What to replace sand with (blasting) ?

[rclint]

I'm removing a thermal sprayed ceramic coating from aluminum, I had a cheap blaster so I got a bag of blasting sand just to see if it would work, it did, and was fast as well, left a rough surface, which I need a smooth surface. I done a few parts like this, but I don't want to mess up my lungs, so I bought a blast cabinet (no instructions, if anyone knows where I can get one for a ALC sandy blast cabinet) and have tried glass beads, and stainless cast shot, nothing will compare to the sand. The glass beads failed, the cast stainless shot is pretty slow, I mean real slow, what would be a perfect substitute for sand ? This sand that did work is also course, size of coffee grains or close, would the size of the media also have an effect ?

Thanks, Clint

[pickleboy]

probably the most aggressive media is aluminum oxide, it is also low dusting so it holds up for a good time.next best would be coal slag(black beauty).
i will pm a link for a seller of alc cabinets and you can contact them to see if they can send you instructions. best of luck bro.

[jimcarry]

Hey
how’s it going sand and bead blasting usually leaves a gray dull finish if you are looking for a bright finish after blasting try soda blasting Soda blasting is a process where a surface is cleaned, rust is removed, or coatings (of any kind) are stripped from the substrate (the surface beneath the material you are trying to remove). The soda blasting machine propels a bicarbonate-of-soda-based media via water or compressed air onto the surface to be cleaned. This process gently removes the material without harming the substrate and can be done wet or dry. There are lots of sites on line to show you how to do this
but if you can sand blast this is the same thing

[rclint]

Originally Posted by jimcarry

Hey
how’s it going sand and bead blasting usually leaves a gray dull finish if you are looking for a bright finish after blasting try soda blasting Soda blasting is a process where a surface is cleaned, rust is removed, or coatings (of any kind) are stripped from the substrate (the surface beneath the material you are trying to remove). The soda blasting machine propels a bicarbonate-of-soda-based media via water or compressed air onto the surface to be cleaned. This process gently removes the material without harming the substrate and can be done wet or dry. There are lots of sites on line to show you how to do this
but if you can sand blast this is the same thing

I'm in no way trying to say it will not work, I have never used soda (or media for that matter) blast so help me understand this


This coating is some more bad stuff, yes I want a perfectly smooth polished surface, I can deal with some amount of hand buffing, but from sand, to bead, to buffer is still a lot of work. This coating you can hold it on a buffer with a coarse wire brush, all you will see is sparks, will not touch the coating, you can buff with whatever you want to, I tried just baking soda in the blaster but it would not touch it. Do you have a soda blaster ? What would you charge me to test 3 pieces to see if it worked, I don't mind spending money if I could find something that would remove the coating, other than sand and leave me a surface ready to buff (no harsh pits etc) The cast stainless beads were $145 for 25 pounds...... I thought they would work, the do, very very slowly, I just have not hit the correct media yet I think.

Thanks, Clint

[jimcarry]

What Is Baking Soda and Corn Cob Blasting?
soda blasting is a process in which an environmentally safe product of sodium bicarbonate or ground corn cob is used as a specially formulated blast media to clean and strip most surfaces using a high volume but low pressure blasting machine. The soda serves as a mild abrasive that will remove or etch paint. Or baking soda will work as the lone, active cleaning agent for all varieties of surfaces and equipment.
The soda is dispensed from a machine (blast pot) that is specifically designed to perform the low-pressure, high volume soda or corn cob blasting operation.

This process removes paint and contaminate without harming the substrate surface. The baking soda is applied to the surface to be cleaned through a specially designed, pressurized hose and nozzle . It obtains its air pressure and air volume from a conventional shop air compressor or a mobile construction air compressor. Another variation is to use it to Wet Blast using the soda in conjunction with water. This method is used in areas where the dust generated by the blasting soda is controlled by the water. Soda blasting has many applications for removing paint, coatings, contaminants, odors and other types of cleaning on most all materials. Soda blasting can be used to clean and deodorize fire and smoke damage in buildings.

Another method of dry blasting and controlling dust is by using the magnesium sulfate. Your individual job circumstances will dictate which media is best for which job.
What are the Benefits of Soda Blasting?Soda Blasting with Sodium Bicarbonate is a nondestructive operation that can remove or prepare old paint or other materials. It will not damage most base materials or surrounding components which comprise that items body structure, i.e. steel, aluminum, fiberglass, moldings, window glass, etc.
Sodium Bicarbonate is a non-hazardous food grade material that is 100% water soluble and environmentally safe.
Soda and Corn Cob Blasting will eliminate the need for using toxic cleaning chemicals.
Soda Blasting can remove or clean multi-layered surfaces down to the level of any layer desired.
Soda and Corn Cob Blasting may be used to clean or decoat machines, while the machine is still in operation.
Baking soda as a grit blast medium offers several advantages over other solid mediums, according to the company. As each crystal of sodium-bicarbonate strikes the surface of a workpiece it crushes against the surface. When the crystal strikes a workpiece surface, the crystal is destroyed but in the process takes a bit of the soil with it.
Crystals can be sized to provide the necessary cleaning aggressiveness for an application. In part, because the baking soda crystal collapses on contact, removal problems involving getting the media from internal passages or small bores is eliminated. In addition, baking soda is water soluble therefore getting the media out of highly intricate parts is also simplified. They can be rinsed free out of the workpiece if necessary.
As a medium, baking soda is relatively soft. This makes it an effective blast medium for delicate substrates such as aluminum and thin wall sections like cylinder fins or aerospace structures. There is little or no peening action with baking soda blast. Baking soda is inert making its use and disposal less problematic than some other materials.
Cleaning work pieces and equipment is a necessity for many shops. Unfortunately there is no universal method effective for all cases. However, baking soda grit blast offers several advantages over other methods, particularly with regard to environmental and disposal considerations. That may make checking into a system for your application a good idea.—

[jrow]

One thing I might add to Jim's post, by the way it is an excellent post.

When blasting steel with soda you don't have to prime it right away. The soda leaves a coating on the steel that will last up to 2 month before the rust starts to show and you have to prime it.

John

[pickleboy]

Originally Posted by rclint

This coating is some more bad stuff, yes I want a perfectly smooth polished surface, I can deal with some amount of hand buffing, but from sand, to bead, to buffer is still a lot of work. This coating you can hold it on a buffer with a coarse wire brush, all you will see is sparks, will not touch the coating, Thanks, Clint

if its a ceramic coating of some sort, then the only way to get it off is blasting with alum. oxide, silicone carbide or other very aggressive media to remove it. there is not much you can do about the extra steps to get the polished finish you want

[BerkelUSA]

Black beauty in the fine-grade (not ultra fine) is what I have used for YEARS...

Glass bead also has great results, nice white surfaces that are as bare a steel as it gets..

This is Black-Beautys results when used the right way...

image violated terms of use and was removed

[rclint]

Just and update, aluminum oxide did remove the coating, left a pretty rough surface that I took down as much as I could with finer grades of media. I would have thought stainless steel shot would work, but it would not remove the coating either, aluminum oxide is the only thing that I tried that had any effect on it.

Hope this helps someone else.

[sofakingkool]

does anyone have some good Soda blasting links where I can find more info and purchase one?? I live in a small town and no one here can help me...Can I use a pressurized sand blaster and just use baking soda??
Thanks skk