Compressor set up advice

hanvyj · Nov 1, 2015

Just purchased my first compressor, a Sealey 150 litre (God it's huge... barely fit in the back of the estate) 3hp belt driven from around 2002 I think.

I'm planning on doing a full respray of a classic in cellulose. So I'm keen to take it as much water from the line as possible, the current paint work is blistering like crazy.

My plan is to run some 15mm copper pipe along a few meters and some drop legs then to he regulator and water filter. I thought I'd check the diagram makes sense before buying materials:

Using a 1/2 BSP regulator/air filter:

http://www.amazon.co.uk/gp/product/...ue&ref_=ox_sc_act_title_4&smid=A327GSNL65G6Q2

Also, getting the right connector to start things off would be good. I'm going for a 1/2 BSP system (seems ready available for 15mm copper). The compressor had no regulator attached, just a female quick release attachment (I think).

It measures near 3/4 an inch at the thread, and 8mm internal diameter, and looks like this:

I want a connector that goes to a 1/2 BSP so I assume something like this would work:

http://pages.ebay.com/link/?nav=item.view&id=351224774428&alt=web

It's unclear on the quick connector end, I don't really know if it will fit.

The other thing I could do is replace the female quick connector, but I don't know what thread it is. I don't really need the compressor to connect or disconnect quickly.

Also, the compressor starts up as soon as you switch it on at the plug. I took off the soft start switch (I think that's what it is?) and the switch isn't connected to anything. Is this an easy part to replace? Anyone know a nice name for it I can use when googling?

Looks like there used to be some kind of rod that went from the switch through that hole... I'd guess when it broke someone bypassed it altogether and used the wall plug as an on-switch. I had a quick look at the manual online and the only thing I remember is it said not to do that.

Thanks!

roofman · Nov 1, 2015

you can get 15mm copper to 1/2" bsp fittings mate...got mine from a plumbers merchants

pedrobedro · Nov 1, 2015

It's best to replace it with the same type of pressure cutoff switch as it incorporates the unloader valve which you are bypassing using the wall switch. They are available on eBay or elsewhere and not expensive.

dobbslc · Nov 1, 2015

That's the pressure switch. It's a common failure point on compressors, loads on eBay from about £15. Make sure it has the small pipe attached as that dumps the pressure in the pump cylinder head so it can restart easily.

hanvyj · Nov 1, 2015

roofman said:
you can get 15mm copper to 1/2" bsp fittings mate...got mine from a plumbers merchants

That's the plan for most of it! Just need to get a hose from the compressor to the cheapo plumbing fittings.

pedrobedro said:
It's best to replace it with the same type of pressure cutoff switch as it incorporates the unloader valve which you are bypassing using the wall switch. They are available on eBay or elsewhere and not expensive.

Great, thanks that sounds important. I'm assuming it won't even shut off in this state? Lucky I didn't decide to test it further than "does it turn on"...

optima21 · Nov 1, 2015

I ended up making a dessicant air dryer when I got my new compressor, it doesnt need any additional water traps, its at the bottom of this thread

http://www.mig-welding.co.uk/forum/threads/wolf-3hp-dakota-update.55183/#post-654355

normspanners · Nov 1, 2015

The take off drop leg for the filter should come off upwards with a tee, off the cross pipe then turn though 180 deg then down to the filter the cross pipe should then continue straight then turn down to the drop leg with a drain valve.

hanvyj · Nov 1, 2015

optima21 said:
I ended up making a dessicant air dryer when I got my new compressor, it doesnt need any additional water traps, its at the bottom of this thread

http://www.mig-welding.co.uk/forum/threads/wolf-3hp-dakota-update.55183/#post-654355

That's very interesting, I notice you say the usual filters never drained much water for you. I was wondering how effective the home made desiccant ones have been. Does it work well? Doesn't seem that much more expensive, but I'll have to get a regulator anyway so might get it for it's filtering & regulator capability.

normspanners said:
The take off drop leg for the filter should come off upwards with a tee, off the cross pipe then turn though 180 deg then down to the filter the cross pipe should then continue straight then turn down to the drop leg with a drain valve.

Sorry, I'm not 100% sure what you mean. Is this what you're describing?

optima21 · Nov 1, 2015

hanvyj said:
That's very interesting, I notice you say the usual filters never drained much water for you. I was wondering how effective the home made desiccant ones have been. Does it work well? Doesn't seem that much more expensive, but I'll have to get a regulator anyway so might get it for it's filtering & regulator capability.

seem to work fine for me, I havnt had an issue with water since Ive been using it

normspanners · Nov 1, 2015

hanvyj said:
Sorry, I'm not 100% sure what you mean. Is this what you're describing?

Yes exactly then the water runs down along the bottom of the cross pipe and then continues down the leg then the down pipe with the drain becomes the reservoir for the condensation, the take off leg then draws air from the top of the cross pipe and is less likely to take water with it.

hanvyj · Nov 3, 2015

Thanks for all the help.

Does the pressure switch just unscrew in the standard direction? I managed to get it a quarter turn but it didn't feel like it was getting any looser and I didn't want to go stripping some thread (it wasn't easy to turn it that much).

hanvyj · Nov 3, 2015

Got it off. It's 16.5mm so looks like 3/8 BSP. Can't seem to find any pressure switch in that size, just a few NPT

Edit: will just whack an adapter in there, they're not to expensive.

normspanners · Nov 4, 2015

Sorry I missed the part about the drain in the take off leg for what will travel down there the filter should collect IMO.

jordan1 · Nov 8, 2015

What about plastic plumbers pipe & fittings?.

hanvyj · Nov 10, 2015

jordan1 said:
What about plastic plumbers pipe & fittings?.

I want to condense as much air out as possible, so I want a cold metal really.

captain-destructo · Nov 10, 2015

hanvyj said:
I want to condense as much air out as possible, so I want a cold metal really.

cold!!!
try something like this then http://www.mig-welding.co.uk/forum/threads/diy-air-drying-system.50298/page-2

brightspark · Nov 10, 2015

i just chucked a decent heat exchanger all copper pipes with aluminium cooling fins no one wanted it free

captain-destructo · Nov 10, 2015

brightspark said:
i just chucked a decent heat exchanger all copper pipes with aluminium cooling fins no one wanted it free

i believe thats called sods law

hanvyj · Nov 12, 2015

Miles away though, oh well.

First time soldering. Lot of fun, even if I'm terrible at it! I'm sure it will hold together and the rest of the garage isn't pretty.

captain-destructo · Nov 13, 2015

hanvyj said:
Miles away though, oh well.

First time soldering. Lot of fun, even if I'm terrible at it! I'm sure it will hold together and the rest of the garage isn't pretty.

just a side note when soldering joints always do all sides at the same time
ie if a t joint do all 3 sides one straight after the other

Compressor set up advice

Member

Purveyor of fine English buckets and mops

Man at Matalan

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

all the gear no idea

Member

all the gear no idea

Member

all the gear no idea