- Location
- Southern ontario
Princess auto has them for 150 if i remember correctly your going to need atleast a 60 gallon compressor to keep up
Sand blasting
- Thread starter Danika
- Start date
blackacres
Regular
- Location
- Mount Hope, Ontario
When applying a coating to a surface the surface should have an anchor profile for the coating to mechanically bond to. Certain coatings have a chemical bonding agent that will bond to smooth surfaces, but most coatings require an anchor profile.
An anchor profile can be created using; abrasive paper (hand, machine), abrasive blasting and certain mechanical tools.
Think of when one paints a car, piece of furniture, etc., the first thing is to clean the surface, solvents, TSP, soap and water are typically used to clean the surface. The next step is to sand the surface, this creates a clean anchor profile. The same principles apply to re-finishing gun parts.
As mentioned above earlier, the surface should be clean and grease free, as abrasives will not remove oils/grease, they will only get driven into the steel by the blasting media. Any oil/grease remaining on the surface will result in poor coating adhesion.
Dry ice blasting will clean a surface but it will not provide an anchor profile. Glass beads are typically used to remove old surface finishes and some surface rust. Round steel shot is used to remove mil scale. Round beads/balls do not provide an angular anchor profile. As mentioned they leave a surface similar to a golf ball, small round depressions which is not an ideal surface for a coating to mechanically bond to.
Crushed walnut shell, corn cob and plastic blast media basically only clean the surface as well. They leave little or no anchor profile for a coating to bond to well.
Fine baking soda is used to blast clean surfaces and remove graffiti, but leave the original coating untouched. Large particle baking soda is used to clean surface oxide from aluminum, but the anchor profile is very fine, most likely not suitable to apply a coating. The bonus of soda blasting is the abrasive can be removed from a part by washing it. Unlike most common abrasives.
Silica sand, aluminum oxide, Blackbeauty, steel grit are all sharp angular particles. When propelled at an object they leave a sharp angular surface which is ideal for a coating to mechanically bond to.
The depth of the anchor profile can be controlled by varying the particle size and the velocity it hits the object at. When air blasting the air pressure and distance from the blast nozzle to the object can vary the profile somewhat, however, changing the particle size is the most common way used to adjust the depth of the profile.
I know that Savage arms finish their barrels using stainless steel angular grit, to obtain the slightly rough finish on their barrels. They use a wheel blast cabinet, the blast media is thrown at the objects in the cabinet using rotating wheels, no air is used to propel the abrasive.
Long story short...........................aluminum oxide would be perfect to prepare a part for coating application!
Just make sure you remove all the abrasive from any 'hang up points'. A vacuum works well. Some guys use air, but unless you have really good filters on your compressor, you can end up applying fine particles of water and oil on your freshly cleaned and blasted part.
An anchor profile can be created using; abrasive paper (hand, machine), abrasive blasting and certain mechanical tools.
Think of when one paints a car, piece of furniture, etc., the first thing is to clean the surface, solvents, TSP, soap and water are typically used to clean the surface. The next step is to sand the surface, this creates a clean anchor profile. The same principles apply to re-finishing gun parts.
As mentioned above earlier, the surface should be clean and grease free, as abrasives will not remove oils/grease, they will only get driven into the steel by the blasting media. Any oil/grease remaining on the surface will result in poor coating adhesion.
Dry ice blasting will clean a surface but it will not provide an anchor profile. Glass beads are typically used to remove old surface finishes and some surface rust. Round steel shot is used to remove mil scale. Round beads/balls do not provide an angular anchor profile. As mentioned they leave a surface similar to a golf ball, small round depressions which is not an ideal surface for a coating to mechanically bond to.
Crushed walnut shell, corn cob and plastic blast media basically only clean the surface as well. They leave little or no anchor profile for a coating to bond to well.
Fine baking soda is used to blast clean surfaces and remove graffiti, but leave the original coating untouched. Large particle baking soda is used to clean surface oxide from aluminum, but the anchor profile is very fine, most likely not suitable to apply a coating. The bonus of soda blasting is the abrasive can be removed from a part by washing it. Unlike most common abrasives.
Silica sand, aluminum oxide, Blackbeauty, steel grit are all sharp angular particles. When propelled at an object they leave a sharp angular surface which is ideal for a coating to mechanically bond to.
The depth of the anchor profile can be controlled by varying the particle size and the velocity it hits the object at. When air blasting the air pressure and distance from the blast nozzle to the object can vary the profile somewhat, however, changing the particle size is the most common way used to adjust the depth of the profile.
I know that Savage arms finish their barrels using stainless steel angular grit, to obtain the slightly rough finish on their barrels. They use a wheel blast cabinet, the blast media is thrown at the objects in the cabinet using rotating wheels, no air is used to propel the abrasive.
Long story short...........................aluminum oxide would be perfect to prepare a part for coating application!
Just make sure you remove all the abrasive from any 'hang up points'. A vacuum works well. Some guys use air, but unless you have really good filters on your compressor, you can end up applying fine particles of water and oil on your freshly cleaned and blasted part.
Griffin6869
CGN Regular
- Location
- Cloverdale, BC
Great info Blackacres
