Sandblasting letters .. On Granite.. like Tombstone question

[Marctrees]

Hey all.. new here.. exploring a possibility for part time Pet grave marker market...

I am wondering if anyone has sandblasted lettering onto either polished Granite or other stone using a rubber mask on the stone.

My question is limited to... will I make decent although slow progress w a true 5 hp comp, typical 100 lb pressure pot, and Black diamond abrasive?

Like doing a very small simple Tombstone.

Name, dates... simple and small.

I know all bout my limited CFM..

I have done a few vehicle frames, BBQ pits, no problem...

My question is about will my equip cut decently into polished Granite w some 3D affect more than Etching.

I know Granite is harder than many other stones.

Do I HAVE to move up to more expensive like AL Oxide or similar ?

Or will the cheap available Black Beauty slag stuff work?

I want to get like somewhat 3D, not just "Etched"

Hoping on cutting total depth maybe 1/16" minimum w multiple passes.

Can I do it w the equipment I have listed if it is a hobby w more time than money .....not production ?

Obviously, I wish I had a huge trailer comp driven high cfm and appropriate pot, but I don't.

I guess summed up I am asking if my rig will do deeper cutting than just surface etching

I do expect slow progress and multiple slow passes... but this is just to start out.. not yet production.

My blasting rig is remotely stored away, otherwise I would just try this.



Thank you all very much !!! Marc

 

[bowtievega]

If the volume is low you should be ok. We used to do alot of sandblasted tile and granite back in the day. Used a 100 lb hopper and black copper slag media for the longest time. We have an enclosed booth now and run aluminum oxide as it get recycled and lasts much longer. The biggest issue you will have is your limited CFM with the 5hp compressor. When the weather is warm that air is going to be hot and you will start to have issues with moisture clogging your sand feed. Eventually we switched to a 10 hp compressor and still had issues with CFM but we were blasting 8 hours a day when we had big jobs. During our monsoon season when the humidity jumped up we definately had issues with moisture.

 

[Russ Aubertin]

Black Beauty won't work as it is only coal slag and too soft to cut stone efficiently. I use a local monument company to do the actual sandblasting. They use steel shot with high cfm and relative pressure. For etching you can use Aluminum Oxide. If you provide the stone with the mask applied you will need to use an additional adhesive called a filler to hold up to the steel shot and pressure. https://www.3m.com/3M/en_US/company...ndblast-Filler-2/?N=5002385+3293194311&rt=rud There are other brands available other than 3m. If you don't want to invest in all this, provide the monument company with a DXF file and let them do the work. You can make a good markup doing this and save yourself a ton of time.

 

[James Burke]

We only do engraved stone work. As noted above, Black Beauty will not work. You'll need to use Aluminum Oxide abrasive...60 to 100 grit, depending on your stencil material. AO is costly, so make sure you have a way to contain the abrasive so you can use it again.

Doing a v-sunk (deep cut) engraving directly in a polished granite surface will not be legible. You'll need to "frost" the background to provide contrast. Skin cut letters (1/32" to 1/16" shallow cut) are best for black granite and whenever you do not provide a panel. V-sunk lettering on natural stone does not need a panel for contrast. Use a paint like Lithichrome that is specially designed for stone.

Given your air compressor size, it would be best if you blasted after the compressor has cycled off if the motor doesn't have a 100% duty cycle. Keep to a nozzle size of 1/8" or less. PM me if you need chart that explains the CFM air consumption rate for any given nozzle size.


JB

 

[Marctrees]

Even in humid TX, my moisture caking/ plugging problems been previously solved... so that is no longer an issue.

After more Googling, I'll refine my question.

If I am not "On the clock" Pro production wise...will my rig do the job?

My pump/ motor only produces like 16 cfm... BUT I can certainly drain my 60 gal pumped up to 140 lb tank quicker than the pump can re supply and then pause blasting and wait for catch up.

Meaning.. I CAN supply way more than 16 cfm for a short time... my hose to the blaster from the Comp is very short and 3/4" ID.

Again, I have time... I can wait for the rig to catch up.

So, considering all that... will I be able to cut polished granite to a decent 3D depth... like 1'16" plus ? ?

Thank you ALL again, Marc

 

[Marctrees]

At some point I will have to access my in storage not readily accessible blast setup, but I am just trying to learn if I can PROBABLY yes or no do what I am asking.

Marc

 

[Marctrees]

Another seperate question I will have ...only will matter IF my rig is sufficient... will be a recommendation for a specific masking material, method... CONSIDERING my entire situation.

Again, Thank You ALL.... Marc

 

[alexa800]

Granite is a tough stone, so achieving a 3D effect might require a more abrasive material like aluminum oxide. The cheaper Black Beauty slag could work, but it may take more time and multiple passes. With your current equipment, you can give it a shot as a hobby but expect slower progress. You can try it on Headstones Oregon; the material must fit well. I hope that helps!