Which Sandblasting media

[sdold]

My sandblasting cabinet has a tube that runs from inside the cabinet down alongside the suction tube, the bottom is open right next to the bottom of the suction pickup tube. I think its purpose is to supply air down at the bottom of the pickup tube so it's not just sucking on media alone. It seems to work because the feed is always steady and doesn't come in surges like my other cabinet which doesn't have this extra tube.

You might try rigging something like that up if you don't already, it might make it easier for the gun to suck up the media.

I use Aluminum oxide and it works great, but it's dusty.

Hey Mick, did you remove the tip of the paint gun? Why, for a different pattern? What was the pattern like?

[Mick40]

Sdold,

How much air runs near the pick up tube? Where does the air come from? I would love to give this a try, just need more info.

I removed the tip because I read here that it flow better out of the gun. Well I did my first two parts, one with the tip and the other without. Without worked much better. The cloud of powder was more controlable.

What gritt Aluminum Oxide did you use? I started a brass overflow tank for my Cobra and want to finish it Monday. This PC'ing thing is really fun. I have several tanks and will ebay the others if they come out as good as my first parts.

Thanks for the help, let me know more about the air tube. Sorry if I "just dont get it". I'm new to this

Mick

Don't use anything but a fine mesh on the brass... 75-80 psi will do... But for brass i use a #8 glassbead at 50-70 psi

[trsick]

Originally Posted by Mick40

Sdold,

How much air runs near the pick up tube? Where does the air come from? I would love to give this a try, just need more info.

I removed the tip because I read here that it flow better out of the gun. Well I did my first two parts, one with the tip and the other without. Without worked much better. The cloud of powder was more controlable.

What gritt Aluminum Oxide did you use? I started a brass overflow tank for my Cobra and want to finish it Monday. This PC'ing thing is really fun. I have several tanks and will ebay the others if they come out as good as my first parts.

Thanks for the help, let me know more about the air tube. Sorry if I "just dont get it". I'm new to this

Mick

Hey Mick:
If your pick up tube is only the hose that runs from the gun, might want to try this.
Cut a piece of electrical conduit or copper pipe (sized so it will fit into your pick up hose about 2"), Clamp the pick up hose on to the new pipe. This pipe should be roughly 12". Push the pipe almost all the way to the bottom of the media in the cabinet. Then about 4" - 6" above where the media in the bottom of the cabinet is mark & drill a 1/4" hole in the side of this new pipe. By your description "the media makes it all the way up to the gun" it sounds like you are picking up too much media: aka clumping/surging. The hole you put in the side of the pipe will act like a carburator / ventura. This will help the media mist thru the gun. You may need to make the hole bigger or small depending on the lift you need & the media you are using. This hole can be adjusted by covering some of the hole with eletrical tape as needed. It may take some adjusting, but it is not difficult.
Good Luck
Bob

[Mick40]

I will give the pipe method a try before I switch over to a different media. Thanks of the tip- pun intended.

You’re correct; the brass tank is soft and only has loose paint on it so I do need to be careful. I hope that the oven won’t hurt it, there have been several repairs to the tank. How long would you put this in the oven to bake, 10min?

I have to say this is a lot of fun. Despite the sand blasting issues, very smooth so far. Now I want to try "almost chrome". It was mentioned to apply this over black, anyone try this?

Thanks for all the help!

At 10-15 the powder will flow.. let it go for another 5 then yank it out then if you want hit it with a clear. I use chrome but not that type

[sdold]

Mick: trsick may be onto something there too. My extra pipe is just a second pipe, the same diameter as the pickup tube, run alongside the pickup tube. Both ends are open. The bottom is down next to the main pickup tube's bottom. Both pipes go down and end at the bottom of the hopper, right next to each other. The other end of the "extra pipe" is up above the top of the media, just below the wire mesh thing you set the parts on in the cabinet.

I think the idea is that the pickup tube sucks media, and also some air from the bottom of the extra tube. It keeps the main pickup tube from being choked off with media only.

It's a pretty simple idea but it works great.

I'll try to post a drawing:

[Mick40]

Wow, you folks are great. I gave this a try and it worked flawless!!! Sdold, thanks for the drawing!

I powder coated an overflow tank and it came out perfect.....Except, I missed a spot. Because it was hot and my booth was small spraying the other side of the part was difficult. I thought I got it all coated but nope. So I recoated the part and I apparently did not heat it enough because there was a dull spot.

Now, how should I recoat? Any prep? The 3 parts I have done were always shot while hot. If I shoot this cold do I just bake for 15min? Because the part is cold, I suspect the time needs to be longer.

Last question, what is a good silver that I can PC bolts? Want something close to chrome. Can I shoot almost chrome on a polished bolt and then just clear it?

Sorry for all the questions, maybe someday I will be able to offer help to someone else.

Thanks,
Mick

[sdold]

The questions are great, Mick, I'm learning a ton here.

One thing with Aluminum Oxide that I just learned: It eats up ceramic tips FAST! I was blasting something yesterday and I looked at the tip and it had what looked like a crack, it turned out it was completely eaten through by the media. This is only after about two weeks of use. Man, that stuff is abrasive. I better stock up on extra tips...and maybe guns!

Steve

[pickleboy]

hey guys the best tips available are made from carbide. if possible use them. they outlast ceramic and tungsten at least 3 to 1 with all abrasives.