Any idea on how to fix a broken drop weight tensioner lever?

danwang

New User
I bought an Alpha Pioneer III last night. When I looked at it today I realized I missed seeing that the rod is broken from the base (don't ask me why).
I wonder if JB Weld is strong enough to fix it. Or, must I find a welder?

Here is the link for the picture:
Broken tensioner rod

Thanks very much in advance!
Daniel
 

loosegroove

Hall of Fame
The rod should be held in place by an allen screw underneath, no? So loosen the allen screw and try to finagle the remnant of the rod out. Worse case scenario is you'll have to drill into the rod and tap a screw into there so you have something by which to pull it out. And then you can just get a new rod.
 

esgee48

Legend
Call Alpha and ask. Or maybe @Wes can chime in. I do not recall there being a screw to hold the bar in place. I thought it was screwed into place so a 'tap-and-pull' will not work. You have to tap the broken piece and insert a special screw that will allow you to screw the broken piece out. That's if my memory is right. I can't remember the details; it's been so long.
 
I bought an Alpha Pioneer III last night. When I looked at it today I realized I missed seeing that the rod is broken from the base (don't ask me why).
I wonder if JB Weld is strong enough to fix it. Or, must I find a welder?

Here is the link for the picture:
Broken tensioner rod

Thanks very much in advance!
Daniel
Sorry to see that your machine is not as expected.
I thought the lever would be solid metal but not.
You can try to use JB Weld Epoxy glue and see if that holds or try welding. I doubt JB weld going to hold the repeated usage for long.
 

danwang

New User
@loosegroove I did look for a screw but found none. I think @esgee48 is right. I hope it's a screw-in and not hammered in. If it's the former, I do have some reverse drill bits for extracting broken screws. If it's the latter, I guess I have to weld it up or call Alpha for the part?

BTW, I found Alpha Racquet Sports in Austin, Texas. Mark Gonzales is the Sale Manager. Is this the right company and person? I emailed them this afternoon regarding getting the manual and nylon frame adaptors. Haven't heard from them yet.
 

dahcovixx

Professional
There should be a slot, move the bar from its resting spot til you see the screw. You need a new bar or your tension could be off. I have one here but gonna keep after seeing this :)

Plus if the bar breaks, the big weight will crack your floor or break your toe!!

Here is a pic of the slot

 

danwang

New User
Sorry to see that your machine is not as expected.
I thought the lever would be solid metal but not.
You can try to use JB Weld Epoxy glue and see if that holds or try welding. I doubt JB weld going to hold the repeated usage for long.
The level is a cast-iron core wrapped in a thin sheet of stainless steel. I say "cast-iron" because of the rust and "crisp" look of the broken area. I think if it were steel or regular iron, it would have bent before it broke off. I am disappointed with the quality of the material and construction of this rod.
I agree with you. I think my best bet, without a replacement, is to weld it up. It will be stronger than tapping out the hole and reinsert the rod. It has already broken once at that place. I am also afraid that rust has migrated further into the rod and weakened it.
 

danwang

New User
There should be a slot, move the bar from its resting spot til you see the screw. You need a new bar or your tension could be off. I have one here but gonna keep after seeing this :)

Plus if the bar breaks, the big weight will crack your floor or break your toe!!

Here is a pic of the slot

Unfortunately, mine is a little different from yours. There is no guiding hole for an Allen key. I wonder if I can expose a hex screw somewhere if I take these discs apart. Here is my picture: broken bar

I am curious. How did you insert the picture? It asks for the URL when I click the "insert image" icon. Putting in the above URL for the shared Amazon photo link doesn't work. Do you have your picture stored on a regular web server with a URL that works with this editor?
 

loosegroove

Hall of Fame
Unfortunately, mine is a little different from yours. There is no guiding hole for an Allen key. I wonder if I can expose a hex screw somewhere if I take these discs apart. Here is my picture: broken bar

I am curious. How did you insert the picture? It asks for the URL when I click the "insert image" icon. Putting in the above URL for the shared Amazon photo link doesn't work. Do you have your picture stored on a regular web server with a URL that works with this editor?
I'm on my phone. I clicked on the pic in your link so it would go fullscreen. Then on that pic I chose "open image in new tab". I then copy and pasted the url from that tab to insert here.

 
Last edited:

danwang

New User
Wow! You all must be living on the West Coast. Or, you will have to be a night owl.

@loosegroove Thank you very much for that cool tip!

@Wes A super nice and helpful video you made just for me! I really appreciate it! I tried to look down the little gap between the black metal and the chrome piece. But it too tight for me to see anything. By the way, your stringer looks pristine. It's amazing! You should publish a demo of your machine and how you take care of it on youtube. You can even make a channel with your knowledge. When I was looking at this machine, I searched high and low for any information. It turned up practically nothing.
 

danwang

New User
I think I would drill and tap both ends and connect them together with threaded rod and loctite.
That's also a great idea, much DIY than welding. I may give it a try if I can't find the part or if it's pricey. I even thought about getting the broken piece out and just sticking the remainder into the hole. But then I will have to somehow recalibrate the scale marks since the bar is now shortened :))
 

danwang

New User
Heck, if you drill it a standard size both ends you might be able to glue a piece of round stock in.
Yup! That's even easier. BTW, I may not need to drill the broken end on the base. In Wes' video, he found that the rod could actually be released from a hidden hex screw. I will find out this weekend when I take everything apart.
 
Alternate:
Remove the broken piece (rod), insert part of the remaining rod. But you may need to re-draw the scale and calibrate to see how far the tension is off.
May be shift by 1 inch, so easy to calculate.
 

danwang

New User
Alternate:
Remove the broken piece (rod), insert part of the remaining rod. But you may need to re-draw the scale and calibrate to see how far the tension is off.
May be shift by 1 inch, so easy to calculate.
I am in the same line of thinking. Do you have a pretty accurate and affordable tension gauge to recommend?
 

danwang

New User
Hey, @Wes . What do you think of a frequency analysis app for string tension measurement? Are they any good? Or, you have a decent affordable one to recommend? I guess I am going to have to need one however I fix the tensioner bar.
 

Wes

Professional
Hey, @Wes . What do you think of a frequency analysis app for string tension measurement? Are they any good? Or, you have a decent affordable one to recommend? I guess I am going to have to need one however I fix the tensioner bar.
This seems like a bit of a loaded question.
Are you...
(a) asking in regards to solving the issue of re-calibrating your Pioneer III after you get it mended, or...
(b) just asking, in general, for the purposes of tracking tension loss?
 

danwang

New User
This seems like a bit of a loaded question.
Are you...
(a) asking in regards to solving the issue of re-calibrating your Pioneer III after you get it mended, or...
(b) just asking, in general, for the purposes of tracking tension loss?
Eh? I wasn't as sophisticated as you think. How about you answer both questions? Now that you brought them up :)
 

danwang

New User
BTW, I have a little bit of good news and a little bit of bad news, regarding Alpha tech support. The good news is Mark finally responded tonight and gave me the link to the Alpha Pioneer Series Manual. The bad news is they have exhausted all their replacement parts 24 years after the last one rolled off the production line, save for some $10 clutch springs.

Now, the turntable is not moving. There are quite a few rusty spots on the paint and chrome surfaces. 11 frame adaptors are missing (hopefully I don't need any of them). And the tensioner rod is broken.

Getting ready to get into full DIY mode... zoom... zoom!!!
 

golden chicken

Hall of Fame
You can literally do the math. The weight weighs X and is placed Y distance from the pivot. The string gripper is a radius Z.

X(Y/Z)= tension being pulled.

In the case of a Gamma dropweight, the weight is 5lbs and the radius of the gripper I believe is 1 inch. So if you mount the weight 10 inches up the lever, you should be pulling 50lbs.
 

frank52

Semi-Pro
Be careful when unscrewing that whole tensioner unit. Try to hold the pieces together. There is a clutch spring inside that is tricky to re-insert.

Glue
I would not trust gluing the beam.
Once you unscrew the allen head tightening screw you could use your glue to glue a little stick to the broken nub. That will be your handle to pull out the broken piece. This may be necessary if the broken bit does not fall out after you have removed the tightening screw. Or, drill a hole in the broken bit and insert a screw into it as a handle.

New Beam
The broken weight beam looks the same as the weight beam on an Eagnas Combo 710. You could contact Eagnas and order "a weight beam for an Eagnas Combo 710". FYI: Don't ask for measurements or ask if this fits your non-Eagnas machine. You will just anger the guy.

Re-use the Old Beam
The best, cheapest, and simplest way is to just pull out the broken bit and reinsert the remaining beam into the hole. Either end could go into the hole. Then screw in the tightening screw. Final step is to install the weight markings in the right place. You can use an inexpensive luggage scale to recalibrate. Your beam is long enough that the broken bit will not be an issue.
 
Last edited:

danwang

New User
You can literally do the math. The weight weighs X and is placed Y distance from the pivot. The string gripper is a radius Z.

X(Y/Z)= tension being pulled.

In the case of a Gamma dropweight, the weight is 5lbs and the radius of the gripper I believe is 1 inch. So if you mount the weight 10 inches up the lever, you should be pulling 50lbs.
The formula looks so simple. I will need to watch a couple of stringing videos to understand the relationship between the string gripper radius and the tension. Thanks.
 

danwang

New User
New Beam
The broken weight beam looks the same as the weight beam on an Eagnas Combo 710. You could contact Eagnas and order "a weight beam for an Eagnas Combo 710". FYI: Don't ask for measurements or ask if this fits your non-Eagnas machine. You will just anger the guy.

Re-use the Old Beam
The best, cheapest, and simplest way is to just pull out the broken bit and reinsert the remaining beam into the hole. Either end could go into the hole. Then screw in the tightening screw. Final step is to install the weight markings in the right place. You can use an inexpensive luggage scale to recalibrate. Your beam is long enough that the broken bit will not be an issue.
Great insights! I think I will try re-using the old beam first. Thanks.

I did get the drum with the broken stud separated from the pivot support and removed the tiny hex screw on the side that held the stud in place. Even after I sprayed a ton of PB Blaster (for three days now) the stud won't come out. I tried to drill and reverse drill it out (with an extraction set) but it didnt't budge. My drill bits weren't sharp enough. I think my best chance to get it out is to find a good drill bit, tap it, and thread a nut in to pull it out. Here is the picture: Broken tension rod
 

Wes

Professional
Great insights! I think I will try re-using the old beam first. Thanks.

I did get the drum with the broken stud separated from the pivot support and removed the tiny hex screw on the side that held the stud in place. Even after I sprayed a ton of PB Blaster (for three days now) the stud won't come out. I tried to drill and reverse drill it out (with an extraction set) but it didnt't budge. My drill bits weren't sharp enough. I think my best chance to get it out is to find a good drill bit, tap it, and thread a nut in to pull it out. Here is the picture: Broken tension rod
Yeah... I kind of had a feeling that it was going to give you some trouble (I didn't want to jinx you).

Based on that photo (post #9 above), it sure looked like that broken piece might be all siezed up (from rust or whatever else).

Even after successfully getting the little set screw loosened/removed - if you had reported back that the stud just fell right out, all nicey-nice, on it's own accord - I would have been pretty surprised.
 

graycrait

Hall of Fame

Kroil is the king of loosening up seized parts. It stinks though.

If you find a way to get a grip on that piece in the weight you might try heating the weight if that is possible, like stick it in the oven. Don't put it in the oven without cleaning solvents off first! Be safe! Or put it in the freezer. Who knows what the different expansion/contraction rates might be between the weight and broken piece? Maybe you could drill another smaller hole through the other side and tap it out, when heated or frozen or at room temp.
 

esgee48

Legend
If the issue is rust, you can try drilling multiple holes into the broken piece and then breaking it out; soaking in white vinegar to convert the rusted iron to acetate ; or both. I do not think oven/freezer will work since the piece is basically steel with a chrome coating. I would use a blow torch, the kind used to brown food. If you try this, try thermal shocking which is heating then quenching in an ice bath. Be careful because you can warp or break the piece. One place I know that could get it out is a machine shop.
 

danwang

New User
Thanks, everyone, for all the ideas. I took it to a friend who's a retired diesel mechanic. He suggested that we first try to weld a wire on it and pull it out. He also has a drill press. We will do it together after work when he can get around to it today or tomorrow. I also thought about heating it up but he doesn't think it will work. Also, it looks like we will have to shave the rod to fit it back into the hole because the remainder is actually larger than the hole and has a flat side where the measurement is. He doesn't think welding the broken pieces together will work that well either.

I never had to try Knoll. WD40 and Pb Blaster have always worked for me. I will get a can ordered just in case this happens again.
 

mark999

Rookie
50/50 mix of ATF (automatic transmission fluid) and acetone is the best penetrating fluid available. just Google it.
 

danwang

New User
Yah. I heard about the use of ATF but never tried since I have enough cans from 3-4 brands. Project Farm has a comparison in which ATF with acetone came out in second place. In first place is Liquid Wrench.
 

Irvin

Talk Tennis Guru
Vegetable oil with five percent acetone works as wells as automatic transmission fluid with five percent acetone. Increasing the acetone content to 10 to 30 percent boosts the mixture's performance.
 

graycrait

Hall of Fame
Project Farm
@danwang, Good thing "she who must be obeyed" is leaving for a couple of weeks. I had never heard of this site before. I can see many "wasted" hours. Thanks!

Now I am in the "rabbit hole" but I have a can of Kroil, can of PB Blaster and Liquid wrench, so probably won't get a can of acetone "yet." Although I have some ATF on the shelf. One other thing I read is patience is key, some work faster than others but most work.


I use both, I've had better results with Kroil. Quote: "A study done by Machinist's Workshop magazine in their April 2007 issue looked at different penetrating oils to see which one did the best job of removing a rusted bolt by measuring the pounds of torque required to loosen the bolt once treated. If the study was scientifically accurate, it turns out a home brew works best! Here's the summary of the test results: Penetrating oil ..... Average load None ...................... 516 pounds WD-40 ................... 238 pounds PB Blaster .............. 214 pounds Liquid Wrench ...... 127 pounds Kano Kroil ............. 106 pounds ATF-Acetone mix....53 pounds"
 
Last edited:

danwang

New User
This machine was bought at $200 price? Asking for a friend.
Yes. According to wes and later my research it would be a good price if you aren't missing any parts (keep an eye on the 13 nylon inner frame adapters). It was not a good deal for me because I didn't notice the tension rod was actually broken, not disconnected, from the base.
 

danwang

New User
@danwang, Good thing "she who must be obeyed" is leaving for a couple of weeks. I had never heard of this site before. I can see many "wasted" hours. Thanks!

Now I am in the "rabbit hole" but I have a can of Kroil, can of PB Blaster and Liquid wrench, so probably won't get a can of acetone "yet." Although I have some ATF on the shelf. One other thing I read is patience is key, some work faster than others but most work.

214 pounds Liquid Wrench ...... 127 pounds Kano Kroil ............. 106 pounds ATF-Acetone mix....53 pounds"
I did waste many hours. I normally wear a Bluetooth earbud and sit in the corner :)
I have plenty of penetrating oils except for Kroil. I also have plenty of ATF and Acetone. I don't like to touch them because both are nasty and hazardous they get on you. But now I know what to do if I run low on my supplies or if all other oils failed.
 

jim e

Legend
That was my first thought. But my "dremel" knockout's tiny rotary head was broken. And the cutting wheel is a bit too big anyway.
If you have a dremel, get a small diamond bur, and just slice a slot in middle, twist it out with screwdriver and be done with it.
 
Top