Think I've (probably) got a blaster...

[julianf]

Don't know what size it is. It's clearly one of those cheap from China things though.

I know there are a million threads a out them but you can never find the detail when you want it.

I need one of those centuarywise valves, right, and then what is it that I need for the valve end?

Anything else? I have a metalworks water trap but it's part of my regulator, and the regulator will be restrictive, won't it? So do I need some sort of separate water trap also?

I have a couple of aprox 14cfm compressors and one smaller one.


I've not picked up the job yet, and it's never done till it's in your hands, but here's hoping at the £25 asking price...

 

[brightspark]

if you fit the centurywise metering valve cut that tap of the end of the blast hose and fit a 3mm carbide one and fit a half inch bsp machine mart or similar water seperator on the pot and it will work very well .use 10mm bore flexible pipe to feed the pot and away you go I take the air strait from the tank so its not restricted

 

[julianf]

Thank you. Will do as you say.

 

[KavindaJD]

Hi there!
I'm new to the forums and looking to get into sand blasting as well.
How large is your tank for the 14cfm compressor? I'm thinking of just having one 15cmf ~ compressor with a pressure pot - do you think this would be adequate?

 

[julianf]

Brightspark knows better than me, but the size of the tank is kind of irrelevant for somthing where you are running all the time.

They're good for stop start jobs, but it's CFM total that matters for most tasks, not what size tank is present.

 

[brightspark]

2x 14cfm comps coupled together will or should run the pot at 90psi pressure without dropping .its preferable keeping the pressure constant because if it drops you end up using more media with less air and not as much cutting power

 

[KavindaJD]

So a single compressor rated at 14cfm would struggle?

 

[brightspark]

So a single compressor rated at 14cfm would struggle?

it would run a pot but would start to drop in pressure in use . if anyone wants to know what pressure the comp can run a blaster at is get some 10mm round rod and drill a 3mm hole through it insert in to your flexible hose using a jubilee clip and run the comp . then check the pressure while running that will give you an idea of what you will get without forking out on the gear 1st

 

[Dcal]

@julianf Have a look at the nozzle on the blast hose, it might already be a carbide one.
My pot had that same set up and it worked fine until the ball valve disintegrated and I didn't bother replacing it.

I made a metering valve (as has @brightspark ) and they transform the operation of the pot.

 

[julianf]

I picked up the unit today, however it's currently still in the car.

Two things -

It has a water trap on it, so I assume I'm sorted there.

And

The tip of the hose has a white ceramic nozzle. Is this the carbide unit mentioned above? What else are they ever made of?


I'll take some photos in the morning...

 

[Dcal]

The ceramic ones are carp.
this is the one I got, looks expensive compared to the throw away ones but well worth it.

https://www.ebay.co.uk/i/3238566901...MI56S917Lq5AIVTbDtCh3DnQfxEAQYASABEgJtV_D_BwE

 

[brightspark]

The ceramic ones are carp.
this is the one I got, looks expensive compared to the throw away ones but well worth it.

https://www.ebay.co.uk/i/3238566901...MI56S917Lq5AIVTbDtCh3DnQfxEAQYASABEgJtV_D_BwE

there the ones I use on my smaller pot just stuff the jet in to the blast hose and fasten with a jubily clip

 

[eddie49]

For a cheap "ceramic" nozzle, don't forget the old spark plug trick:

https://www.mig-welding.co.uk/forum/threads/sandblasting-nozzle-using-spark-plugs.72297/

 

[julianf]

So, the valves -

There's this one -

https://www.centurywise.co.uk/shot-...metering-valves-/Flat-sand-exp-abrasive-valve

And this one -

https://www.centurywise.co.uk/shot-...metering-valves-/junior-flat-sand-valve-miser


The second looks like what I was expecting. Seems that the first is a fancier version of the same?

By the time I'm spending all that money, a tenner extra is neither here nor there, so, if they both cost exactly the same, which one should I go for?


In other news -

Dragged the unit from the car this evening.

Gassed it up and flicked the valve for just long enough to realise it was a bad idea opperating it where I was!

I reckon I had it open for between 2 and 3 seconds - maybe even less. Long enough to remove a 8-10mm disc of rust impressively cleanly, but also to mist everything in the vacinity with grit!

I had one of those Venturi ones and never saw any good action from it at all. This one seems (from my vast experience of all of seconds!) as if it will be a lot more useful.

I am, however, going to need some sort of enclosure, I think.

 

[brightspark]

the ones I made were copied of the Clemco mini pot and are the same as the junior valve in picture. they work very well with no problems on sand or grit. its not very often they need taking apart for cleaning out if you use new media or sieve it after use .and its reasonably dry