Sandblasting: need some help here...

[Kenny]

I did a couple searches for sandblasting, what media to use, pressure, nozzle size, and I've not really found a whole lot (maybe I just suck using the search?)

Anyway, I have a small benchtop blast cabinet (JobSmart model#JSSBC90) that I bought for other uses, and it does work well. But, I've always used silicon carbide media in it, and I'm not sure if this is what I want to be using to blast briar? It's simply been used for rust removal when restoring old woodworking machinery, handplanes, etc. And while it's quite aggressive, I have a feeling it's not what I'm looking for when it comes to blasting briar.

Now, I've seen a few guys speak of using glass bead media, but the stuff has a pretty wide grit range (from 40 to 400 or so), and I have no real idea where I'd want to start at. And I don't want to end up spending a ton of money buying bucket after bucket of media.

I guess what I'm looking for is a basic starting point for media (I'm going to be using Algerian Briar) and nozzle size.
My compressor is a 2.5hp 28-gallon delivering 5cfm@90psi (oil-lubed) with 20 gallon expansion tank, plus I have another 1.5hp 8-gallon delivering 2cfm@90(oil-lubed) which I can also plumb into the expansion tank for a little extra "help". (we'll see if it does actually help)

I know my compressor set-up isn't ideal, but it's what I have, and I kinda need to make-do with it for now. It blasts quite well currently, so I think it should do OK. If I need to stop every few minutes to let pressure build, so be it. I'm not in a huge rush, as this is only a hobby at this point.

Any help with this is appreciated!

[Tyler]

You're into an area of pipe making where there is less information shared than others. Largely this is because blasting is not an exact science. Every block behaves differently.

I'm relatively new to blasting, but I'll offer this. Glass bead is a good choice and fine is a good direction to head. That's about all I know. I'm learning with you.

Tyler

[Sasquatch]

Yup.

Really, what you do is find what works given the setup you've got. Start with what's in your cabinet and see what happens. If it works great.... you're there. If not, you start playing.

[Ironpenny]

Buckshot for sure. Get a real deep blast.


Chris

[baweaverpipes]

Blasting is costly.
You will need a minimum of a 5hp two stage air compressor, this is the most important part of the process.
Walnut shells, baking soda, aluminum oxide, glass beads, silicon carbide and plastic are all available. I've experimented with them all. The norm is in favor of glass beads.
Don't ask Rod Davies about blasting, he's guarded about the process and his blasted pipes suck.

[KurtHuhn]

The best advice is to upgrade your compressor. You CAN blast with your 28-gallon one. It will be a slow laborious process, however. You'll need to match the jet and nozzle appropriately. You compressor will pretty much be running 100% of the time.

I would not suggest trying to plumb the two compressors together. I have no idea how they will behave, but my Ostrogoth Sense is tingling - and that usually only happens when someone (usually me) is about to do something fabulously stupid.

Beyond that, it's time to start playing with media. Since you're using a small compressor, I suggest something sharp and aggressive. White aluminum oxide is pretty good, but you have to be very careful not to blast the entire pipe smaller without a lot of detail. Keep the pressure down, and keep checking your progress. This may work for you, it may not. You might find that pre-blasting with a sharp media, then finishing with glass bead, will give you some good results. When I first started blasting, that's exactly what I used to do.

[TRS]

but my Ostrogoth Sense is tingling - and that usually only happens when someone (usually me) is about to do something fabulously stupid.

[andrew]

I'd say there is a time/place for letting someone go headlong into certain disaster, but when it involves hooking up two compressors in parallel, well we can't stand by and watch the obituaries.

Mind the Ostrogoth's tinglings... that sounds a little questionable.

[TRS]

Mind the Ostrogoth's tinglings

THAT sounds a little questionable...

[Kenny]

I'll admit, the tandem compressors isn't the safest sounding thing ever, but it's not as bad as it sounds. Lot's of places actually do this. A machine shop I worked in actually had two massive 15hp compressor pumps feeding a huge tank, something along the lines of 500gallons.
If you use check valves to eliminate any chance of a back-feed, it will work. But you don't want them "fighting each other" either, which is what the check valves are used for.
My expansion tank is rated at 500psi burst pressure, and I'll never get close to that. Hoses would let go long before that happened. And I plumbed everything with rubber hose, basically to create a weak link that will fail before anything else.

And to be honest, it's not likely I'll ever try it that way anyway. But if I get some sort of death wish, I do have a second inlet all plumbed and ready to go.

I tried some practice blasting, and the silicon carbide media seems to work quite well, and it's very aggressive! I think I'd need to do a second blast with glass to gain detail, as the silicon carbide would, as Kurt said, simply make the whole pipe smaller. But I find if I'm careful and try to follow the grain lines, it works pretty well, and my compressor isn't working too hard either.

As for the compressor, I change the oil monthly anyway. And if I do a lot of blasting, I'll just change it, daily if needed. Oil is a lot cheaper than a cooked pump! And it does have a fan I mounted on it to help keep it cool, as I knew when I bought it that it was a bit small for my needs. But, finances often dictate what can be had and what can't.

And as a final note, what in the hell is an ostrogoth?

[baweaverpipes]

I tried some practice blasting, and the silicon carbide media seems to work quite well, and it's very aggressive! I think I'd need to do a second blast with glass to gain detail, as the silicon carbide would, as Kurt said, simply make the whole pipe smaller. But I find if I'm careful and try to follow the grain lines, it works pretty well, and my compressor isn't working too hard either.

Unless you know what you're doing, silicone carbide is a very bad idea. It is much too aggressive and you will NOT get the definition you were looking for. Stick with the glass beads.
Again, don't ask Rod Davies about blasting!

[Kenny]

I tried some practice blasting, and the silicon carbide media seems to work quite well, and it's very aggressive! I think I'd need to do a second blast with glass to gain detail, as the silicon carbide would, as Kurt said, simply make the whole pipe smaller. But I find if I'm careful and try to follow the grain lines, it works pretty well, and my compressor isn't working too hard either.

Unless you know what you're doing, silicone carbide is a very bad idea. It is much too aggressive and you will NOT get the definition you were looking for. Stick with the glass beads.
Again, don't ask Rod Davies about blasting!

I had Kurt tell me to use something aggressive, and Sas said to use what was in it, so I gave it a go. And honestly, after a few hours of playing around, it's not turning out too bad. Anyway, like I said, I was just playing around to see how it worked out. I wasn't blasting a finished pipe I had spent hours working on, just some excess scrap chunks and several other different types of wood.

Anyway, I have a bunch of handplanes and some table-saw parts from a customer's machine I'm restoring to blast later, and I don't feel like cleaning out my cabinet just to goof off and then put the silicon carbide back in. And I sure don't want to be using dirty glass with rust, paint and powder-coat in it to blast a pipe.

I have glass, and I plan to try it. I'll post some pictures once I get a pipe made and try blasting it.

[KurtHuhn]

And as a final note, what in the hell is an ostrogoth?

That's Ostrogoth. Note the capital "O".

If you closely in the image below, you may notice him in a very unnatural environment (a city) attempting to remain inconspicuous.

[d.huber]

Wow, Kurt. You're a star!

[Alan L]

See, you can even recognize one without the characteristic assless chaps or oil-lubed lederhosen by looking at the low, criminal forehead, occipital bun, and beetling brow ridge suggestive of neanderthal ancestry. Ostrogoths (from the Latin, eastern goths, not to be confused with the Visigoths) sacked Roman Spain and North Africa between around 500-600 AD.

Now sadly reduced in number, the remaining few wander the earth seeking to set right centuries of oppression by promoting the use of tobacco in handcrafted pipes of excellent workmanship, often armed with hand-forged cutlery.

The chaps and lederhosen hearken back to their ancestral home in northern Europe, and were at one time often accompanied by tyrolean hats, but those have sadly fallen by the wayside as they seek to remain hard to detect to those unaware of their glorious history. There is said to be a small enclave of them in Rhode Island, as the photo above suggests.

Should you be lucky enough to meet one, it is customary to offer rope tobacco and dark beer as a peace offering.

[caskwith]

And as a final note, what in the hell is an ostrogoth?

That's Ostrogoth. Note the capital "O".

If you closely in the image below, you may notice him in a very unnatural environment (a city) attempting to remain inconspicuous.

The one on the far right with the pink crocs, right?

[KurtHuhn]

See, you can even recognize one without the characteristic assless chaps or oil-lubed lederhosen by looking at the low, criminal forehead, occipital bun, and beetling brow ridge suggestive of neanderthal ancestry. Ostrogoths (from the Latin, eastern goths, not to be confused with the Visigoths) sacked Roman Spain and North Africa between around 500-600 AD.

Now sadly reduced in number, the remaining few wander the earth seeking to set right centuries of oppression by promoting the use of tobacco in handcrafted pipes of excellent workmanship, often armed with hand-forged cutlery.

The chaps and lederhosen hearken back to their ancestral home in northern Europe, and were at one time often accompanied by tyrolean hats, but those have sadly fallen by the wayside as they seek to remain hard to detect to those unaware of their glorious history. There is said to be a small enclave of them in Rhode Island, as the photo above suggests.

Should you be lucky enough to meet one, it is customary to offer rope tobacco and dark beer as a peace offering.

ROFL!! That is as apt a description of me as any I've ever read.

[Hudson]

[Alden]

Damn, you aint right .

[Kenny]

How the hell did this come from sandblasting?