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Numatx rivet squeezer

StressedOut

Well Known Member
Is anybody using the Numatx compact rivet squeezer? After a lengthy nut plate riveting session with my 7 lb squeezer my shoulder was pretty sore the next day. I've been eyeing the compact squeezer but wanted to get some feedback on it from the community.
 
Numatix

Used mine for all dimpling, excepts the skins and for a ton of riveting. Compact, light and reliable.
Cleveland's Main squeeze is another gem!
Would not tackle a build without either.
Unless my wife OK the "Pop rivet" -15 :)
 
I forgot to ask in my original post about how you adjust the squeeze stroke. In mine it's adjustable by screwing the plunger in and out. I read the manual on the Numatx website and it seems that it's automatic?? It wasn't clear to me.
 
I like mine. Took a bit of finageling to set up, but once you bleed it all... twice... then it's very very good.

you control the air pressure going to the unit which controls how much force is applied. You just have to be mindful of the flat sets that you use, as sometimes you want to use ones that are a bit thicker or thinner depending on rivet length.
 
I recently purchased my Numatx and I have only done the practice kits with it, but I like it. I chose it over a pneumatic squeezer due to the size and that it always squeezes with the same force vs. a pneumatic squeezer only hits it's force at the end of stroke. This way with the Numatx you don't have to adjust the set length for each different length of rivet. In the end I bet you get good at that with the pneumatic squeezer so it probably isn't a huge deal. You also control it with a foot pedal so it might be easier to use in tight spots, as long as you can get your foot to the pedal. There are always trade offs.

Basically you do some trial and error to figure out what pressure you need to squeeze a -3 and -4 rivet then you just always set your regulator to those pressures. A good starting point I was given was 60psi for -3 and 85psi for -4.

I had to bleed it twice (I think using it some in between moved any remaining bubbles around). I clamped my squeezer head to the top of a step ladder to make sure there were no dips in the hydraulic hose while bleeding. Once you have that, you just need to make sure the sets bottom out (you'll see the yoke flex a bit). If it doesn't bottom out you won't get the force you need (same as any squeezer). It does come with two different length rams. So far I have been able to use the short one most of the time. I will probably order one more flat set that is a length in between the two I currently have and that should minimize the number of times I need to swap out the rams.

I also built a small platform out of scrap plywood and 2x2's so the pedal and air/hydraulic intensifier don't move around and I put a handle on it so it is easy to locate. I'll try to post a picture later. I saw the Flyboy guys at Oshkosh had a similar setup.

I didn't go for the hose upgrade since I was already spending more than a pneumatic squeezer. I figured if the regular hose bothered me I can always order it later.

Hope this helps.
Doug
 
I forgot to ask in my original post about how you adjust the squeeze stroke. It wasn't clear to me.

I used thin washers as shims for the dimpling dies or squeezer dies. I removed the shims or added shims for a desirable rivet head. This way I could use the full travel of the squeezer. You can buy a package of thin throwaway washers from McMaster
 
I used thin washers as shims for the dimpling dies or squeezer dies. I removed the shims or added shims for a desirable rivet head. This way I could use the full travel of the squeezer. You can buy a package of thin throwaway washers from McMaster

But you don't need to adjust the squeeze stroke with a Numatx squeezer. The entire stroke has the same force capability vs. a pneumatic squeezer that only has full force at the end of stroke. Small washer worthy changes are not required. If you have a large difference Numatx does send you two different length rams (1/4" difference). This video is useful to see the differences in squeezers https://youtu.be/fxn5aqW7CFs.
 
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I have not had much luck with my Numatx. The first one leaked around the primary piston seal, replaced easily with vendor. The second one just recently started leaking in the same spot as well. Construction does not seem to be the best, thread walls are really thin, etc.

Additionally, I cant seem to get it to put out enough force to properly do a dimple or squeeze a -4 rivet. I've bled it 3 or 4 times, done the ladder trick, had multiple people over to look it over and give their thoughts & help bleed. I basically stopped bothering with it and just use a hand squeezer or the regular pneumatic.
 
You will be laughing and kicking yourself at the same time once you get one.
It is so cool to just push your foot down and get a perfect rivet every time.
I even got a 6" yoke from some guy on Marketplace.
I started this journey With my 1991 RV-6 kit and I understand the squeezer pain.
Bought my Numatx a few years ago and love it. Did I say I LOVE it.
Great tool
Art
 
I have the Numatx, and if I had it to do over again I would get a pneumatic squeezer instead. It's still much better than squeezing everything by hand, but mine has a few problems.

  1. Bleeding. The initial bleeding isn't too bad. As others have mentioned it often takes bleeding twice to get all the air out. Once that is done properly, it works great. My problem is that it works great for about a day. The next day I'll have to turn up the air pressure some more to get it to fully set a rivet. I'll keep doing this for a few weeks before I'm unable to fully set a rivet without exceeding it's maximum rated pressure. At that point I'll need to bleed the system again. --I haven't used it for over a month now because of this. I find that unless I'm planning on >100 rivets in a session, it's just easier to manually squeeze than to mess with bleeding it... yet again.

  2. Alignment. There's some play where the yoke attaches to the squeezer. With little to no pressure applied the squeezer body is perfectly perpendicular to the yoke and the dies are nice and parallel. As pressure is applied, the yoke will shift. This means that the dies will no longer be parallel. So now one must decide if this angle will be applied to the factory or the shop head. If the squeezer body is continued to be held perpendicular to the skin, the result is that one side of a flush rivet will always sit proud while the other side is slightly recessed. To compensate, the squeezer must be angled as pressure is being applied. The goal is to keep the yoke aligned with the skin by purposefully misaligning the squeezer body. --This has taken some practice, but I've gotten pretty good at it. Again, I find that unless if I'm squeezing a bunch of rivets, it's just simpler, faster, and better final results to manually squeeze.

  3. Control. Especially because of the fine control required for issue number 2 above, I find the foot pedal control to be lacking. It's very difficult to "feather". In order to get a good flush rivet I need to apply enough pressure for the squeezer to hold the rivet without squeezing until after I shift it slightly (to compensate for the misalignment mentioned above). --I'm certain I could fix this one by buying a higher quality pedal. However, given the other issues I don't see this tool as being worth investing more money into.

  4. Air leaks. There are minor air leaks in multiple locations. I could likely fix the majority of these (except for the leaks internal to the foot pedal) by disassembling, applying some thread sealant, and replacing a few connections. --I'll likely do this at some point. But for now I just disconnect the air line when I'm not using it.
With all the above being said, I don't hate it. The concept, weight, and the ability to go from one rivet length to another without making adjustments is great. It's just the execution could be better.
 
But you don't need to adjust the squeeze stroke with a Numatx squeezer. The entire stroke has the same force capability vs. a pneumatic squeezer that only has full force at the end of stroke. Small washer worthy changes are not required. If you have a large difference Numatx does send you two different length rams (1/4" difference). This video is useful to see the differences in squeezers https://youtu.be/fxn5aqW7CFs.

That is true but the Numatx is out of my price range so I make due with what I have.
 
Thanks for all the responses. So if I understand it correctly, it takes a set amount of force to properly squeeze a specific diameter rivet to get the desired shop head regardless of the rivet length. You set that force by adjusting the air pressure.

I'll be on the lookout for the issues others have brought up too. Based on the generally positive responses, I've just placed the order for it and should get it next week.
 
Love my Numatx

It all been said already….. but I love mine and wouldn’t trade it for anything. Probably my favorite tool.
 
I bought the Numatx tool with the optional hose and all the yokes before starting my -14A build. I love it and almost look forward to repetitive rivet jobs. They are expensive but you can get most of your money back when you sell it later.
 
I have one of the originals, built by the first Numatx company. Love it. I cant speak for the newer versions, but mine is just fine. I dont use it as much any more--but its still a great tool.
Tom
 
Hey guys I picked up a Numatx and have been tinkering with it. What is the length of piston travel for you guys? Out of the box there was plenty of air I had to bleed out of the lines and air leaks in a few of the air connectors, but I seem to have sorted all of that out. Piston travel doesn't seem like enough though.

Here's my setup FWIW
 

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Piston length

Hey guys I picked up a Numatx and have been tinkering with it. What is the length of piston travel for you guys? Out of the box there was plenty of air I had to bleed out of the lines and air leaks in a few of the air connectors, but I seem to have sorted all of that out. Piston travel doesn't seem like enough though.

Here's my setup FWIW

The Numatx comes with two rams of different length. The longer one will squeeze most rivets, but when a longer rivet is required, the shorter ram is swapped in for the long one. This allows coverage of the range or rivets typically used. The ram is held in place by an Allen screw at the bottom of the center hole. Just unscrew that, and replace with the other ram when required for proper length.

That’s how mine came, and it covers the gamut.
 
Hey guys I picked up a Numatx and have been tinkering with it. What is the length of piston travel for you guys? Out of the box there was plenty of air I had to bleed out of the lines and air leaks in a few of the air connectors, but I seem to have sorted all of that out. Piston travel doesn't seem like enough though.

I'll have to measure the stroke sometime, but what I've done to minimize times I need to change the ram is to buy a couple more flat sets. I've found I need the shorter ram with my dimple dies so for some short rivets I just use a longer flat set to make up the difference of the shorter ram. I think I have three lengths of flat sets right now and that has worked well.
 
Love mine for sure!

Mine didn't come with two rams like Dan N. but I have been able to get the right spacing with washers and/or different thickness in the sets.

Oh...and I had to bleed mine more than twice to get it working correctly. If you find you cannot set those #4 rivets, no matter what PSI you crank it to...bleed it again. And maybe again.
 
Can someone explain to me how you supply air to the foot pedal? There are no instructions at all about an air source. The hose is 1/4" (and the unit did not come with any hose for the air supply; the instructions just show a little pig tail and call it "shop air inlet"). The foot pedal end uses a one-touch fitting. How do you connect that to a compressor? And what psi do you set? There was nothing on the web, nothing in the instructions, and nothing on the Numatx web site.

Any help would be appreciated.
 
Can someone explain to me how you supply air to the foot pedal? There are no instructions at all about an air source. The hose is 1/4" (and the unit did not come with any hose for the air supply; the instructions just show a little pig tail and call it "shop air inlet"). The foot pedal end uses a one-touch fitting. How do you connect that to a compressor? And what psi do you set? There was nothing on the web, nothing in the instructions, and nothing on the Numatx web site.

Any help would be appreciated.

Here’s my setup. Hose came from Home Depot (compressor tank drain hose) and added small regulator at other end.

I have been using 48 psi for 3/32 and 75 psi for 1/8.
 

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Can someone explain to me how you supply air to the foot pedal? There are no instructions at all about an air source. The hose is 1/4" (and the unit did not come with any hose for the air supply; the instructions just show a little pig tail and call it "shop air inlet"). The foot pedal end uses a one-touch fitting. How do you connect that to a compressor? And what psi do you set? There was nothing on the web, nothing in the instructions, and nothing on the Numatx web site.

Any help would be appreciated.

I suggest a small regulator mounted next to the foot pedal (so it can be easily adjusted), with a push on fitting to go from the 1/4 NPT to 1/4 OD poly tube. This can run to the pedal. I used push on fittings and 1/4 poly tube for all the pedal fittings, and on the intensifier. You will need to experiment with a few rivets to get you PSI for a correct set for each diameter. But once you know it will stay the same.

As for the hook up, here is a diagram of the valve function from Nitra (who makes the pedal):

https://cdn.automationdirect.com/static/specs/nitradirectionfootpedal.pdf

And a you tube link for a basic explanation of similar drawings, in case they are unfamiliar:

https://youtu.be/bXXL-0sf8gs

Also the Numatx docs page - probably what you already have?

Hope that helps......
 

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Here’s my setup. Hose came from Home Depot (compressor tank drain hose) and added small regulator at other end.

I have been using 48 psi for 3/32 and 75 psi for 1/8.

So you took the one-touch fitting out of the foot pedal, and installed a standard threaded pneumatic fitting in its place?
 
Yeah, the problem with the Numatx docs is there is ABSOLUTELY NO INFORMATION about the air supply, or how how you connect it, or how you use it. Weird!

Yes, understood. That is where the Nitra document becomes helpful. Essentially there is an air supply line (which should be in the center) and two output lines. One output line pressurizes the squeezer in the open position, and the other in the closed position. The unpressurized line is vented to allow the piston to move. These positions pressurize opposite sides of the piston. I would suggest connecting the air supply (about 50-60 PSI for starters) to the center position. Connect the two intensifier connectors to the outboard ports on the pedal. Then see what happens…. If the squeezer is closed and opens with pedal action, then your intensifier lines are backward - just switch them. If the squeezer is open and closes with pedal action then you are all set and nothing to change. Once the lines are correct you can experiment with PSI to achieve full rivet set for #3 and #4 rivets.

That’s it in a nutshell. The Nitra pedal doc schematics will lead you to the same setup plan, but avoid the trial and error.
 
So you took the one-touch fitting out of the foot pedal, and installed a standard threaded pneumatic fitting in its place?

I don't recall what if any one-touch fittings were pre-installed, but the center hole (mine is marked N) is the inlet air hole, as seen in the pic I posted. It is standard 1/4" NPT.
 
I don't recall what if any one-touch fittings were pre-installed, but the center hole (mine is marked N) is the inlet air hole, as seen in the pic I posted. It is standard 1/4" NPT.

Thanks! I got my from Flyboy Accessories, so it came pre-assembled :)
 
Thanks for the input. I got it all set up and working tonight. Did the whole rear spar of the horizontal stabilizer :) Really slick, and perfect rivets every time.
 
Resurrecting this thread. After a number of months, I finally got around to setting up my squeezer with a base and regulator but ran into a problem. I bought my unit without yolks since I have a full assortment of them already that I use with my pneumatic squeezer. When I tried to fit my yolk to the new squeezer I found then holes were slightly misaligned.

I sent the unit back to the manufacturer and they said their yolks fit perfectly. However, they manufacture their own yolks so it makes sense that theirs would fit.

So a couple of questions:

1. When you bought your unit, did you also order yolks or did you have existing ones?
2. Did anybody else have this problem with their existing yolks not fitting the Numatx squeezer?
 

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No problems with mine. Lines up with all my other yokes easily. All my other yokes are CP214 style, as I think is the case for most but not all. Is it possible that the yokes you have are not the 214 style?
 
I bought them from Cleaveland Tools starting in 2017 and adding as I built. I called them a while ago to confirm they are using the CP-214 standard and they said they were.

I found a manual from Chicago Pneumatics (the CP in CP-214) that had some detailed dimensions for the yolk interface to the body today. I'll do some measurements on my yolks to see if they match.

The pneumatic squeezer I bought from Cleaveland has a ram that is a loose fit that can accommodate some misalignment, but the Numatx design by necessity can't have that slop in it.
 
It is hard to tell anything from the photos. I have an Avery hand and XX Pneumatic, I got an extra pair of pins and one set is a tad larger and much harder to get installed. You might measure the pins to be sure, but it sure sounds like a bad tolerance stack up.

Do you need pin distance numbers from others?
 
Thought I'd share the resolution of this issue with everybody. I had a lot of back and forth with the company in both email and on the phone trying to figure out the reason things were not aligning. They returned my unit back to me after their engineering manager couldn't find a problem. Their yokes fit while mine didn't.

I resigned myself to making some new shear plates that hold the yoke to the body with the proper alignment. The plates were removed and I thought let me try to reassemble them with my yokes to align things. Well, that did the trick. With the shear plates fastened to my yoke I was able to align the plate holes with the body holes. I tested all of my yokes and they now fit fine.

The only thing I didn't like is they use actual screws to attach the shear plates to the squeezer body instead of smooth shank bolts. Seems like a very bad idea. I'll see if an AN bolt of proper length will work here.
 
Thought I'd share the resolution of this issue with everybody. I had a lot of back and forth with the company in both email and on the phone trying to figure out the reason things were not aligning. They returned my unit back to me after their engineering manager couldn't find a problem. Their yokes fit while mine didn't.

I resigned myself to making some new shear plates that hold the yoke to the body with the proper alignment. The plates were removed and I thought let me try to reassemble them with my yokes to align things. Well, that did the trick. With the shear plates fastened to my yoke I was able to align the plate holes with the body holes. I tested all of my yokes and they now fit fine.

The only thing I didn't like is they use actual screws to attach the shear plates to the squeezer body instead of smooth shank bolts. Seems like a very bad idea. I'll see if an AN bolt of proper length will work here.

Glad to hear it worked out for you. Thanks for sharing the solution.
 
Resurrecting this thread... again.

I've put 6x 60cc charges through my Numatix (which came with fluid already in it) and I just can't seem to get it to fully squeeze -4 rivets.

While bleeding, I've got the C-squeezer on a shelf near the ceiling of my garage. The hydraulic line is almost vertical. I must be doing something wrong. Any hints are greatly appreciated.
 
Resurrecting this thread... again.

I've put 6x 60cc charges through my Numatix (which came with fluid already in it) and I just can't seem to get it to fully squeeze -4 rivets.

While bleeding, I've got the C-squeezer on a shelf near the ceiling of my garage. The hydraulic line is almost vertical. I must be doing something wrong. Any hints are greatly appreciated.

Double check that ram you have installed is the correct length for the rivets you are squeezing. It comes with a short and long ram, which are attached to the drive piston with an allen screw at the bottom of the hole in the ram (where your die stem mounts). The piston (and thus ram) has a limit to its length of travel, and if you happen to be squeezing a short rivet with the short ram, it will not fully compress…. Worth a check, as it would lead to incomplete set even if fully bled.
 
I dont know about the newer version, since I have one of the first 'real Numatx' squeezers that Mark built. Mine has an adjustable ram, so I can just screw it in and out as I may need to for various operations---like dimple dies vs rivet dies.

Who knows what the current Numatx manufacturer has changed.

Tom
 
Resurrecting this thread... again.

I've put 6x 60cc charges through my Numatix (which came with fluid already in it) and I just can't seem to get it to fully squeeze -4 rivets.

While bleeding, I've got the C-squeezer on a shelf near the ceiling of my garage. The hydraulic line is almost vertical. I must be doing something wrong. Any hints are greatly appreciated.

I had the same problem as you and thought it was a bleeding issue but I don’t think it is. I have the newer nonadjustable ram version. I was using two thinner squeezer dies at first and couldn’t get a full squeeze on -4 rivets in thinner material no matter how high I turned up the air.

I discovered the only way I can get it to fully squeeze -4 rivets in thinner material is to use a 1/4” or thicker squeezer die for one of the two dies. This reduces the needed length of travel for the ram and now I get consistent rivets in all material thicknesses at about 85psi. I haven’t had to bleed again since I discovered that and I have squeezed hundreds of rivets with the tool.
 
Gee----just go back to the adjustable ram.
Yes---mine was a pain to bleed, but once I finally got it done, it was fabulous. Dont use it much any more ( it cant crimp hoses:eek:) but its still a great unit.
Tom
 
I routinely add a washer under one or both dies - 1149|0363 I believe to make minor length adjustments.
 
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I never used the adjustable ram on a numatx, but it seems to function great without it. No matter the thickness of the materials or length of the rivet, I get the same shop head size on every rivet without having to make any adjustments. I love this tool.
 
I'm blown away by the number of replies within 12 hours of my (first-ever) question. What a great community!!! I'm so grateful for the suggestions.

Using the long ram with the short die and a couple of washers, there's enough travel to clamp the material, but the rivet DOES NOT get squeezed properly (see pictures). Switching to the long die, the rivet IS squeezed properly (see picture (of my poor riveting skill)).

However, when I use the long ram with the long die, the rivet is longer than the gap between dies, so I have to start with the short die and then change to the long die.

Also, I've put a ton of Teflon tape on, but the bleed plug keeps backing itself out.

This can't be right, so... I'm going to try to bleed it again.

I should mention that I'm testing with rivets slightly too long, just to see the worst case.

Two days covered in transmission fluid... would love to have this resolved.
 

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I'm blown away by the number of replies within 12 hours of my (first-ever) question. What a great community!!! I'm so grateful for the suggestions.

Using the long ram with the short die and a couple of washers, there's enough travel to clamp the material, but the rivet DOES NOT get squeezed properly (see pictures). Switching to the long die, the rivet IS squeezed properly (see picture (of my poor riveting skill)).

However, when I use the long ram with the long die, the rivet is longer than the gap between dies, so I have to start with the short die and then change to the long die.

Also, I've put a ton of Teflon tape on, but the bleed plug keeps backing itself out.

This can't be right, so... I'm going to try to bleed it again.

I should mention that I'm testing with rivets slightly too long, just to see the worst case.

Two days covered in transmission fluid... would love to have this resolved.

It appears that your throw is adequate - as you can reach the material fully. With adequate throw, the problem is likely that air remains in the system….

I had to bleed mine maybe twice before getting full force. So something is not right.

That is odd that your plug us backing out. Maybe that is a leak source? Teflon tape works poorly. Consider Loctite 545.

Are you getting air out each time you bleed?
 
That is odd that your plug us backing out. Maybe that is a leak source? Teflon tape works poorly. Consider Loctite 545.

I was hesitating to use anything other than Teflon tape since that's what's mentioned in the manual:
Reinstall the c-squeezer bleed plug and tighten. Use Teflon tape on the pipe threads. DO NOT OVER-TIGHTEN the fill plug. Refer to Figure 8.
Have you tried Loctite with success?

Are you getting air out each time you bleed?
I have the C-squeezer as high above the intensifier as it will go and I haven't been looking at it (sounds stupid as I type it here). I'll try again and see what I can see. I might set up a GoPro to Have a better look also.

Thanks so much for your help!
 

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I prefer Loctite 545 to Teflon tape because it is designed for sealing high pressure systems (heavy equipment hydraulics etc), and it does not create a
risk of particulate getting in your system. Teflon tape is widely used - and works fine most of the time. But if I had concerns about a particular fitting, I would prefer the 545.
 
I've made a video of my bleeding setup in case there is something super obvious that I'm doing wrong. Sorry for the terrible audio.
https://youtu.be/qJtfcrW70gE

I've tried to push through and do some riveting with it anyways. Transmission fluid has started coming out of the hole at the front of the C-squeezer just a little bit with each squeeze. I'm guessing that is not normal. I will contact Numatx on Monday and post the results here.

I prefer Loctite 545 to Teflon tape because it is designed for sealing high pressure systems (heavy equipment hydraulics etc), and it does not create a
risk of particulate getting in your system. Teflon tape is widely used - and works fine most of the time. But if I had concerns about a particular fitting, I would prefer the 545.
Understood. Thank you for the additional information! That puts my mind at ease about using it.
 
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