need help with broken/missing autolube oil line on DM4400

[mmedina]

I just discovered something on my machine that's disconcerting to say the least: it appears that the autolube line that goes to my X and Y axes has been broken off since before I bought it (used) . The small diameter tube is sheared off at the fitting as you can see in the photo, and I do not know where it was supposed to connect to, since there has never been a piece of disconnected, dangling hose anywhere near the lower half of the machine. If you are a DM4400 user, please take a moment to describe to me where this hose is supposed to go, so that I can replace and re-connect it. I looked at the manual, but did not find any helpful info on the routing of the autolube lines. I am guessing Thanks!

[mmedina]

Found the hole for the oil line after I did a thorough cleaning back there. It is a few inches to the right of oil fitting.

The oil fittings and hoses/lines are metric, and are not available at auto parts places. (They had a limited amount of english fittings, but no metric fittings that are this small.) The lines are 4mm OD, and the fittings are M8 thread.

[2ferrous]

That is the main oil feed for the carriage. It feeds from the pump, through the back of the machine and through the Y axis valley (around the Y ball screw) up into the distribution block. This is a common failure on the 4000/4400's. Go to your local hydraulics supplier and buy some 5/32 poly line and new brass ferrules (also known as olives). You can reuse all the fittings.

Disassemble the fitting on the carriage and turn it 90degrees from its original orientation. The T thats about 12 inches from the pump is where the line for the carriage starts, so run a new line from there, along side the contol cable to the X axis stepper and over to the back of the carriage. Leave a few extra inches so the table can move its entire travel without streching the line. Then hook it up with a new ferrules and your ready to go. Prime the line a couple of times then let the machine sit running for an hour so the carriage and table gets the oil it needs right away before you start any machining.

I have pics if you need them

Timothy

[mmedina]

Thanks, Tim. I basically did what you said, except that I found some clear vinyl hose at an aquarium shop that fits snug over the 4mm aluminum tubing. I cut the aluminum tubing a few inches from the fitting, and slid the clear hose over the aluminum. I realize that the vinyl may not hold up long term because the way oil might soften or attack it somehow - in which case I will be going to a hydraulics store to get the hose and "olives" as you said. Again, thanks!

[olfoundryman]

Mmedina,
My apologies for taking so long to come back to you but I had trouble finding the necessary photos. As you can see from the photo of the yellow oiler tube I had exactly the same problem that you did. When I removed the Y axis ball screw cover plate the tube was in 4 or so pieces. It was so brittle and weak that by the time I got it out from around the ball screw it had fallen to bits completely – age and oil, I guess, had taken their toll on the plastic tube. I would guess that most Dyna 4400 machines have this problem. I would strongly advise all Dyna 4400 owners to remove the cover and check this tube as a matter of urgency. It is a most serious problem as this tube carries all the oil for the X and Y axis ball screws and slide ways. With it broken these things will run dry – wear, rust, and sticking will result. But even worse, this tube is at a low point on the machine so if broken will relieve the pressure provided by the oiling pump and thus the Z axis ball screw and slide ways will run dry too!
I obtained some PU tube 4 mm od 2.5 mm id (this is the size original used by Dyna) The tube I got was made by “Legris” and a few minutes being “one with Google” has confirmed that Legris products are available world wide. In the UK for example a 25 metre roll of this tube will set you back the equivalent of about US$20.00 – dirt cheap! Most suppliers of pneumatic products should carry this or similar tube.
I wound the tube around a crude wooden mandrel and heated it to about 140 deg C for 10 minutes in a fan forced oven, this set the tube in the coil shaped needed to go around the Y axis ball screw.
It is when I went to fit the new tube that my problems started! I did up the fitting that is tucked under the front of the column (a fitting cleverly positioned so you have to be a contortionist armed with some odd shaped spanners while leaning over the machine table to get at the fitting!) Just as the fitting got tight the “T” piece that it was being screwed into fell apart. This “T” piece - and the others on the machine, there are four – are made from a pressure diecast Zinc alloy. As any Metallurgist can tell you contamination of such alloys with even the minutest amounts of either Cadmium, Tin, or Lead causes corrosion at the grain boundaries within the cast product. This causes swelling of the casting and it slowly cracks apart. Depending on the level of contamination the process can take anywhere from weeks to many years. The photo of the four “T” pieces from my Dyna shows all of them to be badly cracked and I replaced all four. I doubt my Dyna is the only one to have fittings made from contaminated metal and I would urge all Dyna owners to also check out their fittings with a good magnifying glass. “Legris” of course also have these fittings. To get around my problem I ran some more of the 4 mm PU tube from the “T” piece nearest the self oiler through the small gap between the column and the electronics cabinet (this took a bit of doing!)into and down along the Y axis ball screw cavity joining it with the coiled PU tube that I had made via a push in fitting which I tied to the old broken fitting under the front of the column to keep it out of the way of the ball screw. This was a bit neater and safer than running the tube externally although obviously the later is easier.
Again to all DM 4400 owners as a matter of some urgency please check out this tube and all the fittings do not assume that because the level in the automatic oiler is going down that oil is getting to where it is needed.
Martin

[CNC Bill]

olfoundryman,
Those pics of the tees looks like mine. I've looked everywhere locally with no luck. Did you find the same type (3 female ends) or go to the compression type? Any part numbers? Thanks, Bill

[olfoundryman]

CNC Bill,
The fittings that I found were exact matches for the originals. The two photos attached show Firstly - a new three way fitting installed near the oil reservoir and as you can see it uses the original tube and attached olives and bushings The blue tube goes through the gap between the electronics cabinet and the machine column, from there it goes in the Y axis ball screw cavity and connects with the new curly tube I made up that goes around the Y axis ball screw, I joined these two under the front of the column (where one of the old cracked fittings had been) using a push in fitting. I don’t remember what brand of fitting the was but Legris have one suitable their
Part # 3106 04 00.
The second photo shows some spare of the fittings that I obtained.
Part #’s were T PKD04
2 Way PJ0404
Olive PB04
Bush PA04
These are Ishan Precision Industries Co Ltd Part numbers. Ishan are in Tiawan. There web site has a “contact us” bit so I guess you could ask them who near you is an agent. Note that these Ishan fittings are EXACTLY like the originals.
You can get the PU tube from Parker Legris they are in Mesa AR
The Part # for a 25 mt roll of 4mm od 2.5 mm id PU tube is 1025 U 04 xx where xx is 01 to 06 depending on the colour of the tube.
Vogel who seem to be represented at least by Devco Corp of Parsippany NJ have similar fittings but the T does not have the bolt hole.
Vogel Part #’s are T 504-008
Bush 404-002
Olive 404-001
I suggest just Goggling “Automatic lubrication fittings” I would be very surprised if you can not get them in the US - after all I found them here in Australia and within a few miles of where I live. Compared to the US, Australia is very much a place of “You can’t get it here”
I suspect that many more Dynas have these bad fittings so when you find a local source put the info on the forum to aid others.
Hope this helps.
Martin

[CNC Bill]

Martin,
That first picture is the the same one that broke on mine. I live in Northern California behind the Redwood Curtain about 90 minutes from the Oregon border. Needless to say, it's very hard to find anything I need within several hours from my house. What would we do without the internet!
On a positive note, I got my home built 3 phase rotary converter online today, and it booted the VFD right up.
Thank You for the info, I appreciate it and your time very much. Bill

[mmedina]

Martin, thank you for your detailed repsonse to my oil line problem. Sorry for the long delay in getting back to you and thanking you. We just recently had a baby over here - so we have been really busy over here. And in the moments in between being busy, we have been tired...

[CNC Bill]

Congratulations On The New Addition To Your Family! I hope everyone is well.