Anyone ever drill out their spray gun tip?

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ESP47

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I have a cheap Harbor Freight gun that I'd like to modify to use a 2.0 tip to spray sprayable body fillers. I've read about guys drilling them out and then "lapping" the needle so it seats and seals at the tip. There's a video on youtube of a guy talking about doing it and he goes into detail on drilling it out but then just casually mentions lapping the needle without explaining it at all. I can't seem to find any information online on how to go about doing this. Anyone here ever do anything like this or know how to go about doing it?
 
I see no reason why it will not work fine. Assuming your gun is already probably 1.3 or so, 0.7mm is only about 0.03" more. That being said, it will make a big difference in shooting primer. I use 2.0 or 2.2 depending on the primer. And if it doesn't work, you are only out $0. Will it be hard to find a 2mm drill bit? FWIW, a 5/64 drill bit is almost exactly the same as 2mm.
 
I see no reason why it will not work fine. Assuming your gun is already probably 1.3 or so, 0.7mm is only about 0.03" more. That being said, it will make a big difference in shooting primer. I use 2.0 or 2.2 depending on the primer. And if it doesn't work, you are only out $0. Will it be hard to find a 2mm drill bit? FWIW, a 5/64 drill bit is almost exactly the same as 2mm.

What about the bit about lapping the needle to the nozzle? I assume if you just drill it out, the needle wont seat correctly and it'll puke paint out the tip of the gun when the trigger isn't pressed. I'm just not sure how to go about that part of it all.
 
Most tips are tapered. I Use a Divilbis Finishline FLG4 for priming. I can tell you that the same needle in that gun will work for the 1.3 through 2.2 tips. I have used it for paint and clear coat a few times. The spring should push it forward enough IF the tip is tapered enough.
 
Sprayable body filler ? is it a high solid polyester primer or something else.
 
Most tips are tapered. I Use a Divilbis Finishline FLG4 for priming. I can tell you that the same needle in that gun will work for the 1.3 through 2.2 tips. I have used it for paint and clear coat a few times. The spring should push it forward enough IF the tip is tapered enough.

Thanks that what I was thinking but I wasn't sure if there might be something else to it. I'll give it a shot. It's not like the HF guns are expensive anyway.

Sprayable body filler ? is it a high solid polyester primer or something else.

Yeah I was thinking Evercoat's Feather Fill or Slick Sand.
 
Yeah I was thinking Evercoat's Feather Fill or Slick Sand.
I know there are a LOT of high build primers out there but I have always had such GOOD luck with Evercoat primers, that is all I will use.
 
I know there are a LOT of high build primers out there but I have always had such GOOD luck with Evercoat primers, that is all I will use.

Have you used either of the products I've mentioned? It'll be my first time. They seem like they're easier to use for beginners rather than lathering up panels full of body filler and hacking away.

One of the reasons why I wanted to use a product like Feather Fill is because it's just one more step where I can avoid spraying isocyanates. I'd rather not have to spray them until I absolutely have to.
 
Have you used either of the products I've mentioned? It'll be my first time. They seem like they're easier to use for beginners rather than lathering up panels full of body filler and hacking away.
I used to live in Ranch Cordova when I was stationed at Mather AFB. They both work fine, but I prefer the Evercoat G2. it sprays on and sands off BEAUTIFULLY. I use a 2.2, but a 2.0 would work. If the body work is good, you'll be amazed at how good it looks after block sanding.

However do not think that a heavy polyester primer will replace good body work. A paint job will never look better than the surface prep. You still need to use body filler (use Evercoat Rage Gold; it sands a ZILLION times better than BONDO) and LOTS of elbow grease. Electric or air sanders are fine, but the Dura Block sanding blocks I mention below with 80 grit will work fine. Just don't "lather" too much filler on at a time. The more you put on, the more you have to sand off. Thinner layers are best. You should also consider a Glazing Putty (Evercoat of course). It will fill pin holes and minor imperfections very well. It is thinner than body filler and sands easily. I usually block it with 180 and then 220. No way to get a good paint job without buying some materials

You REALLY should buy a set of sanding blocks; Dura Blocks are about the best, and they are quite cheap. Then buy 80, 180, 220, 320 and 400 grit sandpaper in the 2.5" rolls. Get the peel off adhesive back kind. I buy the brand that Eastwood sells. The Brand name is something like Rhyno. I honestly think it works better than the much more expensive 3M Gold. Then apply a light film of guide coat over the cured Polyester (this is a MUST) and start with the 220 grit in a cross hatch pattern. Be careful on edges. The guide coat will make low spots stick out like a sore thumb. Anyway, block with 220 until all the orange peal is gone. Then switch to 320, and use it until the 220 sanding scratches are gone (won't take nearly as long as the 220). Then smooth it out with 400. Then I use 320 wet followed by 400 wet. When the surface is wet you can really see how the paint will look. Good Luck. Feel free to send me a PM if you have any questions.
 
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