LVLP spray gun and compressor?

[Chris152]

We're looking to get a quiet compressor to spray a car and work air tools. I quite like the look of the Hyundai range ( Buy Air Compressors | Silent Oil-Free | Hyundai Power Products ), but when I look at the CFM/ FAD requirements of LVLP guns, they tend only to publish CFM requirements of the guns, or else the compressors of other makes tend to advertise the CFM but not the FAD. Bit confused tbh.

I understand the FAD is about 1/3 less than the CFM, and that FAD is the figure we need to at least match to the gun.

Can anyone make any recommendations on a decent quiet compressor (60db sounds nice, but I guess 70 would be ok) with good customer support, and maybe a LVLP gun to match?

Thanks, Chris

 

[__jvc26]

I’d recommend giving Mike and the team at Homepage - Sprayman a call. In my experience knowledgeable , great products great service.

 

[Chris152]

I’d recommend giving Mike and the team at Homepage - Sprayman a call. In my experience knowledgeable , great products great service.

Thanks. I just looked at his site - for me it's quite expensive for ones that can operate a spray gun, I'm hoping to pay a few hundred pounds max for the compressor.

 

[AndyMc]

https://www.spraygunsdirect.co.uk/product/a-n-i-r160-q-spray-gun-hps-gravity/
Officially needs only 4.2 CFM but I'd recommend at least a 50l compressor. I have the 24l Hyundai and it's not quite enough to push anything above water consistency.

 

[Chris152]

Thanks Andy - so that gun together with this would work well?
https://hyundaipowerequipment.co.uk...00psi-oil-free-low-noise-electric-2hp-hy27550Will that one work for spraying car panels tho - it says:
'small, lightweight and highly detailed Spraygun that is designed for spraying jobs in the most awkward spots. [...] The smaller nozzles are for small design work and the larger nozzles are for minor spraying.'

 

[AndyMc]

Thanks Andy - so that gun together with this would work well?
https://hyundaipowerequipment.co.uk...00psi-oil-free-low-noise-electric-2hp-hy27550Will that one work for spraying car panels tho - it says:
'small, lightweight and highly detailed Spraygun that is designed for spraying jobs in the most awkward spots. [...] The smaller nozzles are for small design work and the larger nozzles are for minor spraying.'

Can't say I've tried a car panel. I've not used mine much but I did spray some doors with acrylic primer. It was a painful process as the compressor was too small, I needed to pause every 20 seconds to let it repressurise, hence the suggestion to go for a larger unit. However the results were good in the end.
When buying, I found this useful:

 

[Chris152]

That's really helpful Andy - thank you.

 

[undergroundhunter]

I bought the spray gun Keith uses in the above video for a built in project I had going. It's a nice smaller gun, the spray fan is quite a bit smaller then my hvlp guns but it also goes through considerably less air. The finish off it is great. My hvlp guns I need to stop after about 30 secs to let the compressor catch up, with this gun I can just keep spraying with no loss of pressure at the gun. My compressor is a generic 50l nothing special. Luckily for me where I work have a fully kitted out spray booth with a 200l compressor should I need to use it.

Matt

 

[Jameshow]

Could you put it in an acoustic surround?

 

[Chris152]

Thanks both.

Matt - the gun does sound good, but could you set about car panels with it (not the whole car in one go) and expect reasonable results?

James - Not really, we're very pushed for space (my lad's rebuilding an MG Midget in our single garage, which we also have a metal lathe and bench-top milling machine in) - every inch counts!

 

[MikeJhn]

Most all the F1 teams now days use HVLP equipment, recommend Fuji which surprisingly is Canadian, hose length is long enough to put the turbine outside and spray inside.

https://www.axminstertools.com/instantsearch/result/?q=fuji spray

 

[Chris152]

Thanks Mike - though we're looking to get something that'll allow use of air tools (and also can be used for cooling welds on car panels, apparently...) as well as paint spraying. The more I'm reading and watching, the less I know which compressor to go for!

 

[MikeJhn]

I did not think anyone used air tools anymore, modern battery tools are so convenient without air lines, never cooled a MIG or TIG weld on any car panels I have welded the gas from the weld does the cooling, I think you may be a bit behind the times Chris.

 

[Chris152]

You could well be right there, Mike!

 

[Chris152]

Continuing to engage the strange (to me) complexity of air compressors, I notice that the Hyundai 50L machine is just 60dB, but that's at 7m - we can't get 7m from the things in our garage. Is 7m a normal distance to measure noise levels? Is it standard?

Hyundai also have a 100L machine ( Hyundai 100 Litre Air Compressor, 14CFM/116psi, Silenced, V Twin, Direct Drive 3hp | HY30100V ) that runs at 70dB @ 7m - looks great, but very big for us - unless we site it in our utility room which is just a few metres from the garage.
Another thing I've noticed is that, while most people say FAD is about 30% less than stated CFM, Hyundai seem to lop off about half the CFM to give their FAD - the 50L one is CFM of 11, FAD of 5.28; and the 100L is 14CFM, FAD of 7.
But at least they list a FAD - most makers don't seem to, which leaves me wondering if their FADs are more like half the CFM rather than 1/3rd.

Fascinating stuff eh?

 

[Chris152]

I think maybe I'm narrowing things down a little, but here's a quick question on Fad requirement of a HVLP gun:

the compressor I'm thinking of is FAD 5.28;
an example of a lower pressure HVLP air gun requires 4.5 - 6.5 FAD (can't find a link now).

What does that mean for the function of the gun with a compressor with FAD of 5.3 ish? Does it start to splatter with thicker paint?

 

[MikeJhn]

Any HVLP gun run off a compressor is a compromise and will not give the advantages of a real HVLP set up, less overspray, uses less paint and the air is warmed through the turbine and helps the paint to go on smoother and dry's quicker, when I sprayed four 2.5M high doors I could start at one end and immediately put on a second/third coat, I would never go back to compressor spraying again. Can't help repeating the fact of less overspray really is a revelation. Also don't underestimate the value of a non bleed gun, having air constantly going through the gun when not spraying kicks up dust in the workshop with obvious results.

You may find this interesting: HVLP investigation

 

[h-magic]

My two cents if you’re going to re-spray a car get a decent gun then match your gun with the air compressor.
Most guns are 14cfm.

200 Litre minimum air compressor, with 16cfm buy a secondhand clarkes/machine mart or something similar, spray the car with it then sell it and get a small Hyundai to fit in your workshop.

You won’t be able to achieve a decent finish with the Hyundai air compressor without either doing a pannel at a time or using a LVLP gun which has its limits.

This is how it will go…
You will start to spray your primer with a 1.8 gun.
You start of great then half way through the pannel you notice a change of how it sprays. You realise there’s not enough air.
So you wait for the air pressure to build up then start off again.

Then forget you will need decent mask for spraying and avoid using cellulose paint.

 

[Chris152]

OK, a little context might help. My lad's learning classic car restoration, in the early stages but doing a welding and fabrication course. Hence we got a fairly rotten Midget. I think his real interest is in working with the metal, but by getting a car that needs a full rebuild he'll get to try everything and can make decisions from there.

We've talked about it at length and I think his plan would be to get someone else to do paintwork - the kind of kit/ environment you need to get a professional/ top end finish clearly costs a fortune. He should be fine with time to get bodywork through final stages of prep/ primer, but then pay for the finish. But, I'd like him to have a go at final finish, just so he's been through all the stages, and I'd like to have a go at it myself. In the end, the midget will probably be a keeper, something we rebuilt together, so the actual finish isn't crucial - so long as it looks ok from a few metres, it'll be ok (We'll aim for better, of course.)

He's also clear that a compressor will help out in the workshop (apart from air tools, it'll be good for clearing metal chips from the lathe and mill etc).

So, the compressor would be used for general workshop use, application of primer, and (probably just) one bash at applying colour, til we realise we're hopeless at it. I'm not clear what paint to use, still trying to look into that.

Mike - that HVLP system review is great, thanks for the link. I think I understand what you're saying about it being the future now, but at the price for a good one probably doesn't fit the bill - unless he falls in love with painting at some point!

Point taken about cellulose, h-magic - thanks.

 

[Chris152]

Well, we went for the Hyundai Silent 50L compressor that I linked to in the first post - I saw if for £279 at B&Q, which was pretty darn good compared to elsewhere, then they clinched the deal when I noticed they offer 10% discount if you're a B&Q 'member' (which is free), so a total of £247.50 plus £12 delivery. Worth looking at if the machine would suit anyone else's needs.

Thanks for your thoughts all.
C