Shirogorov Bearing Balls Diameter?

Thin-Slice said:
Noticed that its not exactly 1.5 mm but rather 1.588mm same as alphaknifesupply which is much much cheaper of course slightly lesser grade but as recommended above G10 is more than sufficient. Might just get those 27 for 100ct as opposed to $1 a piece
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What did you end up doing? I have a 95 and when I disassembled it it has a bearing missing on either side.
 
A garage who does brakes in your area should be able to measure the ball for you. Any machine shop wpuld be a plus using a micrometer which would be more accurate then a dial caliper.
 
I ordered some grade 5 ceramics. At 1.588 mm as someone who said in the thread. We wish find out here in a few days. Thanks
 
Ha, ha, ha
Every time I scan by the title of this thread in the list I keep thinking it is asking about the size of the equipment on a bear.
 
Thin-Slice said:
(Si3N4) (1.5mm 0.0591") Ceramic Silicon Nitride Bearings Ball G5
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Hi, great post! I am now in a similar situation, I disassembled my Shirogorov F95T SLRB and one got away...It works fine but I just know its not complete. Any advise/update on your experience?

Thanks,

S
 
I talked to shiro at blade about ceramic bearings. Their bearings are stainless. If you choose 52100, keep them oiled.

They do not use ceramic due to the tolerances. Ceramic bearings tolerances from one to the next isn’t as tight as what they prefer. Per Sergei, this could result in faster than normal wear on the track and more dimpling of the track with side to side pressure. Just FYI. That said, a buddy changes his out with no problems at all. I have read that shiro makes their own bearings in order to achieve the consistency that they desire but I did not confirm that.
 
SVTFreak said:
I talked to shiro at blade about ceramic bearings. Their bearings are stainless. If you choose 52100, keep them oiled.

They do not use ceramic due to the tolerances. Ceramic bearings tolerances from one to the next isn’t as tight as what they prefer. Per Sergei, this could result in faster than normal wear on the track and more dimpling of the track with side to side pressure. Just FYI. That said, a buddy changes his out with no problems at all. I have read that shiro makes their own bearings in order to achieve the consistency that they desire but I did not confirm that.
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Thanks, very helpful. And the size for the SLRB is 1.5?

S
 
1.588mm=0.0625in= 1/16 of an inch
1.5mm=0.059055in
I don't think the two sizes are interchangeable. One is imperial and one is metric. Being it is Russian, I would think it is a metric ball, but, I really don't know.
 
What the Shirogorov representative sais on another forum in the Shirogorov facts list
Bearing balls are sourced from an external supplier. Everything else we make in house from raw materials.
Our bearing balls come with a standard 1.5mm diameter regardless of the model.
Roller bearings are bought as rods, which we then cut at the workshop
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I don't think I can link them here. But bocobearings.com sells 1.5MM-C SI3N4 BALL GRADE 3. This is going to be the absolute highest quality (smoothness, roundness) bearing available for this knife. Grade 3 is the best grade in the world of bearings(there is no 1 or 2 grades.).
I'm sure most people will find them to be cost prohibited vs grade 5 ($12 for 100 G5 vs $60.72 for 44(2 extra)G3.). But....there are alot of people that say..."you paid $1000 for the knife, spend the $150+ for a screw driver!" So I thought I'd share this.
There is likely no way shiro's bearing are close to grade 3. I don't think metal bearings are able to meet that spec. Grade 5 was the best I could find for metal bearings. That's on Amazon, with no way to know if they are really grade 5. Boco bearings goes to grade 10.
I would wager Shiro's bearings are at best grade 10. If you use the press on the blade technique to loosen the pivot. There are likely flat spots on the oem metal bearings(mine do). I learned the squeeze the knife method (putting pressure on the blade towards the pivot) to help loosen the pivot. Anyways, I'm going to try out a set of these grade 3 ceramic bearings.

If you go the ceramic bearings route, do not use the press on blade method to loosen the pivot. You will put permanent dents in the blade and washers. This will be felt in the action forever.... Also, when tightening with ceramic bearings. Go for loose and tighten with your finger nail until no blade play. If you over tighten, it will make dents in the blade and metal washers. Those things are the drawbacks of ceramic bearings. It's the roundest and lowest friction surface you can get. It will give you the best action your Shiro is capable of. But they can cause permanent damage to the knife if care is not taken. This is 100% the reason they use metal vs ceramic. Better to replace metal bearings when damaged vs permanently damaging the knife.

Is grade 3 vs grade 10 or grade 25 noticeable in action? Who knows... I'm going to give them a try because they have them 35% off right now(black friday, $39 vs $60). At $60.... It would be harder for me personally to pay for... If they truly make my f3ns smoother. Then I may buy another set for my f95t....
Polishing the bearings tracks on the blade and washers with 14k-25k diamond paste and a fine pointed felt tip would likely make a larger difference.
 
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Thanks for that info. Would this impact the Quantum as much? It has stainless bearing race inserts. I'm not sure if those are less likely to be dented by the ceramic than the titanium bearing races in other models.
 
RollTide3 said:
Thanks for that info. Would this impact the Quantum as much? It has stainless bearing race inserts. I'm not sure if those are less likely to be dented by the ceramic than the titanium bearing races in other models.
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The F3ns and F95 both use stainless steel washers vs titanium. The Hation zero I have uses TI races via the scale though.

But, to answer your question. It does go for the quantum as well. If it would dent M390(which is the most important part, washers/races are replaceable), it'll definitely dent hardened steel braces. Ceramic is at 95-96hrc. M390 is around 60-61hrc, the hardered metal washers maybe at 60 hrc.
The oem stainless steel bearings maybe 54-56hrc probably. Most are in the mid-high 40's. Especially the cheap metal ones on Amazon.

Something you can do that helps me with reassembly is put a little thin line or smallish dot at the top of both pivot screws(12 o clock) with permanent marker when assembled(it will wipe off easy, so take to not). When reassembling, turn the main pivot so the line is at top again(12 o clock). When tightening the screw down, turn until it matches that opposite side again(both at 12 o clock). Then you know you didn't over tighten and that the pivot is tightened exactly where it was before disassembly. It's pretty hard to screw up the marker method. Unless your trying to hurry. When messing with $1k+ knives, you shouldnt be hurrying.
The marker comes off with alcohol normally pretty easy. If not after a day it'll wear off. I guess I should have put that in above, but I forgot and that post was getting pretty long.

Most knives come with ceramic bearings now a days. So I use the marker method now when retightening all of them. Pretty much always... For shiro's, normally a thumb nail will work. Max tightness with a thumb nail is normally just right after where blade play stops. Unless you have ridiculously strong or just thin thumb nails.
 
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