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View Full Version : Standard over the counter V-rollers and rails


Gerald_D
Sun 05 November 2006, 00:23
Some history, as I see it (maybe wrong)...

Bishop Wisecarver (http://www.bwc.com/) invented and patented (http://patimg1.uspto.gov/.piw?Docid=03661431&homeurl=http%3A%2F%2Fpatft.uspto.gov%2Fnetacgi%2Fn ph-Parser%3FSect2%3DPTO1%2526Sect2%3DHITOFF%2526p%3D1 %2526u%3D%25252Fnetahtml%25252Fsearch-bool.html%2526r%3D1%2526f%3DG%2526l%3D50%2526d%3DP ALL%2526S1%3D3661431.WKU.%2526OS%3DPN%2F3661431%25 26RS%3DPN%2F3661431&PageNum=&Rtype=&SectionNum=&idkey=8C39A3FF47DE) the dual-vee roller in 1970. They did not invent the V-roller that has been around much longer. Somewhere along the line they sold their "technology" to Hepco (http://www.hepcomotion.com/) who does international production and distribution, but BWC retained the USA market for themselves. Patents have long expired (and didn't apply to the standard V-roller anyway). Yitong (http://www.yi-tong.com/) does a good line of rollers, but not rails. I guess the Yitong stockists can recommend rail suppliers? Here is also QBC (http://www.qbcbearings.com/RFQ/B610HTML/B610P147.html) (use Prev/Next buttons on that page).

Anyway, the BWC/Hepco guys have been extremely successful in building the Dual-Vee brand, and command very high prices. The funny thing is that the older "single-vee" roller is pushed into the darkness somewhere, even though very few people use the outer V of the dual-vee. Where are the simple "single-vee" wheel suppliers?

Greg Holt
Thu 16 November 2006, 01:07
I just asked Yitong for a price for eight #2 vee rollers. $49.90 each

Including $30 postage they came to US$429.20 ..... WOW!!!

"IMService" has them on their website for $12 each, times eight and say $50 for postage makes $146

There can't be that much difference in quality....can there??????

Gerald_D
Thu 16 November 2006, 02:38
IMService is selling the #2 size wheel - they do not list the #3 size wheel needed by MechMate.

Remember that Yitong is an OEM producing these bearings by the 1000's - they are not a mail order house. I am fairly sure that IMService buys in bulk from Yitong - quality is not an issue here.

DocTanner
Thu 16 November 2006, 13:58
I bought 16 of the GW3 Guide wheels for $16.95 Standard bushings $2.80 Eccentrix bushings $3.40 www.superiorbearing.com (http://www.superiorbearing.com)

Greg Waggy
Thu 16 November 2006, 14:08
Doc, was that $16.95 each?

DocTanner
Thu 16 November 2006, 14:18
Greg,
Yes, For 16 GW3 and 8 regular and 8 eccentric bushings = $312.80 + shipping. Good service!

fabrica
Thu 16 November 2006, 20:35
I am still trying to negotiate a deal with YITONG for rollers. I feel that if we could get a price of around UD $ 30 per piece inclusive of (Courior) delivery charges to any part of the world.

Are you people happy with this price.

Gerald_D
Thu 16 November 2006, 21:46
Doc, that it very useful information!

Fabrica, $30 is much too high if they are available in Ohio for $16.95.

vadeem
Thu 16 November 2006, 21:58
That price from Superior looks to be the best so far, short of us doing a bulk buy from Yitong.

Do we have enough people even to do a bulk buy?

Greg Waggy
Fri 17 November 2006, 19:58
I'm talking to a machinist friend of mine about making the pressed in "V" rollers. As soon as he figures it out, maybe he will provide W3 "V" roller bearings for around $15.00 each. I'll let you know.

Gerald_D
Fri 17 November 2006, 22:13
Greg, tell your machinist friend that you don't need the outer V of the dual-vee concept on the roller. That part is probably the most difficult to machine, adds to the cost, and we don't use it.

The off-center V of my design leaves a nice shoulder to grip in a lathe chuck - your machinist may consider this one the easiest to work with.

Greg Waggy
Fri 17 November 2006, 22:28
Will let you know, Gerald, He's an old aircraft machinist so he like to be precise. He worked for the U.S. Air Force and came head to head with engineers as they stuff on paper didn't work in the real world. I like your shoulder, it gives some space. I'll let you know what he/we come up with. Heck, I may go buy a small lathe and make it CNC and do it myself. If I could turn out 8 or 10 at a time, I'd be happy just to pay for the lathe, I've got the rest,

Greg

Brian_B
Sat 23 December 2006, 07:49
Hi all,

I've been trading emails with Donald Neisler out of Texas - Donald was nice enough to find a local laser fabrication shop to cut the parts for the Y-gantry and car that gave a substantial discount for more than one off quantities. When I spoke with him yesterday, he had seven confirmed orders for a set of parts, and another 3-5 sitting on the fence. Even when adding in shipping, by ordering my set through Donald I was able to save over $200 when comparing prices I was quoted in the Boston area.

Anyway, it got me to thinking about other components for the MechMate that might generate a price break if ordered in quantity.

The first thing I've investigated are the V-rollers and bushings. The best price anyone had found so far was $16.95 for the GW3X roller from Superior Bearing out of Ohio. We owe that bit of info to DocTanner, also out of Texas.

I sent an email of inquiry to Superior Bearing asking what kind of quantity price breaks they have. They responded almost immediately and with not insignificant discounts

"There are price breaks at qty 50/100/500pcs. This is generally for single
purchases, but I will discount if you can somehow link these jobs together.
I can ship international also."

"Here is the pricing:

GW3X: 1-49 = $16.95; 50-99 = $16.10; 100+ = $14.49
B3: 1-49 = $1.80; 50-99 = $1.71; 100+ = $1.54
B3X: 1-49 = $3.40; 50-99 = 3.23; 100+ = $2.91

Delivery is from stock."

B3 are the centered Bushings; B3X are the eccentric, adjustable bushings.

If we can get nine or more people to order sets of 12 rollers/bushings, it amounts of a savings of 14.5%, or $32.64 per set ($225 vs $192,36). This doesn't include shipping.

It then occurred to me that there might be other ways to save money by buying in "communal" quantities - how many stepper motors would we need to order to get a discount? Gecko drivers? Z-slide plates? Springs? Racks and pinions? Etc. etc.....

If any of you have been talking to suppliers, can you go back to them and ask about quantity discounts (we'd probably be looking at quantities for 10-20 MechMates at the moment, but if we can decrease the build price by 15-20% via quantity buying, we may be able to induce some fence sitters to jump in) and post the responses you receive on the site.

Merry Xmas to all

Brian

Bill McGuire
Sat 23 December 2006, 11:57
Great idea...
Another benefit comes when some of us novices get confused with the technical nuances (#2 or #3 wheels). We can get the discounts and not have to return a wrong product that we purchased by mistake due to lack of knowledge....

Brian_B
Tue 26 December 2006, 14:34
Gerald,

I traded emails with Donald today - he indicates that he has confirmed orders for 10 sets of laser cut parts!

Anyway, that number of MechMates would put us over the magic number of 100 to get a 15% discount on V-wheels from Superior Bearing.

So, I just wanted to confirm that the MechMate, as currently configured, would require a total of 12 #3 V-wheels.

I also was wondering, if we choose to order the bushings from Superior as well (at only several dollars each, even for the eccentric ones, I'd be hard pressed to make them myself for that little!), would you recommend ordering all straight bushings, all eccentric, or half and half?

By the way, Donald has offered to use his website to set up the bulk order of the v-wheels and bushings.

Brian

Bill McGuire
Tue 26 December 2006, 15:13
Thanks for the info, Brian...
Hope everyone had a wonderful Christmas...

Gerald_D
Tue 26 December 2006, 23:15
Brian, 12 off #3 V-wheels is correct, but I still can't figure out how to use any of the ready-made bushings. The MechMate plans call for no bushings on the X and Y axes - a 12mm bolt is used. The only bushings are on the Z-axis where eccentric adjustment is needed.

The big problem I have with the ready-made bushings relates to the seals of those bearings/wheels. The BishopWisecarver seals appear to be flush with the outer face and so it is tricky to screw a wheel flat against a surface. For the MechMate Z-axis, the wheel must be raised above the surface by a set distance and a pedestal is used. This pedestal must only carry on the inner hub of the wheel and not touch the seal. How would the ready-made eccentric bushing achieve this?

Brian_B
Wed 27 December 2006, 08:31
That is a good question, so I posed it to the Superior Bushing tech people. I'll let you know what they say.

Brian_B
Wed 27 December 2006, 14:00
Gerald,

Here is the response I got from Superior Bearings:

The inner race is slightly wider (thicker) than the outer race. You can
mount a bearing flush to a clean hard surface and it will rotate freely.
The bushings can be used with the head on either side of the bearing.
Generally you have stationary bushings on one side of the assembly,
preferably the side that carries the load, and the adjustable bushings are
used on the opposite side to take the "slop" out of the assembly. Usually
there are an equal number of stationary and adjustable bushings.

Gerald_D
Wed 27 December 2006, 23:05
Very interesting. I wasn't aware of the difference of width between the races. (Is it mentioned in the literature from the various suppliers of these bearings?)

My only experience was where I received a new machine that had washers between the rollers and the mounting face. The washers were touching the seals and I could feel that the rollers were "stiff" when tightened. It could have been that they were poor washers.

The quality and use of washers could merit a whole thread by itself......

"Generally you have stationary bushings on one side of the assembly,
preferably the side that carries the load, and the adjustable bushings are
used on the opposite side to take the "slop" out of the assembly. Usually
there are an equal number of stationary and adjustable bushings"
The Z-slide doesn't have a particular load side. I more or less use the eccentrics on one side to set the slide perpendicular to the table, and those on the other side to put on-preload.

Brian_B
Thu 28 December 2006, 08:00
Hi Gerald,

I could not find the above information just going through either the Superior Bearing or Bishop Wisecarver sites - that doesn't mean it isn't there, just that I couldn't find it!

In terms of what washers to use, I'd suggest 'fixturing' washers. These are typically used by machinists and tool/die and jig makers for precise offset positioning and shimming. These are not stamped, but rather machined to exact thickness and inside/outside diameters.

I looked at the McMaster Carr website (http://www.mcmaster.com/) and found 5 different thicknesses for 12mm id washers: .1, .2, .3, .5 and 1.0 mm - and since these are precise, they can be stacked for any thickness you might need. As an example, see:
http://www.mcmaster.com/param/asp/psearch.asp?FAM=washers&FT_138=63199&FT_104=14 1&FT_3696=164414&FT_3776=165367&FT_147=60655&FT_555=24699&FT_424=24705&FT_3797=1 64124&FT_3551=155473&FT_556=24637&FT_518=125969&FT_2234=172453&ppe=10&session=wa shers (http://www.mcmaster.com/param/asp/psearch.asp?FAM=washers&FT_138=63199&FT_104=141&FT_3696=164414&FT_3776=165367&FT_147=60655&FT_555=24699&FT_424=24705&FT_3797=164124&FT_3551=155473&FT_556=24637&FT_518=125969&FT_2234=172453&ppe=10&session=washers);138=63199;104=141;3696=164414;377 6=165367;M;I

The prices for such washers are not bad - generally less than $10 per bag of 50 for each size. To buy a bag of each thickness works out to just over $40. Just be careful only to buy DIN certified steel - they also sell uncertified stainless steel ones!

Gerald_D
Thu 28 December 2006, 09:22
Brian, the "Shim Washers" mentioned on drawing M120100A are the "Fixturing Washers" that you talk of. Would suggest getting only 0.1mm and 0.3mm thicknesses.

Also on that drawing, it can be seen that the V-roller is held between 2 nuts. The slight chamfer on the nut face clears the seals.

Brian_B
Thu 28 December 2006, 10:12
Just when you thought it was safe to go back in the water ....

A follow-up email from Superior Bearings:



I went back and looked at the bearings again and I do not think it is
correct that they can mount flush against a flat surface and still rotate.
The inner and outer race are the same thickness. The seal is thinner and
will not interfere.

Some customers use a standard washer and we do have some customers that
modify the head height of the standard bushings to achieve the standoff they
need.

Sorry for the confusion, let me know if I can do anything else to help.



I am going to see if I can get accurate dxf drawings from them for use in our planning.

Gerald_D
Thu 28 December 2006, 15:14
No problem Brian, the plans have always assumed that the wheels cannot be flush mounted. That's why I supplied plans for eccentric bushings that will support the wheels correctly.

reza forushani
Fri 09 February 2007, 15:26
OK I got this from superior bearings, please help me

Are you planning to use only the B3X adjustable bushing? Typical assembly is to have B3 stationary bushing on one side and B3X adjustable bushings on the opposite side to be able to adjust preload. If you put adjustable bushings on both sides, it can sometimes be difficult to adjust correctly. Brian told me that you were planning to use B3X adjustable on all 4 locations on the Z axis as it can be tricky to adjust. I just want to make sure I supply you the correct products.

Also, we can supply standard ball bearings as well. I do not know all the bearings used on this machine, but I can offer the following:

6001-2RSR: $2.37ea made by ORS, $0.84each made in China
So, what should I order?

Thanks

reza forushani
Fri 09 February 2007, 15:46
How many rollers, regualr bushings and eccentric bushings do I need to order
GW3X -12
B3 - 6
B3X - 6
Is this right?

DocTanner
Fri 09 February 2007, 16:26
Reza,
The bolts for the X Gantry and the Y Car act as the bushing for 8 of the guide wheels.
When you order bearings, you need a total of
12 pieces GW3X - Size 3 Guide Wheels
4 pieces B3X - Size 3 Bushing - Adjustable
I have had no trouble aligning the Z using the adjustable bushings.

If there is a concern, purchase 2 of the Size 3 Bushings - Stationary, for $1.80 each.

NOTE:---->> Double check the laser marks on the spider. Test fit the bearings to the Z-Plate prior to drilling.

DocTanner

Gerald_D
Fri 09 February 2007, 21:03
Doc, what did you put under the z-rollers in place of drawing M1-20-220-T ? Or, did you put a smaller center hole through that part? I am still unsure about the seal of that bearing rubbing on the support structure.... (My only experience with ready-made wheels is the size2 BWC and there the seal is not recessed)

DocTanner
Sat 10 February 2007, 02:56
Gerald,
The eccentric bushing itself acts as the spacer.
I placed the hex-headed part of the bushing against the spider plate.

DocTanner

Gerald_D
Sat 10 February 2007, 04:17
That's lucky, and neat, if it leaves enough space for the rack and gas spring.

Does the "Superior" seal sit a bit recessed away from the steel faces?

DocTanner
Sat 10 February 2007, 15:49
Gerald,
You are correct the seal appears flush.
The bushing is slightly beveled so the seal doesn't contact.
The hexhead is approx 3/8" thick. The rack and gas spring have sufficient space.


DocTanner

DocTanner
Sun 11 February 2007, 04:31
I went and rechecked this morning.
The seal is recessed.
Sorry for the confusion.
DocTanner

Gerald_D
Sun 11 February 2007, 22:06
The recessed seal makes everything clear and easy. Thanks

Edmond Duncan Kevin Enslin
Mon 26 February 2007, 01:08
Hi Gerald
Is there a source in South Africa for the V wheels and how much do they cost.

Thanks Edmond

Gerald_D
Mon 26 February 2007, 01:21
If you research via the Bishop Wisecarver or Hepco websites you discover they are locally represented by Star Hydraulics (or is it Pneumatics) they last spoke of around R700 ($90)per wheel, and they didn't always have stock.

Gerald_D
Wed 28 February 2007, 22:12
RS Components www.rssouthafrica.com (http://www.rssouthafrica.com), Stock No. 259-0117, R372 each for 12 or more. Eccentric bush (259-0151) R64 each. (R372 = $51)