Sand blasting nozzles

[dieselsamurai]

Hi just wondering if anyone else uses this type of sandblasting gun ?



pretty sure it came from Machine Mart
I had this one before and the ceramic nozzles last 10X longer



you can buy a set of spare nozzles from MM but only come in pack of 4 and the 7mm too big and the 4.5 never worked for me

So I bouth these from ebay as seemed like a bargain for a tenner


What I failed to check in my haste is the size they are all 4.5mm and I just cant get it to draw sand into the airflow 5mm work fine

is there any way to drill it out larger ? ive tried a tile drill the leaf shaped one and it glows red after hardly making a dent in it do you think a dimond tipped one would work ?

 

[Seadog]

A Dremel with a small diamond tool might work.

 

[frank horton]

it's ceramic....only thing that will touch em is a diamond........

 

[graffian]

Yep I use that sort of gun. Mines a spot blast gun minus the baggy and shroud thingie.
I have no idea what the nozzle looked like but I can get my finger in it now and I think there is even some
light visible from where the bead has tried to make an exit though the top of the gun.
My thoughts are, it should work with big hole, but to small a hole and you won't get enough airflow to suck the **** up?

 

[dieselsamurai]

Change your blasting media? I hope it is not silica sand!

its not the media as works fine with 5mm nozzle just so odd that .5mm less stops it drawing any media at all . ive never used sand !!

 

[graffian]

Stick an old vacuum gauge on the siphon pipe with the different nozzles on
the gun.
I am guessing the small hole is cutting airflow, no airflow no suction.

 

[dieselsamurai]

Yep I use that sort of gun. Mines a spot blast gun minus the baggy and shroud thingie.
I have no idea what the nozzle looked like but I can get my finger in it now and I think there is even some
light visible from where the bead has tried to make an exit though the top of the gun.
My thoughts are, it should work with big hole, but to small a hole and you won't get enough airflow to suck the **** up?

the bigger the hole in the nozzle the less pressure behind the media to do its job . I usually change the nozzle when it gets to about 7-8mm as it stops being effective then

 

[graffian]

My gun has a hole I can stick my finger in.

 

[dieselsamurai]

Stick an old vacuum gauge on the siphon pipe with the different nozzles on
the gun.
I am guessing the small hole is cutting airflow, no airflow no suction.

Yeah your probably right its just wierd that they come with that nozzle in the pack of 4 but its never worked for me and the only large numbers of these nozzles you can get online cheap are the ones that dont work !!

 

[dieselsamurai]

My gun has a hole I can stick my finger in.

are you running big CFM though ? the setup we had at my mates place had a nozzle like that but would blast a hole in 2mm steel if you held it in one place too long ! did run off a 4cylinder diesel powered compressor though mine is only 3hp

 

[8ob]

You may be better off with a gravity fed gun.

Bob

 

[dieselsamurai]

You may be better off with a gravity fed gun.

Bob

Hi it works perfectly with the next size nozzle ive blasted Alloy wheels and multiple things over the past 10 years but its just odd i can only buy 4.5mm nozzles in bulk cheaply
Ive got a pressure pot too and that uses the white type nozzles you can buy them in bulk

this is the cabinet its got fan extraction through an automatic shaking filter on the back , its run off a 3hp compressor in a soundproofed enbclosure in the workshop store

 

[dave h 2]

The paint gun version would choke up, you have to sleeve the pickup tube, your gun may be similar.

 

[Erie Fred]

its not the media as works fine with 5mm nozzle just so odd that .5mm less stops it drawing any media at all . ive never used sand !!

When you used the smaller sand nozzle, did you install a smaller air nozzle as well ?

 

[dieselsamurai]

When you used the smaller sand nozzle, did you install a smaller air nozzle as well ?

I did think that may be an issue but there is only one size of spare air nozzle supplied with the gun and 4 ceramic nozzles 4.5mm 5mm 6mm and 7mm

 

[Agroshield]

The diamond tile drills are very cheap off eBay.

If the size is critical, it would be worth drilling an actual tile first and measuring the hole produced as the diameters written on them are really only nominal.

 

[Erie Fred]

I did think that may be an issue but there is only one size of spare air nozzle supplied with the gun and 4 ceramic nozzles 4.5mm 5mm 6mm and 7mm

Try taking an air nozzle and soldering it up. re-drilling smaller.

There is a ratio of air nozzle area to sand nozzle area. What it is I do not know.

I think too much air is being admitted into the venturi area, and too small of sand nozzle is blocking things up a bit.

 

[graffian]

are you running big CFM though ? the setup we had at my mates place had a nozzle like that but would blast a hole in 2mm steel if you held it in one place too long ! did run off a 4cylinder diesel powered compressor though mine is only 3hp

~15cfm compressor.
No idea what it was like originaly.

 

[dieselsamurai]

Diamond tipped drill. I have done it myself because could only find them cheap in a few sizes and wanted a specific size I was using before. Takes ages. Use water aswell.

Ordered a 5mm diamond drill if it ends up 6mm I know it will work and 20x tips should last ages , once its over 8mm effect starts to degrade

 

[MetalMonkey]

If you can figure out a way to get them to work a bit, even if it isn't on your usual media, they will soon make themselves that 0.5mm larger automatically.