Black Granite For outdoor memorial

[David Dustin]

A new client of mine requested I make an outdoor memorial for his father who recently passed away.

From what I read here, Absolute Black Granite engraves well and will hold up to the elements.

My client has requested as large a piece as I can get, and it is a bit of a rush as he needs to travel to the location by the 7th of November.

The largest piece I can do in my machine is 24 x 12, but the biggest I can find online is 12 x 12. Ideally If I could get one 12 x 18 I would be happy.

Thanks in advance for any help.
David

[Dave Johnson29]

The largest piece I can do in my machine is 24 x 12, but the biggest I can find online is 12 x 12. Ideally If I could get one 12 x 18 I would be happy.


Hi David,

Just a cautionary note about checking the max weight the table of your machine can support. If the lift is motor driven it may overheat lifting it.

[David Dustin]

Dave,
It would still be a relatively thin plaque type (1/2 " to 1").

Thanks for the reply,
David

[Scott Shepherd]

A 1" piece that large might be pushing the limit on the weight. If you do find it, I'd enter your Z value without it, run it until it focuses and then put the material in so there is no load on the motor.

The weight limit for tables is quite low on some models. I don't know what it is on the PLS, but I do remember seeing something in the 50lb range for another brand that had an 18" x 24" table.

http://www.lasersketch.com/catalog/index-1.htm should get you going if you can get it in time.

[David Dustin]

Steve,
I already checked there and they have some 24 x 18 (out of stock anyway) listed but not 24 x 12.

Although I guess I could just not engrave the bottom 6" (on the 24 x 18 if it were available) but I think that will look strange.

David

[Dave Johnson29]

It would still be a relatively thin plaque type (1/2 " to 1").


Oh, OK, just didn't want to see you lug a 8" thick junk in there. :D

[Dan Starr]

Try checking with your local granite countertop shop's, they usually have pieces laying around that can be picked up cheap. Also keep in mind that if the piece is for the actual gravesite, that most cemetaries have rather strict guidlines as to the markers they will allow. Most will require the granite be 4in thick.

[Bill Cunningham]

The thinnest you would want to consider is 1" .. 1/2 granite that large is going to be somewhat fragile.. Dan is correct as well, many cemetaries do have restrictions on thickness for flat mounting on the ground.. They do have lawnmowers, and anything laying flat on the ground, would have to withstand the weight of their machines without snapping into pieces.... You can also buy blank stones from most monument makers..

[David Dustin]

I just got off the phone with my client.

He says it is a private family cemetary located next to a residence so there are no worries about mowers etc.

He still likes the idea of black marble but was wondering if marble would fade if he built an airtight case for it. What say ye?

Thanks,
David

[Thad Nickoley]

There is a granite professional on this forum. I beleive her name is Brenda. I have worked at the worlds largest single location cemetery for 15 years and I do know a little bit abount Granite. If you put granite on the ground any thinner then 2 inches you should have a cement fondation. As for the granite fading...you shouldnt have to worry about it.

[David Dustin]

Will Black Marble fade in the sun?

Thanks,
David

[Scott Shepherd]

There is a granite professional on this forum. I beleive her name is Brenda.

Belinda is who is the professional.

[Thad Nickoley]

Polished granite will retain its luster for longer then you will care about even in the sun. Of course the elements will show on it and hard water will leave calcium deposits.

[David Dustin]

But what about marble?
If it is under a clear cover will it fade from the sun?

Thanks,
David

[Darren Null]

If it is under a clear cover will it fade from the sun?
Doubt it. Granite works well on it's own; with the damage coming from weathering (acid in rain, wind-blown particles etc.). If you cover it, that will just delay the weathering. Acrylic covering will go milky in sunlight eventually, glass is better, but is much less vandal-resistant.

As regards the weight problem- if you have pass-through doors, you can support marble on either side of the machine (builder's trestles or equivalent) and focus manually...that way you can do heavy stuff without knackering your table.

[Belinda Barfield]

Dustin,

Sorry about chiming in at this late hour, but better late than never. I've been off the Creek for a few days and am just now catching up.

What thickness black granite do you need? If you can use tile thickness contact G & L Marble in Atlanta (www.glmarble.com (http://www.glmarble.com)) and order an 18 x 18. If you cut slowly and use a lot of water you can probably manage a decent cut with a tile saw to the size you need. If you want 2 cm or 3 cm contact your local stone fabrication shops. Most shops have a lot of black granite sitting around. Caution, it probably won't come cheap but you may be able to convince to stone shop to swap out engraving time for stone.

The 2 cm and 3 cm granite that most stone shops work with WILL NOT accept a detailed photo well.

Unless you want to replace the marker in a couple of years, don't use marble. Even protected from other elements, black marble will discolor with sun exposure, particularly if it is dyed.

If you need further info, please feel free to contact me. As for the "professional" part, no so much so, but learning every day! :D

[David Dustin]

Belinda,
Thanks for the tips, and I am glad you chimed in.

My client can give me a little time to get this done I guess.

My machine will only handle 24 x 12 so I need to figure out how to address this..

At least now I can research finding a pre-cut piece that will accept a detailed photo.

Thanks,
David
(if my wife and I ever make it down to Savannah we'll look you up).

[Belinda Barfield]

Belinda,
Thanks for the tips, and I am glad you chimed in.

My client can give me a little time to get this done I guess.

My machine will only handle 24 x 12 so I need to figure out how to address this..

At least now I can research finding a pre-cut piece that will accept a detailed photo.

Thanks,
David
(if my wife and I ever make it down to Savannah we'll look you up).


Just for clarification I should say I haven't been able to get a good photo result using 2 cm and 3 cm granite. Others with more expertise can probably get a great result. Stone I know, lasering not so much so. The granite that we get in 2 cm and 3 cm thicknesses has a great deal of "flecking" which I've been unable to compensate for in my efforts. Hopefully others can lead you in the right direction on that.

Please do look me up if you and your wife make it down this way. A couple of Creekers have not been so charmed by Savannah, so I'm a little wary of singing her praises. Also, I'm starting to feel as if I have the plague. I read about all of these great Creeker visits, but they never happen when someone visits Savannah. I always offer, but no takers yet. I promise to shower if y'all are coming to visit. :D

[Darren Null]

I've got good results with granite (harder than marble because nobody's mentioned that bit in this thread so far) by running it through photograv on the cherry setting at 300dpi. The flecking is going to lose you some detail whatever happens, but that can be lessened somewhat by burning hard and colourfilling with white acrylic paint (car paint is good as that's pretty weather and UV proof. And cheap). If you have to have flecking -and you probably do- try to go with as dark flecks as you can find - the amount of flecking is of secondary importance...it's the contrast that makes the picture

To get the best result, you need to minimise the detail on the photo by removing the background and other distractions. Just have what's important in the image.

[Belinda Barfield]

I've got good results with granite (harder than marble because nobody's mentioned that bit in this thread so far) by running it through photograv on the cherry setting at 300dpi. The flecking is going to lose you some detail whatever happens, but that can be lessened somewhat by burning hard and colourfilling with white acrylic paint (car paint is good as that's pretty weather and UV proof. And cheap). If you have to have flecking -and you probably do- try to go with as dark flecks as you can find - the amount of flecking is of secondary importance...it's the contrast that makes the picture

To get the best result, you need to minimise the detail on the photo by removing the background and other distractions. Just have what's important in the image.


Darren,

Many engravers get great results on black granite. I do as well when I use "laserable" granite. The quality of granite used for countertops, which is what you will get from most stone fab shops, just isn't the same. The flecks are large and tend to "blow out", for lack of a better term, so that the entire fleck is removed, rather than just the small area hit by the beam. Maybe it's just the granite we get in this area. Thanks for pointing out the granite is harder than marble, much more so in fact.

[Darren Null]

I've never had a go on laserable granite. I use the countertop stuff...round here the flecks are numerous, but small and fairly evenly spread...which is what I look for when choosing a piece.

For me, the blowing out of flecks can be pretty well sorted by colourfilling as the blowing out mostly involves a burned brown colour rather than an indentation. I'm only running 10W and maybe the flecks are smaller with my local marble. Either could be it, but I've had no problems with colourfilling. Without filling, I end up with brown splodges all over the place.

[matt heinzel]

A side question. When you say color fill, do you simply rub the paint in and then wipe it off? I am going to buying some stone to engrave shortly.

[Thad Nickoley]

I dont know that much about marblel except that it is not near as tough as granite. I think that it will last but not as good as granite.

[Darren Null]

When you say color fill, do you simply rub the paint in and then wipe it off?

Yes. Methods vary with paint/inclination/what's to hand. A summary for acrylic paint (you can also use Rub'n'Buff, toner and a variety of other colourants):

IMPORTANT: Wash the dust out of the stone and allow to dry before filling. If you leave the dust in, the paint comes away easily.

Apply with:
Credit card
Pallette knife
Spraycan

Before fully dry (I prefer- some let it dry):
Remove excess with:
Turps
WD40
Cleaning alcohol

I use felt stretched around a wooden block for cleaning off the excess...felt is quite soft, tough enough to get the paint off, and is really cheap from a dressmakers in town here. The wooden block is so you're cleaning with a flat surface so you don't scoop the paint out of the holes.

How I -in particular- do it:

1) Burn picture hard

2) Throw in shower and wash dust off

3) Dry

4) Using car paint (cheap, weather and UV proof, loads of colours) I spray the area I want filled, then scrape the excess off and move the paint around if necessary with a palette knife. I immediately start cleaning with cleaning alcohol. After some elbow grease, you should end up with your picture filled and only a thin film of paint on the polished surface; with possibly a few blobby bits here and there. Then I leave it to dry for an hour or two.

Oh yes- avoid the edges if you can...it's not polished and paint there may stay permanently.

When it's dry, I come back and get rid of the blobby bits with WD40 (I'm told that turps works here, but I haven't run out of WD40 yet), which dissolves the tough bits and reduces them to a thin smear. Leave to dry again if necessary, then get the smeary bits with cleaning alcohol.

Job done.

For indoor/multicolour I use artists acrylic paint which is much softer. On with palette knife, off with cleaning alcohol.

[Ray Mighells]

Marble has a multitude of fractures by nature and a thin piece probably would not hold up to outside weather extremes over an extended period of time.

[David Dustin]

1) Burn picture hard

Does this work well with detailed images?

Thanks for the tips.

David

[Steve Clarkson]

A summary for How I -in particular- do it:



Thanks Darren....that was very helpful and descriptive.

[Frank Corker]

I guess I am one of the select few here. I dislike infill in granite unless it's for writing. For images, I never use any whitening. I guess it's personal preference.

[Darren Null]

Does this work well with detailed images?
Yep. Burn it hard enough to leave a definitive pit in the stone for the paint to sit in. Beyond a certain point, the stone just melts and there's no further advantage. If you don't burn it hard enough, you just remove the polish, so there's no real depth for the paint to sit in and colourfilling of large areas becomes quite difficult.

EDIT: Actually it works better for detailed images, because you're filling a bunch of tiny pits. It's quite easy with large areas of black in simplified graphics to scoop out the paint from the middle.

[Gary and Jessica Houghton]

As for fading, I don't have an answer. I know that marble is relatively soft and will scratch and wear over time. Marble has been highly looked down upon outside (at least that's what I've been told). When Lasersketch is out of stuff I look at their other suppliers. www.laserstonemidwest.com (http://www.laserstonemidwest.com) appears to have the piece that sketch was out of. Have you looked into the grave markers? Laserstone midwest has some. G-MHS-SB-10x16EP, 5cm Thick, (~34lbs): @$69.12 This is their numbers. These pieces are beautiful and heavy!!!!! We lasered the size smaller and it was beautiful. It was for a dog though. A separate thought, lasersketch has some tribute stands. This might be an alternative to placing directly on the ground. http://www.lasersketch.com/catalog/tributestands.htm

[Belinda Barfield]

I've posted this before, but it is worth posting again. From the Marble Institute of America . . .

http://www.marble-institute.com/consumerresources/descriptions.cfm

Marble will not hold up in any area that received acid rain, ditto for areas watered from treated water sources. Marble is also susceptible to cracking when used in an exterior setting in areas that have freeze/thaw cycles.

[Darren Null]

Was there a way of telling for sure if the marble is dyed? I can't remember.

I found some royal purple marble in the local warehouse the other day. Got to be dyed, but looked awesome...

[Belinda Barfield]

Was there a way of telling for sure if the marble is dyed? I can't remember.

I found some royal purple marble in the local warehouse the other day. Got to be dyed, but looked awesome...


Yes . . .

http://www.sawmillcreek.org/showthread.php?t=84911&highlight=test+dyed+marble

[Darren Null]

Ah, thank you. The info didn't survive my last laptop dying.

[David Dustin]

OK we have been testing on some Black Granite Pieces and have gotten some good results.

We have tried adding paint to the engraving and it works pretty well but I have read here where some coat the granite with a clear coat of lacquer paint.

Won't that chip off or peel?

Thanks,
David

[Bill Cunningham]

OK we have been testing on some Black Granite Pieces and have gotten some good results.

We have tried adding paint to the engraving and it works pretty well but I have read here where some coat the granite with a clear coat of lacquer paint.

Won't that chip off or peel?

Thanks,
David

Yup it will in time... You should use a polymer sealer on any stone when it's done.. This is the same sealer they used to seal stone used in showers and bathrooms. I get mine from H.D. A gallon is $20-$30 and smaller sizes are available.. Granite usually can be enhanced with white paint, I use Titanium white oil paint, well rubbed in.. Once it has dried for a few days, you can seal it with the polymer. Marble usually does not require whitening, it bleaches pretty white when lasered. The polymer on marble protects it from things like acids.. Even mild acid will mar marble.. I have a piece of black in the shop, that was handled by someone that had just ate a orange. The citrus acid on his fingers left perm finger marks etched on the surface.. The best test to see if what you have is 'real' marble, is the acid test.. Put a drop on the back, if you see a little bit of fizz then its marble.. No fizz? It's something else, but not marble..