Replies

1. 
   frenchy | Oct 09, 2007 05:04am | #1

   Phoebe,

    Sandblasting is a skill learned thru practice..

    Here's a couple of hints.. if you are plugging up chances are it's because instead of graded abrasion material you may have used something like sand to do it..

    Sand is made up of too many different sized pieces to use.. it plugs and causes dust etc..  use a graded blast media!

    You can use just about any sized compressor but the bigger the compressor the longer you can blast before  stopping while waiting for the compressor to catch up..  Well the bigger the compressor and the bigger the tank (air tank)  I've used small 1/2 hp compressors and a big 85 gallon air tank and been able to blast for several minutes before air pressure dropped too low.. , However it took that little air compressor over an hour to fill the tank back up..  blast for two minutes, wait for an hour..  yuk!  (big compressor was broken, job had to be done) 

     The sandblast cabinet can be either purchased or made.. simple plywood will work for a while if you are doing to do it cheap, just wear a great dust mask because dust will get out..

    There are cheaply made blast cabinets available thru Northern Hydraulics and Harbor freight. They work fine for light use. Really decent sized good ones are expensive..

    If you want to blast uninterrupted for a half hour or longer a minimum of a 7 hp compressor is required.  Best would be a 10 hp 3 phase compressor with a 110 gallon air tank..  You can extend your blasting time by going to smaller nozzles but that will result in smaller areas being covered..

     Gasoline and diesel powered air compressors are out there.. do not attempt to buy them in the fall.. that's when anything running commands a real premium because they are used to clean out irrigation systems so they don't freeze during the winter.

    Do not buy them in the spring or summer either.    that's when they are needed for construction and demolition work.. Mid winter is best.

     125 CFM is about the size you'd want.  most of the diesel compressors are around 185 CFM  which is really bigger than you need.

    If you'd like to know which brands to buy and what to look out for on those let me know and I'll go over them..

       

    

1. 
   Phoebe in Asheville | Oct 09, 2007 01:37pm | #2

   Thanks Frenchy, that was helpful. I would like to start with 110 volt (don't have 3 phase) and I would like the compressor to be useful for spraying and sanding - basic pneumatic tool use. I think that a big enough tank to blast for a while would be the best.I last used a $100 -plastic barrel type blaster with "blasting sand" - outside, with a respirator etc. Definitely hard labor with all the unclogging and slow going with the removal of grain in ash! I had a good size compressor (school) and did not loose air though.

2. 
   RickL | Oct 09, 2007 02:34pm | #3

   5 hp and 60 gallon tank would be minimum. You should try a google search on the subject. Try phrasing it differently for other sources.  Sandblasting isn't a new subject but it's not something typically found on furniture forum such this. Protect your lungs. Sandblasting is very dangerous to your health if not careful. Sandblasting is done with sign making, paint removal, headstones, and many other applictions if you search properly.

   http://www.tptools.com

   
   

   ---

   Edited 10/9/2007 10:31 am ET by RickL

1. 
   Phoebe in Asheville | Oct 10, 2007 03:58am | #4

   Yes, as I said I did use a respirator. And as I said the sign people (the only ones I found that do sandblasting on wood) use easily eroding wood - redwood and cedar - not Ash.I have seen wood sculptors use blasting - and some furniture makers.

1. 
   peter28 | Oct 10, 2007 04:32am | #5

   A couple of things to consider;

   There are many abrasives used in sand blasting including walnut shells which are sold in three different grits. At 100 to 125 psi it will raise the grain on any wood extremely quickly. They are sold in 50 and 100 lb. bags as I recall.

   When you reload the hopper with your abrasive, running it through a screen will help keep large particles or foreign matter out.

   The size of the tip you use in blasting will make a difference also. If you check out some monument and or headstone suppliers in your area you may be able to buy some used tips from them. As the hole in the tip gets bigger through blasting, it is no longer efficient for cutting letters in granite. You should be able to pick some up at a reasonable cost. The smaller the hole the sharper your cut will be.

   Good luck

1. 
   Phoebe in Asheville | Oct 10, 2007 05:24am | #6

   Thanks Peter,I guess 100 to 125 psi would dictate the compressor - just find one that can handle that? -with enough capacity to keep it up for a while?And do you have insight as to the actual unit (blaster?) as well? (I mean size, brand, specs that I should look for?)I wonder if I would have to mail order walnut shell abrasive...I could only find on size of blasting sand where I live and only small bags of beads (glass at Northern).Thanks all

1. 
   RickL | Oct 10, 2007 03:38pm | #7

   http://www.tptools.com has a good selection of sandblasting equipment and will give a good over view on options. You should also look in your local yellow pages and visit some place that do sandblasting. I'm sure some would give you some tips and ideas of what would be good and where to get it.

   Walnut abrasives are typically used to remove paint and minimize daamge to the wood underneath. Various abrasive grits such as black beauty. glass bead, and various sands should be available locally. Sand is usually a few bucks for a bag. They even carry it at my local farm supply. I realize some areas have less suppliers but with some local searching I think you will find what you need. Check out the local monument, gravestone companies.

   http://www.scmsysteminc.com/sandblast_process.php

    

3. 
   RAC21 | Oct 10, 2007 08:36pm | #8

   I don't have a ton of experience with sandblasting, but it's interesting, and I hope to do more, so I hope you will let us know what you learn!

   One thing that I have found is that humidity can really cause clogging and flow problems of the type you cite. You might try baking your sand in the oven for a while on low. Make sure your tank is bone dry. And install a water trap on the compressor.

   Good luck!

4. 
   Norse | Oct 11, 2007 02:43am | #9

   I sand blasted a walnut sign for my shop a few years ago. I have an 80 gal 2 stage compressor and it was taking forever. I ended up renting a construction size compressor and pot and was done with the gross removal in a few minutes. I used different grits to "sand" the sign. I do like the effect but its a messy, dangerous task. I've seen electric motors ruined by the super fine grit not to mention your lungs. For the past 15 years or so, OSHA requires outdoor blasting on construction sites to be done with water - wet blasting.
   Work safe!
   Norse

1. 
   Phoebe in Asheville | Oct 11, 2007 03:49pm | #10

   Thanks, interesting..walnut huh?hmmm... I do wear a full respirator and I think that should do it although if I get a powerful blaster I will need full coverage. What can I say I feel "bitten" by what I get from it - it is rich and textured like an animal pelt - craggy in the grooves and smooth and waxed on the surface - a textural/ visual/ sensual feast.