[Zephrant]

I've been looking at commercial pillow blocks, and rail mounts, and determined that they are way to expensive for what they are. I am thinking that with access to a mill, it should be pretty easy to make my own.

I'm concerned about hitting the ID of the pillow block for the correct fit to the bearing though.

Has anyone built their own blocks and inserted a commercial bearing?

Zeph

[balsaman]

If this counts...



Eric

[Zephrant]

That looks cool. Is it as simple as turning down the end of the shaft to a precise dia. (+/- 0.001" or so) then sliding on a thrust bearing, inserting it in to the block, and sliding on the other thrust bearing? I've seen where one person uses a ny-lock nut to hold the thrust bearings on, how are you doing it?

Should the bearings be so tight you have to chill the rod and heat the bearings to get them on?

Zeph

[HomeCNC]

I just finished boaring my bearing holes in my new CNC router. It is very easy with a boaring head attachment for a mill. Go to Enco or MSC

[balsaman]

It's actually just a delrin block drilled for a tight fit holding two regular ball bearings. The acme rod was turned to 5/16" and that's a 5/16 nylock nut that holds it all in there. It actually works great for my aplication. (just a cnc hobby wood router).

Eric

[coherent]

Do you mean bearing holder blocks and rail support for round shafting and bearings? I'm in the process of making some now. I think you can come up with some fairly good ones using aluminum, derin, uhmw or pvc. If nothing else, a good oak or maple would make a bearing holder or shaft support that would last years. Standard woodworking tools suffice. It helps if you have a drill press. Shaft supports can be as simple as taking a flat square of material and drilling a hole the size of the OD of the shaft (sized for a tight fit) and mounting it on the inside wall at each end of your machine. A larger rectangle shaped block, fashioned the same way and then split along one side and drilled for nuts and bolt (to close/secure the split portion) will hold a round linear bearing tightly and offer easy removal and numerous mounting and/or taping options. Keep it simple and make it sturdy and it'll work great! Sorry if this wasn't what you meant, or is info you already knew, but want to pass on that you don't have to spend the big bucks to make this stuff work accurately. It may not look as pretty, but it works! Once you have a working machine, use it to make your fancy parts!
-Marc

[georgebarr]

I can use a square hollow metal bar as the housing for the pillow block. Use any round bearing. You can even use the ball-bearing-less bearings which are the cheapest as compared with ball bearing types. You can drive a screw into the metal bar which makes contact with the bearing to secure the bearing within the metal bar housing. I saw a picture of this in itemamerica.com. Here is the picture. However, instead of using a plain hollow square metal bar as the housing, it uses a piece of aluminum extrusion that is precut. This setup would be the least expensive, fastest done, with most accuracy that I can think of. I'm sure there are cheaper ways but they would not be accurate. See the picture to see what I am talking about. The only problem is that it might not readily work with rails that support the round rod. But maybe there is a way around that.

Here is the picture found at: http://home.mminternet.com/~georgeb/item_bearing2b.bmp
Maybe someone can include this in a message. It is a big file.

[ToyMaker]

The picture that georgebarr posted is just one step shy of the ideal bearing support. It only has a set screw on one side. If you drill and tap all four sides you have what is a (very) basic 4 jaw chuck!
All your end plate alignment problems evaporate.
And, thinking about it for a moment, you could probably do something similar on the table drive plate too. Then radial adjustments of the nut as fine as frog hair are easy .

robotic regards,

Tom

[WOODKNACK]

where would one get aluminum extrution like the one in the photo above? I have been looking on the net for the stuff.

[georgebarr]

To answer your question about aluminum extrusion, you can find some at http://8020.net, http://itemamerica.com (expensive), and http://www.futuraind.com.

[WOODKNACK]

Boy that looks like the cats meow! you could build a whole machine out of that stuff. even the slides!

[ger21]

Woodknack, take a look here for plans

http://www.campbelldesigns.com/

Gerry

[HuFlungDung]

Reid Tool supply also handles the aluminum extrusions. There are a ton of accessories for this stuff, including plastic lined slide blocks and stuff. Contact them for a catalogue.

[boxwood]

Here you go these guys run this auction over and over, I have emailed and they do have longer and bigger sizes and quite a bit cheaper than new, this will probably be my next machine material
http://cgi.ebay.com/ws/eBayISAPI.dll...&category=1267

[WOODKNACK]

hey HuFlungDung,
Nice name by the way! cuckery... hehehehehe. Anyway what is the address to reid tool supply? Thanks

[kdoney]

I don't claim to be an expert and I thought milling my own pillow blocks should be easy so I tried for 2 weeks and couldn't get them to where they wouldn't bind. Of course I was building a dual x axis and had to tie 4 of them together ( 2 on each rail)

[wms]

Sorry Hu is not here.

Reid tool supply company
www.reidtool.com.
800-438-1145
231-777-3951
2265 Black Creek Road
Muskegon,MI 49444-2684


HU's shadow (not the control on his mill)

[Zephrant]

What I am looking for are blocks to hold linear bearings, that slide on 3/4" steel shaft (continuously supported).

I was thinking of starting with a block of AL, drill/mill for the bearing and clearance slot, and milling steps in each side to allow for bolting on to the gantry. If I leave the bolt holes large enough, can I loosely assemble the gantry then tighten down all the blocks? The slightly oversize mounting holes allow movement in one axis at least. As long as I can drill straight, the other axis should be fine. If not, I can shim a little.

Sound feasible?

Zeph

[kdoney]

I can send you 4 billet aluminum pillow blocks I tried to get to work. These where drilled, bored and ground to what I thought where precise dimensions. Each pillow block would move smoothly down the linear shaft until I tried to tighted the gantry to two of them spanning two different shafts. Then they would bind. From what I was told, the interior of the pillow block (where the bearing goes) is not a straight bore hole but is slightly hour glass shaped so when the bearing needs to align it can move in the pillow block. I can't really say. I never got mine to work. Good luck.
Kevin

[ger21]

Here's a picture of my Z-axis/Router mount.

http://mywebpages.comcast.net/ger21/CNC/z1.jpg

It's baltic birch plywood with 1-1/4" holes for the bearings for 3/4" shaft. I haven't finished the gantry with the shaft mounts yet, but I dont see any problems with binding. I drilled the top and bottom mounts while they were attached together. Then I attached one to my shaft mounting plates and clamped it to my drill press with the 1-1/4" bit in the hole. Switched to 3/4" bit, and drilled shaft holes without moving plates. My bearings have some adjustment and they are a little sloppy on their own, but if I wrap a layer of tape around them and carefully slide them into the holes, they ride very snug on the shafts.

Gerry