March 20, 2013
This item is on sale for just under $30 this week only, so get yours now!
You'll be glad you did.
I am 6 months late for this post, I bought and installed the LMS air spring. I was not impressed except for the added height achieved with the new rack. After a month or so I removed the air spring and added a counter weight. The counter weight works better than the air spring in my opinion.The directions as noted by the administrator are wrong and the dimensions he gives are correct.
With a counter weight you can use the full height of the rack, from top to table .The air spring prevents this to an extent.
February 16, 2011
February 16, 2011
So, last month I bought the kit. $43 shipped. I should mention that this is for the X2 (mine is a Grizzly). Comes with all the parts necessary, and the finish on the parts is like other LMS offerings. Black oxide, and fairly well made. No burrs or sharp edges, good threads, holes nicely chamfered, etc. Nothing that couldn't be made by the home machinist (except maybe the rack), but it's certainly easier to just buy and install. Also comes with a longer rack, providing more travel. That alone is nearly worth the cost of the kit, and is the main reason I bought mine*. You can raise the head right to the very top, and down so it nearly touches the bed. It goes all the way down to the lowest part of the column. The parts are completely satisfactory.
Gas strut is pretty strong. After install, it holds the head without using the lock, but won't raise the head on it's own. Pretty well suited to the task. I wouldn't try to mill without locking the head, but you can't with the stock setup either. Again, satisified with this.
The instructions, however, are WRONG. While clearly written, and including templates and pictures for an easy install, it has one glaring error. I'll get to that in a minute. First off, you remove the old rack (2 screws) and replace it with the new one (4 screws). You do not have to remove the head to do it. So far, so good. Drill a hole in the column near the top for the stop. Tap and install the stop. Cast iron taps easily and cleanly. Again, all good. Then you drill and tap 2 holes in the top of the head for the bracket that holds the bar which attaches to the strut. They even provide a template, which I found to be pretty much right on, but you have to be careful, as the centerlines in the template are not on the centers of the holes. Not a huge deal, but it could cause problems if you don't spot it correctly. Careful measurement will get your holes in the right location, and since the part has clearance for the screws, you have some margin of error.
Now we come to the problem. They say to drill a hole for the end of the strut down 12" from the top of the column, on the back. NO! Doing it this way causes the strut to bottom out before the head gets to the bottom. This limits travel by about 2.5". Since I use collets for my mills, this means the head doesn't go down as far as it should, and severely limits the use of the mill for actual milling. The bar that attaches to the strut has plenty of clearance, and the strut has plenty of travel. This hole should be 14.5" down from the top of the column. This restores full travel of the head.
The head needs to be locked and the stock counterbalance arm removed before installation of the gas strut, because of clearance. The kit says to install the strut first, but you can't tighten up the nut properly with the factory bar in place. If you try, you risk damaging the shaft of the strut. It would be nice if they included some sort of cover for the holes (even a sticker would work), just to clean things up a bit, but that's a minor niggle. I plan on using plugs like you find at auto parts stores just to make it look more clean. I also plan on cutting a hole in the colum cover and reinstalling that, just for appearances.
Other than that, I really like the setup. More vertical travel is very nice. Having the head more evenly counterbalanced is great. It actually appears to eliminate the dreaded "head drop" when using the fine feed, and so makes it more accurate. Essentially, it removes most of the backlash, making for better control. Fit and finish of the parts is very good, making for a kit that appears factory, instead of tacked on.
Would I buy it again? Yes. Do I recommend it? Absolutely. It's one of those really minor things like the tailstock camlock kit. Once you have it, you'll wonder why you didn't do it sooner. For the extra travel, it's worth it. For the elimination of the head drop problem it's nearly indespensable.
* You can purchase the rack separately, but without the spring kit, the factory counterbalance limits the travel of the head, negating most of the longer rack. For less than 45 bucks, I'd recommend the kit.