[cnczoner]

I need about 1/2" dia shaft with supports and open linear bearings -- what's a good source for these? Prices seem reasonable on ebay, but I have a distrust of ebay nowadays, and would prefer to get from a source where I can get more of the same later, rather than surplus/one-off's. McMaster is expensive. Any decent (hobby-type?) sources?

Thanks,
-Neil

[erikjgreen]

I was surprised to find that Amazon carries Thomson linear bearings... dunno which company actually gets the order/profit though.

I've found a lot of motion control stuff at a local surplus place, in parts and in machine form both. The only problem is finding 2 or three identical items when you need more than one...

Erik

[ger21]

try www.vxb.com

[cnczoner]

Wow, very surprised about Amazon too, but prices are on the high side. Some of the hits on Amazon are sold by VXB, Small Parts Inc, and others. For what I'm doing (very light duty), I won't need the ultimate high-end products. Never realized that VXB does linear motion components -- and their price aren't bad either.

SDP/SI has some decent linear ball bearing prices, but I can't find the matching pillow-block on their website, and no one's answering their engineering phone line today.

Thanks,
-Neil.

[Glacern]

Hi Neil,

We're planning to introduce linear motion components a few months from now. We'll be specializing in open-type supported linear motion systems, exactly what you're looking for, with an emphasis on quality, accuracy, and price. Our rail supports will be pre-drilled to directly mount to metric-sized aluminum T-slot extrusions, which we will also be selling. Our debut pricing will be extremely competitive.

For a 20mm rail system, estimate:
~$15.00/foot for supported rail (hardened shaft bolted to aluminum T-extrusion)
~$20.00 each for single aluminum pillow blocks
~$40.00 each for double blocks (two bearings in one block)

These can be directly bolted to extrusions with 30mm T-slot spacing, or drilled easily to fit inch-sized extrusions. We'll also be stocking 25mm and 30mm linear motion systems, also priced very competitively.

If you or anyone else is interested, please contact me via PM or email at [email protected]. We can bump up the priority of this project and stock our shelves in about a month.

Regards,
Sol
Glacern Machine Tools

[cnczoner]

Sol, How about 12mm?

[cnczoner]

BTW, is it generally acceptable to mix components from different suppliers? Everyone has tolerances, but would a 12mm bearing from a supplier generally be expected to work better (smoother, more accurate fit) with a 12mm shaft from the same supplier, or does it not matter (assuming they're comparatively the same tolerances, etc)?

[ger21]

Shouldn't matter with round shafts, as 12mm is 12mm. Although the clearance on the supports may be a little different.

[Glacern]

cnczoner,

Would 16mm or 20mm rails work in your application? Rail sizes below 20mm don't offer much in cost savings. Most of the router builders I've spoken to have requested 20-30mm rails for increased rigidity and load capacity.

Sol
Glacern Machine Tools

[the4thseal]

will your open blocks be adjustable like Thomson. sounds good can't wait.

[port_huon]

Although you mentioned a dislike of eBay, this seller has a good range of motion control products and has a pretty good reputation for quality and service.

[Glacern]

Yes, we will have the adjustable type available. A slit cut in one side of the pillow block will allow preload to be adjusted with a set screw.

Which diameters are you interested in? 25mm and 30mm offer high load capacities, and they don't cost that much more to manufacture than 20mm and 16mm systems.

[the4thseal]

as in most cases bigger is better, cost is always a concern so a sweet spot of max size and moderate cost.

[cnczoner]

16mm will work, even 20mm, but my app will be a gantry that will carry a 1-2 lb load, and no cutter (it's a pick & place system). So load will be very light, and I'd like to get as much speed as possible out of it, so keeping the moving parts light is better. Can you get 16mm?

BTW, what does the adjustment do? Reduce slop? Correct for misalignment? Or...???

[Glacern]

16mm will work, even 20mm, but my app will be a gantry that will carry a 1-2 lb load, and no cutter (it's a pick & place system). So load will be very light, and I'd like to get as much speed as possible out of it, so keeping the moving parts light is better. Can you get 16mm?

BTW, what does the adjustment do? Reduce slop? Correct for misalignment? Or...???

Yes we can get 16mm rails. Any specific lengths?

Open linear bearing bushings are like split sleeves. The slit and set screw in the aluminum pillow block pinch the bushings to eliminate slop and adjust for slight wear over time.

[cnczoner]

2 ft each. Also, I need to know the lengths of the pillow blocks (as this will limit my travel).

[schbrownie]

You can get what you need from PBC Linear.... give them a call at 1-800-962-8979

whenever I call, I usually ask for an application engineer. the last time I called, I spoke with "dave" and he was really great. If you tell him what you want, he can verbally tell you what each component costs so that you know approx what your total will be and what size bearing to order.

And since PBC makes their own bearings, you can be sure that what you get from them today, you'll be able to get from them years down the road.

p.s. Grainger and McMaster sell PBC bearings... but you pay a premium for them. There may be others, but Í know I've seen their stuff in both of those catalogs. (grainger does seem really high)

[cnczoner]

You can get what you need from PBC Linear.... give them a call at 1-800-962-8979

whenever I call, I usually ask for an application engineer. the last time I called, I spoke with "dave" and he was really great. ...

Easier said than done. I've tried to call him a few times already over the past few weeks, and left voicemails, but never heard back.