Harley Benton Jazz Bass kit build

[McCreed]

Dood, unless you have noise issues or your compressor is about to cark it, there is no point in changing your current rig. The larger compressor will run at a lower duty cycle and last longer.. save the money and use it to finish your guitars .

Thanks Rabbit. My compressor is still very new in the scheme of things (2 and a bit years). It certainly hasn't been used everyday in that time either. The air gun gets more use the spray gun! Noise is not an issue for me. I only work during the daytime and it's reasonably quiet for its size, and we've got pretty good neighbours.

After your advice, I'm off the idea at this point, but I had a quick look around anyway and it doesn't appear Hyundai are available in AUS. I found one from Sydney Tools that is the same specs as Simon's (24L, 1 HP, 100 psi) but know nothing about the brand (Lincoln?). I thought it was pretty inexpensive though ($179). What brand is yours?

[Rabbit]

Thanks Rabbit. My compressor is still very new in the scheme of things (2 and a bit years). It certainly hasn't been used everyday in that time either. The air gun gets more use the spray gun! Noise is not an issue for me. I only work during the daytime and it's reasonably quiet for its size, and we've got pretty good neighbours.

After your advice, I'm off the idea at this point, but I had a quick look around anyway and it doesn't appear Hyundai are available in AUS. I found one from Sydney Tools that is the same specs as Simon's (24L, 1 HP, 100 psi) but know nothing about the brand (Lincoln?). I thought it was pretty inexpensive though ($179). What brand is yours?

It's an Xcort. I thought it was 24l but it's 30l, 0.75hp/4.2cfm The psi rating isn't realy a thing to pay much attention to, the volume of air it can deliver when the tank has run out and the air flow is primarily from the pump. So long as that is higher than the amount of air your gun uses it's all good.

[Simon Barden]

It's not quite that simple, as the motor will burn out if it needs to run constantly. If the compressor is sized against the airflow of the gun correctly, the tank shouldn't run out and the compressor should at most, run 50% of the time and be off 50% of the time. I have no idea what the maximum run period of the motor should be before it needs to turn off to cool down; that will change from motor to motor. But if the motor starts running and isn't cutting out after five minutes or so (and you can see from the gauge on the compressor if it's pushing the tank pressure up or not), then you are probably using more air than the compressor is designed to provide.

The higher the psi setting on the regulator nearest the gun, the more air you are getting through when you use the gun. So if the compressor is running constantly, try dropping the air pressure setting a bit (if it doesn't affect the spraying). You're getting through double the cfm at 60psi compared to 30 psi, or 50 psi compared to 25psi.

The good thing is that spraying a guitar body doesn't take long, so you are unlikely to damage the compressor motor with a 5 minute spray, even if the motor is running all the time. But if you use the compressor for spraying anything larger so it need to run for longer, or use it for air tools that use a lot of air and you are doing say a big sanding job, then keep an eye on the motor run time and take breaks to give the motor a rest if it looks like it's running for too long.

[Simon Barden]

Lightly sanded down today without any sand-throughs. A bit cooler than expected, so waiting to see what tomorrow brings before spraying some protective clear coats.

[McCreed]

The psi rating isn't realy a thing to pay much attention to...

Yeah, that a bad cut & paste by me. Meant to include LPM, free air delivery. Thanks again.

@ Simon - Yay! no sand-throughs!!! (I hate it when those happen)

[Simon Barden]

I'm not sure that deciding to clear coat over the blue was such a good idea. I have no idea where it came from, and I was using my 'clear only' spray gun, but a few seconds after I started spraying the clear, a streak of dark brown got spat out from the gun. A flake of something must have fallen in the container in the box I keep them in. Which was very annoying. So I stopped, , tried to wipe it off (stupid), which only mixed it up with the blue on the body. So I left it for an hour and sanded back and it looked OK (if not 100% perfect).

But in sanding I had left a dark mark on another bit of the body, so when I came to spray the clear again, I realised I was coating over this mark. So I left it, tried sanding back, but it left a spot of a very slightly different colour. I had a tiny bit of blue left in my mixing jar, so brushed that on. But that didn't help as all the lighter, whiter, pigment in the paint had settled to the bottom, despite being shaken, and the blue was now lighter and very obvious.

So I managed to thin down the paint that remained in the bottom of original tin and add that to what was left in the mixing jar, and had just enough to spray a complete covering coat of this slightly lighter blue over the body and cover up my mistakes (it ran out as I was doing a final pass for luck). In fact, I've now ended up with just the tint of Sonic Blue I was after. But there's not enough thickness to sand again, but as the finish was flat before spraying, it's good enough to clear coat straight over. So I'll do that tomorrow after a thorough clean of the gun.

[McCreed]

Bummer about the "brown streak" (that's usually an entirely different topic ).

I appreciate your sharing when things don't necessarily go to plan or a mistake is made. It just shows that no matter how long we may have been doing this or how much experience we have, the "stuff happens" principle applies to all of us!

Tomorrow's another day! Hopefully the next round of clear goes well.

[andybanks]

There's an old story that goes around for pilots that says "when something goes wrong, the first thing you should do is check your watch". It is apparently meant to encourage a pilot to take a moment to think before they act.

Of course, I still do the same thing and often end up wiping or touching a run or an imperfection even though I know I shouldn't. Maybe I should wear a watch? That would be a novel idea.

After seeing some of your other builds I nature you'll nail this one as well. Looking forward to seeing it.

[Dikkybee007]

After many years of spray painting experience I have now put in place some precautions that remove most problems in cleanliness of equipment. In the past I have had problems with gun and line due to exterior contaminants. After my last problem I now have a procedure that I follow religiously. I always clean the gun and store in a plastic zip bag which I put into a sealed plastic bucket for ease of storage and clean before I use said gun and check for any defects. I use rubber plugs that seal my line as I had a bug get in either my gun or line and blocked the spray gun and I store my line in a sealed plastic bucket just to keep everything clean as I don't want to contaminate my surface with dirt/dust falling off my line. It maybe excessive but since following this ritual I have had no problems that needed the surface to be sanded back and started again. If you are going to put so much effort into using a spray booth then spending a little bit more time in all aspects of your equipment and environment will pay off in the long run. Try also locating the compressor in an area where it doesn't need to be moved to enable you to use it as it will reduce introducing leaks. I have my unit under a table and a line runs to a place near where I use it so I never have to set it up each time I use it but mine is probably 5 times what I need but I got mine for about $100 as I made it from parts I either was given or bought.

In industry air compressors should cycle no more than 4 times an hour so it will be only running for about 7-8 minutes and idle for about the same time but that is for 9 to 13 hour run times. I have maintained units that ran 24/7 as they were so larger it would take almost an hour to fill the tank from empty. To help with cycle times always make sure all lines and compressor connections are free of leaks and are kept as short as possible. If used in short stints of less than an hour once or twice a week products of the day are quite capable of these running conditions even if the compressor is running continuously though not ideal as your flow may not be consistent. I have worked on motors that run 24/7 for 3 years and only needed bearings replaced and were good to go again. Always drain your tank and water filter after each use as there will be time, like during winter, when the unit wont be used for an extended time and if there is water sitting for that long then it could damage the unit.

If cycle times are too high then you will need a bigger unit plain and simple as its capacity is not adequate or the unit is faulty. You could change some pressures but that will only get you so far and unless you have the skills to replace the compressor or tank then a new unit is in your future. I would always buy maybe 50-100%, aiming for closer to 100%, larger than needed as I want due to your circumstances may change in the future. Budget is always a sticking point but so is buying the wrong size to begin with. Replacing the spray gun with a unit that requires lower compressor capabilities could also be an alternative. Once you buy the compressor you can check it by hooking up the gun and spraying air to simulate your conditions and maybe try some changes in pressures or even gun technique. Even if it cycles every 2-4 minutes for an hour, in short spray times it should be fine.

[Simon Barden]

Yes, I certainly need to up my game at keeping things clean, and you've got some good tips there Dickybee.

So; on to how my clear spraying went today.

Don't ask. Another bottle of Sonic Blue is on its way to me. 'nuff said.