Author Topic: Spray gun advice  (Read 5177 times)

Offline Filmcamera

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Spray gun advice
« on: September 03, 2018, 08:11:25 PM »
I recently got myself a second hand air compressor.  It is a 25 gallon model on wheels that charges to 155 psi.  I am thinking about getting a spray gun to tackle some repainting that needs doing and am looking for advice. So far all I know for sure is that I want a gravity fed model but do not know whether it is better to go LVLP or HVLP. I know I am not going to get a $25 dollar gun nor and I going to get a $500 gun but was thinking somewhere between $100 to $200, preferably with changeable needles (1.8 and 1.5 for example)


I have seen some great paint jobs done by guys on here and was hoping someone could give me a couple of recommendations.
  • San Jose, Costa Rica
  • 1991 K100RS 16v ABS1, 2022 Triumph Tiger 900 Rally Pro
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Offline RobP

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Re: Spray gun advice
« Reply #1 on: September 03, 2018, 10:45:18 PM »
I used a DeVilbiss Finishmaster HVLP gun to paint my K100RS a couple years ago and was happy with the results.  IIRC it cost about $200 or so.   You may want to consider picking up a water separator as well.

A good paint job is 95% dependent on good prep work - sanding primer, making sure everything is clean and so on.
  • Driftwood, TX
  • 1985 K100RS

Offline Laitch

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Re: Spray gun advice
« Reply #2 on: September 04, 2018, 01:41:22 AM »
A good paint job is 95% dependent on good prep work - sanding primer, making sure everything is clean and so on.
Dazzling!  :clap:
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Offline Filmcamera

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Re: Spray gun advice
« Reply #3 on: September 04, 2018, 07:31:27 AM »
Thanks, I had looked at a similar gun already, can I ask what size of compressor you use? I know the parts on bikes are pretty small so it is not essential to be able to spray continuously but even so I was concerned that my compressor might be too small for that gun.  Thanks for the tip about prep work, I will do the best I can to make the surfaces as perfect as possible before spraying anything.
  • San Jose, Costa Rica
  • 1991 K100RS 16v ABS1, 2022 Triumph Tiger 900 Rally Pro
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Offline RobP

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Re: Spray gun advice
« Reply #4 on: September 04, 2018, 09:51:10 AM »
I have a 2-cylinder, 70-gallon upright compressor.  Probably overkill for painting bike components.  Previous compressor was a 5-horse, 25 gallon Craftsman - which would be more than adequate with an HVLP gun.

On a side note:  a water separator works best if it is not filtering hot compressor air.  I routed an extra 50' section of air line between the compressor and water separator (fastened to a hook on the wall in large loops) as a poor man's heat exchanger.
  • Driftwood, TX
  • 1985 K100RS

Offline The Mighty Gryphon

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Re: Spray gun advice
« Reply #5 on: September 04, 2018, 02:11:21 PM »
I have a pair of Harbor Freight HVLP guns that were reworked to clean out the silicone seal they were assembled with and sealed to prevent leaks that drip paint on the object being painted.  Both give excellent results for both base and clear.

Having said that, when I have done any Motobrick painting in the past 4 years I always reach for my $15 Badger model 250 airbrush to do base coat and rattle cans for clear.  Most recently I did the two color tri-coat  paint job on Moby Brick Too with them and it came out very good.  I run it off an old 10 gallon 3HP Sears Craftsman compressor.

The air brush puts down the base slowly enough that it's impossible to get runs or sags, and most important to me, it makes almost no significant overspray so the paint goes a LOT further.  This is important to me when paint can cost 80 bucks a pint.  The airbrush also gives excellent control when I need to do a small repair and only takes two or three minutes and a half ounce of solvent to clean.

I have found that professional rattle can clear coat has gotten a lot better the past couple years.  The nozzles give atomization and pattern equal to good quality guns and don't need any cleanup when I am done.  Perfect for someone as lazy as I am.  I used the new 2K clear on Moby Too and it's even nicer than the 1K I had been using,  By keeping it in the refrigerator between shooting sessions I can get a pot life of up to four days.  The rattle cans waste a bit more product than the air brush, but nowhere near what a gun blows away in overspray.

As mentioned above, prep is 95% of the job.  With good prep I can get excellent results with the cheap equipment I use. 
  • In my garage in Marilla, NY
  • '91K100RS White/Blue
Current:
'91 K100RS16V "Moby Brick Too"

Past:
'94 K75RT "Ilsa, She Wolf of the SS"
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline johnny

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Re: Spray gun advice
« Reply #6 on: September 04, 2018, 02:31:38 PM »
greetings...

one my favorite spray guns...



j o
  • :johnny i parks my 96 eleven hundert rs motobrick in dodge county cheezconsin  :johnny

Offline Filmcamera

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  • San Jose, Costa Rica
  • 1991 K100RS 16v ABS1, 2022 Triumph Tiger 900 Rally Pro
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Offline RobP

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Re: Spray gun advice
« Reply #8 on: September 06, 2018, 01:45:34 PM »
So, Filmcamera . . . .

Did you pull the trigger on a HVLP gun or did you go with Johnny's Kel-Tec?
  • Driftwood, TX
  • 1985 K100RS

Offline Filmcamera

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Re: Spray gun advice
« Reply #9 on: September 06, 2018, 01:48:24 PM »
Still trying to decide to be honest  :johnny  I know which one looks for fun.


I am going to try and do some experiments to work out the effective cfm of my compressor - from there I will decide between the HVLP and the LVLP.
  • San Jose, Costa Rica
  • 1991 K100RS 16v ABS1, 2022 Triumph Tiger 900 Rally Pro
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Offline earlguy

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Re: Spray gun advice
« Reply #10 on: September 07, 2018, 04:05:59 PM »
Mighty Gryphon: I really appreciate the air brush suggestion! What sort of pressure control valve do you use?
  • North Woodstock, NH
  • 1990 K75S

Offline The Mighty Gryphon

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Re: Spray gun advice
« Reply #11 on: September 07, 2018, 08:43:52 PM »
I just set the regulator on the compressor to get 15-20 psi at the regulator when the button on the air brush is pushed.  If I go any lower, the spring loaded water drain on the separator opens up and bleeds off all the air.
  • In my garage in Marilla, NY
  • '91K100RS White/Blue
Current:
'91 K100RS16V "Moby Brick Too"

Past:
'94 K75RT "Ilsa, She Wolf of the SS"
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline Scott

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  • Posts: 77
Re: Spray gun advice
« Reply #12 on: September 07, 2018, 09:49:22 PM »
I use a old school DeVillbis jga-502, hi volume, hi pressure.  Not very efficient,  but at around 60 psi it really lays out a nice pattern.  I usually use a catalyzed urethane enamel with a hardner added.  Just a back yard painter, but I do okay.  I always have a "cheater valve" in line at the gun so i can adjust the air pressure right before the gun.  The pressure at the tip is important for proper atomization of the product for a smooth,  glossy finish.  A pic of my sr500 i painted a couple of years back.  Cheers.

* SR500_210.jpg (80.15 kB . 768x432 - viewed 395 times)
* Sr siderite.jpg (55.66 kB . 768x432 - viewed 400 times)
* Rear emblem-001.jpg (44.17 kB . 768x432 - viewed 379 times)
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