Head lift mod

[Rainman229]

Well I have an Eldorado Bridge mill, That i picked up new in 01.
After long time I finally came to the conclusion that shoptask them self are no great help in solving my issues. So decided to fix my biggest issue my self.

My machine has/Had so much Z backlash that it made the machine useless for any 3d type work. So for the longest time it was my cut out machine. And if i couldn't cut it in one pass It was deemed useless.

My run out was with in .001 if the Quill stayed up. and didn't move. As it came down it got worse due to the Quill having a ton of play. Quill itself has about .009 slop
(Oh and if i tighten the Quill lock up it would only cause me to snap drive belts for the cnc.)

Backlash on the Quill was .026 . Which means no matter what i did everything was always at angle or stepped.

So with all these factors pissing me off. The guys at shoptask where some help. Together we came to the conclusion that the ballscrew kit would only solve 1 of 3 issues (would only solve the backlash issue)

So after About a year or 2 of living with this and since buying a syil Sx3 cnc. I decided it was time to fix it.

What i came up with is.
Ball screwing the Z quadra lift. And adding The cnc motor to that. But i went one step further. Since this requires the release of the 5th post.

I added a column from a seig x2 and its slide block. Creating a 5th post on the back motor side of the quadra lift. This stiffened it up and made the need for the 5th post un needed.












Well i went from .026 backlash on Z to a .0015 ( and thats cause i don't think theres enough balls in the ballscrew nut)

Just under 7" of z travel

.020 side to side play down to .001 (with out original 5th post locked down)

All the parts for this where cut on a syil SX3 cnc And on a manual Seig super X3


Edit
Forgot to add. Max fps on z rapid was 6fps Now its just under 18fps.

[sharpshooter90]

Rainman,
That's some clever thinking- adding that dovetail column- how much did they charge you for the part? I see you are also using that DC treadmill motor from Surplus center- how is the power and reliability? I am ordering a new Patriot machine soon, but planning on going to either a VFD or DC drive just to eliminate all the belt mechanism.

[Rainman229]

The X2 parts where $100 buxs at littlemachineshop And another $15 at grizzly For the out of stock parts (gib and screws)

Parts list
X2 column (part diagram number 68)
X2 Mount, Spindle Housing (part diagram number 63)
X2 Head gib (part diagram numberr 64)
Screws (part diagram number 43)
nuts ( part diagram number 29)

(2)5"x"5x 3/4" aluim plate to mount it.

Ballscrew was another $40 (turning down the ball screw to mount it was fun)


The x2 Mount, Spindle Housing was cut down to about 1.700" After milling



I'll try to get more pictures up and details.

As for the treadmill motor. It seemed to work fine and extremely quite ( compared to the stock motor and pulley setup)

Haven't had a chance to load test. Since i blew the controller when i dropped the potentiometer and it shorted out. As it was the last thing i need to mount.

Also need to mount some fans to cool the motor.

[digitalmdj]

Rainman you might want to try hard chromeing the quill and build it up to remove the clearence. There is a place in Sacramento ca that can do that. You just need a machine shop to do the finish grinding to fit it to the housing. I use a machine shop in fresno that ground it and then sent it to be chromed and finished ground it for me.

[Rainman229]

Rainman you might want to try hard chromeing the quill and build it up to remove the clearence. There is a place in Sacramento ca that can do that. You just need a machine shop to do the finish grinding to fit it to the housing. I use a machine shop in fresno that ground it and then sent it to be chromed and finished ground it for me.

Don't really think that will help as it tapered too. The play gets worse depending on where the quill is moved. Wasn't so bad when i first got. But after 7years. You do the math.

At this point I just want to get the new controller in test Run the whole thing.
I have a strut for it as well. But need to test run it to see if its need. I'll do test with it and with out though . To see.

[fastlanecafe]

After 7 years ( looks like you use it quite a bit) you probably have taper in the casting and on the quill. That is the old style head with the rack gear on the quill, so its probably not practical to try and fix it. I would say just run the quill all the way up and lock it in place and use the mill lift for the z axis. You could probably do fine if you put a larger stepper up there- maybe 1600 OZ/IN. You could also keep your eyes open for a cheap set of linear bearings & shafts on e-bay.

[Rainman229]

After 7 years ( looks like you use it quite a bit) you probably have taper in the casting and on the quill. That is the old style head with the rack gear on the quill, so its probably not practical to try and fix it. I would say just run the quill all the way up and lock it in place and use the mill lift for the z axis. You could probably do fine if you put a larger stepper up there- maybe 1600 OZ/IN. You could also keep your eyes open for a cheap set of linear bearings & shafts on e-bay.

Right now theres a 745 oz/in on the mill lift. Seems to be doing the job ok. My upgrade later. I was planing on putting liner bearings on it. But ran out of time. Need the machine back up for some work. That only it is set up for. Doing the liner bearings is going to be a challenge in itself. Theres barely enough room for them in the housing block. So which would mean reworking everthing.

[Rainman229]

Holy cow
Just got to test the dc motor under load. For starters i must wow. This is now the quietest machine i own. The dc motor works well. For a total cost of $45 plus shipping. (controller and motor). Getting rid of the tensioner pulley makes a big difference as well. That thing made more noise then it was worth. Also shaving about 6lbs off the spindle pulley made a difference. Oh and the z drive worked flawless. I'm in love with my shoptask again.

[Rainman229]

Got to run it some more today. Ran a 1/2 corner round end mill on it. Lets say night and day. Before when i ran the same setup. It would chatter so much that it would take anywhere between 1/2 hour to hour to clean it up on the belt sander. to get it all smooth out.

Now it's nearly smooth. If i wanted to pass on the belt sander and skip to buffing i could.
But ran it on the belt sander for 2 minutes. And it was all nice.

Why did i ever put this off for soo long?

[dgapilot]

Holy cow
Just got to test the dc motor under load. For starters i must wow. This is now the quietest machine i own. The dc motor works well. For a total cost of $45 plus shipping. (controller and motor).

I see the motors at Surplus Center, which controller did you use? Looks like a mod I may want to do.

David

[Rainman229]

This is the controller i'm using from surplus http://www.surpluscenter.com/item.as...tname=electric
your also going to need a 5k pot switch. ( do not do what i did. Do not hold the pot switch to test it out. 2 reasons 1 if you drop it and it shorts it blows the controller and it's loud. 2 if you accedently touch them it gives you a jolt big enough to wake you up.)
mount the pot before testing.

[dgapilot]

Rainman,
I saw t hat one, but was wondering if having to start the motor at slow/off and then increasing peed was a problem. I was also looking at
http://www.surpluscenter.com/item.as...tname=electric

Other than price, what advantage is there for the one you are using? I'm thinking of using Mach 3 to control speed via cnc4pc pot speed controler.

What are you using for reverse selection switch or relays?

David