensation!

Fred