Sanding bondo between slate joints

Currently, no reputable organization exists to offer a certification to pool table installers and technicians. As such, this forum is littered with DIYers, which may not have the proper background to offer good advice.

In the past, there used to be a requirement of such DIYers to preface each post with "I am not a pool table mechanic (technician), but..." This certainly gives readers an idea of how they want to interpret the advice given. Some ideas are great. Others are terrible.

That said, if wax is installed properly, it should never chip or break away from the slate. It just won't happen, no matter what.

Plaster is a horrible product to use, despite its history in this business, because it has a tendency to chip and flake.

Bondo is commonly used for a few reasons:
  • It bonds well to the slate, creating a stronger joint than wax
  • It will fill holes in the slate, which could be used as a permanent repair
  • It sands quickly and easily, which could be argued as being less messy than wax
  • It does not require the use of a torch
  • It won't drip through the seam, and onto the customer's floor
  • It is harder than wax

Despite all of the reasons that I've laid out, I still prefer to use wax. I am quite proficient with using it, it does quite a satisfactory job, and I use the proper care when installing it.
 
bradsh98 said:
No.....

Slate sands quite easily with 100 grit paper.

Brunstone does not.

If I had to guess, your table may be a Brunstone table. Hence the reason it did not damage the 'slate', when you sanded it.



If you layed it down too thick, you may want to start with a rasp. Then, you can knock it down with 80-100 grit. Once you get it close, you can use a marker to draw lines across the slate and Bondo. Continue sanding, ensuring that you are not removing the lines that you drew on the slate. Use a long straight edge, to make sure that the seams are flat (lay it across the seams, and check for daylight underneath).
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I can tell you for sure, drilling Brunstone is like drilling a hole in butter compared to drilling real slate, so it's not harder than slate.
 
realkingcobra said:
I can tell you for sure, drilling Brunstone is like drilling a hole in butter compared to drilling real slate, so it's not harder than slate.
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Not this argument again.....

Take some 80 grit and try sanding some Brunstone.. Then try to sand some slate... Tell me which one develops the bigger pile of dust..

Or, try scraping either one with a utility blade. Tell me which one scrapes easier..
 
bradsh98 said:
Not this argument again.....

Take some 80 grit and try sanding some Brunstone.. Then try to sand some slate... Tell me which one develops the bigger pile of dust..

Or, try scraping either one with a utility blade. Tell me which one scrapes easier..
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Drill a rail bolt hole in a brunstone playing surface, then drill the same size hole in Brazilian slate....then report back with your results.
 
realkingcobra said:
Drill a rail bolt hole in a brunstone playing surface, then drill the same size hole in Brazilian slate....then report back with your results.
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Not disputing that Brunstone DRILLS easier... BUT, the conversation is about SANDING, NOT DRILLING.
 
i've had it "chip-out" when my table was installed by a pro and then chip out several times after that when i redid it myself.... wax was ok before the invention of the vacuum cleaner. that's when you will have problems with the wax getting sucked out of the seam. i found that it's more of an issue if the table is cold. i began vacuuming trying not to go over the seam but that's a pain.... if you go with wax it's harder to switch to bondo because the wax must be fully removed with solvent or the bondo won't stick. bondo also protects the edges of the slate from those ball bouncing 9ball breaks.

if you like wax and haven't had any problems that's fine. i'm not saying that you are wrong but as long as bondo is available, IMHO there is no reason to use wax.
 
What is the hardness of Slate?

Slate is made up of parallel foliated plates. This gives it the ability to break smoothly and evenly along its cleavage. The hardness of rocks and minerals is measured using the Mohs scale, which ranges from one to 10 with one being the softest and 10 being the hardest. Slate ranks at*5.5*on the Mohs scale.Apr 24, 2017



Is Sandstone hard or soft?

Silica cemented*sandstone*is very durable and*hard. Calcite cemented*sandstone*is subject to acidic dissolution and is more easily eroded. Clay and gypsum cements, which are*soft*minerals, tend to produce much softer*sandstone*and the sand can sometimes be rubbed off in a person's hands
 
Is Sandstone hard or soft?
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yes, there is more inconsistency with sandstone than slate. Sandstone is a sedimentary rock and slate a metamorphic rock. there are instances where sandstone is geothermically heated and pressurized producing a stone called Quartzite but i don't know if this would be good for a pool table. . there are good reason they use slate and not sandstone and inconsistency is probably one. i just searched for "quartzite slab" and the resulting images -unlike slate- vary dramatically probably depending upon original composition and the amount of metamorphic change.

as far as drilling vs sanding. drilling sandstone might be easier because the grains of sand break loose from the matrix making drilling faster. drilling slate will produce more powder and so the drill bit might not bite as hard on every turn. Sanding on each might differ greatly with different sandpaper grit for the same reason as drilling. a fine sandpaper on sandstone might not break the grains loose as easily... . Quartz is 7 on the mohs hardness scale if i recall correctly but sandstone is a matrix of sand stuck together so you really aren't drilling the Quartz itself, you are just dislodging the quartz grains.

i was a geology major in college so i do have some scientific knowledge of these rocks.
 
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realkingcobra said:
What is the hardness of Slate?

Slate is made up of parallel foliated plates. This gives it the ability to break smoothly and evenly along its cleavage. The hardness of rocks and minerals is measured using the Mohs scale, which ranges from one to 10 with one being the softest and 10 being the hardest. Slate ranks at*5.5*on the Mohs scale.Apr 24, 2017



Is Sandstone hard or soft?

Silica cemented*sandstone*is very durable and*hard. Calcite cemented*sandstone*is subject to acidic dissolution and is more easily eroded. Clay and gypsum cements, which are*soft*minerals, tend to produce much softer*sandstone*and the sand can sometimes be rubbed off in a person's hands
Click to expand...

Enough of this quibbling..

I've never measured the hardness of either. Never had a need to. Don't care enough to worry about it, as it really doesn't make a difference.

My knowledge of the two comes from directly working with both.
 
bradsh98 said:
Enough of this quibbling..

I've never measured the hardness of either. Never had a need to. Don't care enough to worry about it, as it really doesn't make a difference.

My knowledge of the two comes from directly working with both.
Click to expand...

And I have 36 years of working with both:rolleyes:
 
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