[MaNo]

Any updates/improvements in this project?

I plan to build a fog-less mister for my Sherline mill and lathe but would like to know if anyone has made some improvements to the basic design. I am particularly interested in the size of nozzle orifice.

Cheers

[Karl_T]

Any updates/improvements in this project?

I plan to build a fog-less mister for my Sherline mill and lathe but would like to know if anyone has made some improvements to the basic design. I am particularly interested in the size of nozzle orifice.

Cheers

Somebody went to using a small MIG gun tip for the nozzel. Cheap and saves making this part.

Karl

[MaNo]

Thanks Karl,
While I don't have a MIG tip I did get a small selection of nozzles with a blowgun I bought a while back. From 2mm, 1mm, down to 0.75mm. That small one I think they call 'needle' tip for some kind of valve on a sports ball.

Could even go down to 0.5 or 0.3 mm. I have managed to take the ball out of some empty metal ballpoint refills and the front section of those refills fits nicely into the 2mm tip.

I suppose it's now trial and error time although I feel that the 0.3 and 0.5mm tips will be too small to be of use

[Karl_T]

my nozzle is almost exactly 1mm. The unit has worked over ten years now with no maintenance

[otto_pjm]

Just as an FYI, if anyone is interested, I tried a similar build with all off the shelf parts for those that might have a CNC router but not a mill or lathe. (That's how I started out) I have one part I did use my lathe on and then solder the pieces, but I think it could have been drilled out and epoxy used instead for a very minimal tool build.
Link is here if you are interested, I based everything else on what I found here, so thanks for the great thread.



Pete

[MaNo]

I more or less complete the mister project and was just about buy the receptacle for the coolant when I remembered that I used to like my Coke 'flat' . I used to shake the PET bottle until it was rock-hard. I have no idea what the pressure was but it was undoubtedly much higher than the pressure in the mister system.

I then tested a bottle to 110 psi without problem......so for me the coolant container will be a soft drink PET bottle. The original bottle caps don't have a wide enough surface for the air/coolant fittings so I am now doing a 'cap' for the original bottle cap which can take those fittings.

The advantage of this setup is the fact that, apart from next to no cost (I do have to buy some softdrinks again) I can have bottles of various types of coolant at the ready.

[dogmeatk]

I then tested a bottle to 110 psi without problem......so for me the coolant container will be a soft drink PET bottle. The original bottle caps don't have a wide enough surface for the air/coolant fittings so I am now doing a 'cap' for the original bottle cap which can take those fittings.

Cool idea Mano .. I was wondering about doing this. Have you had success in machining a cap to take the required fittings? What did you find the thread pitch to be on the top cap? I cant find any of those type of water filters locally and don't want to order one.

I was going to weld up a tank from stainless, but I would quite prefer to bea able to see my fluid level at a glance

[MaNo]

Cool idea Mano .. I was wondering about doing this. Have you had success in machining a cap to take the required fittings? What did you find the thread pitch to be on the top cap? I cant find any of those type of water filters locally and don't want to order one.

I was going to weld up a tank from stainless, but I would quite prefer to bea able to see my fluid level at a glance

Can't find my camera to show you but it's really simple. Rather than trying to duplicate the thread I am using the original cap but made a 'cap' for the original. I used some stuff like Corian (brand of acrylic countertop material), made the pocket about 5mm bigger in diameter, about the same depth as the original and poured some epoxy into the pocket and pressed the original into it. Make sure you don't pour excessive epoxy, just enough to come almost to the top when pressing the original into the pocket.

When cured, drill your holes. I spaced them 3mm apart. I was lucky enough to have a drill bit of exactly the same diameter as the tubing. No sealant needed at that low a pressure.

My nozzle is from a metal ballpoint refill with the ball removed. Very fine and probably 0.3mm orifice. Shortly after doing that I discovered a long-necked and angled (gas?) welding tip at the hardware store with an orifice of maybe 0.5mm diameter. There is a '4' stamped on it, so maybe it's 0.4mm... dunno... but with my setup I am using 500ml (16oz) of surgical alcohol per 3-1/2 to 4 hours. I can probably do better once I receive the proper needle valve I ordered. Right now I am using some old piece of junk.

[LeeWay]

Just an FYI on this. It has been my experience that Kool Mist 77 will deteriorate Polycarbonate. It will make it crack, craze and become very brittle. It isn't supposed to do that, but I have seen it happen several times.

I would certainly check on the plastic type of the vessel and steer away from Kool Mist 77 or 78.
Metal or glass like what you see in water seps. for air lines would likely be a good choice.

Nice work on the system though. Very well done.

[MaNo]

Just an FYI on this. It has been my experience that Kool Mist 77 will deteriorate Polycarbonate. It will make it crack, craze and become very brittle. It isn't supposed to do that, but I have seen it happen several times.

I would certainly check on the plastic type of the vessel and steer away from Kool Mist 77 or 78.
Metal or glass like what you see in water seps. for air lines would likely be a good choice.

Nice work on the system though. Very well done.

Hmmm, good info....something to keep in mind but for me it doesn't come into play. PET Softdrink bottles are polyethylene (Polyethylene terephthalate) and I use isopropyl alcohol ..... as someone on this forum said, the place will smell like a distillery.....well, well, coming to think of it, I do believe overproof white rum is cheaper here

[ChrisAttebery]

I've been going back and forth about building one of these for a while. Well, I finished my 6000rpm spindle upgrade and now it's looking like a mandatory upgrade. I've ordered all the parts I need to build the system, but I'm not sure what coolant or lubricant to use in the system for use on aluminum. Any suggestions?

[Karl_T]

I've been going back and forth about building one of these for a while. Well, I finished my 6000rpm spindle upgrade and now it's looking like a mandatory upgrade. I've ordered all the parts I need to build the system, but I'm not sure what coolant or lubricant to use in the system for use on aluminum. Any suggestions?

On tiny fragile cutters, getting the chips out is key, not so much removing heat. I just use an air blast right at the cutter. YMMV

Karl

[Janice584]

I suppose it's now trial and error time although I feel that the 0.3 and 0.5mm tips will be too small to be of use

[ChrisAttebery]

After upgrading the motor on my G0704 I now have 6000rpm available. The machine cuts great with a 3F 3/8" AL end mill, but when I tried slotting with a 3/16" end mill I could see chips sticking to the walls and after a few minutes the end mill loaded up and broke. So I ordered all of the parts needed to make one of these misters.

My question is what coolant would you recommend to use on aluminum? I don't feel comfortable using alcohol since my water heater is only a few feet from my mill. I'd also like to avoid oils if possible. I like the results I get with Relton's A-9, but I hate cleaning it off of everything after I use it. The local tool shop carries Kool Mist 77 and 78. If I don't get any other suggestions I'll probably try 77.

Thanks,

Chris

[wwendorf]

I like the Koolmist that is environmentally friendly. Don't remember which number it is tho.

Wade

[ChrisAttebery]

I've been using an air blast and it worked fine up to 4000rpm, but once I sped up the spindle I started seeing this chip welding problem.

BTW: Wierd. I looked for my post from the other day and didn't see it so I reposted. Sorry for the double.

[ChrisAttebery]

I finished my mister last night. I think it came out pretty well. I'm pretty OCD about clutter, but I think it is a pretty clean setup. I picked up a Loc-line kit this morning so I'll swap the brass tubing for a 1/8" PTC connector and run the line inside the Loc-line. Someone did that on a thread I saw somewhere but I can't find it now. I also picked up a gallon of Kool Mist 77 so I should be good to go for the next year or two.

BTW: I have a regulator on my compressor, so I set it to 40PSI and set the regulator on the mister air line to 10PSI. It misted OK, but I don't know that it will clear chips that well. I tried 60/20 and that seemed better, but I still think I want more volume. I had a .060"ID nozzle on my air blast setup and it worked well at around 5PSI so I'll try it on the mister and see how that works.






Chris

[ex-egll]

Hi, I am thinking about building the mister, but I have a "blank spot" in the old grey matter about the nozzle assembly. In the picture from Chris in the previous post, coming out of the mixer block there appears to be a brass tube with the nozzle on the end. Are the dimensions of this tube critical ir is it just a means of getting the air / coolant mixture to the end nozzle with its narrow (.04") opening?

Thanks for any help

ex-egll

[Fastest1]

The tube is just for transporting the already mixed air and coolant, the valve directly above is for metering the coolant.

[ex-egll]

Thanks, that makes life a lot simpler!

ex-egll