What to fill hole in a Tablesaw top with?

[Mike Olson]

I have an old sears tablesaw with a yellow disc set into the top in front of the blade. Mine actually sat below the surface by about 1/8" and when I was recently ripping some long thin pieces when the end that I had the push stick on went over that disc it lifted the other end of the wood just above the saw blade and scared the heck out of me.

I pulled out the disc and found out it's a hole right through the top. The disc is not in such great condition now so I need to replace it with something else but i'm not sure If I want to use wood, or maybe plug the hole and fill with Epoxy. how hard would it be to fill with epoxy and make it flush? maybe I should just stick with a wooden plug and scrape flush with the top.

Found a picture online of what looks like the same saw showing the yellow disc.

http://www.ohio.edu/people/schneidw/audio/images/pluto_miter-018sml.jpg

Thanks,
Mike

[David Hawkins]

Wood plug probably won't last very long. If you have a Fastenall store nearby they carry a epoxy metal repair material that will sand down to a perfect match. I would stick a piece of flashing or other thin metal to the underside of the table with a little epoxy (clean with mineral spirits first) and then pour some of the liquid metal to fill the hole a little proud. When it hardens file/sand it down and buff/wax it. I have done similar repairs and it seems to last well and is not expensive should be under $20.00

[Aaron Berk]

How about melting some plastic right onto the disk, then sanding flush?

Quick and stress free.

[Dave Richards]

Is there anything under the yellow plug that you might need to get at some day? If not, I would use epoxy. I would coat the area around the hole with a thick coating of wax or paraffin making sure I don't get any in the hole, cover a small scrap of plywood with clear packing tape and wedge it up under the hole so the epoxy doesn't run out the bottom. Mix up some epoxy and put a little of it in to line the hole. Then thicken the remainder with fumed silica and put it in up to the top. don't fuss with it. Just let it cure. Check to see if you need to top off the hole with a little more epoxy and do so as needed. Then, when the epoxy is cured hard, scrap and sand it flush with the top.

[Art Mann]

I have attempted to sand silica (or wood flour) thickened epoxy in the process of building a fiberglass over plywood boat. The process is not easy. It sands about as easily as cast iron. If you go with epoxy, try to minimize the amount of leveling that needs to be done and be prepared to scratch up your cast iron top.

My suggestion is to make a thick wooden plug out of some tough wood like hickory that fits very accurately and glue that in with epoxy. If it is like my table saw (Ridgid 3650) the little plastic disk lasted a long time and it isn't nearly as tough a material as hickory or maple or oak.

[Mike Olson]

How about melting some plastic right onto the disk, then sanding flush?

Quick and stress free.

DOH!!! I just melted some pewter for a casting project last month. I'll try that. Thanks for the input.

Mike

[Dave Richards]

A card scraper works very nicely on cured epoxy. Sanding does, too if you don't overheat it.

[Stew Hagerty]

You can actually still buy those yellow discs through Sears. They were meant to be a place where you could indicate the edges of various blades & dado sets to line up your cut against. I actually replaced mine not too long ago. Go to the Sears website, tab on Parts, and type in you model number. You'll be surprised at how many components they still have available for your saw. At least I was.

[Dave Cullen]

You could also build up the underside lip with RTV or hot melt glue and press the disc back in flush. I think the disc is a very useful feature of my saw and wouldn't want to lose it.

[David Hawkins]

If you use a flat file after the epoxy cures it will flush down fairly quickly then if you wet sand with either light machine oil or mineral spirits starting with 100 grit, 180 grit, 320 grit and 600 grit the table will be fine. A little wax and you are done.

Wooden plugs in metal are subject to: metal heating/cooling, wood swelling shrinking, general vibration etc. A bone dry wood plug will pick up any humidity and could conceivably warp a metal table top since in the case of hickory the wood/water stress in on the order of 300,000 lbs per square inch. I don't know just how much it could warp (too many unknown variables) but that is the amount of pressure that could be generated.

[johnny means]

Hmmmm, many better, ie. industrial grade euro machines, sliders and bandsaws, come with wooden plugs and ZCIs. If it works for a $15,000 machine that's expected to perform well for decades, I'll bet it would work for a hobbyist's saw.

[Bruce Page]

I always thought the yellow dot was a neat feature on my old Sears TS and often wish my unisaw had one.

I would try to save it by remarking with a sharp pencil, and fill with a clear filler, scrape flat, and polish if necessary.

[jack forsberg]

Hmmmm, many better, ie. industrial grade euro machines, sliders and bandsaws, come with wooden plugs and ZCIs. If it works for a $15,000 machine that's expected to perform well for decades, I'll bet it would work for a hobbyist's saw.

+1

but what's it for?

[Art Mann]

but what's it for?

You are supposed to use a pencil to mark the position on the plastic where the wood will meet the blade before doing a rip cut. That is one possibility. It makes it easier to rip to a mark on the end of the wood. I used it that way a time or two but then forgot about it.

[Art Mann]

Before using the silica thickened epoxy for the actual application, try mixing and curing a glop on a piece of plywood and then try to sand that. The suggestion of using a file is not unreasonable. I used a sander/grinder with 60 grit paper to shape fillet joints and it didn't go all that quickly. Maybe other folks are using a weaker material. I used System Three epoxy, which is a standard material for boat building.

[Bruce Page]

+1

but what's it for?

I used it for mostly for cross cutting. It is a soft plastic insert a few inches in front of the blade that is meant to allow you to place a pencil mark that registers with either side of the saw kerf. It allows you to exactly align your board for cross-cuts and is very handy when you just want to take a hair off of the end of a board.

[johnny means]

I miss this little feature from my first TS. Pencil marks don't show up well on CI:(. And they don't stay put:(.

[George Bokros]

Could you put some masking tape on the under side of the plug to shim it so it is flush to the top?

[jack forsberg]

Thanks Bruce and Art
my wadkin PK has something like that that is just in front of the saw blade and i use it all the time. Its just a small space/kerf in the in-laded steel rule showing the kerf width.. I also have wood all over the top so i would use wood and not worry(something hard a light in color) for the pencil mark to show.

274439



I used it for mostly for cross cutting. It is a soft plastic insert a few inches in front of the blade that is meant to allow you to place a pencil mark that registers with either side of the saw kerf. It allows you to exactly align your board for cross-cuts and is very handy when you just want to take a hair off of the end of a board.

[Frederick Skelly]

A card scraper works very nicely on cured epoxy. Sanding does, too if you don't overheat it.

I was thinking the same thing Dave.
Fred

[David Hawkins]

Bet those are loose fit inserts not tight fit. You might also want to consider that $15k machines are more substantial than craftsman saws and that they are engineered to work with original parts.....

[Erik Loza]

A piece of white UHMW plastic? Or, just fill it with JB Weld and buff it flat if it it's not important to ever remove that piece again?

Erik Loza
Minimax USA

[Bruce Volden]

How 'bout a "knock out" from electric boxes--they have several sizes?

Bruce

[Keith Hankins]

Easy JB Weld. Use it to fill voids and dings in old cast iron and it's solid and sands flat. Tape a flat piece of hardboard over the bottom. Fill it hi, let it set and sand flat. Might take a couple tubes. But it will hold.

[Rick Potter]

Like Stew says, just get a new insert from Sears. Someone probably broke the tabs off the one you have. It should fit tightly and stay in. My dad's saw had one in it for years with no problems.

Rick Potter

[Jacob Reverb]

DOH!!! I just melted some pewter for a casting project last month. I'll try that.

I suspect that unless you get the cast iron top to the same temperature as the molten pewter, the CI will act as a heat sink, causing the pewter to harden too fast and preventing it from "bonding" to the iron or even really filling the entire hole. Think: "Cold solder joint."

I'd just use JB Weld or some other epoxy and filler and be done with it.

[Darryl Hazen]

Another vote for JB Weld.

[Dave Kirby]

What about using JB Weld?

[Larry Browning]

I suspect that unless you get the cast iron top to the same temperature as the molten pewter, the CI will act as a heat sink, causing the pewter to harden too fast and preventing it from "bonding" to the iron or even really filling the entire hole. Think: "Cold solder joint."

I'd just use JB Weld or some other epoxy and filler and be done with it.
Jacob,
I could be wrong, but I think the suggestion was to fill the hole with melted plastic. Mike was sorta saying, "Why didn't I think of that?, I had just done a project where I melted something." I don't think he was considering using pewter instead of plastic.

[Keith Hankins]

Another vote for JB Weld.

It's amazing stuff ain't it.

[Bill Huber]

I am one that think you should fix it, I have one on my Jet and use it a lot.

Now if you are pushing the wood down into it as as you cut I would say you need to get a different push stick, one that does not put so much down pressure on on the trailing end, to me that is just asking for problems.

[Phil Thien]

You could also build up the underside lip with RTV or hot melt glue and press the disc back in flush. I think the disc is a very useful feature of my saw and wouldn't want to lose it.

^^^ This.

Just remove it, add some hot-melt glue, and replace it. Use a larger board to apply even downwards pressure so it is even with the top of the saw.

[Mike Olson]

Wow lots of responses on this...

I filled the hole last night with Pewter and filed it flush with the surface of the table saw. Also gave me a chance to go over the whole surface with some 220 grit paper to take some of the rust-grime off and put a couple new layers of a spray wax from rockler for table saw tops. The Pewter is soft enough that I can easily cut a new groove into it to duplicate what the Yellow disk did but I never used it so I probably won't.

The hole:
274516

cut a piece of flashing and dropped it in to cover the hole. Also a shot of the Pewter in my ladle waiting to be melted.
274517

Poured in the Pewter, it pooled on top and I found out i can easily remove it if I want.
274518

Filed down flush with the top
274519

Worked Quite Well and basically free since it was left over from another project.

[Dave Kirby]

It's amazing stuff ain't it.

It certainly is! I've used that stuff for just about everything from metalwork to kids toys. Even replaced a golf club "9 iron" head with it one time years ago. That club is still going strong and still hits a Texas mile!!