Replies

1. 
   chairmake1 | May 28, 2003 11:24am | #1

   Well- the only time that I use the 180 grit is when I'm sharpening

   my plain irons or bench chisels. I go from 150 grit to 220 grit, but

   most times I stop at 150 grit because I stain most of my projects.

   Robert

1. 
   forestgirl | May 28, 2003 07:55pm | #8

   Bert, sorry I missed your post the first time.  You too deserve recognition for perceiving my question accurately!  (Am I grumpy this morning?  Must be!)forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl   ;-)

1. 
   chairmake1 | May 29, 2003 01:02am | #15

   naw not the grumpy type - not that I've read - -

   Why use sandpaper all the time?

   I use a scraper after the plane - I don't have all of that fine dust floating around the shop to sweep or to inhale - it does take a little practice, but a few strokes brings little shavings and a nice sheen to the surface. There are times that sandpaper is the only way to achive the results you desire and I will start with 100 or 120 grit - then to 150 and maybe/rarely will the surface require 220 grit. I belive that anything after 220 grit will burnish the surface and cause finish/stain failure to some degree.

   Robert

2. 
   TomT226 | May 28, 2003 02:18pm | #2

   Depends on what kind of wood and finish you're using. On hard maple I go from 150-220. Oak the same. This would be for unstained and either nitro or water based lacquer finishes. Oil finishes (Watco) with open grained wood, stop at 150, get some 220 or 240 silicon carbide paper, and put your oil on, sand with it wet, and wipe the slurry into the pores cross grain. Do this twice, and wipe on one last coat. Fills the pores and makes it silky smooth.

   For painting (face frames & cabinets) I generally stop at 150 for poplar and soft maple, and all plys.

   Always use npaptha to clean sanded areas prior to finishing. Dries quick and doesn't raise the grain. Stay away from tack cloths. They can leave a residue that may interfere with some finishes.

3. 
   notDusty | May 28, 2003 05:16pm | #3

              Different brands of sand paper are very different as I think you know. In general 180 is not doing that much between 150 and 220 . And as far as 320 , at that point you are basically polishing the wood , this can cause problems when staining . The pores seem to close and it can be like trying to paint on glass, sort of.The newer R.O. sanders do such a great job that if anything you may not need to use as fine a grit to accomplish the same results.I personally belt sand with 100 then finish sand with 100 to remove the inline sander marks then generally go to 220 and have been doing so for 25 years. The key to any sanding IMO is keep the sandpaper fresh and don't let it get loaded up. Saving money by trying to extend the life of the abrasive can cost you more in the end.             good luck

         

4. 
   MichaelLomax | May 28, 2003 06:00pm | #4

   Hello Jamie,

   Regarding skipping 180, you will get more opinions here than maybe you want.  Here is a link to Western Tool Supply.  If you can get to one of their stores, they carry Mirka sandpaper, another high quality brand.

   http://www.westerntool.com/loc_main.asp

   Lomax

1. 
   forestgirl | May 28, 2003 07:28pm | #5

   Hi Lomax, you win the prize! . . . as the one who grasped the fact that I was asking about sequence, not when to stop or which grit to use on which woods.  You didn't express and opinion though, so...what would it be?

   I'll check out the store in Woodinville, as I go up there about once a month or so.

   Work well and safe!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl   ;-)

5. 
   HowardAcheson | May 28, 2003 07:29pm | #6

   Here is some info that may be useful.

   Sanding wood--hard or soft--beyond 220 does nothing more than burnish the wood making staining difficult. This is particularly true if you are using a pigment stain which sits on the surface and relies on "nooks and crannies" to impart color.

   A number of years ago a shop I was involved with did series of adhesion tests with various finishes and sealers. As part of this test we explored adhesion based on sanding grit. We found about the same adhesion up to 180 - 220. Beyond 220 adhesion dropped off due to burnishing of the underlying wood particularly when non-linear machine sanders were used. This was tested on birch panels. We also found that the resulting smoothness of the first coat of finish was not materially affected by the smoothnes of the underlying wood for sandpaper grits between 150 - 220.. Thin finishes such as lacquer could be affected by grits less than 180. The smoothest surface substrate for final finishes was obtained by sanding lightly after the first coat of finish was applied and dry. Which makes the case for a thinned first coat of finish.

   So our conclusion was that sanding beyond 180-220 was a waste of time and could be actually detrimental. But, there was a big appearance affect if the surface was not hand sanded in the direction of the grain using the highest grit used on the sanding machine. A ROS at 180 grit required final hand sanding with the grain for optimum appearence. If not hand sanded, swirl scratches would show. Final hand sanding in the direction of the grain is a must.

   To carry it one step further, sanding at 320-400 grit after the first coat and subsequent coats was the optimum. Any finer and adhesion problems were encountered. No improved appearence was noticed by between coat sanding beyond 320 for varnish. 400 was the sweet spot for thinner finishes.

   I think you will find similar thoughts in the popular finishing books but YMMV.

1. 
   forestgirl | May 28, 2003 07:53pm | #7

   Howie, I appreciate your info and have seen in earlier in other threads.  Please note though:  I am not asking for info about what grit to stop at!  You can safely assume I'm sanding to 220 or 320 for a reason (I've done several sample boards, and the 320 is giving me the color and contrast I want).

   I  do  want to know if the 180 step between 150 and 220 is a waste of time, in the opinions of my fellow Knotheads.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl   ;-)

1. 
   erich | May 28, 2003 08:13pm | #9

   Hi Forestgirl,

        Not getting what you'd like, huh?  I probably should have an opinion here, however, I'm not experienced enough to give you one of my own that I'd rest my laurels on.  BUT, I can tell you that in learning about sanding off water-based pore filler after application I've learned from Jeff Jewitt to start off with "...150 OR 180 grit...".  That's from his recent book and it didn't seem to me like he made that much of a distinction between the two.  Maybe he'd be able to clear it up for you over at H.S., I haven't looked today to see if you put up a similar post over there.

        It's been raining here for like a month (Virginia), I feel like I should be in your neck of the woods. 

        Good luck!

                                           Erich     

       

1. 
   forestgirl | May 28, 2003 08:20pm | #10

   Ahhhh, I was wondering where our rain went!  It's been gorgeous over here, but some rain due back this afternoon.

   Dontcha love Jeff's stuff?  Starting at 180 is certainly a thought.  I usually take a sample board and test a couple different grits to see what seems logical to get the planing marks off and get started.  At least I've learned that it doesn't pay to (a) start with a too high grit or (b) skip too far for the next grit. 

   I don't usually post in more than one forum with a given question -- only when I've stumped one group do I move on to another, and that doesn't happen often here at Knots!

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl   ;-)

   Edited 5/28/2003 1:21:29 PM ET by forestgirl

1. 
   MichaelLomax | May 28, 2003 08:32pm | #11

   In my opinion, you should have no trouble skipping from 120 to 180.  I do this all the time.  I have read somewhere that it is not the best course of action but that was problably written by some weirdo that actually liked to sand.

   I am sure others will not agree with me but I really don't see the need to step through each grit for most projects. IMHO.

   Lomax

   http://www.artfulwoodworks.com

2. 
   erich | May 28, 2003 09:41pm | #12

   Hey again,

        I guess I wasn't really thinking about starting at 180, though I suppose you could, I just meant he didn't act like there was much difference between them so it seems to me that you could skip from 150 to 220 without missing anything that important.  There's always two way of skinning a cat, eh?  He was talking about starting at 150 or 180 when removing cured filler.  Maybe not for general purpose sanding, though I don't know?

        Ditto on the not being able to stump the Knotheads too often, and double ditto on the loving Jeff's site, books, and products.  The first time I called there to order some shellac and the Crystalac pore filler the woman who I was ordering form (maybe his wife?) said, "Just a second, I have to put Jeff on the line."  So here I was talking to THE Jeff Jewitt and feeling all embarrased, and he was SO nice.  Offered me all kinds of tips on using the products and what not.  I actually started off with, "This is Jeff?  Jeff JEWITT?"  Can you believe that?  I'm such an idiot sometimes :)...  Later, and hope your rain holds off...

                                                                  Erich  

3. 
   BG | May 28, 2003 10:07pm | #13

   FG,

   Sixth day in a row of rain, at least its finally warm enough to spend quality time in the basement shop.  I'm in the process of sanding a coffee table made of ash...so I'm reading your post with great interest.

   It seems to me Howie shared the most important information...hand sanding as a final step...and 220 is fine..400 between coats. 

   Relative to your question, isn't it all relative?  I usually start with 100 grit then 180 and 220.  After I make sure all the big scrathes are removed (ie the 100) the sequence of grits is really just to make smaller and smaller scratches in the surface.  Therefore, you could go 150 and 180 and spend less time with each or more time with 180..and your hand is usually the judge.  Am I missing something? 

2. 
   HowardAcheson | May 29, 2003 01:37am | #16

   You can be the best judge of whether skipping a grit is OK. The idea of sanding is to sand until you get the sanding marks out from the prior grit. In theory, you can sand a rough sawn board with 220 if you want to spend the time and you can afford the amount of sandpaper it would require.

   So, you can skip the 180 as long as you are satisfied with how it looks when you sand with the 220. Different woods will react differently. For maples, I first scrape off the planer marks then go to 120, then 150 and finish with 180. For softer woods, I skip the 150.

   It also matters if you are staining, particularly with a pigment stain. Pigment stains more readily highlight sanding marks so more dilligence is required.

2. 
   Elcoholic | May 28, 2003 10:19pm | #14

   "A ROS at 180 grit required final hand sanding with the grain for optimum appearence. If not hand sanded, swirl scratches would show."

   I was wondering if the ROS used had a pad brake?  I've noticed a big difference between my Bosch pistol grip and Makita palm sanders, the latter being less aggressive and having a better brake is much less likely to leave swirl marks.  I also suspect the eccentric orbit is tighter on the Mak.  I usually switch to the Makita at 180 and stop at 220.  Then I wet it down to raise the grain and hand sand with the used 220 disk on a 3M hand pad.

   I've also noticed that different colorants will show sanding flaws differently.  Dyes (waterbase Transtint or Solarlux NGR) are the most forgiving and gel stains are the absolute worst.

   I usually go 100-120-150-180-220 without skipping but I'm thinking of dropping the 120.  John O'Connell - JKO Handcrafted Woodworking

   Life is tough.  It's tougher if you're stupid - John Wayne

1. 
   forestgirl | May 29, 2003 02:01am | #17

   "and gel stains are the absolute worst" ---  Uhhhhh, thanks for the warning!  This current project involves my first experience with gel stain.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl   ;-)