350 torquing

Hi Guys,......I have a little experience to share on the benefits of these thrust bearings.

As I need to keep my staff and mowers going all day every day I found that installing these in replacement ofthe greased steel washers atop and bottom of the shafts retaining the castor wheels on mowing decks, reduced the need to grease, reduced the instance of failure of the retaining "C" clip and reduced wear of the washers completely. Needless to say these mowing decks take a hammering all day every day. The directional shock from the wheel up the shaft, combined with the lateral movement of the castor wheels is a very violent as you bounce across the ground. These thrust bearings are just the bees knees and have virtually eliminated downtime due to this area of the mowing deck failing.

I would agree that installing a thrust washer system behind the spring makes sense, as that spring untwists it has to go somewhere. I recently pulled a packing washer out of a gun that had big "bite" marks from the roughly finished spring termination, and accounted for the "twitch" when fired.  I had followed conventional thought and dressed and polished it to mirror finish and reinstalled it with good results. However if I had to repeat the job again I would install the thrust bearings now.

Good discussion guys,.........I enjoyed it very much.

regards Adam

[Gene_SC]

I really don't need to reasearch bearings Rich. I was applying an my experiences with thrust bearing on truck drive train components. I have worked very close with Eaton, Rockwell and Spicer corp on bearing and metal failure for many of my years. Maybe the relative difference in the mechanics are no where near air guns..

Like I said my opinion was based on that industry. Fatigue and hardness failures through applications. And I do think these posts and replies are great stuff for our members. We all can gain experience and knowledge from one another. Thats what it is all  about...

Gene

I agree, definitely makes for good reading and information.  Like Gene, I had origianlly thought about the shock factor before getting one of Rich's needle bearing top hats but decided to give it a whirl anyway.  I am really pleased with the results overall.
Someone brought up another point about adding the bearing behind the spring.  With the bearing factor in mind, Do you guys think that there would be any apprecialble benefit to having a bearing at both ends of the spring? or maybe just overkill.

[Gene_SC]

The whole concept I think here is to keep spring from twisting. I would think if Rich is correct about the impact factor that one end would be sufficient. Myself would  not use bearings. A well polished end with a grade eight polished washer would probably do the trick, if proper lubricant is use between them.

Guess we would not have SUV's instead of station wagons, if someone had not of thought of the concept either..

Gene

[CharlieDaTuna]

I really don't like getting into controversial subjects but.... the idea of using needle thrust bearings has been around for many years and the topic comes and goes every once in awhile and don't last long. I have tried them in different combonations a number of years ago and came to the same conclusion that most of the pro's did in the past. Very few if any of the pro tuners ever use them except in special applications.

 Regardless of what some might say, there is a tremendous amount of impact when the piston slams home (and it's steel against steel) and if you think about it, and what it does, and the relationship it has to the double recoil of the springer and scopes then I think you would agree. Of course there will be some that will disagree also.

Years ago prior to his passing away, and when James Kitching and I were working together, I had discussed the idea of thrust bearings with him. It was one of the few times that he had said to me "get that out of your head. It's a waste of time and your customers money and can cost you in the long run". He would always say to me "get it out of your head"  if I would start on a no-no. Later I would see for myself  the damage that a thrust bearing can cause when it lets go, and personally I would never put one in any of my customers gun. And definitely not in my own guns.

 If it were that advantageous,  then the manufactures would use them , especially in the mid to upper class guns if it were that beneficial. But they don't and for good reason, and it would be very inexpensive for them to do it at the time of manufacture.

When the gun is cocked, the spring itself does not twist much anyhow and how much depends on the construction of the spring. And if you use a Stainless Steel washer as a thrust washer, you will accomplish the same results and possibly even better especially if you are using a tophat as you have three points for rotation at the bottom and at least one at the top. What is important of course is eliminating as mush resistance as possible, especially when it "unwinds". By smoothing the spring ends and removing the grinding marks (and they don't necessarily need to be polished if the proper lube is used) and even more importantly removing the sharp edges both on the inside as well as the outside edges at the cut off you will remove a great deal of resistance. And one more thing that is important. When thrust bearings are used in an application, the outer surfaces of the races "or washers" that the needle bearing sets on in most cases sets on machined flat surface. The surface in the bottom of the piston in springers is not a machined surface for the bottom race to be seated on nor is the spring end if it sets on the opposite race.

Bottom line....in my opinion.... use a thrust bearing if you like, but myself, having tuned literally hundreds and hundreds of guns through out the years, I see little or no real advantage to using them and I've never had a customer complaint about torque. If everything is done correctly, there is no reason too. I don't use them and as I said previously and  I don't know of any tuner that has a few years experience behind them uses them or any other pro-tuner that uses them as part of a normal tune.

Well that was pretty definitive Bob............

I must say I would still like to try it,...........just for an experiment. And with the added benefit of not being a tuner for anyone else's Airguns but myself I can afford to take the loss.

Thanks for your attempt to make me see the error of my ways, You have, but I suppose I am recalcitrant. And yes I am working on a special aplication project.

Regards
Adam.

I will have to admit I dont tune the chinese airgun well not many

I would say 200 or so, 90% of my of my work is with American made or the upper end imports (not Chinese) compared to European the Chinese quality is just not there and to take a 100$ gun then tune it for 150$ never did make any since, Except for the most extreme hobbyist, and it seems that’s what’s been going on in the Chinese airgun world
 (Taking the Chinese airgun to the extreme) not just stopping at 99% but going all the way. And some times exceeding 100 percent !!!! WOW  

Because of this over the top commitment by the Chinese airgun hobbyist I have seen many many awesome over the top springers.

You don’t need special applications to try something new a bearing will always be better then a washer to reduce friction. If you have an idea run with it.

Here is the tophat I built for my sons Legacy it shoots just under 500 FPS we detuned this gun for local competition it is  sweet and smooth.

This gun has over 2 years on it with 1000s of 177 pellets through it,

with the bearing the cocking is much smoother and the shots are quieter and smoother as well  



I have always been amazed at what airgun hobbyists have come up with and more then not extremely impressed with the creative ingenuity most have shown.

It seems there is a lot of knock downs and it wont work say-ers on the forums theses days where there used to be a bunch of pusher uppers with complements and encouragement in the hobby forum world.

I guess for some there is just too much at stake and the hobby has become a high stakes financial endeavor and that for the most part that will take the fun out of it.

I say

Gentlemen start your engines and put your ideas forth take this hobby to the extremes bust through the outermost boundaries ignore the naysayer but remember this is your hobby so relax and enjoy

Be Safe show safe teach safe and allow others to have fun

Ratite
The Airgunsmith    

[CharlieDaTuna]

Like I said, if you are inclined to use a needle bearing thrust, go for it. I’m certainly not condemning it, just saying I myself wouldn't use it as I don't see any real improvement over it in the way that I do things. And I've also seen the damage it “can” cause if a cage lets go. And I’m certainly not saying that it is going to happen if you use it. Just that it’s possible.

As everyone knows, or anyone that has been around for the last 5-7 years, I started with the Chinese guns and eventually would up doing just about all the springer’s from the bottom to the top of the line out there. However, the Chinese guns I see very little of any longer. Where in the very early years the Chinese market made up about 95% of my business, it is now probably less than 15% of it. I get few of them in any longer and those are the B-26’s, the B-30’s and the B-40’s. They were terrible and a real challenge to work on and make into something that was good. But as Kitching and Collins told me a long time ago… if you have the patience and the ability and can successfully learn how to make and convert these Chinese guns into winners, then you'll be good with any springer. Well I think I did that as do several hundreds of customers over the years.

And Ratite is right when he says that there are a lot of Nay-Sayers out there and many people that discourage or knock others for their ideas. I hate to see that and at the same time, I don't like to see people discouraged to a point that they don't post their opinions or voice/present their logic regarding their ideas. I’m certainly one to voice my opinion and the logic behind it and always will, but when I voice my opinion, it is based on not only my many years of past experience but also of others with experiences and logic that are much wiser and with more experience than I.  After all, I find that you can be in this business for ten years and still not know it all.