Author Topic: Loose threads in MZX frames  (Read 1797 times)

Offline sqslabs

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Loose threads in MZX frames
« on: October 03, 2014, 03:34:08 PM »
I just got a few used MZX frames which were shipped disassembled, and on a bunch of them the inner threads (looks like a standard nut) have come loose inside the roller.  Any tricks to getting these things back together once this has happened?
Brett
Squeegee Science
Fort Lauderdale, FL


Offline Zelko-4-EVA

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Re: Loose threads in MZX frames
« Reply #1 on: October 03, 2014, 08:46:32 PM »
shake the nut to the side it came loose from and use a pencil to move it into position,  carefully thread the bolt in.

it might work...

Offline sqslabs

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Re: Loose threads in MZX frames
« Reply #2 on: October 03, 2014, 10:41:08 PM »
Will give it a shot, thanks!
Brett
Squeegee Science
Fort Lauderdale, FL

Offline jsheridan

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Re: Loose threads in MZX frames
« Reply #3 on: October 03, 2014, 11:34:40 PM »
Wow are those old.. that design went out sometime in the mid 90's. If you paid more than 10 bucks each.. sorry bro .. shrug..

Oh yeah.. don't use them in a dip tank as they will leak.
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Offline sqslabs

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Re: Loose threads in MZX frames
« Reply #4 on: October 04, 2014, 06:50:03 AM »
Wow are those old.. that design went out sometime in the mid 90's. If you paid more than 10 bucks each.. sorry bro .. shrug..

Oh yeah.. don't use them in a dip tank as they will leak.
Really?  They aren't in bad shape at all, and there's three different types in the batch (blue powdercoat, blue anodized, silver), each of which have a few rollers with the loose threads. Is there any way besides the coating to tell how old they are?

And yeah, I definitely paid more than 10 bucks each. :-
Brett
Squeegee Science
Fort Lauderdale, FL

Offline jsheridan

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Re: Loose threads in MZX frames
« Reply #5 on: October 04, 2014, 01:19:35 PM »
The tube and locking channel have basically stayed the same over the years with some changes made to improve rigidity. It's the ends caps of the tubes and the corner pieces that have changed. They did paint them blue at one time, but all that did was chip off over time. they still make the M3 tubes in blue while the mzx are natural.

Just by looking at a frame is hard to tell it's age, you have to take it apart and look at the end cap.

The first design had nylon end caps and those were a train wreck. had to start somewhere.

With this style you have, the tube end cap is made from an aluminum alloy casting with a recess to trap the nut from spinning inside the tube. This end cap had the nut glued in place, then using epoxy the end cap was basically glued in place by hand. They stopped using that for the problem you have now along with the epoxy would give way and you could remove the end cap.
Like was said, you can use a pencil to re-trap the nut and then make sure to use some Copper Anti-Seize compound on the end of your bolt. If you don't, you ran the chance of corrosion buildup from reclaim, and trying to loosen the nut, would fracture the back of the plug and the bolt and nut would just spin.. dead tube I called it and I had many back in the day.

After the nut problem, they machined the end caps to be internally threaded with a longer bolt. Solved a ton of problems however it made a new one. When a stainless steel bolt is threaded into an aluminum alloy and placed under torque, 55 f lb, and then placed in a salt solution (reclaim powder is a sodium product) oxidation caused corrosion and a metallurgical bond of sorts seized them together.. more broken end caps.

The addition of copper based anti seize, new cast and machined corners to accept a shaped plastic washer disc to seal out the water solved this, but required a check up every so often and the discs would crush and leak water into the tubes.

around this time is when dip tanks were becoming all the rage and suddenly, all those old frames that had 'mechanical' problems, brought to the forefront the leaking issues. There was also the problem of bowing under tension. There was always some bowing in the long tubes, the M3s had stiffening rods in them and people would buy the cheaper MZX frames to use on their autos, tension them to 40n and warp the snot out of them.

The fix to that is what we have now. A solid cast and machine threaded end cap with a black bolt with anti seize baked on. The corner was re-shaped with a 3 degree angle so when you lock the bolts, the tube was forced outward to aid in the bowing all pressed into the tube.

no more leaks, no more seized bolts and the bowing is minimal.

be it 25 years old or bought brand new last week, you still have a better product than a static frame.

Get those nuts in place, use some good lube, put a polypropelene washer behind the bolt with a washer and torque to 35 ft lb. be cautious for leaks in the dip.

hit up Shur Loc for some mesh panels
« Last Edit: October 04, 2014, 01:31:56 PM by jsheridan »
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Offline sqslabs

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Re: Loose threads in MZX frames
« Reply #6 on: October 04, 2014, 06:26:35 PM »
The tube and locking channel have basically stayed the same over the years with some changes made to improve rigidity. It's the ends caps of the tubes and the corner pieces that have changed. They did paint them blue at one time, but all that did was chip off over time. they still make the M3 tubes in blue while the mzx are natural.

Just by looking at a frame is hard to tell it's age, you have to take it apart and look at the end cap.

The first design had nylon end caps and those were a train wreck. had to start somewhere.

With this style you have, the tube end cap is made from an aluminum alloy casting with a recess to trap the nut from spinning inside the tube. This end cap had the nut glued in place, then using epoxy the end cap was basically glued in place by hand. They stopped using that for the problem you have now along with the epoxy would give way and you could remove the end cap.
Like was said, you can use a pencil to re-trap the nut and then make sure to use some Copper Anti-Seize compound on the end of your bolt. If you don't, you ran the chance of corrosion buildup from reclaim, and trying to loosen the nut, would fracture the back of the plug and the bolt and nut would just spin.. dead tube I called it and I had many back in the day.

After the nut problem, they machined the end caps to be internally threaded with a longer bolt. Solved a ton of problems however it made a new one. When a stainless steel bolt is threaded into an aluminum alloy and placed under torque, 55 f lb, and then placed in a salt solution (reclaim powder is a sodium product) oxidation caused corrosion and a metallurgical bond of sorts seized them together.. more broken end caps.

The addition of copper based anti seize, new cast and machined corners to accept a shaped plastic washer disc to seal out the water solved this, but required a check up every so often and the discs would crush and leak water into the tubes.

around this time is when dip tanks were becoming all the rage and suddenly, all those old frames that had 'mechanical' problems, brought to the forefront the leaking issues. There was also the problem of bowing under tension. There was always some bowing in the long tubes, the M3s had stiffening rods in them and people would buy the cheaper MZX frames to use on their autos, tension them to 40n and warp the snot out of them.

The fix to that is what we have now. A solid cast and machine threaded end cap with a black bolt with anti seize baked on. The corner was re-shaped with a 3 degree angle so when you lock the bolts, the tube was forced outward to aid in the bowing all pressed into the tube.

no more leaks, no more seized bolts and the bowing is minimal.

be it 25 years old or bought brand new last week, you still have a better product than a static frame.

Get those nuts in place, use some good lube, put a polypropelene washer behind the bolt with a washer and torque to 35 ft lb. be cautious for leaks in the dip.

hit up Shur Loc for some mesh panels

Rad, thanks for the breakdown man.  It is greatly appreciated.

One last question... So are MZX frames (four roller) not recommended for use with automatics altogether?  I just assumed the difference was in the max tension, but since I'm running S-Mesh, figured I could get away with them.  I currently have M3's in production and dig them but figured the extra cost (and weight) was unnecessary while running lower tension mesh. Thoughts?
Brett
Squeegee Science
Fort Lauderdale, FL

Offline Gilligan

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Re: Loose threads in MZX frames
« Reply #7 on: October 04, 2014, 06:48:40 PM »
John is the expert but I know of many ppl that use them for the exact same reasons you state, shouldn't be an issue.

Offline sqslabs

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Re: Loose threads in MZX frames
« Reply #8 on: October 04, 2014, 07:57:50 PM »
John is the expert but I know of many ppl that use them for the exact same reasons you state, shouldn't be an issue.

:thumbsup:
Brett
Squeegee Science
Fort Lauderdale, FL

Offline jsheridan

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Re: Loose threads in MZX frames
« Reply #9 on: October 05, 2014, 12:14:53 PM »
The MZX line of frames is designed for the manual user but due to cost shops use them on the autos and they work just fine.

The 18x20 frames can handle up to 50n while the 23x31 frames have a max suggested tension load of 35n and will work perfectly with S mesh and threads that work well under the 35n load.

If you want to go into the 40-60n range, then you need the M3 frames as they have a larger diameter tube and include the internal ribbing for rigidity.

I highly recommend putting your base white screens in the M3 with newman 160n mesh and tension to 50n. use a hard flood, steep squeegee and fast stroke to clear the ink and It will open your eyes to a world of printing you never thought possible.
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