Resurface Slate Bed

[fendrboard]

Hi mechanics, looking for information on resurfacing a 9ft slate bed. I hear it’s doable but unsure about the details. I feel as if my table has some slight imperfections and a resurface might do the trick. I’ve asked local installers, the one who said they can do it vanished. One individual i spoke with stated using a decently weighted granite leveling block with some sandpaper (100 grit) attached is a good method. Ensure the table is level before starting. Place chalk marks on the slates (3 piece), use the granite block in figure 8 patterns single pass over the slate. Rinse and repeat until all chalk marks disappear. Do not push down on the block, let it do the work. Is this a good approach? Is there any tutorial available to follow as a guide? Any guidance is appreciated. A recommendation for a good mechanic in Bakersfield CA would also work.

Regards,
VS

 

[rexus31]

Hi mechanics, looking for information on resurfacing a 9ft slate bed. I hear it’s doable but unsure about the details. I feel as if my table has some slight imperfections and a resurface might do the trick. I’ve asked local installers, the one who said they can do it vanished. One individual i spoke with stated using a decently weighted granite leveling block with some sandpaper (100 grit) attached is a good method. Ensure the table is level before starting. Place chalk marks on the slates (3 piece), use the granite block in figure 8 patterns single pass over the slate. Rinse and repeat until all chalk marks disappear. Do not push down on the block, let it do the work. Is this a good approach? Is there any tutorial available to follow as a guide? Any guidance is appreciated. A recommendation for a good mechanic in Bakersfield CA would also work.

Regards,
VS

What kind of table?

 

[muskyed]

I would think it might be cheaper to just buy some new slate. Or if a Gold Crown, maybe just buy a junk table for the slate and throw the rest away. Sanding in such a way as you describe would work, but be very time consuming and you would have to be really careful to not over sand the center. Not sure where you are going to find a piece of flat granite at least 2-3' long as much less than 2' will just follow the highs and lows. Then there is the problem that a long piece just won't cut well as there won't be enough pressure per sq inch.
Keep in mind that granite will flex and that a piece 2' or 3' long by 6" or so would also'
If it's just a few high spots, I would think that easily could be done.

 

[Renegade_56]

I fail to see what the point of this is honestly. What are you trying to accomplish?

 

[3kushn]

You should watch the whole video but start at 17:40 to get an idea of the pattern.
These guys are calibrating a granite surface plate used in a metrology lab where near perfect is required.

 

[fastone371]

You should watch the whole video but start at 17:40 to get an idea of the pattern.
These guys are calibrating a granite surface plate used in a metrology lab where near perfect is required.

Same video as above but with time stamp to start video in appropriate place for pertinent info.

 

[fendrboard]

Thanks for the responses, this is a Brunswick gold crown. I've been looking for used slates but there aren't any in my area and sourcing one remotely has been difficult. I wanted to resurface to get some of the imperfections out, I can see they exist with a straight edge without the cloth on. Are they crazy bad, no, but is it bothering me, yes. I've considered new slates but they are expensive and a last resort if any. Figured I would try a resurface first, if it fails I can get new slate. @fastone371 and @muskyed, thank you for the posts.

Regards,
VS

 

[fendrboard]

Same video as above but with time stamp to start video in appropriate place for pertinent info.

Exactly what I needed, thank you so very much.

Regards,
VS

 

[Ssonerai]

Not sure where you are going to find a piece of flat granite at least 2-3' long as much less than 2' will just follow the highs and lows. Then there is the problem that a long piece just won't cut well as there won't be enough pressure per sq inch.
Keep in mind that granite will flex and that a piece 2' or 3' long by 6" or so would also'
If it's just a few high spots, I would think that easily could be done.

Here's one at 50" for a decent price. (click on the 2000 mm version for $459. Can't get the link to go directly)

https://www.aliexpress.us/item/3256805452159732.html?src=google&pdp_npi=4%40dis%21USD%21126.49%21119.63%21%21%21%21%21%40%2112000035860909944%21ppc%21%21%21&src=google&albch=shopping&acnt=708-803-3821&isdl=y&slnk=&plac=&mtctp=&albbt=Google_7_shopping&aff_platform=google&aff_short_key=UneMJZVf&gclsrc=aw.ds&albagn=888888&ds_e_adid=&ds_e_matchtype=&ds_e_device=c&ds_e_network=x&ds_e_product_group_id=&ds_e_product_id=en3256805452159732&ds_e_product_merchant_id=758561447&ds_e_product_country=US&ds_e_product_language=en&ds_e_product_channel=online&ds_e_product_store_id=&ds_url_v=2&albcp=19623912707&albag=&isSmbAutoCall=false&needSmbHouyi=false&gad_source=1&gclid=Cj0KCQiA0fu5BhDQARIsAMXUBOIEQfwhdZwR6tOmpRYnhbFewXURGLA4cBBIm7ykyjqVEZplmxA5pWsaAvJrEALw_wcB&gatewayAdapt=glo2usa

OTOH, the shipping is a killer. Plus will it arrive in one piece????



I used to make and sell 31" CI versions, & have several from 30" through 72" long. Sold my 8 footer since i got too old to lift it anymore.
On slate, another way to use them is to spot and scrape (with carbide scraper) the offending high spots. Just like scraping/rescraping machine ways.

Time consuming, but accessible.

The risk with a wood framed table, is how close to work? Good today, and all wonky as it settles tomorrow; or when the weather changes.
Be very confident of your initial set up before modifying the faces. including pinning/gluing the slates. Again, just like re-scraping a large precision machine tool. But then, on the pool table, how to "dumb down" the accuracy so it is attainable all over? Like trying to use a Starrett 199 level on a pool table - it won't really work and will send you to the loony bin. You have to use the much less precision series 98- Starretts for a pool table to hope to actually make headway.

 

[rexus31]

Take your stales to a granite fabricator. They should be able to re-hone your slates more accurately. I personally think it is a wasted effort, but knock your socks off!

 

[Ssonerai]

I used to buy cast iron surface plates at auctions when the only other bidders were scrappies.
You can still find them at times (Like the lapping plate the guy is using in the video). OTOH people know about straight edges, and it is unlikely to "steal" one of those anymore. A straight edge and a "moderate size" lapping plate could make short work of a pool table. The bigger the better for the reference/lapping tools, however this has to be modified by "not so heavy you can't manage them easily, or that they change the shape of the surface you are working on due to their mass/weight.

Here is one (5' length) i'm planing straight.

Planers like these used to be used to flatten slate, before huge diamond hones were available. I watched them working in slate quarries back, still in the 1980's. But by that time the planers were used for roughing out. The matched table slates were set up on the hone for final finishing as a set. Unfortunately, my planer is not wide enough for table slates. (only 2' between columns).