Needle gun for rust removal

[Simi 60]

Bound to be a few steel boat owners here that use them onboard.

I want one as we have a few steel items onboard that need a clean-up and paint with kill rust epoxy enamel, engine mounts, steering quadrant to name two, both are impractical to remove and are heavy built items.

Reading up says that you need a large compressor but I am thinking that's if using one full time

The needle scaler allows you to restore metal surfaces to shiny smoothness in seconds, and it only requires 8 to 16 cfm at 90 psi.

Living on a boat we have one of these for hookah, would it be capable of running a needle gun for short bursts?
it has a 67 litre/minute airflow which is 2.3cfm

Ozito 24L 1.5HP Oil Free Air Compressor


https://www.bunnings.com.au/ozito-24...essor_p6290553

[Sailmonkey]

It’ll run a needle gun for an obnoxiously short time, the compressor will run continuously and likely trip a thermal breaker.

Without proper air you’re better off with a grinder and a wire wheel or an electric needle gun if you can find one to rent

[GordMay]

Here’s 3 examples from Grainger Canada (all 3 require 90 PSA pressure)

Average CFM @ 15 Second Run Time 1.10, CFM @ Full Load 4.5
➥ https://www.grainger.ca/en/product/N...ytics=required

Average CFM @ 15 Second Run Time 1.2, CFM @ Full Load 4.6
➥ https://www.grainger.ca/en/product/N...ER/p/CNPCP7125
or
Average CFM @ 15 Second Run Time 3.00, CFM @ Full Load 5.5
➥ https://www.grainger.ca/en/product/A...ernateProducts

8 Bar pressure = 116 PSI - so OK there.
IMO, At 2.3, you look a little light on CFM, though.

[hpeer]

As a steel boat owner I will offer you an alternative.

I use an oscillating tool with an old saw blade. Instead of trying to saw with it turn it sideways and let the blade vibrate against the intended object.

I call it my “One Needle Needle Gun”. I crack me up.

Its not as good as a needle gun for heavily rusted areas. On the other hand it beats the dickens out of other options. No compressor needed.

You can work it into some pretty tight spaces and use the blade tip to work into pits and such. If you turn it more sideways it works pretty hood for removing paint.

On heavy rust it takes some patience but generally if it wont work then you have a bigger problem.

Is this how a oscillating tool was intended to be used? Hell no!!! Does it work? Hell yes!!!

Give it a try. You will wreck a blade or 3 in the process. Occasionally they break off. But its cheaper than a compressor and needle gun.

I have also used a 6” piece of wire role chucked up into a drill or even a chisel crammed into a drain snake on one occasion. Whatever works.

[Rennsail]

I've done a few extensive car restorations. Mostly older air-cooled Porsches. If they have been neglected, they will have plenty of rust. I have a needle gun and I rarely use it. It is useful for very tight/obstructed spaces, outside of that, they are fairly inefficient. Your best bet for typical rust removal is an angle grinder with a twisted steel wire wheel. It has to be twisted. Don't get a straight wire wheel for steel or iron. Get the twisted one. Like this.

[hpeer]

If you are going to use a grinder use a flap disk.

I also have a ZIP tool, it takes a 1/4” shaft and will spin small grinding stones well. Its just a fancy multi-speed die grinder at that point.

[AKA-None]

Well do you want to reduce metal or knock off rust? Grinding or sanding reduces metal and won’t get in tight places. If you want to knock off rust use hperr idea. It’ll bounce a lot but won’t reduce metal.
I’d go air tool if I had a lot to do, my preference.
If you have a steel boat then invest in an air tool and do it right as you will be using it a lot.

[ShoreFun]

No it will not be worth your while. You would be better off renting a gas powered compressor. But really you are not likely to do much good with a needle scaler. I have used them and not for rust removal. I do car restoration. I know rust. I have sandblasted 3 full cars. I have a glass bead cabinet. I have used electrolytic rust removal. I have tried acid based rust removal.

If you can not get 100% of the rust off then you are not doing it right. Just paint it with stuff that will slow down the rusting.

Case in point.

I blasted down some window channels for a 31 Model A Ford Cabriolet. I was not going to be able to deal with the repair work for a while so I used a light acid and polymer rust preventative. The name slips my mind. I did get all the brown out of the bottom of the pits. A few months later the rust in the pits were able to blossom out. Keep in mind the rust has excess oxygen so even if fully sealed from air by a coating the rust will still continue working if you do not make it fully bare metal and treat it effectively.

There are coatings like POR-15 that supposedly bond to the rust and prevent air from getting in. They are usually coatings that are not well bonded to the base metal and can come off like a mold of the part.

Anyway some thoughts and experience from my past. It is not easy to do proper rust work. You usually have to make compromises. Educate yourself and make informed choices.

I recommend that any salt water base rust you consider if you can do electrolytic rust removal. That will also remove the salt in the metal. Look it up. That is how they preserve historical items that are rusty.

[AKA-None]

Well you’ve done cars and I’ve done ships so unless you’re sandblasting I’d go with a needle gun
Ymmv

[Simi 60]

Thanks for the replies
I'm not going to get into places with a wire wheel or sanding discs
The multi tool with blade is certainly an option if the needle gun definitely won't work
And being a timber vessel a multi tool will have additional uses that the needle gun won't.

Saying that, I reckon the needle gun will make short work of the job in not so comfortable positions

[Simi 60]

Originally Posted by GordMay

Here’s 3 examples from Grainger Canada (all 3 require 90 PSA pressure)

Average CFM @ 15 Second Run Time 1.10, CFM @ Full Load 4.5
➥ https://www.grainger.ca/en/product/N...ytics=required

Average CFM @ 15 Second Run Time 1.2, CFM @ Full Load 4.6
➥ https://www.grainger.ca/en/product/N...ER/p/CNPCP7125
or
Average CFM @ 15 Second Run Time 3.00, CFM @ Full Load 5.5
➥ https://www.grainger.ca/en/product/A...ernateProducts

8 Bar pressure = 116 PSI - so OK there.
IMO, At 2.3, you look a little light on CFM, though.

Thanks for that info

15 seconds at a time I can live with and yes, definitely light on cfm wise.
Rather unfortunate

[NSboatman]

Originally Posted by hpeer

As a steel boat owner I will offer you an alternative.

I use an oscillating tool with an old saw blade. Instead of trying to saw with it turn it sideways and let the blade vibrate against the intended object.

I call it my “One Needle Needle Gun”. I crack me up.

Its not as good as a needle gun for heavily rusted areas. On the other hand it beats the dickens out of other options. No compressor needed.

You can work it into some pretty tight spaces and use the blade tip to work into pits and such. If you turn it more sideways it works pretty hood for removing paint.

On heavy rust it takes some patience but generally if it wont work then you have a bigger problem.

Is this how a oscillating tool was intended to be used? Hell no!!! Does it work? Hell yes!!!

Give it a try. You will wreck a blade or 3 in the process. Occasionally they break off. But its cheaper than a compressor and needle gun.

I have also used a 6” piece of wire role chucked up into a drill or even a chisel crammed into a drain snake on one occasion. Whatever works.

Hpeer speaketh the truth!! I do exactly the same thing- and it works damn well.

The other thing I have that is indispensable is a Milwaukee band file. Like a skinny belt sander with the belt sticking out like a wand. It’s only 1/2” wide so you can brandish it like a sword and really dig down into pits and crevices. It’s incredible at preparing complex surfaces. Belts available all over, but I get mine off McMaster carr- you can get belts designed for metal removal in 40 grit that will chew thru metal like you wouldn’t believe.

These two, plus a grinder with a 40 grit flap wheel for larger flat areas, and a second grinder with a stainless steel stringer bead wheel for polishing, and you can prepare anything for paint.

... and yes, my name is Ben, and I have a problem... I own a steel boat.

[Simi 60]

This be the device me thinks
Runs on the same 18v batteries that my new ozito drill has

https://www.bunnings.com.au/ozito-px...-only_p0098552

[Bunji]

Originally Posted by Simi 60

This be the device me thinks
Runs on the same 18v batteries that my new ozito drill has

https://www.bunnings.com.au/ozito-px...-only_p0098552

Funny that was just thinking the same thing, I have the ryobi multi tool, have also used hammer drill with modified chisel bit for those hard to get at places. (Boilermaker/welder) killrust enamel is ok, por 15 Is better

[Simi 60]

Originally Posted by Bunji

killrust enamel is ok, por 15 Is better

Unfortunately, due to logistics (no land vehicle) it'll be whatever Bunnings has which is either Dulux metal shield epoxy enamel or White knight epoxy enamel