Looking for detailed pictures of Quadralift

[Grego]

I'm looking for some detailed pictures of the quadralift assembly. I have a 1720 Gold that I am reassembling with the quadralift. The previous owner used the swivel head and had the quadralift in a box. Turns out I'm missing pieces. I have the posts and head mounted and sliding but I have no parts at all for raising and lowering the head. Apparently this also had a motor, which is gone. It was part of an estate so there's no chance of getting those parts back at this point.

I may just design my own lift but I really want to see the details of how Shoptask had their setup. Specifically how they ran the leadscrew through the plates and bolted everything together. I found a bunch of pictures on the web, that got the 4-post assembly together but nothing with details of the lift assembly. No exploded drawing exists from talking to someone with a manual.

Would someone be interested in taking some pictures of their Quadralift mechanism for me? even if the year/model isnt' exactly right it would give me something to go on. I thonk you can email through my name on this post.

Thanks,

Grego

[mixdenny]

Sounds like you do not have the acme threaded rods at all ? There are a couple of photos on my page that may help, otherwise let me know what details you need photographed.

http://home.wowway.com/~dthompson4389/Shoptask.html

It is fairly straightforward. There are two 5/8"-8 acme rods, and they screw into 2 nuts welded on the underside of the upper plate of the moving stage. There are bronze shoulder bushings in the top and bottom plates, the acme rods are turned down to ride in the bushings. The bottom of the shafts have two locking nuts, the top is secured by the belt drive pully. When the stage is leveled, the set screws for each pully are tightened to the acme rods to keep them in sync.

It did not come with a motor, although one was optional, my page shows the version I built. The standard method just has the two pullies linked by a toothed drive belt and a nut is on one of the shafts to turn with a wrench. The motor is far superior!

Denny

[Grego]

Aside from your mods, is that a stock quadralift? It looks different than mine in some ways. I'm sure I can rig up the twin lead screws, I just want to do it as painless as possible without takign the whole thing apart if possible. thanks for the pics, I had actually seen your pics on the web earlier and assumed you made the whole quadralift since it was different.

There are some things not adding up on my assembly. I'm wondering if the previous owner replaced the top plate because there are no holes for the two lead screws to protrude through and there is one bearing in the center of the plate. It also has evidence of a motor being mounted to drive a single leadscrew.

He may have been in the middle of some sort of modification and quit to go back to the swivel mount. It was an estate and they liquidated a large shop full of projects and materials, the parts could have easily gotten mixed in.

Thanks,

Greg

[mixdenny]

Mine is a stock Quadralift, in fact it is the very last one sold by Shoptask when they were closing them out a few years back. You have an earlier version with a single acme screw. I remember reading about it on the Shoptask forum. I believe it had accuracy problems caused by not having a lead screw on each side and a high lifting effort also.

The Quadralift is very inexpensively done using DOM tubing for the slides and ordinary round stock for the guides, so there is no precision alignment side to side and twin screws helps a lot. For instance, if I unhook my timing belt and turn only one screw, the stage cocks to one side, I think with the single screw it would be trying to do that all the time. Give John Taylor a call at Shoptask and ask him about setting it up, as I have not seen many pictures of that particular setup in many years reading the various forums.

Dennis

[mixdenny]

Well, you know what, I am wrong about the screws. I hate it when that happens! Have you seen tangoromeo's Bridgemill setup site at:

http://members.cox.net/tangoromeo/index.shtml

After looking it over, I see that the factory Bridgemill went back to the single lead screw. In particular, look at his "Fifth Column Mods" section, in the first two pictures you can see the single screw assembly, so I guess Shoptask got it to work after all. I'm not sure if your earlier version is the same, or if you somehow actually have the unit from a Bridgemill, but JT will be able to fill you in on it.

Dennis

[Grego]

The top plate of the sliding section is set up for two leadscrews. The bottom plate for the slider doesn't have holes for the leadscrews. The very top plate has the bearing for one.

I think in general this thing doesn't have to be accurate. You move it and lock it and that's it. I can't imagine moving it up and down in a setup like a Bridgeport, it would be way off.





Thanks for the info,

Greg

[fastlanecafe]

You might call the Shoptask folks and give them the serial # of the machine or the original owner's name. On the Shoptask forum there are a number of discussions about building your own quadra lift, and you might have an incomplete home build.

[mixdenny]

I've never seen one like yours, it's either a home built or maybe a prototype? Those collars that slide up and down the columns are far beefier than the Shoptask, which just uses DOM tubing tack welded in place.

As for accuracy moving up and down in the Z direction, that is all part of an careful setup. You first need to get the Quadradlift columns perfectly shimmed onto the machine headstock so that as the mill head moves up and down, it does not deviate in the X and Y planes. Then you need to tram the mill head by moving, jacking and shimming it around within the moving stage. You may even have to open up some of the mounting holes in the upper and lower plates of the stage to allow the mill head to move enough. Every bolt you tighten at this point moves it!

Mine is excellent in the Z direction and I took a lot of time to get it there. I can power up and down without tracking off, and I do it all the time.

I did a lot of testing with dial indicators while appplying an upward load on the quill as I built and aligned my unit, so I could see what was moving and what I had to do to prevent it. I found the Quadralift by itself was much sloppier than the standard Eldorado (despite what the factory claimed at the time) and everything depended on having the fifth column like the Bridgemill to stiffen it up. Now it is real stiff and a pleasure to use when taking heavy cuts in steel.

Dennis

[dahui]

Hi My Eldorado is a 2005 with a single screw on the quadralift. The four shafts are polished, solid, and mount with a bolt at each end.

[Grego]

Yea, it looks like I have some sort of Frankenlift. Rather than rebuild the entire drive assy right off the bat, I'm looking at a linear actuator. I started a new thread to see if anyone has any experience with them.

Greg

[sharpshooter90]

Looks to me like you do have a partially completed home built assembly. On our machine we had a single screw in the center of the lift mechanism and a brass nut in the mddle plate ( just above the mill head casting) on top of the screw was a square which had a handle for raising and lowering. I think you could make yours work easily by getting a piece of acme threaded rod from MSC and a matching nut. The nuts are steel and could be welded to the steel plate. All you need to do is drill a hole in the middle plate and one through the mill head casting for the screw to go into. The casting is hollow below, so its an easy drill. Probably won't cost more than 10-15.00 for the whole thing.

PS Our company had one in that middle east country with 4 letters. It was equipped with a 4 axes servo CNC and DRO and was used to make and repair parts for sniper rifles. Served us well and was still in action when I rotated home. I am looking for a used unit to set up in my home shop after my current tour.

[fastlanecafe]

Sharpshooter,
Were you there for Bush 1 or Bush 2? I found a used machine and am now doing my own CNC build up. So far everything is working fine, but the CNC is more complex than I first thought.