3 piece slate warp

[afss]

Its a stanley max, says on it 0.0005in/in I can see it move when i place a piece of paper under one end of a 2 foot level. Its not easy but i can see it.
The starett #98 is what i borrowed and is way way way easier to use and definetly makes a better job, i am not argueing that point, I don't recomend trying to use the carpenters level. For shits and giggles i tired to do the first piece with it. I got it pretty damn close but it took a lot longer and with the starett it was much faster and much less agrivating.

What i need to know is what is the best way to brace my frame so that when i tighten the screws into the slate that it pulls the slate down instead of deflecting the main carry beams A&B in my sketch on page one up. I am able to take about half of the warp out of the slate but the beams are deflecting too much to get the other half. with out the slate screwed down, on a two foot level i can fit almost 3 playing cards under the level at the low point. With it screwed down with the 3rd support added between C&D its just a little more than 1 playing card but thats still too much. i checked the deflection of the main beams A&B and they are definetly deflecting when the pressure of the slate and screws starts to act on them and the wood is moving instead of the slate.

How do i best brace the beams?

 

[realkingcobra]

You are probably looking at the milling tolerance of the carpenters level? It would take 4 lines out on my Starrett 12" before you could even see the bubble moved on the 4ft carpenters level. This wouldn't be one of the blue aluminum ones from HomeDepot would it?

The Starrett #98 is a 12" level with 0.005 graduations, more than accurate enough. In fact on most slate you will only be able to get it only as level as it was manufactured. Flat is a theory in manufacturing, there is no zero.

Rob

The 98 in an 8" level

 

[n10spool]

98 is the series of that model/ style level.

Size Without Case In Finished Wood Case
Inch mm Description Catalog No. EDP No. Catalog No. EDP No.
4 100mm Without Cross Test Vial 98-4 50440
With Cross Test Vial 98-6 50441
6 150mm With Cross Test Vial, Standard Letter of Certification* 98-6 W/SLC 66935
8 200mm With Cross Test Vial 98-8 50442
With Single Plumb Vial and Cross Test Vial 98-12 50443 98Z-12 50444
12 300mm With Single Plumb Vial and Cross Test Vial,
Standard Letter of Certification* 98-12 W/SLC 66934 98Z-12 W/SLC 66933
18 450mm With Double Plumb Vial and Cross Test Vial 98-18 50445 98Z-18 50446


better view in pdf file

http://www.starrett.com/download/338_p439_444.pdf

 

[afss]

all this debate and info about the starett levels are interesting but

How do i take this warp out of the one piece of slate?

 

[ROB.M]

warp

all this debate and info about the starett levels are interesting but

How do i take this warp out of the one piece of slate?

_
_high in center?
Rob.M

 

[afss]

no, low in the center. its one of the end pieces. Low spot runs from side to side and is approximately where the holes are for the bolts that hold the rail on.

 

[afss]

Let me start by saying that i do NOT recomend this, this is only what i did and if someone reads this and choses to try it i take no liability.

Recomendations for things to do or try were slim and i tried everything i could think of for bracing the frame and trying to take the warp out of the slate. Following some good advice i got from one memeber here i found the low spot as best i could. It was more or less in a straight line from one side to the other around the middle of one piece as i orriginally put on the sketch. I drew a straight line from one side to the other and then supported that piece on some work benches in the drive way. I took a diamond circ saw blade and cut the piece in half(ish) along this line. This created a 4 piece slate table. I added an extra wood brace to put under this new joint and drilled some new holes for the screws to go into. I then leveled the table piece by piece, filled with bondo and sanded. Managed to get it down to basically a dollar bill at its worst.

I didn't want to glue the felt so i used PL premium and clamps to glue wood stapeling strips along the out side edges, took the cusions and used crazy glue to bond the few spots that they were starting to let go at. Re covered the rails and then the table. Aside from having snooker pockets at 3 1/4 inch making them harder to play pool on the balls roll true and the table plays well. I should have taken pictures but never thought to until the felt was on. Its not pretty looking from the under side with the bracing etc but it worked well for me.

Again not recomending anyone go out and cut a piece of slate and drill new holes but i couldn't figure out what to do and had nothing to lose as i figured i was going to have to buy another piece anyway.

Just thought some of you who were following this thread might want to know what happened.

 

[realkingcobra]

Let me start by saying that i do NOT recomend this, this is only what i did and if someone reads this and choses to try it i take no liability.

Recomendations for things to do or try were slim and i tried everything i could think of for bracing the frame and trying to take the warp out of the slate. Following some good advice i got from one memeber here i found the low spot as best i could. It was more or less in a straight line from one side to the other around the middle of one piece as i orriginally put on the sketch. I drew a straight line from one side to the other and then supported that piece on some work benches in the drive way. I took a diamond circ saw blade and cut the piece in half(ish) along this line. This created a 4 piece slate table. I added an extra wood brace to put under this new joint and drilled some new holes for the screws to go into. I then leveled the table piece by piece, filled with bondo and sanded. Managed to get it down to basically a dollar bill at its worst.

I didn't want to glue the felt so i used PL premium and clamps to glue wood stapeling strips along the out side edges, took the cusions and used crazy glue to bond the few spots that they were starting to let go at. Re covered the rails and then the table. Aside from having snooker pockets at 3 1/4 inch making them harder to play pool on the balls roll true and the table plays well. I should have taken pictures but never thought to until the felt was on. Its not pretty looking from the under side with the bracing etc but it worked well for me.

Again not recomending anyone go out and cut a piece of slate and drill new holes but i couldn't figure out what to do and had nothing to lose as i figured i was going to have to buy another piece anyway.

Just thought some of you who were following this thread might want to know what happened.

WHAT member on here advised cutting the slate?????????

 

[afss]

No one advised cutting the slate, No one advised anything other than shimming and that wouldn't work. The slate was not going to level and no one was offering any suggestions aside from shim so its what i decided to do. Glad i did, it worked out great.

The good advice was on how to find the low spot. It was intended to help me find the spot to shim but when shimming wouldn't remove the warp and no one was forth coming with other options i went it alone.

Like i said.. i don't recomend it as you could potentially break the slate, but given the option to have an unplayable table or risk cutting it and potentially fixing it i figured i had nothing to lose.