[SCzEngrgGroup]

I'm looking for a good, reliable source for *reasonably* priced bearing mounts of this style for 20mm ballscrews:

http://www.midwestmotionproducts.com...fk%20ver-1.pdf

Most of the ones I've found are just stupid expensive.

Anyone have any ideas?

Regards,
Ray L.

[lgalla]

Ray you are probably looking at BK/BF 15mm for a 20mm screw.
linearmotionbearings...Google search.ebay store.
A20mm set is $59.I didnot see a 15mm set but he has them.E-mail him to check stock
Larry
BTW they are scarry cheap

[SCzEngrgGroup]

Ray you are probably looking at BK/BF 15mm for a 20mm screw.
linearmotionbearings...Google search.ebay store.
A20mm set is $59.I didnot see a 15mm set but he has them.E-mail him to check stock
Larry
BTW they are scarry cheap

Thanks, I've contacted him. He doesn't have any of that style listed in any size, but it appears to me the BK/BF are just FK/FFs mounted into a block.

Regards,
Ray L.

[Jason3]

Ray, the square part that resembles the FK/FF type on a BF/BF is just the bearing retainer plate - the bearings are mounted in a bore in the main body of the block.

Keep an eye on the quality if you're going for the cheapies - mostly they're ok, but some aren't. Fortunately, most sellers of the cheap ones are pretty good about replacing faulty products. I stick with NSK's WBK series now, but they might not offer the best price/performance balance for your project.

Best regards,

Jason

[lgalla]

Hay Ray BK/BF are THK part numbers.I dought they are not knockoffs from linear...b.yer FK's are probably Chinese knockoffs too.
I have origional THK's,BK/BF and the BF floating side has a bearing made in China.
I don't understand,did you ask LMB for FK's or BK/BF,which they stock.If you want THK's they will be $200 to $300.The outher factor is are your screws machined for the blocks?If not...You thought the bearings were expencive sit down!!!
Larry

[SCzEngrgGroup]

Somebody pointed me to another good source:

www.misumiusa.com

Looks like decent quality, and reasonable prices.

Regards,
Ray L.

[tootalew]

The misumi is very nice....and they are located right next door to thk in shaumberg IL. I do not think that is a coincidence. I suspect many of each others products come from the same place.

[tootalew]

Larry,
You stated that if the balls screws were not machined for the block to sit ( I think you meant cost wise) I am considering buying a ballscrew that needs the ends machined, but am unsure of cost, or who to take it to.

[SCzEngrgGroup]

Larry,
You stated that if the balls screws were not machined for the block to sit ( I think you meant cost wise) I am considering buying a ballscrew that needs the ends machined, but am unsure of cost, or who to take it to.

The guy I've used several times is:

Robert Spalesh (or maybe Palesh...)
[email protected]
(440) 813-0920

He does excellent work, he's fast, and a lot cheaper than anyone else I know. He did all the screws for my knee mill conversion for about $200.

Regards,
Ray L.

[wildwestpat]

Hi Ray

I see a lot of concern being expressed about the cost of the angular contact bearing blocks. Since these were / are intended for use in precision machine construction a lot of the cost is not in the bearing but in the machining of the block. The block - or at least the better quality ones - will ensure that the shaft lines up parallel with the mounting face. This is worth it only if used with a floating block at the other end AND if the two blocks are mounted to ground flat faces known to be in the same plane as each other.

With home brew machines this is probably not going to be the case due to the method of construction and the methods used. Thus a lot of these precision bearing mount properties are wasted as the bearing mounts have to be shimmed to bring the bearings - shaft and motion travelled into alignment. So why not make your own bearing blocks assuming you are going to have to make adjustments to the mounting on assembly rather than pay through the nose for precission that was intended to give rapid bearing changes on production machines. Suitable bearings can be found in the attached see page 53 and onwards.

http://www.skf.com/files/151315.pdf

The cheapo suppliers have this bearing series on sale for arround $10 genuine SKF ones will cost more. I have purchased a number of these in non branded form and found that there is enough preloading built in to give no measurable movement in the radial direction and still have reasonable free movement in the axial considering mine have all been 2 RS types. With the pre loading set by the manufacturer the double row angular contact bearing is easy to mount.

Yes I know I don't like giving my money away - my excuse is that I have retired so am cash poor but time rich but I still don't have enough of the latter!

Regards

Pat

[Al_The_Man]

I use Misumi quite a bit, they even custom modify some items for a reasonable price.
Al.

[BobWarfield]

With home brew machines this is probably not going to be the case due to the method of construction and the methods used. Thus a lot of these precision bearing mount properties are wasted as the bearing mounts have to be shimmed to bring the bearings - shaft and motion travelled into alignment. So why not make your own bearing blocks assuming you are going to have to make adjustments to the mounting on assembly rather than pay through the nose for precission that was intended to give rapid bearing changes on production machines.

What he said.

FWIW, IH makes their own blocks that are integral to the motor mounts.

They work great and sure seem like a more elegant solution than trying to integrate a third party component.

Cheers,

BW

[SCzEngrgGroup]

What he said.

FWIW, IH makes their own blocks that are integral to the motor mounts.

They work great and sure seem like a more elegant solution than trying to integrate a third party component.

Cheers,

BW

The NSK stuff is interesting. I didn't realize there were AC bearings made so they could be properly duplexed without using custom ground pairs. That is impressive.

If I were making just one, I'd go with individual bearings, and making my own mounts. But this is for a product (a very low-cost knee mill quill drive), and the total cost of purchasing pre-built mounts is less than for making my own when I factor in the added machining time. But, I could still change my mind....

Has anyone here used AC bearings from VXB? They're certainly cheap, but how good are they? Are the double-row ones pre-loaded adequately for use as a ballscrew support? Are the singles made precisely enough to be duplexed with appropriate preload? How much are 7202s/6202s from NSK or another reputable manufacturer?

Regards,
Ray L.

[BobWarfield]

If you have to machine a bracket at all, even to mount the premade mounts, I'd seriously consider just doing the bearing mounts integral to it. The IH's look to me like they're done by circular interpolation, and again they work fine.

Ballscrews want to be mounted solidly and squarely, but they are not as demanding as spindle bearing mounts.

Cheers,

BW

[tootalew]

Bob,
What does IH stand for?

[SCzEngrgGroup]

Bob,
What does IH stand for?

IH = Industrial Hobbies (www.industrialhobbies.com). They make a very large and beefy RF45 mill.

Regards,
Ray L.

[M100]

Suitable bearings can be found in the attached see page 53 and onwards.

http://www.skf.com/files/151315.pdf

page 53...of a 52 page document?

[SCzEngrgGroup]

page 53...of a 52 page document?

Yeah, I've decided to make my own - it just packages so much better. I've got all the drawings for the whole quill drive done, just need to round up the materials. This is going to be very nice - smaller, cheaper, simpler than any knee mill quill drive I've seen yet.

Regards,
Ray L.

[wildwestpat]

Hi M100

Yes big O-OOOOps. should have been ref to page 34 onwards
Pat

[veteq]

Hey Ray,

If you want to go cheap:
http://www.bearing-fastener.com/Ball...pport-210.html

Think linearmotion2008 gets all the stuff here, same for worldofcnc, think 25 dollar a piece max.

otherwise misume for a normal price, the rest is expensive.....!!!

regards,

Roy