Professional Finishing

You are not logged in. [ Login ] Why log in
(NOTE: Login is not required to post)

Sand Paper

9/8/18       
Edi Silva  Member

Website: silvawoodworking.com

Hello

What Sand paper or Sponge you guys are using after primer? I see that my guys are sanding too much and removing the primer on some spots, maybe sanding too much or not using the right product. We use 220 sand Paper, thanks for the help.

9/8/18       #2: Sand Paper ...
Robert Member

I liked 280 for primers/sealers.

9/8/18       #3: Sand Paper ...
Bob Niemeyer  Member

Website: niemeyerrestoration.com

We also will use 280 or 320, depends on how much you need to cut to get it smooth.
We dont use sponges as they are not quality controlled for grit as sheet goods are.
People think anybody can sand, doesnt take to many smarts right? Well, sanding is when most of the damage is done.

9/8/18       #4: Sand Paper ...
CraigM

I usually spray two coats of primer, first coat I sand heavy with 220 sheet and don't worry about burning through or showing substrate, I just try to get it flat. Second coat I sand with 400 sheet lightly to get grit out then spray my topcoats.

9/8/18       #5: Sand Paper ...
Adam

Good 240 like Klingspor, Mirka, 3m

If you are burning thru the primer enough that you are concerned, then you aren't putting on enough primer.

Depending on your product its common to do a tack coat when spraying primer. Hit it with a light coat wait a few minutes for it to flash off then hit it again with a heavy coat. The tack coats keeps the heavy coat from sagging or running.

9/9/18       #6: Sand Paper ...
rich c.

320 sandpaper or 320 SIASoft foam backed for contours.

9/9/18       #7: Sand Paper ...
Craig Caughlan Member

Website: wetimber.mx

320. For flat surfaces, the 1/6 sheet is wrapped around a hardwood block that has one face covered in 3/16" felt. It cuts faster and more evenly. These blocks are also used before finishing; depending on variables, the hard face of the block is used, as the felt face will follow any irregularities in the surface of the wood.

9/9/18       #8: Sand Paper ...
Robert Member

Ive retired now but back in the day, I had / still have 2 Porter Cable 505's and 2 Porter Cable 380 sanders.One set for colored primers and opaque coatings and another set for clear sealers and clear coatings.

I cut a piece of 1/8" Plexiglass the same size as the felt pads are. I removed the felt pads on both sets of sanders and replaced them with the Plexiglass.

Using 280 I'm able to shear off any proud surface areas to achieve a pretty darn near dead flat surface for successive coats.

The Porter Cable 505's are workhorses and a great time saver. Keep it " Operating Room Clean " and it will last a loooooong time .

9/10/18       #9: Sand Paper ...
Shane

We do a bit of wizardry with our opaques. We use SW Kemvar primer that they reduce specifically for us for our viscosity. our process differs depending if they are flat parts or built up glued up parts.
1st coat is a light coat/tack coat to catch any defects and scuff and fix blemishes as necessary after tack coat flashes off..
2nd-4th coats.... We wet coat the parts sometimes up to four wet passes. Waay beyond specifications here... but the key is our total mills of the system.
We generally force cure in a large batch oven.. Flat goods get sent through a heesemen wide belt sander... nice beautifully flat panels... edges are hand prepped in sanding booths after this. all other odd/ glued up parts... trims.... large assembled items go through the sanding booth to get final prep for paint. I'm a firm believer of fill it up with primer and sand it back... you will fill defects and have plenty of material left on edges if you operate this way.. key is sand very well so you don't have to much film thickness at the end.... It's very rare we go through the spray booths for a second round of primer before topcoating with C.V.
Widebelt sanding is generally done with 320 grit cross belts and 400 grit widebelts. R.O sanding and air powered jitterbug sanding with 320 grit and 400 grit depending on the preppers preference. Hand sanding is done with klingspor ultraflex 220 grit sponges.. they leave a 320-400 grit scratch. I could see where your prep work is not turning out well with 220 grit sanding..and seeing burnt edges and burn throughs. that's a bit harsh for a final sand for a good paint job... 320-400 grit is plenty of a good mechanical bond for a 40 sheen paint job.... you will still see scratches anything past 50 sheen if you don't move up the grits...

9/10/18       #10: Sand Paper ...
Adam West  Member

Website: http://www.surfprepsanding.com

I work for SurfPrep sanding. We use a specially designed sponge on a 3x4" sander on flat surfaces to cut primer all the time. If the primer is harder we use film or paper sheets to cut it flat.

9/13/18       #11: Sand Paper ...
mauricio poli Member

We use 280 after first coat. And 320 and 360 in the second coat.
SIA paper.

  • Post a Response to this thread
  • notify me of responses to this topic
  • To receive email notification of additions to this forum thread,
    enter your name and email address, and then click the
    "Keep Me Posted" button below.

    Please Note: If you have posted a message or response,
    do not submit this request ... you are already signed up
    to receive notification!

    Your Name:
    E-Mail Address:
    Enter the correct numbers into the field below:
     

    Date of your Birth:



    Return to top of page

    Buy & Sell Exchanges | Forums | Galleries | Site Map

    FORUM GUIDELINES: Please review the guidelines below before posting at WOODWEB's Interactive Message Boards (return to top)

  • WOODWEB is a professional industrial woodworking site. Hobbyist and homeowner woodworking questions are inappropriate.
  • Messages should be kept reasonably short and on topic, relating to the focus of the forum. Responses should relate to the original question.
  • A valid email return address must be included with each message.
  • Advertising is inappropriate. The only exceptions are the Classified Ads Exchange, Machinery Exchange, Lumber Exchange, and Job Opportunities and Services Exchange. When posting listings in these areas, review the posting instructions carefully.
  • Subject lines may be edited for length and clarity.
  • "Cross posting" is not permitted. Choose the best forum for your question, and post your question at one forum only.
  • Messages requesting private responses will be removed - Forums are designed to provide information and assistance for all of our visitors. Private response requests are appropriate at WOODWEB's Exchanges and Job Opportunities and Services.
  • Messages that accuse businesses or individuals of alleged negative actions or behavior are inappropriate since WOODWEB is unable to verify or substantiate the claims.
  • Posts with the intent of soliciting answers to surveys are not appropriate. Contact WOODWEB for more information on initiating a survey.
  • Excessive forum participation by an individual upsets the balance of a healthy forum atmosphere. Individuals who excessively post responses containing marginal content will be considered repeat forum abusers.
  • Responses that initiate or support inappropriate and off-topic discussion of general politics detract from the professional woodworking focus of WOODWEB, and will be removed.
  • Participants are encouraged to use their real name when posting. Intentionally using another persons name is prohibited, and posts of this nature will be removed at WOODWEB's discretion.
  • Comments, questions, or criticisms regarding Forum policies should be directed to WOODWEB's Systems Administrator
    (return to top).

    Carefully review your message before clicking on the "Send Message" button - you will not be able to revise the message once it has been sent.

    You will be notified of responses to the message(s) you posted via email. Be sure to enter your email address correctly.

    WOODWEB's forums are a highly regarded resource for professional woodworkers. Messages and responses that are crafted in a professional and civil manner strengthen this resource. Messages that do not reflect a professional tone reduce the value of our forums.

    Messages are inappropriate when their content: is deemed libelous in nature or is based on rumor, fails to meet basic standards of decorum, contains blatant advertising or inappropriate emphasis on self promotion (return to top).

    Libel:   Posts which defame an individual or organization, or employ a tone which can be viewed as malicious in nature. Words, pictures, or cartoons which expose a person or organization to public hatred, shame, disgrace, or ridicule, or induce an ill opinion of a person or organization, are libelous.

    Improper Decorum:   Posts which are profane, inciting, disrespectful or uncivil in tone, or maliciously worded. This also includes the venting of unsubstantiated opinions. Such messages do little to illuminate a given topic, and often have the opposite effect. Constructive criticism is acceptable (return to top).

    Advertising:   The purpose of WOODWEB Forums is to provide answers, not an advertising venue. Companies participating in a Forum discussion should provide specific answers to posted questions. WOODWEB suggests that businesses include an appropriately crafted signature in order to identify their company. A well meaning post that seems to be on-topic but contains a product reference may do your business more harm than good in the Forum environment. Forum users may perceive your references to specific products as unsolicited advertising (spam) and consciously avoid your web site or services. A well-crafted signature is an appropriate way to advertise your services that will not offend potential customers. Signatures should be limited to 4-6 lines, and may contain information that identifies the type of business you're in, your URL and email address (return to top).

    Repeated Forum Abuse: Forum participants who repeatedly fail to follow WOODWEB's Forum Guidelines may encounter difficulty when attempting to post messages.

    There are often situations when the original message asks for opinions: "What is the best widget for my type of shop?". To a certain extent, the person posting the message is responsible for including specific questions within the message. An open ended question (like the one above) invites responses that may read as sales pitches. WOODWEB suggests that companies responding to such a question provide detailed and substantive replies rather than responses that read as a one-sided product promotion. It has been WOODWEB's experience that substantive responses are held in higher regard by our readers (return to top).

    The staff of WOODWEB assume no responsibility for the accuracy, content, or outcome of any posting transmitted at WOODWEB's Message Boards. Participants should undertake the use of machinery, materials and methods discussed at WOODWEB's Message Boards after considerate evaluation, and at their own risk. WOODWEB reserves the right to delete any messages it deems inappropriate. (return to top)


  • Forum Posting Help
    Your Name The name you enter in this field will be the name that appears with your post or response (return to form).
    Your Website Personal or business website links must point to the author's website. Inappropriate links will be removed without notice, and at WOODWEB's sole discretion. WOODWEB reserves the right to delete any messages with links it deems inappropriate. (return to form)
    E-Mail Address Your e-mail address will not be publicly viewable. Forum participants will be able to contact you using a contact link (included with your post) that is substituted for your actual address. You must include a valid email address in this field. (return to form)
    Subject Subject may be edited for length and clarity. Subject lines should provide an indication of the content of your post. (return to form)
    Thread Related Link and Image Guidelines Thread Related Links posted at WOODWEB's Forums and Exchanges should point to locations that provide supporting information for the topic being discussed in the current message thread. The purpose of WOODWEB Forums is to provide answers, not to serve as an advertising venue. A Thread Related Link that directs visitors to an area with inappropriate content will be removed. WOODWEB reserves the right to delete any messages with links or images it deems inappropriate. (return to form)
    Thread Related File Uploads Thread Related Files posted at WOODWEB's Forums and Exchanges should provide supporting information for the topic being discussed in the current message thread. Video Files: acceptable video formats are: .MOV .AVI .WMV .MPEG .MPG .MP4 (Image Upload Tips)   If you encounter any difficulty when uploading video files, E-mail WOODWEB for assistance. The purpose of WOODWEB Forums is to provide answers, not to serve as an advertising venue. A Thread Related File that contains inappropriate content will be removed, and uploaded files that are not directly related to the message thread will be removed. WOODWEB reserves the right to delete any messages with links, files, or images it deems inappropriate. (return to form)
    Sponsors
    • EX-FACTORY
      Importer and Dealer of New and Used Woodworking Machinery
    • Apollo Sprayers Inc.
      High Volume Low Pressure Spray Systems
    • SAMES KREMLIN formerly EXEL North America
      Precision Spraying Solutions From Pumps To Complete Application Systems-Design and Manufacture of Process Equipment Including Airspray, Airmix, Airless, Rexson Dispense, Electrostatic and Powder Coat
    • Carter Products
      Band Saw Guides, Blades, Wheels, Tires, Line Lasers and 2D Projectors, Wide Belt Sanding Accessories, Vacuum Holding Systems and More
    • Simantech
      New & Used Machinery, Supplies, Tooling, Parts, and Abrasive Products
    • Unique Machine & Tool
      Industrial Machinery for Door and Drawer Production
    • Supergrit Abrasives
      Industrial Quality Abrasives Manufactured by Leading US and Foreign Companies

    Become a Sponsor today!