Thread: Bridgeport Clone Lubrication & Swarf

I removed a couple of parts:
- flexible line has tapered thread fittings,
- bush has parallel thread.

The 5/16 24 TPI UNF with 5/32 OD piping and 5/16 AF hex looks like a good bet to me.
Thanks a lot Mark and Stuart.

I note that the ARC Eurotrade site in the UK lists lubrication components, and full kits, with M8 x 1mm fittings and 4 mm pipe.
These look quite good and I would consider them if I cannot get piping and UNF as above.

Happy machining,
John.

I checked out the ARC Eurotrade site - approx AU$305 for a complete one-shot kit - delivered to Oz. Not too bad. I am interested in installing systems on my lathe and mill. I might start a new link once I have contacted some manufacturers in China - see what they could do it for.

Update:
I got some 5/16-24 UNF fittings and 5/32 (4 mm) tubing today from Lubrication Engineers in Prospect, Sydney.
They are Bijur agents and have some stock of meter units etc.
They do not have a sales counter, so ring or email before visiting.
$4 for a fitting with olive.

The metal protective sheath for the tubing still eludes me.
A flexible woven metallic water hose is close, but too stiff.

The ball screw supplier, Linear Bearings, suggested a Lithium soap grease as suitable lubrication.

The original Z-axis lead screw was oil from the manual pump.
It seems to me that the Lithium grease could be used here also.
Can anyone provide a good reason for not using grease ?

Happy machining,
John.

Originally Posted by electrosteam

Update:
The metal protective sheath for the tubing still eludes me.
A flexible woven metallic water hose is close, but too stiff.

Brake pipe off a motor bike if you can find someone that makes them. Off a car if you can't, although you might have to go up a size or two. You should be able to get some pretty S/S braid for a little extra bling.
Come to think of it why does the tubing need metal protection?(yes mine has it as well, which BTW is just a spring slipped over the tube). The aluminum pipe survives just find by itself.

Originally Posted by electrosteam

The ball screw supplier, Linear Bearings, suggested a Lithium soap grease as suitable lubrication.

The original Z-axis lead screw was oil from the manual pump.
It seems to me that the Lithium grease could be used here also.
Can anyone provide a good reason for not using grease ?

I dont like grease because I think oil flushes crud out better and faster. I would have thought use oil would be better at the speeds you will be turning.
BUT
1. They should know what they are talking about
2. The "right" oil probably only comes in 20l drums.
3. Maybe the bearing life is that long anyway that is doesn't matter that much either way?

Also, as its CNC a little backlash isn't going to hurt any is it?(unless it is enough that climb milling becomes a problem).

Hi John,
I looked up my old emails and found the message from linear motion bearings when I bought mine.

Quote
Hello,
Regarding the lubrication:
When lubricating grease is applied for lubrication, lithiumm soap base grease based or mineral oil is recommended. The densing of grease should be ISO VG32-100.
If wording temperaure is low, VG10 is recommended.
Thanks and Best Regards!
Chai
Unquote

If you look on cnc zone people will recomend using grease if it is going to be sealed and hard to get to. If you can supply oil it will be better as it will flush out grit in the ball nut, grease will make it stick to the screw.
It's up to you but I will be using oil on mine, when I get them installed.

Dave

Hi John,
Thought you might be interested in these pictures. He has converted his Bridgeport over to cnc and there are some good pictures of his oil line set up. He has also used 2 struts behind the knee screw.
Picasa Web Albums - Craig - CNC Mill Project#

Dave

Dave,
Thanks for that very interesting link on the Bridgeport CNC by Craig.
All the photos give me a good idea on how this style of mill is built, and some ideas on a CNC implementation.

I note that Craig is using oil on the ball screws.

The angled support bracket for the oil reservoir is exactly what I was considering yesterday.
The CNC on the Z-axis on my Kondia displaced the reservoir to a position further back.
But, the gas spring mounts just in front of the pump pull handle and the pull axis runs towards the back of the stepper motor - just cramped and uncomfortable.
The angled bracket cures the problem nicely.
(A new plastic reservoir with a pivoting handle would be even better - one day)

John.

No problem John
I found the link to that page in the Bridgeport section of cnc zone.
The name of the thread was "best way to clean rusty table and ball screws" if you need any more info about it.

Dave

Well I decided to go with oil for the ballscrews using a separate pump.

I purchased parts from Arc Eurotrade (UK) on 18Aug - delivered 26Aug.
(no photo because it is 1.5 MB, compressing does not seem to work at the moment)

The parts include reservoir, 4-way distributor manifold, selection of metering points, hose adaptors, plugs, plastic hose and metallic covering.
All the bits look quite OK, but the Nanjing Bijur Chinese instruction manual appears difficult.
Thankfully, AE included an English translation of the important parts and there is a glue-on label to overlay the Chinese instructions on the bowl.

GBPound 66 + 22 postage = $158 total.

Some aluminium plate today will provide the mounting bracket for the two pumps, one for the ballscrews and one for the slideways - I figure a two-handed pull should do it.

John.