How big a compressor do I want?

[northwind]

I'm still swithering between using the nitrocellulose Halfords sell (which is easy to get, cheap and not lethal) or go the whole hog and use 2-pack... In either case, can anyone tell me what sort of spec compressor I'm going to want? Will I find it easier to get good results with a higher spec unit?

Likewise, what should I be looking for in a spray gun?

you need a good compressor and a very good spraygun for decent results, a bad sprayjob can be blamed on the tools :P

Im 30 years behind on paint technology, there only used to be cellulose, or coach paint for vehicles, and emusion for houses.

But, the compressor must be cabable of keeping up with the gun.

Do not just look at pressure, the most important thing is volume, measured in CFM, cubic feet per minute.

Look for something that gives at least 10cfm

have a look here:

http://www.autorefinish.com/auto1/Se...pressor%20size

You also need to consider your facilities - 2 pack paint has isocyanates (think cyanide) in it and you must wear full-body protection with an air-fed mask thats kept at higher than atmospheric pressure (unless you want to die)

And you need to control temperature, especially the panels you're spraying.

Is this in the correct forum area? not exactly SV Talk, Tuning & Tweaking

And remember that no amount of equipment can make up for poor prep. You should be spending much more time prepping the job than spraying.

I'd also reccomend getting a regulator to get an even air flow, one with a separator to get the moisture out of the air would be useful.

Also what guns are you going to use. Devilbys (sp?) are the best, but obviously at a price...

Finally, how big is the job you are doing?



This was done using cans and except where I stripped the paint off putting the front dralier on, the didn't get enough of the wax off before touching up the down tube (and got lots of micro bubbles on the down tube - see what I mean about time spent prepping...), it looks fantastic and has lasted two years so (not bad considering cycles are not treated that well when parked in Holland).

Although you can't see in the picture it's Tahiti Blue (blue and purple).

Good luck anyway.

Stu

you wont get any different results with a bigger compressor but it will make its life easier(and longer).you should find out the total c.f.m value of everything the compressor will have to feed(spray gun .mask-if air fed,thats about it) and your compressor ( will have a c.f.m rating) try and get one that has a rating ABOVE your total c.f.m otherwise your compressor will b struggling to keep up.use a good spray gun and empty the compressor of water (there should b a drain valve underneath) most big body shops have filters /water traps to keep it down as water in the paint is a no-no.

[northwind]

Cheers folks. I'm sure I'll be along with more questions shortly...

Can anyone recommend a decent quality budget gun? Going by the info above I should be able to use my brother's compressor, but his gun is a cheapy Clarke one, so I'll definately be looking for a decent gun at a decent price...

I know prep's where most people let themselves down- I've been taking a lot of time over prep work so far, all that remains is to get them as clean as poss before spraying I reckon. This is one reason I'm trying to avoid hiring a compressor- I don't really want to be working to a deadline with this.

Basically don't bother, it takes alot to perfect the mix and application of the paint. You are better off getting cans from someone like RS Paints or Wessex Auto Colours. I have all the kit to spray cellulose & 2-pack and normally resort to cans as it's easier to get the right effect.

Don't forget you need to thin the paint as well as clean the guns after the job. You also need to mix in activators with 2-pack. It can give nice results but it takes a proffesional (or seasoned amateur) to get better results than a can

[northwind]

Really? That'd be ideal, but (no offence) it's a pretty minority opinion. I know you can get as good results with spray cans if you put the work in- I've done it myself- but I'd generally heard it's far harder to get a decent finish. Certainly laquer from a can seems to orange-peel like a mofo whenever I've used it...

The other thing,wouldn't buying by the aerosol work out expensive for a whole bike? I just used most of a 500ml can to spray my mudguard- obviously you get a lot of wastage with smaller parts...

I had a couple of PMs on the subject so here's a wee bit of clarification- I'm not doing it myself to try and save money, Big Al made me a very good offer to do the bike a while back. I'm doing it because it's as much about doing it for me as it is having the job done. I'd sooner have a 9/10 spray job that I'd done myself than a 10/10 job I'd paid for...

Originally Posted by northwind

Really? That'd be ideal, but (no offence) it's a pretty minority opinion. I know you can get as good results with spray cans if you put the work in- I've done it myself- but I'd generally heard it's far harder to get a decent finish. Certainly laquer from a can seems to orange-peel like a mofo whenever I've used it...

To paint the bike yourself your looking at basically 2 compressors, one for the guns and one for the air-fed breathing system. So thats £250+ for the gun compressor, remember to get the right CFM rating and £150+ for the breathing aparutus compressor. Add £200+ for the breathing kit itself, then £25 (ish) for the gun. About £50 for the paint and £10 (ish) for a gallon of thinners (trust me you'll use it).

So thats knocking on the door of £700 for the kit and paint before you even break the gun out of the packaging. Then consider you're environment. Where are you going to be spraying this bike? In a garage? You will need to strip and clean the garage and ensure it's dust free before you start or you'll pick up all manner of bits in the paint.

Do you live on an estate where this kind of activity is allowed? 2 compressors running in the fresh air make alot of noise (they need uncontaminated air) and the fumes from the paint reaks. Doesn't make for happy neighbours.

Once you have all the kit, the garage prepped and you're ready to roll ... Did you buy your paint ready mixed or do you need to self dilute? Do you have an area you can 'practice' on to set-up the guns correctly? Is you air-line filtered for both the guns & the mask?


I know you consider my opinion 'minority' and I don't take offence (I'm a notherner LOL) but I've painted alot of bikes and the 'important' ones I always farm out. Takes so long to set-up and clean/dismantle the gear for a days spraying

Is this the only bike you are spraying? How much body work is there, you riding a nekkid or fully faired?


Oh and on the subject of lacquer, sit it in warm water (not hot) for a few minutes and make sure it's well mixed. Spray it on in stages and flat/wet sand each coat before the next is applied. You should get some nice results




If you are seriously into spraying yourself, phone RS Paints and have them send you some ready mixed paints in Cellulose. Then buy a decent gun and prep you're paint area ready. Then head to your local hire yard and rent a compressor for the day. You will need some form of mask even with cellulose or you'll be blowing <insert paint colour here> bogies out of your nose for weeks

I use one similar to this : http://www.machinemart.co.uk/product...0&r=2153&g=120
and it works a treat

If you like you're results then you can buy all the right gear for the next one, if not you've not wasted a lot of cash and can put it to cans or a proffesional respray



Right I need a cuppa after that epic

[northwind]

Cheers Viney- I was being really careful not to step on your toes there since it's the contradictory opinion I often find most useful Still, I'm a little confused at the amount of contradictory advice there is out there...

I checked out my brother's compressor and it's a wee Clarke Tiger, well down on displacement from the recommended 10cfm unfortunately (7cfm) so it sounds like that's not such a good idea. On the other hand, the HSS Large Cellulose Spray System is a 9cfm compressor

Shouldn't need a pressurised mask for cellulose surely? I can borrow one if need be but the spec sheet only recommends a filter mask and goggles.

Planning to spray in the big shed out the back, after sealing everything with plastic sheeting... Not perfect space-wise but it should be adequate I think.

So, slightly back to the drawing board then Cheers