My question to you all is what do you think of THK style slides for use on the x any y-axis. I'm planing on (going to) build a cnc router. I was planning on using bearings on drill rod for the axis'. A recent trip to a local metals yard turned up something interesting in the scrap section. There before my eyes was some kind of slide assembly with 2 THK type rails and at least 2 slides to go along with. Very, very little rust, slid very smoothly, bolted down to a rigid frame (straight). I left them there because I didn't have a Torx bit to unbolt it all. Oh, Did I forget to mention that the rails were about 8 FEET long. Is worth going back for these parts for 30 bucks?

Run, don't walk...

Where exactly is did you say this scrap yard was again?

From the replies I take it that these type of slides are a good thing, an upgrade from a drill rod/ bearing idea?

THK are just about the best you can get. I paid nearly £1000 for my three sets of new THKs, 2000mm long, 700mm long and 300mm long. $30 is a steal

Mike

From the replies I take it that these type of slides are a good thing, an upgrade from a drill rod/ bearing idea?

Don't want to sound like a smartalic, but have you gotten them yet? How well do they slide? You want to trade for some 18" hardened ground stainless rails and ball bushings (just kidding there...unless ofcourse you really do, in which case I'll give you four, with eight bearings!)?

Hobbiest,
Tomorrow's work schedule looks like I will be able to take a late lunch and disappear back over to the metals yard. I doubt if anybody will get to them before I do. They are in a crate, under a pile of stuff, behind the last building, along a fence ----WHEW---
The rails were about half and half of rust. What was there was just a surface rust, not the deep pitting kind. I guess the rails must be hardened. In the spots where no rust was present, the slides moved freely and smooth. I didn't want to try the slides in the rusty areas for the fear of doing damage to the balls in the slides.

Well I made it back to the yard to get the stuff. It cost me a little more but I still came out ahead. If I had a digital camera there would be a picture for you all to see. They say a picture is worth a thousand words, I'll try to keep it less than that. The good stuff----(2) 80 1/2" THK rails, (4) slides, (1) Reliance Electric servo motor, (1) Ametek servo motor w/ planetary gearbox ( motor alone- 583 oz. in. torque), assorted bearings, assorted timing belts and pulleys, other odd and ends, and about 150 pounds of aluminum to be scrapped out. The aluminum frame (8"x8"x82"x3/8" C shape) had most of this stuff mounted to it. It was easier to just to buy the whole thing than standing there and taking off what I wanted. The Ametek motor/ gearbox is brand new and looks to be some kind of traction/drive motor that a wheel would bolt onto. Let's see, scrap the aluminum and sell off the big motor and I should come out ahead. Oh by the way, I paid $100 dollars for it all.

Good for you. What part (general is fine) of the country do you live in anyway? I have never seen anything like that in a scrapyard, in fact, we are not aloud to walk around the scrapyard here! Nice score! Keep the aly, and build the frame out of it.

Hobbiest,
I live in the midwest, St. Louis, Mo. to be more specific. That was the first time I had seen any thing like it before. I hope to find more, a couple of 36" ones would be great for the Y axis. It sure beats the drill rod/ bearings idea I had before. This place I go to is just plain unbelievable. There is stuff for the stuff, military leftovers, tooling left over from McDonnel Douglas (now Boeing), industrial buyouts....... and of course the regular metal supply. All this stuff is in a basement under the metal supply warehouse, 3-quansit huts, a warehouse and just scattered all about the yard outside. My first time there and since then they encourage me to go look arround. Talking to others there I have since found out there are other salvage places in town that I never even knew about, some aren't even in the phone book.

Hobbiest,
I live in the midwest, St. Louis, Mo. to be more specific. That was the first time I had seen any thing like it before. I hope to find more, a couple of 36" ones would be great for the Y axis. It sure beats the drill rod/ bearings idea I had before. This place I go to is just plain unbelievable. There is stuff for the stuff, military leftovers, tooling left over from McDonnel Douglas (now Boeing), industrial buyouts....... and of course the regular metal supply. All this stuff is in a basement under the metal supply warehouse, 3-quansit huts, a warehouse and just scattered all about the yard outside. My first time there and since then they encourage me to go look arround. Talking to others there I have since found out there are other salvage places in town that I never even knew about, some aren't even in the phone book.


do tell.. i am in tulsa and make my way up to st louis once in a while. might have to make a weekend trip up there

Congrats 2Much! Every once in a while incredible bargains can be found. I had been learning from various threads about the parts and pieces needed for a precise CNC machine. One of the regulars, Swede, has a nice website (www.5bears.com) and he has a section on the building of his mill. He was nice enough to give a description of the different types (grades) of THK rails-some are better than others. Good reference material!
I had no sooner read his page and learned what to look for than I stumbled upon an industrial surplus shop near where I live and went to check it out.
I was crawling around on racks of stuff and saw a pile of rails up high and out of site. Thirty four in total, all THK, all 80" long, 20mm, complete with two trucks each. They were all the HSR series-pretty good.
Cripes!
I went home and hit THK's site-these things were over $600 each new!
To make a long story short, I went back in a panic and made the guy an offer of $2,500 for the batch-money I didn't even have and the most I could borrow.
I was sure he would laugh at me but he actually thanked me for taking them off his hands: he didn't want to deal with packaging and shipping them. I was smiling from ear to ear all the way home.
I've recently sold some off here to pay off bills and to pay back my lender (thanks mom!)
By the way, I put five more on sale in the classifieds here today to help buy other parts for my projects. If anyone wants some nice rails, take a look.
If there is a moral to our stories I guess it is that eBay isn't the only place to find good parts and that sometimes you just get lucky.

Since the last time, I have found a couple of new places. First, this place is as the owner describes it " we are the bottom feeders of the industrial auction, if nobody wants it , we'll take it". There is more stuff for the stuff, every thing from fork lifts to fire trucks and in between. There are 3 acres under roof and another 5 acres of stuff outside. I did manage to find a large stepper motor, european manufacture, about a 5/8" shaft with an encoder. A lot of the info on the name plate was very faded. Only thing it was a 4 wire motor. Still debating if I should go back and get it.
The second place has more promise, an electronics recycler. I did find and get a large stepper though. It was a Japan Servo Co. model KP88M3-001, 3 volts at 2.5 degrees, 6-wire motor. I have yet to find any information regarding the torque rating on it. Anybody with any ideas as to it's rating? This recycle place is filled with pallets of shrink wrapped computers, printers, keyboards, copy machines and anything electronic. Oh, they let me have the motor for free and have no problems with coming back to look for more.

Evodyne,

Those rails and trucks that I picked up are THK HSR20's. I did see the ones that you had in the classifieds and would love to have a couple of them to make the y and z-axis'. I don't know if I'm just too cheap or just love to scrounge up stuff, the thrill of the hunt I guess. Since I found the THK rails, that's all I look for, I'm hooked. Swede's site is great, well done, I had visited it before on several occasions when I used to lurk in the shadows (no more). He is definitely a perfectionist, you can tell right away he loves what he does.

Well I broke down and bought a couple of stepper motors off of Ebay. In all of my scrounging I hadn't found a pair of matching motors. The motors that I got were used, made by Applied Motion Products Inc. Model# A093-ED0023, 450oz., 2.3 volt@ 5.5 amps, 6wire with a 3/8" shaft. I tried Googling the manufacture with no luck. I hated to get them without finding any specs or torque curves on them but the price I think was right, $147.00 for the both of them. Now I need to find belts and pulleys.