Have you seen my no sag router table top!

[Thomas Hotchkin]

I was tired of having to deal with my MDF router table top constantly having a slight sag. I guess the PC 3.5hp was just too much weight for it. On a recent Craig's list posting, I found a Powermatic 26 shaper table top, quite inexpensive, and now I do, indeed, have a no sag table top! I added the Formica edges to make it the same size as previous top. Now I have a nice 7 in hole to easily change bits.
Tom

243161243160243159

[mreza Salav]

That's very nice. How did you attach the router there?
When I was building my router table ( not long ago) I did search for such a top but nothing came along. I might at some point that upgrade if I find a cheap cast iron top.

[Randy Gillard]

I build a maple frame under the mdf. Have never seen any evidence of sag.

[johnny means]

I've got an old shaper top that I want to do the same thing with. The problem for me is that the underside of the top is roughly cast and webbed. Was yours like this? If so, how did you mount your router? Pics?

[Thomas Hotchkin]

Mreza and Johnny
Powermatic Shaper top was predrilled with three holes that did not match my PC router, and the under side was roughly cast and webbed, like Johnny's. A friend Bridgeport made quick work of the rough surface, parallel to the top surface to less then .001. With pointed set screws screwed into the cast iron top, I was able to center my router base on the new machine surface, over the factory opening. Then I drill new holes in my router base a little larger then the bolts holes to give a little room to recenter router when I was finished. Tom

[Bill White]

To paraphrase a line from Butch and Sundance, "Think ya got a heavy enough top there Thomas?"
Well done.
Bill

[Lornie McCullough]

Hi Thomas

I saw that Craigslist shaper cabinet, and I agree it was a great price. You put it to great use!!

I made my router table using a 1950's era Mooradian table saw that had a 31"x34" aluminum top. I am surprised more people don't do this.

Lornie 243247

[Thomas Hotchkin]

Lornie
Nicely done. Good to save old aluminum from going to china. I had not heard of Mooradian manufacturing before, thanks. Tom

[jim gossage]

Don't assume that phenolis is flat, despite the ads that usu say "dead flat". I bought a jessem phenolic and it was crowned 0.025". I complained and they sent another that was crowned 0.015". I plan to build a new table w mdf and a stout ash frame underneath to hopefully prevent sagging.

[Moses Yoder]

I don't believe anything is dead flat. Since the earth is circular, the gravity would always pull the ends down more than the middle. The only way to make something dead flat would be to put a large enough cube in space that it would have a definite gravitational pull, move it far enough away from every other gravitational pull so as they wouldn't interfere, then cast a liquid that turns into a solid. I think that would be flat.

[Shawn Pixley]

Actually, following your logic, the ends being slightly further from the center of the earth than the center would have a slightly lower gravitational force on it. This of course can be measured (largely using optical lever techniques), but for our purposes is irrelevant.

The real definition would be planer or flat vs. level. Because gravity is a weak force, until the scale is reasonably great (Mass and/or length) typically the internal forces of the object dwarf those of gravity. Otherwise we would have six inch 4/4 boards that would be flat laying on a table but bent when tipped to 45 degrees.

Too your point, there is nothing dead flat. At a certain point, the fineness of the surface will be come relevant to whether the object is actually a plane or not. But this then will create one of the great sharpening discussions and those related to the fineness of the crystaline structure of the steels. I am still thinking about your plane in space example. That might be true if:

The object was absolutely pure and was allowed to to form its crystaline structure free from impurities. The crystal would have to be an ordered crystal (using the physicist definition of a crystal). That formed large ordered "sheets".
There were absolutely no forces that could be imposed (gravity, light energy, etc...). I have not thought of how dark matter or dark energy would fit into this.

The problem will also need to address the sheer fact of measuring something at these scales changes the data. But we should strive to keep ourselves from a quantum mechanics discussion here. We'd start with the Bohr / Einstein debate, and end up debating Shroedinger's cat. Without more coffee, i'd lose interest soon...and tape toast to the cat.

To the OP, nice work. Sorry for the hijack.


I don't believe anything is dead flat. Since the earth is circular, the gravity would always pull the ends down more than the middle. The only way to make something dead flat would be to put a large enough cube in space that it would have a definite gravitational pull, move it far enough away from every other gravitational pull so as they wouldn't interfere, then cast a liquid that turns into a solid. I think that would be flat.

[Bill White]

Are we waxing a bit esoterically?
My top made from sink cutouts, using a phenolic plate from Lee Valley is "flatter than a flitter".
Now that's flat (I think). :)
Bill

[glenn bradley]

That looks great. Nice re-purposing of the shaper top.


I build a maple frame under the mdf. Have never seen any evidence of sag.

For those who have MDF tops, don't give up hope. As Randy states, a well supported an MDF top will give good service. My top has had a 3.5HP router in a PRL-v1 lift hanging from it for years (15 - 18 lbs maybe) without issue. Mine is something like this:

290885

The support ribs are about 3" tall (on edge), doulbed 3/4" plywood.

[Moses Yoder]

My dad told me that college was a complete waste of my time and if I attended I would certainly end up in hell. Here now is a fine example of how a college education can be put to practical use; if I would have had this in the day, I would not be so ignorant today. Just wanted to say well done.


Actually, following your logic, the ends being slightly further from the center of the earth than the center would have a slightly lower gravitational force on it. This of course can be measured (largely using optical lever techniques), but for our purposes is irrelevant.

The real definition would be planer or flat vs. level. Because gravity is a weak force, until the scale is reasonably great (Mass and/or length) typically the internal forces of the object dwarf those of gravity. Otherwise we would have six inch 4/4 boards that would be flat laying on a table but bent when tipped to 45 degrees.

Too your point, there is nothing dead flat. At a certain point, the fineness of the surface will be come relevant to whether the object is actually a plane or not. But this then will create one of the great sharpening discussions and those related to the fineness of the crystaline structure of the steels. I am still thinking about your plane in space example. That might be true if:

The object was absolutely pure and was allowed to to form its crystaline structure free from impurities. The crystal would have to be an ordered crystal (using the physicist definition of a crystal). That formed large ordered "sheets".
There were absolutely no forces that could be imposed (gravity, light energy, etc...). I have not thought of how dark matter or dark energy would fit into this.

The problem will also need to address the sheer fact of measuring something at these scales changes the data. But we should strive to keep ourselves from a quantum mechanics discussion here. We'd start with the Bohr / Einstein debate, and end up debating Shroedinger's cat. Without more coffee, i'd lose interest soon...and tape toast to the cat.

To the OP, nice work. Sorry for the hijack.

[johnny means]

I don't believe anything is dead flat. Since the earth is circular, the gravity would always pull the ends down more than the middle. The only way to make something dead flat would be to put a large enough cube in space that it would have a definite gravitational pull, move it far enough away from every other gravitational pull so as they wouldn't interfere, then cast a liquid that turns into a solid. I think that would be flat.

?:confused:?

Your theory assumes that every shape on earth is effected by gravity in a similar manner. Surely, there are things on earth that are rigid enough not to sag under our relatively weak gravitational pull. Also your cube theory is flawed. Gravity pulls towards an objects center. Any fluid material being pulled in by gravity is going so tend towards a spherical form. The liquid on your theoretical cube would flow out into a spherical cap with the cubes gravitational center being your sphere's center point.

[Rich Riddle]

That's a great idea. The next time I need another router table top, that looks like the best choice.

[Rick Potter]

Suggestion....Why look for a shaper top? There are a lot of old rusty 3 phase shapers out there for scrap money. A lot easier finding a complete junk shaper.

Rick P

[John Piwaron]

I build a maple frame under the mdf. Have never seen any evidence of sag.

Yup. I did that too.