Will centrifugal forces break JB Weld???

[quexpress]

Hi!
Last fall I have had a set of OEM wheels chromed and am now ready to install new tires.
Normally, if chromed OEM wheels are "off-balance", grinding off the heavy spot (inside the rim, under the tire of course) usually brings the wheel close enough to being well balanced. Weights or Dayna Beads can easily take care of the rest.
One of my wheels was "off-balance" by 2.25 oz. After grinding off the heavy spot, the wheel was now 1.25 oz "off-balance". I didn't like that and decided to JB Weld a strip of 1.25 oz weights inside the rim (under the tire).

I know that JB Weld is very strong:

Tensile Strength:   3960 PSI
Adhesion:               1800 PSI
Flex Strength:       7320 PSI
Tensile Lap Shear: 1040 PSI

However I now wonder if centrifugal force could rip it off the wheel.

Any insight on this?
TIA!

[junior]

depends on the bond factor, if it isnt glued on tight its gonna fly off

[Daniel Meyer]

When you're spinning 'round, things come undone...

I would guess eventually, yes...just due to the hostile environment.

What eventually means is anybody's guess...it may well last till the next ice age...or tomorrow...

[Ricky-D]

Drill and tap some shallow holes there inside the wheel. There's plenty of meat to do this.   Use the bolts to either anchor the JBWeld or to hold the weights themselves.

If you're talking about Valkyrie wheels,,,,, there are hollow areas in the cast spokes that you may be able to utilize to balance the wheel.

I would strongly suggest using a quality dynamic balance machine however, to accomplish the task properly.

***

[Rocketman]

Assuming a rim diameter (distance from center of axle to the weight itself) of 10 inches, an outer tire radius of 13 inches, and a max speed of 140 mph (no one here would ever think of going over the posted speed limit, of course, though, right?), with a weight of 1.25 ounces, using F=mass* (angular accel)^2*radius, that gives a force of ~73 pounds.  I don't know how much area you have, but I do know that JBWeld's actual strength varies dependant on surface prep, age of the epoxy at time of use, and as Daniel pointed out, environmental factors after application.  The 1800 psi is what you need to use, so there's a lot of wiggle room, even if you only have a half inch^2 of application area.

I would still wonder why you wouldn't just put it on the outside as is standard...

[quexpress]

Assuming a rim diameter (distance from center of axle to the weight itself) of 10 inches, an outer tire radius of 13 inches, and a max speed of 140 mph (no one here would ever think of going over the posted speed limit, of course, though, right?), with a weight of 1.25 ounces, using F=mass* (angular accel)^2*radius, that gives a force of ~73 pounds.  I don't know how much area you have, but I do know that JBWeld's actual strength varies dependant on surface prep, age of the epoxy at time of use, and as Daniel pointed out, environmental factors after application.  The 1800 psi is what you need to use, so there's a lot of wiggle room, even if you only have a half inch^2 of application area.

I would still wonder why you wouldn't just put it on the outside as is standard...

An engineering friend calculated that the wheel would exert 91 lbs/PSI. That is very close to your 73 lbs/PSI. I agree with you. At 1800 PSI, there is a lot of wiggle room. They are therefore staying there.

Why wouldn't I just put them on the outside? ... because I don't want ugly wheel weights on a beautiful chromed wheel. I have been using Dyna Beads for the past few years, and will continue with these chromed wheels also.

Thanks for the input. It is very appreciated.

[quexpress]

Drill and tap some shallow holes there inside the wheel. There's plenty of meat to do this.   Use the bolts to either anchor the JBWeld or to hold the weights themselves.

If you're talking about Valkyrie wheels,,,,, there are hollow areas in the cast spokes that you may be able to utilize to balance the wheel.

I would strongly suggest using a quality dynamic balance machine however, to accomplish the task properly.

***

That's an original idea. Never thought of that. I'll wait to see if the JB Weld holds as it should.
Thanks!

[quexpress]

When you're spinning 'round, things come undone...

I would guess eventually, yes...just due to the hostile environment.

What eventually means is anybody's guess...it may well last till the next ice age...or tomorrow...

LOL! Thanks Daniel!

[quexpress]

depends on the bond factor, if it isnt glued on tight its gonna fly off

I agree. Hopefully I didn't screw it up. Time will tell. 

[Daniel Meyer]

When you're spinning 'round, things come undone...

I would guess eventually, yes...just due to the hostile environment.

What eventually means is anybody's guess...it may well last till the next ice age...or tomorrow...

LOL! Thanks Daniel!

Well...ya know...I like to give specific answers when I can LOL!

[Rocketman]

Why wouldn't I just put them on the outside? ... because I don't want ugly wheel weights on a beautiful chromed wheel. I have been using Dyna Beads for the past few years, and will continue with these chromed wheels also.

Thanks for the input. It is very appreciated.

Good reason.  As the numbers say, it should hold for quite a while, probably more toward the ice age end of things (:
Either way, I would suggest a very close inspection of that bond every time you replace the tire.

[Ricky-D]

I think this will be my last on this subject but consider:

A little out of balance wheel can be a good thing.

I say this because nothing is perfect and tires are no exception so, an excellent balanced tire and wheel combination can sometimes be achieved simply be moving the tire around on the wheel to find the "sweet spot".   NO WEIGHTS USED

So the response will be about how painful it would be to have to air the tire up, check the balance, let the air out, break the bead and shift the tire a little bit and start the process again.  Well you don't need to do that!

Who says you have to air up a tire in order to check the balance.  You don't  Oh yeah, it might not be 100% but it will be damn close I assure you. Just be sure the tire is not cockeyed on the wheel which you ought to be able to eyeball good enough.

So now get a piece of chalk and start marking and testing. When you find the best spot, then air up the tire. Maybe adding weight will not be needed.

***

[quexpress]

I think this will be my last on this subject but consider:

A little out of balance wheel can be a good thing.

I say this because nothing is perfect and tires are no exception so, an excellent balanced tire and wheel combination can sometimes be achieved simply be moving the tire around on the wheel to find the "sweet spot".   NO WEIGHTS USED

So the response will be about how painful it would be to have to air the tire up, check the balance, let the air out, break the bead and shift the tire a little bit and start the process again.  Well you don't need to do that!

Who says you have to air up a tire in order to check the balance.  You don't  Oh yeah, it might not be 100% but it will be damn close I assure you. Just be sure the tire is not cockeyed on the wheel which you ought to be able to eyeball good enough.

So now get a piece of chalk and start marking and testing. When you find the best spot, then air up the tire. Maybe adding weight will not be needed.

***

I have been balancing my own wheels for quite a while and can tell without hesitating that you have described most of what I do when balancing them. I ALWAYS look for the best spot and turn the tire when needed.
Thanks!