Removing Rust from a Table Saw

      Advice on getting rust off machinery, from simple scrubbing to high-tech electrolysis. October 29, 2012

I have a Unisaw table and a Delta shaper table that sat in storage for about a year under a roof that leaked. Both pieces of equipment have significant rust with a little bit of pitting here and there. They are unusable as is, so I need to get them functional again. Can they be resurfaced? Anyone know the cost of that compared to buying a new table? Any suggestions would be appreciated. I'm pretty upset and frustrated with myself and the landlord over this.

Forum Responses
(Solid Wood Machining Forum)
From contributor S:
You can remove the rust, even if it's real bad, by a hand lapping process. First, scrape off the loose rust with a putty knife. If you have any deep gouges, drill some tiny holes in the gouge and then fill it with Liquid Steel, JB Weld, or similar. Allow the patch to fully cure before going on.

Start off with sandpaper on a 1/4 sheet palm sander. Keep the sanding wet with mineral spirits. Use whatever grit it takes. Sand for a bit, then clean the surface real well with pure alcohol or similar. Then lay a straight edge (Starret makes good ones) on the table and shine a small bright light at the gap between the straight edge and table. Mark your high spots with a grease pencil and keep sanding with extra action on the highs. When the table starts looking good and you have it figured flat, then start going to finer grits. 200, 400, 600, 800. Examine the top after each grit with a bright grazing light under a magnifier. This will reveal any remaining sanding pits. Keep checking with the straight edge for flatness.

Finally, polish the top for an extended period using a cerium oxide type polishing compound. Polish for a long time. You'll end up with a beautiful, smooth top that's flatter than new.

From contributor D:
The easiest and best method of rust removal is by electrolysis. I've done this to old antique tools found at flea markets that looked worthless, and with very little effort came out sparkling like brand new. I'm not going to go into detail here because there are many step by step tutorials all over the web.

Basically, I can see it may be some more effort in your case, but less than sanding it. You'll need to unbolt those heavy cast iron tops and set them in a large tub that they can be completely submerged in. I'm thinking a kiddie pool or the like. You hook the negative end of a battery charger to your table, and the positive to a sacrificial anode of choice, like an old piece of rebar, and do not let them touch each other. A little baking soda in the water is needed. Plug it in and leave it. The ionized rust will be bubbling toward the anode. Every now and then, unplug it and brush off loose rust with a grey scotch brite pad, and move the anode around. The bigger the anode is, the faster it works. Anyway, it will remove all the rust completely, which you really should do before filling any pitting.

I've only done this in a five gallon bucket, but I'd not hesitate to do it in your case. There are folks out there who professionally restore antique cars who've knocked up a plywood box lined with a tarp in order to soak a whole rusted car frame. Much less work than sanding through all the grits, and also does not risk removing any of the base metal, just the rust. The drawback in your case is the weight. If you don't have a cherry picker, shop crane, or at least a couple strong backs, then trying to do this alone would be a bear.

From contributor J:
Both my thicknesser and jointer had surface rust. 3M Scotchbrite and WD40 seemed to polish it up alright.

From contributor S:
Google Unisaw restoration and you'll find some really good articles on it. There's a good video series, too.

From contributor F:
Like to find out more about electrolysis. check the web for Coolerman FJ 40. It's about restoration of a Land Cruiser.

From contributor J:
I have the exact same saw with the same bit of rust and I cleaned it up quick with a little kerosene and fine steel wool. Of course all shop machinery not in regular use will develop some rust on the horizontal surfaces. Routine table-top maintenance is all part of maintaining your workshop. Anyway, don't make a federal case out of this unless you have to… Then you can dip the whole dang thing in an electrified bubbling vat, along with the FJ40. (I'm currently looking for some old junk to try this out on. This looks too good to be true.)

From the original questioner:
Mine is far worse, with some pitting. I have been cleaning it with WD-40 and a 3M pad and have been making progress. Thanks for everyone's help.

From contributor E:
If you're trying to restore it, I'd certainly dig up some info at OWWM. On the other hand, if you're looking to get the rust off and use the machine to work, I'd hit it with some WD40 and a ROS fit up with a Scotchbrite pad and get it done quick and dirty. Pitting won't affect the way the saw works, so I wouldn't worry about it.

From contributor O:
Take the four bolts off that secure the table to the cabinet and take the top to a shop with a Blanchard grinder. For just over a hundred dollars they will give you back a cast iron mirror.

From contributor N:
WD40 and a scruffy pad (Scotchbrite). Wet Scotchbrite it! Been there. It works.

Would you like to add information to this article?
Interested in writing or submitting an article?
Have a question about this article?

Have you reviewed the related Knowledge Base areas below?
  • KnowledgeBase: Knowledge Base

  • KnowledgeBase: Solid Wood Machining

  • KnowledgeBase: Solid Wood Machining: Setup and Maintenance

    Would you like to add information to this article? ... Click Here

    If you have a question regarding a Knowledge Base article, your best chance at uncovering an answer is to search the entire Knowledge Base for related articles or to post your question at the appropriate WOODWEB Forum. Before posting your message, be sure to
    review our Forum Guidelines.

    Questions entered in the Knowledge Base Article comment form will not generate responses! A list of WOODWEB Forums can be found at WOODWEB's Site Map.

    When you post your question at the Forum, be sure to include references to the Knowledge Base article that inspired your question. The more information you provide with your question, the better your chances are of receiving responses.

    Return to beginning of article.

    Refer a Friend || Read This Important Information || Site Map || Privacy Policy || Site User Agreement

    Letters, questions or comments? E-Mail us and let us know what you think. Be sure to review our Frequently Asked Questions page.

    Contact us to discuss advertising or to report problems with this site.

    To report a problem, send an e-mail to our Webmaster

    Copyright © 1996-2019 - WOODWEB ® Inc.
    All rights reserved. No part of this publication may be reproduced in any manner without permission of the Editor.
    Review WOODWEB's Copyright Policy.

    The editors, writers, and staff at WOODWEB try to promote safe practices. What is safe for one woodworker under certain conditions may not be safe for others in different circumstances. Readers should undertake the use of materials and methods discussed at WOODWEB after considerate evaluation, and at their own risk.

    WOODWEB, Inc.
    335 Bedell Road
    Montrose, PA 18801

    Contact WOODWEB

  • WOODWEB - the leading resource for professional woodworkers

      Home » Knowledge Base » Knowledge Base Article