water trap for road compressor - media blasting

[davegeezzer]

Evening gents, been outside all day playing with my sand blaster, Im blasting the underside of my campervan shell that ive rolled over on its side, I built a blast pot from a propane bottle and ive got a clemco 6mm nozzle/ blast hose and the compressor is a road compressor that ive borrowed from my mate, all was going well untill the media (small crushed glass) started clogging in the outlet of the pot. I dont have a water trap on it ! obviously this is my problem but can i use one of my water traps from my normal compressor setup or is something larger needed for 100cfm +?, the plumbing on the pot is 3/4" iron and im sure the outlets/inlets on the traps are 1/2".
Out of desperasion i joined another air feed hose that i left coiled up and submerged it in water to try and cool the air but now thinking about it the air already had the water in it when it was compressed so i think i should get the muppet award !!

 

[brightspark]

all i ever did was when running the blast pot was leave the seperator slightly open run the compressor with air supply open till water was coming out and the air gets warm and the pot pipes warm up and theres never a problem u have no chance of cooling that amount of air .then the comp will run all day long without any condensed moisture

 

[davegeezzer]

cheers Brightspark !!, now thinking what youve said if i remember correctly when i was a young man labouring on a building site they always used to run the compressor to stop the jack hammers freezing up !!

 

[brightspark]

just run it full blast till it all gets hot and warm air comes out then introduce the media . u can put a half inch water trap on the pot. i have one on mine

 

[awemawson]

My 'three drill' 160 cfm road compressor has two water separators that I always leave with the drains 'just cracked open' and I do the same with the separator on my Hodge Clemco blast pot. Even so I used to occasionaly get grit hang ups on moist days until I changed to using crushed glass.

 

[davegeezzer]

all i ever did was when running the blast pot was leave the seperator slightly open run the compressor with air supply open till water was coming out and the air gets warm and the pot pipes warm up and theres never a problem u have no chance of cooling that amount of air .then the comp will run all day long without any condensed moisture

.
Excellent cheers for that ill borrow one from my spray compressor and have another go when its all warmed up

 

[davegeezzer]

I must admit i didnt think it would clog as it glass ! if it was sand i could understand it, but saying that it was raining today and i was sweeping the media up sieving it and re-using it so maybe it picked up moisture going from hot pot to cool damp gazebo lol

 

[stormin]

Ive got a similar set-up to the above. 130 cfm rosd compressor and using 3/4 hose to pot and 3/4 iron piping on the pot. My seperator is only 1/2" bore too. Still get good results once compressor is warmed up. I have wondered whether the trap is restricting the flow slightly and considered upgrading to a 3/4 or inch trap.

 

[brightspark]

clemco use a half inch seperator on there mini pots. 90cfm with a 6mm jet any larger and u may need a 3/4 one your best checking the clemco site for size

 

[davegeezzer]

Hi Stormin out of interest does the water trap collect much water when its all warmed up ?, I decieded against robbing a trap from my other setup today as ive only got to replace it, so i was going to try just warming it all up first.

 

[brightspark]

it wont collect any water when its hot . warm moist air will pass through

 

[davegeezzer]

I definetly wont be buying a new one then to install then !!

 

[davegeezzer]

finally got a break in the rain this afternoon so let the compressor warm up with both valves cracked open then connected the pot with no media in but all valves open then when it was all nice and warm i loaded up with glass media and it was blasting like a good un !!, no blocks all afternoon, cheers Brightspark !!.
Also came up with a good idea i had an old tent given to me, so i used one of the inner tent bedrooms, hung up in the gazebo as my blasting room !! kept all the media nicely contained, it even has a fabric mesh door to let air in/out .