Thread: Arboga EM825 mill/drill

OK, thanks Alan. I hunt for some soda tomorrow. I have a vibratory tumbler on the way from Israel right now (ah ebay). When it arrives I plan to try a couple of things in walnut shells...it has to be gentler than blasting.

Greg

Paid a visit to Greg's today, to experiment with bead blasting. I took over both the graduated dials from my Arboga. As mentioned above, one is rusty, the other in good nick. The one in good nick has a nice satin silver finish.

After glass bead blasting, the results were mixed. The glass certainly removed every bit of rust, and left the metal with a dull finish, but no match for the good dial.

Better than try and explain, I took a couple of snaps.

I am not sure how many PSI you have running through that gun, but there is no way I could hold a part in my hand with my gun, as it would remove skin or be very painful.
I usually get a silver glittery surface after blasting.

Dave

100 psi. Can't type...no fingertips left.

That picture was for demonstration purposes only. I keep my fingers near, but out of the blast zone.

A glove is a good idea.
I run mine at 125 PSI with the small nozzle in the gun off 2 full size compressors joined together. One is a 12 cfm and the other is a 10 cfm and they have a hard time keeping up.

Dave

PS
Don't forget to wipe the blood off your keyboard and put some band aids on those fingers.

Hi Dave.

You said you get "a silver glittery surface" after blasting. That sounds like the appearance we are after.

What sort of blast medium do you use. How far do you hold the gun away from the work, and lastly, what type or brand of gun do you use?

Ken

Mystery solved. I didn't have the nozzle inserted in the gun! Of course I was getting some small fraction of the normal velocity from the abrasive. C-47 rang me after seeing Ken's photos...I wasn't aware that the nozzle stuck so far out of the gun. I just tried it correctly: Yowie that stuff stings!

So yeah, gloves. Two pairs I think.

I have a 12 CFM and it does run almost full-time. The tank drain was cycling constantly: We are enjoying about 100% humidity here.

Greg.
Leaking DNA far and wide

Originally Posted by gregoryq

C-47 rang me after seeing Ken's photos...I wasn't aware that the nozzle stuck so far out of the gun. I just tried it correctly: Yowie that stuff stings!

So yeah, gloves. Two pairs I think.

Greg.
Leaking DNA far and wide

That sounds more like it Greg. I have never held mine to a finger, but I know mine stings more than my 1650psi pressure washer does. When doing small things I can see it blasting away the leather glove.

Hi Ken,
I use the type that has the gun and a rubber hose that goes into the media. You can pick them up at super cheap autos, markets, ebay, etc.
I don't know what size glass I use as I get it off the local sand blaster for free, it is a bit coarser than sand. I used to use sand and it worked fine, but the glass does cut quicker. I find you can get a second cut (by recycling) out of the glass but you see the difference and by the time the 3rd recycle comes around it is almost like dust.
I usually hold it about 1/2 inch to an 1 inch away to get best results.

Dave

C47 must have been on the ball to spot the nozzle being out of position. It's all a learning curve for those without blasting experience.

Greg, might have to return for another go.

Were the second results much different to the first?

Dave, thanks for your tips.

Ken

Originally Posted by neksmerj

Were the second results much different to the first?

Dave, thanks for your tips.

Ken

Couldn't really tell, Ken. The cat wouldn't stay still long enough to tell the difference. Plus it was getting dark. I'll let you know tomorrow.

None of our pets appreciate a good science experiment. I wonder how Edison got his start? ...Sparky! Come here boy!

Assuming the cats have returned, have you had a chance to determine whether the additional efficiency of the gun made any difference to the blasted finish?

Would be nice to get a "silver glittery" finish as described above by Dave.

Ken

Ken, the finish might be a touch more s-g, but its marginal, and in fact I am going to get the plater's opinion tomorrow. I have a new-in-box Deckel wheel for control purposes. I am going to bring it and the tarnished ones to his shop. I am convinced that the surface finish that we are after is only obtainable from satin chroming, and only on a very smooth surface.

After talking with Alan I think the process is going to go via a blasted part which is then sanded with 600 & 1200 grit paper before it goes to the plater. Anything less will be a disappointment, anything unplated will quickly corrode anyway.

Or doesn't in this case because there's a sign on the window, closed. 2008. Otherwise the building is unchanged. A little of that lime-green hexavalent chromium leaking out from under the door. I swear the curtains moved a bit...it could have been the Gimp back there. On the way back to the car I passed a cockroach walking upright, smoking.

So now I have to find a new plater. And a new neighbourhood.

LOL

Dave