Liftrod Compression Spring

[CHIP300]

I'm rebuilding liftrods where I work. Changing out one at a time..cleaning and rebuilding them. I'm curious what others are using for compression spring. OEM?..Zot conversion?..PPP? I've also been coming across that someone has been cutting the bumpers at the end of the spring rod in half. The only purpose I see in that is making the spring rod straight with its wear bushing..but by doing that makes too much tension on the ball toward the ball wheel and causes the ball to get "air" and landing on the return track. I'm trying to get all these to have the smoothest transfer possible. Any input on this would be great.

Thanks,
Chip

[Kanga (James)]

The original spring will do the trick if:

1. The ball is riding the center of the ball wheel.
2. There is good and sufficient kicker material.
3. The lift rods aren't set so high that the lift rods are still contacting the ball too late in elevation (causes ball launching).
4. There aren't excessively worn parts.

The fact that the ball is getting air is proof that the spring is sufficient for this application.

There was a recent thread on lift rods that my be of some help for your re-building job.

http://www.bowltech.com/forums/showthread.php?49214-Centering-lift-rod

[Mechanick]

I try to stay away from any of the setups that puts more pressure on the lift rod through the spring rod. Reason being is that you are increasing the chance of the rod breaking at the top elbow....mainly the one on the short rod.


With a six foot of traction material on my slowed down ball wheels, there is no need for more pressure on the spring rod. And they run without the need of the helper springs from the elevator to the lift rod.....I do admit that at times the helper springs do get used. I have one dangleing on each elevator. Usually if one of the night people are having yoyos on a particular lane, then they will hook it on and mark it down. When I take note of their need to put the spring on, or I notice one while walking the aisle, I check out the lift rods....99% of the time it is because the wheel has run low on tape. Re-tape and take the spring off.

I usually check the wheels at the beginning and end of the season to make sure that they each have a pretty good 6' peice of traction material. Most go through the full season or even full year with needing a 1-3 foot peice added onto what is left (the more centered the lift rods are to the wheel, the longer the traction material will last). Some need a full peice. Im using the cork gasket with self adhesive backing. This practise for me has lead to a major reduction in yoyos and spinners. I swear that they are almost non existent.....and it don't matter how much oil I put on the lane. My house shot is 25ml- it is a little on the oily side, but I need it that way because we have 2 shifts of leagues nightly. And all the balls go up the rods, even the old and heavy balls, or heavy plastic balls, etc....their is no bias, they all go up.

[Popeye]

I'm rebuilding liftrods where I work. Changing out one at a time..cleaning and rebuilding them. I'm curious what others are using for compression spring. OEM?..Zot conversion?..PPP? I've also been coming across that someone has been cutting the bumpers at the end of the spring rod in half. The only purpose I see in that is making the spring rod straight with its wear bushing..but by doing that makes too much tension on the ball toward the ball wheel and causes the ball to get "air" and landing on the return track. I'm trying to get all these to have the smoothest transfer possible. Any input on this would be great.

Thanks,
Chip

The only time I cut the bumpers in half is on the rare occasion I need more snap at the top of the lift rods tho get the ball to hop over. On these the return travel of the spring and the lift rods is not sufficient so I cut the bumper in half.

[SoCalTom]

The only time I cut the bumpers in half is on the rare occasion I need more snap at the top of the lift rods tho get the ball to hop over. On these the return travel of the spring and the lift rods is not sufficient so I cut the bumper in half.

If you need a little extra "zing" from your lift rods and instead of cutting the rubber bumpers, try this.....



It's a scrap bushing and washer on the spring rod.

The other suggestion would to make certain that your lift rods are proper aligned with the ball wheel. The ball wheel should be dead center between the lift rods. In this manner, the width of the ball wheel grabs the center of the ball, and returns the ball smoothly and quickly. It also reduces the chance of the ball becoming airborne and striking the cross conveyor pulley.

[RipOwens]

Some of the newer one piece urethane bumpers are longer than the original 2 rubber bumpers together and trimming them might be necessary to get proper adj. Please understand longer or shorter bumpers, adj rod in or out does not change the spring tension. It is the spring and size of the bowling ball that determines tension,

[Popeye]

Tom, I would be very careful putting a spacer in there. If you bottom out the spring you can cause too much pressure on the lift rods and they will break like Mechanick talked about. The reason I cut the spacer is that I need more movement, sometimes, not pressure in the spring rods.

[Steve Stafford (JBEES)]

I use 1/2 inch washers to shim the compression spring as I can add or remove washers as needed to control pressure or prevent coil binding.

On another note...added spring tension is not a guarantee that a bowling ball will go up the lift rods. What you need to get is an increase in friction which pressure does not always accomplish. This is why kickers were "invented" many years ago...to increase friction between the ball wheel and the bowling ball.

[CHIP300]

Thanks for all the info guys! I'm trying to convert back the the oem compression spring and trying out the springs from ppp and trying to get better belting material to use as kickers.

Chip

[joeshlep]

be careful with the zot setup. someone might over adjust them and the spring will bottom out and bust the liftrods. centering the rods is always best

[Lonnie_Mitchell]

Keep in mind Chip, there are also several manufacturers of these spring rods and many are different lengths from others. For instance, there is a round end spring rod, a square end and a hex shaped end and all three are different lengths. Originally, Brunswick would show in the book using two of the black rubber bumpers. The longer single bumper was to replace the need for two shorter ones. Now comes different length spring rods and the house only has the double bumpers and can only fit a single nut on the spring rod after adjustment. So what do you do? Cut the bumper in half!
Adjusting the spring rod in or out does not create more less pressure on the ball as the compression strength is constant and the same on the ball. The only way to create more pressure is to add spacers or washers at the head of the spring rod as Steve mentioned and as in Tom's photo.
Be very, very careful about adding these spacers and washers as this can and will lead to pre-mature cracks and breaks in the support bracket as well as the spring rod bushing could bust through the hole of the aluminum support.

[Pinsetterbetter]

If you are looking to add more spring pressure, you can do it without adding shims or washers. Use the factory spring and then slip a large outer spring from the moving deck control cable over it and run them both. It will give you all the pressure you need!! I have been doing this for over 15 years and have never had a problem with breaking lift rods.