Air blast

[MechanoMan]

I'd like to try making a nozzle to deliver an air blast to the cutting tip on my Taig. I've been spraying water-based lube by hand on the metal as we go but it's not doing all that well, the chips build up inside the cut during a deep rough and I have to spray them out anyways. Plus it's soaking the MDF I use as spoil underneath it and making it swell. I actually spent awhile with no lube and just kept the cut clean and cooled with the air hose pointed at the end of the bit manually and the results looked like it was going pretty great.

I looked at the little air blower I have spare:

Nice, no manual switch to hold down, and you can adjust airflow at the nozzle.

But I thought about it and the air hose I have off the compressor is heavy and not very flexible. If I mount it to the Taig headstock, I'm concerned that it'll weigh down the back of this blower tool, then rotate the tip of the tool upward as the headstock lifts and pulls on the hose. And there's not a lot of tolerance here, if the airstream misses the tip by 1/2" it's not worth much.

Is there a cleaner solution, like using a smaller, more flexible hose, something out of the hardware store? Anybody got a project page? Is "air blast" even the right term?

[ger21]

Get some Nylon tubing with quick release fittings from McMaster Carr. Very small and lightweight. Also, you can get a $15 air solenoid valve from Surplus Center to turn it on and off.

[MechanoMan]

Ah ok actually I see Harbor Freight's website has at least 3 types of coiled nylon air tubing. Surely they'll stock one in the stores that'll work.

[Halfdone]

Check out this stuff. It works great is easily controlled and stays were you put it. just run your flex coil to it and then you have great control at the tool. you can run air or liquid through it and it all snaps together so you can expand as needed. Not too pricey either.

http://www.grainger.com/Grainger/wwg/catalogPDF.shtml

Regards,

Mark

[MechanoMan]

mark95621, that link won't work, Grainger doesn't support catalog links. Do you mean the clear blue urethane coiled hose?

I ended up getting some of the yellow nylon coiled tubing at HFT. It's a bit rigid, I'd prefer something more floppy. It was only $5 though! I got a swivel coupler too so the hose won't apply torque to the tail end.

ger21, what solenoid valve at Surplus Center? They've got a lot!

[ger21]

https://www.surpluscenter.com/item.a...82&catname=air

[Halfdone]

Sorry guys the air line I was referring too is called "Loc Line". If you do a quick search on Grainger's website it will come up. Or go to page 3194 in their catalog. This is what I'm going to use on my machine when I get to that point.

Here is the manufacturers website for anyone interested.

http://www.loc-line.com/


Regards,

Mark

[MechanoMan]

Loc-line doesn't look appropriate for air blast. They don't handle high pressures, the highest is the 1/4" system at 50PSI. If you put the orifice at the start of the Loc-line, then the tubing will slow down the air's speed which decreases the effectiveness of the system. For liquid, I'm sure it's great.

I guess I could add a reg, but that'll again lower the effectiveness by quite a bit.

I looked at my air blower (the one pictured above) for awhile, and don't see a good way to mount it where I can adjust it to point at the tool tip. I mean the Taig's head has the T-slots but still I'm not sure how to build it. There's always the "bailing wire" solution.

[HelicopterJohn]

Visit my website and take a look at the gallery as I have some videos there that may give you some ideas for your project. I used a solenoid valve with a timer circuit that has the ability to meter the air in both duration between blasts and also the duration of each blast.

www.helicopterjohn.com

I have also attached a few pictures of a little manifold that I made that can dispense both air and fluid. It also has some loc line fittings on it including a valve that can adjust the flow rate. This particular one was made to use on a Bridgeport Mill but you could use this idea to adapt one for your purposes.

The bottom 2 pictures show how I hooked up a Heinrich foot pedal air switch to give momentary air blasts as needed. If you look close on the pictures you will see the lightweight nylon tubing I used for the air supply.

Just some information that may be of some value.

Feel free to send me a PM with any questions.

John

[MechanoMan]

Why go in blasts?
The little blower I have I was planning to leave going (which I guess isn't really a "blast"). The compressor will kick on once every 5 min or so which is no big deal. Seems like it'll keep the cutting zone cleaner and provide more cooling to the tip.

What pressure do you actually allow into the Loc-Line?

[HelicopterJohn]

Not every machining operation that I perform works well with air blasts.

I find that in machining delrin an intermittent blast of air does well to blow the chips away from the cutter path.

I use my programmable coolant (PCOOL) nozzle on most of my machining operations. It is a 20 position nozzle that can assign different heights of coolant or air application depending on the length of the tool currently in the spindle. The nice thing about the programmable air/coolant nozzle is that I can use the programmable height to better direct my air blasts in I choose that mode of operation.

You have already stated that the maximum operation pressure for the Loc Line fittings is 50 PSI. I use shop air line pressure and regulate it with the Loc Line valve (Blue and Orange fitting) in the above pictures. I don't use it on a continual basis as you propose but only on occasion to clear the chips when I am working on my Bridgeport. Also Loc Line offers different orifice size tips and also tips with multiple holes to give a wider spray pattern. The orifice size and how much you might restrict your air flow at the nozzle tip will depend on how much pressure is applied to the Loc Line hose.

Are you going to apply i.e. 100 PSI shop air to your material during machining operations on a continual basis or are you going to regulate the air flow prior to getting to your adjustable air nozzle?

I think you are on the right track and will find that the ability to adjust your air flow is key. The nylon type tubing and associated fittings that can be purchased at your local hydraulic supply store will work well to hook up your little adjustable blow gun. It is not very heavy and is pretty flexible.

Good Luck!

[Geof]

Originally Posted by MechanoMan Loc-line doesn't look appropriate for air blast. They don't handle high pressures, the highest is the 1/4" system at 50PSI.

I use an air blast for machining steel and never get above 25 psi; I think Locline should handle it fine.