PDA

View Full Version : THING HubCap V1



zugok
12-13-2017, 03:59 AM
Parts published here:

https://www.thingiverse.com/thing:2735871


I am getting close to finishing this printed alternate extruder hub...the HubCap V1.

After getting so many print failures in fine 70nm mode, I started looking into replacing the filament feed system, based upon what TommyDee and MegaloDon have already done with the FilamentHub and FTF Hub.

There is aspects of the both I like, such as Dons very complete cover and chip holder, but I also like the simplicity of Don's FH with the Bowden coupler directly threaded to the metal hobb-gear housing. I also found that my hub gets very warm so looking to find a way to channel the airflow from the stepper fan to the metal housing.

I also added neodymium magnets from HomeDepot to help secure the hub into place, as the clip is not very strong.

Here is a few pics, parts printed on my Taz 5. I will print them out on my Cube once all it actually working. Once it is all done and functional. I will post the STL's with the settings that worked for me.

Huge thanks to the other members of this forum for being so helpful.

2433

ztoddman1
12-13-2017, 05:15 AM
Nice!

TommyDee
12-13-2017, 05:20 AM
:o I L I K E IT! The magnets are a nice touch!

zugok
12-13-2017, 07:28 AM
Thanks.

The combination on fit+clip+magnets = secures the hub into place.

Printed in shitty S3D PLA, will print in ABS when design is final.

bolsoncerrado
12-13-2017, 09:21 AM
VERY nice! Gratz! :D

ztoddman1
12-13-2017, 09:23 PM
Just happened to take apart my old bulk filament with the switch and it is eager to try the hubcap!

zugok
12-16-2017, 11:13 AM
Thank you. I hope to have the final hubcap ready in a few days.

- - - - - - - - - -

I think I am going to make the hub a "complete kit" with a new nozzle file too.

Based upon measurements of the 3DS parts and re-imagining the (awesome) print head that Don made. The main PTFE tube goes all the way to the metal end, meeting with the thin PTFE.

IMHO making a screw-on end cap makes the part easier to print and maybe stronger too? Tests will tell. I hope to have all the parts ready very soon.

2434

The PTFe goes to the nozzle end where the thin tube is.

ztoddman1
12-16-2017, 01:29 PM
NIce! Like the screw cap at the hotend. Could you do a file with the M5 quick fitting?

zugok
12-16-2017, 07:00 PM
Thanks ztoddman

Yes I can, why would you want a M5 quick fitting, would it have an advantage?

Cheers

JH

TommyDee
12-16-2017, 07:35 PM
(make the hole around the metal tube somewhat larger. You only need a lip there...)

ztoddman1
12-16-2017, 08:41 PM
Cuz it so cute! no, was the first batch I ran across plus it was the one that TommyDee used in metal drive housing, plus didn't want different sizes scattered around. Cant find the ones I got but here are some similar.

https://www.ebay.com/itm/10X-M5-Male-Thread-to-4mm-Hole-Tube-Push-in-Connect-Straight-Quick-Fittings/151947623244?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649



Thanks ztoddman

Yes I can, why would you want a M5 quick fitting, would it have an advantage?

Cheers

JH

TommyDee
12-16-2017, 09:19 PM
I only use M5 threads on the fittings because it provides the stop for the Teflon tubing from the nozzle.
But even so, I find fittings with too small of a hole for the filament.

Also, M5 is a better fit directly in the driver mechanism.

Here is a version of the nozzle I've been printing with for a couple of months...

2438

ztoddman1
12-16-2017, 09:46 PM
Yessir, I second that and second the use of his nozzle. Wow that sounded bad. At any point. His design has worked flawlessly since I printed it and looking forward to trying yours zugok.

zugok
12-17-2017, 12:26 AM
I was not aware of another variant, thanks Tommy good work!

I can see the advantage of having the "transition" from a "Stock" 4.2mm PTFE tube to the 3DS thin nozzle tube at the top of the housing, as it is farther away from the heat source so less chance of jamming due to expansion.

As TD said using the M5 to join the different tubes is great. I will start work on Mk II, after my Hockey game tonight.


Cheers

:-)

TommyDee
12-17-2017, 04:45 AM
Nothing published on the housing. Todd and I are giving it a run for its money.

ztoddman1
12-17-2017, 04:49 AM
Nothing published on the housing. Todd and I are giving it a run for its money.

ANd I must say, money well spent, wait I was a beta tester but if I paid for it, money well spent!

zugok
12-21-2017, 08:25 AM
Almost done updates, thanks for the great feedback.

Now uses the same M6 fitting that I used on the Extruder housing. I only 3D Print the nozzle tip thread, for the fitting end I use a M6 Tap.

When I get some M5 fittings in from Amazon, I will make a M5 variant too. I hope to have the HubCap and Nozzle fully tested and running this coming weekend using ABS for the Hub and PC+ for the Nozzle.

Regards

2439

John H

ztoddman1
12-21-2017, 03:59 PM
Darn right, that looks sexy. Cant wait for the files!! Keep up the good work my man!

TommyDee
12-26-2017, 06:36 AM
Maybe you can carve some thread bits off the linked nozzle...


Tube length is 42mm if you decide to print the M5 version. Just keep the blob reliefs oriented.
The M6 version was for the 4mm tube-through fittings which can be merged with the 2.8mm tubing.

https://drive.google.com/open?id=141Veimv5ec97CNmwjkxSN2Dm4Svc3Cx_

zugok
12-26-2017, 07:31 AM
Sorry for the delay..

After tons of iteration and tiny adjustments I have nozzle files. One version is best suited for PLA since it prints more easily. The other for Polymaker PC-Plus. Early in my fit-tests I also tested in ABS but found it to be too soft at the time. Probably the PC+ version would print fine in ABS too. I have some PETG that I may try as well.

I drilled out the end of the M6 fitting so the 3DS tube will fit into it.

The Polycarbonate one is very durable (as expected) but tends to fit very tightly too (no flex!) . I will have to do a couple more fit tests.

I used Simplify3D to generate the Gcode, and some support should be used, at least for the PC version.

I hope to have print tests with the parts fitted in the cube done in a few hours.

The photos show a few of my "test shots". Blue is PLA, Orange/Black is ABS, white is PC+

Cheers and happy holiday.

2442

- - - - - - - - - -

Thanks TD, that is a good suggestion.

The link says "File not found"...?

Cheers

TommyDee
12-26-2017, 07:35 AM
oops, fixed...

zugok
12-26-2017, 08:01 AM
Got the files, thanks.


Cool design, I will give that one a shot!

I did consider putting the "side nub" on the cap but was concerned of the end coming loose if the nozzle would stick for any reason. If you look closely I "reversed" the end cap threads so when removing the nozzle from the cube heat block it could only tighten onto the end and not get stuck within the heat block.

Why is it so important the end nozzle hole is a small lip? I kept the hole smaller since I am thinking the extra material might help with strength?

Cheers....sleepy going to bed now....

JH

PS: What is the cylinder for?

TommyDee
12-26-2017, 05:07 PM
I was just looking at the 10mm thread to see what was possible and got carried away.

I did already drop a cap but it was easily retrieved. It was a cool printer though.

Main reason for posting them is the M5 and M6 thread. Functional right off the print bed.

Oh, and the smaller lip is just to pull the plastic away from the hot metal tube.

And the cylinder is to let the threads cool. Without something else to print, the M10 thread got pretty messy.

And for what its worth, the M10 thread clearance is 0.08mm radial.
It is a triple start rolled thread at 6mm pitch.
The thickness of the thread is 0.35mm
I'm sure this will come in handy someday.

zugok
12-27-2017, 06:42 AM
well dammit...70 nm prints ~1hr are failing on my left extruder. Extruder area gets too hot and filament clogs as extruder heats up. This is with HubCap (printed in PLA that is warping and cracking in the heat) installed with Capricorn tubing and newly printed nozzle. Clearly is seems that the left extruder motor, fan or something is going on the cube printer. Even when not in use there seems to be some warmth...

Right side extruder prints fine and does not heat up at all. Did a ~2hr print test with the PLA printed nozzle and it completed (right side) but there where several printing errors on the object that I suspect is due to the PLA softening in the heat.

IMHO I don't see how a PLA 3D printed nozzle is a long-term solution.

I have a second (new) Cube printer that I will test on, and use the Right side on the current cube. In time I may dispose of the printer and buy a new replacement, too much effort to try and fix considering how cheap they are right now...


Polycarbonate Nozzle next...


PS: I got some M5 fittings in the mail today. I will make sure to offer a nozzle that will work with an M5 tap. IMHO, M6 is better as the end can be drilled out large enough to fit the 3DS PTFE tube. M5 looks too small to do that.

bolsoncerrado
12-27-2017, 11:31 AM
Im curious on peoples opinions printing this in PLA.... The area does get hot at a time specially on long prints, so the PLA will eventually deform over time.... hmmmm

TommyDee
12-27-2017, 07:16 PM
I'm running a PLA printed nozzle running PLA for quite some time now.
At least 4Kg worth, running some very big prints.
So yes, it can be done.

I don't like ABS from my printer. It is slicker and layer-to-layer adhesion is not as good.
I've run ABS with the PLA nozzle and it did deform some but the print finished fine.
Made a small mod in the nozzle but hadn't tested ABS again.

- - - - - - - - - -

The attached has a 4.5mm pitch on the M10 thread (vs. 6mm).
Still worked right off the print-bed.
Still 42mm of internal tubing for the M5 fitting.

Print 200um, strong, cross.


Check the hole in the M5 fittings.
I've reported this before but I received a batch with a hole smaller than 2mm.

Zugok, they make M6 fittings already drilled for 4mm tube-through.
I still cannot figure out a good reason for that one.

However, there are a lot of brass PC4-M6 fittings that have a bad thread.
It is neither 1mm pitch nor a full M6 thread.
They simply don't fit anything correctly.

- - - - - - - - - -


Im curious on peoples opinions printing this in PLA.... The area does get hot at a time specially on long prints, so the PLA will eventually deform over time.... hmmmm

The only part under stress is the distance from the spring rest (top, not the push nut end) to the top of the nub.
If you remove a hot hot-end, then the spring will be working against the cap.
Best to let things cool off before removing the hot-end.
The only deformation I've seen to date is the body would bend a little.
I added some stiches in the print and that took care of that.
I have a feeling it was more due to unequal thermal expansion than deformation.

I'll give this new version some time on the printer and see what it does.

zugok
12-27-2017, 09:46 PM
Thank you TommyDee!

It works in PLA, but as noted by TD, a person needs to wait for the head to cool before removal (I tried a few hot.. but one got stuck, another fell apart). As I had hoped to make it more idiot proof (meaning myself..) so PC seems important.

I do have my nozzle working with Polycarbonate, but honestly the way it is printed (with the silly loop I put on top...) requires tons of clean-up. The whole point was to create a nozzle the would be easier to print. My design does do that reasonably well in PLA as print cleanup is minimal, but it is much harder in Polycarbonate.

Helps to step away from a project for a few hours....

TD, if I continue to revise it all I would do is end up with a design very similar to yours, perhaps with the nub on the main body, and maybe the horizontal side bearing-lock groove added, why did you leave off the horizontal groove?

During my tests I discovered that adding a filament channel to my "HubClip" might help keep the filament in alignment. I am testing a variation with the channel now.

I am so sorry that I have not posted the files yet, I don't want to release a file that is broken and waste other people time and filament.

The working files need to be ready this week to print this... (it is about 20 STL files setup for the Cube...)

2444

TommyDee
12-28-2017, 05:19 AM
I don't post files that are not done either so that is understandable.
I'm just throwing the file out there if someone wants to play with it.

The horizontal stripe doesn't need to be there. It is a result from turning the stock nozzle in the heater block.

- - - - - - - - - -

WRT your filament driver motor heat issues...

The only thing that should warm these motors up is running very hard filament. This is where the cube doesn't flex... not even a little!
I've noticed the effort required to push a gritty GITD that required a little extra heat, as well as some white stuff that felt much the same way.
Even used up a roll of super-hard silver by cutting a small V-groove in the driver gear. Used up the whole kilogram that would otherwise have been trashed.

So a failed bearing in your driver could cause issues that include heating up the driver mech. It could also be the square drive. If the motor is working hard driving the mech, then this junction between the machine and the mech will also heat up. You could oil the shaft to ease that level of heat inducing friction. Figuring out where the heat is coming from should help diagnose this. The only direct contact between the motor and the mech is the shaft. Shorted winding perhaps? Ohm meter! (Crimped motor or fan wires shorting under a plastics screw boss?)

Unfortunately, the stepper requires a digital pulse sequence to work so unless you have some stepper drivers laying around, it is hard to test the free running current of the stepper. That is the easiest way to diagnose the motor itself. ...or $10 and you get a new drop-in replacement motor.

So next time you are inside the machine, unplug the motor and see how easy it spins. Maybe it is a dry bearing or a foreign object interfering with the rotor.
Stepper tend to cog but not be restricted. And is the fan spinning at the bottom of the housing? I know you've talked about it, but never confirmed it actually works.
If you spec out that fan, you will find it should be a fairly high velocity fan. It is rated well above the norm available on eBay. I did have to replace mine.
Remember that steppers in a shorted configuration acts like an electric brake. That is why I recommend unplugging it to test its free running condition.

zugok
12-29-2017, 12:54 AM
My testing is complete, I will have the Cube Hub files posted later today....whoo hoo!

Thanks TD for the great assessment.

The hardest filament I have run was some eSun PLA+, noting exotic. I does seem like a failing stepper, if I can get a replacement for ~$10 that that might what I will do. I doubt it is the fan as the air-low between each side is similar still, simply cool air on one side and warm on the other. I will find out for sure when I take the Cube apart.

I am a little burned out of 3d printer repair thanks to my Anet A8/AM8 (CCC...Cheap Chinese Crap). Thankfully my Taz5 "just works" but it has a slight z-banding(for now...) that is typical from 3D printers that use a Z lead screw. What i love about the cube...no Z-banding!

I am not an engineer so I am not aware of some details of how the steppers work, I appreciate your advice and enlightenment. When I get to "cube-repair time", you advice and tips will likely be essential. Again thanks.

Would you mind sharing a link, for the stepper replacement you found ,and maybe the fan specs/replacement?


Cheers

JH

- - - - - - - - - -

STL's published here:

https://www.thingiverse.com/thing:2735871

Please LMK of any issues.

TommyDee
12-29-2017, 01:17 AM
Don posted the info but I cannot find it for anything. Bo?

oh, wait...

zugok
12-29-2017, 07:07 PM
Thanks TD for replying, sadly the Stepper Motor image is too blurry to read.

https://www.youtube.com/watch?v=f4zyjLyBp64 :-)

I printed your TestCap nozzle in ABS and while the fit was tight for the tip it seems to work. In PC+ the gap between the body and cap needs to be greater as it is too tight.
Will reprint later in PC+ with adjustments. The M5 nozzle design tends to print well the M6 design tends to fail and 100nm.

Did a 4+ hr print with the HubCap, HubClip and Nozzle in eSun PLA+ at 70nm., success! Sadly my 7+ hour print last night ended up in a layer shift + spaghetti...no clogging at least!

TommyDee
12-29-2017, 07:44 PM
Hahaha... yes, I tried to find it on ebay too. They have 4,000 of them!

We need Don's or Bo's help finding the original post.
It is Don that posted the part number and I cannot find it again.

MegaloDon
12-29-2017, 10:30 PM
I couldn't find the damn post either! :rolleyes:

But I did find the link to where I ordered mine. :D
https://ultimate3dprintingstore.com/products/nema-17-hybrid-step-motor-17pm-k374bn01cn

- - - - - - - - - -


Did a 4+ hr print with the HubCap, HubClip and Nozzle in eSun PLA+ at 70nm., success! Sadly my 7+ hour print last night ended up in a layer shift + spaghetti...no clogging at least!

Have you tried this?
https://www.thingiverse.com/thing:1764253

zugok
12-29-2017, 11:36 PM
Thanks Tommy and Don. I ordered one. :-)

Also, thanks Don for stabilizer link. I was not sure what I was going to do other than keep print times to shorter times, I will definitely use that! The fail happened on the print with several parts on supports, I could of done a better job positioning them. :-)

PS: The print head is holding up after about ~5hrs at 70nm. Also I was able to remove the tip without it coming apart when still warm, but I have been noticing that the metal nozzle end seems to stick a bit more. I suspect that TD's twistcap will work even better once I can print a working one in PC+. The PC+ is darn tough!

Cheers

ztoddman1
12-31-2017, 02:02 AM
Lawd, step away for a few days and what a surprise when I came back! Awesome work Z, can not wait to run this puppy tonight!
Where did you put the magnets? Just glued them to the clip so they can attach to the drive mechanism>?



My testing is complete, I will have the Cube Hub files posted later today....whoo hoo!

Thanks TD for the great assessment.

The hardest filament I have run was some eSun PLA+, noting exotic. I does seem like a failing stepper, if I can get a replacement for ~$10 that that might what I will do. I doubt it is the fan as the air-low between each side is similar still, simply cool air on one side and warm on the other. I will find out for sure when I take the Cube apart.

I am a little burned out of 3d printer repair thanks to my Anet A8/AM8 (CCC...Cheap Chinese Crap). Thankfully my Taz5 "just works" but it has a slight z-banding(for now...) that is typical from 3D printers that use a Z lead screw. What i love about the cube...no Z-banding!

I am not an engineer so I am not aware of some details of how the steppers work, I appreciate your advice and enlightenment. When I get to "cube-repair time", you advice and tips will likely be essential. Again thanks.

Would you mind sharing a link, for the stepper replacement you found ,and maybe the fan specs/replacement?


Cheers

JH

- - - - - - - - - -

STL's published here:

https://www.thingiverse.com/thing:2735871

Please LMK of any issues.

zugok
12-31-2017, 04:03 AM
regarding magnets...yes. off to hockey....

Cheers

JH

ztoddman1
12-31-2017, 12:07 PM
great! Go PENS.

zugok
12-31-2017, 08:49 PM
great! Go PENS.

Whoo hoo.. 2x ~7hr 70nm print success with Hubcap/Hubclip/Nozzle. I have noticed that my cube get an error T24 when dong a filament purge, but still prints?

heh heh... I am a Flames/Sharks/whoever is playing Tampa or Anaheim fan.....

I got one assist last night, still lost. Any day I play hockey is a good day.

ztoddman1
01-02-2018, 12:40 AM
. Any day I play hockey is a good day.-- Yessir!
Tried to print your hubcap, it stopped about 1/2 way, will attempt it with the other side and see if it works. Did get the nozzle and cap printed!

zugok
01-02-2018, 03:25 AM
Sorry to hear about the print, when you mean "it stopped", did you get a filament jam? I have not tried to print the hub/clip/nozzle with the Cube3, I used my Taz 5. When I have time later on I will.

I have printed several tests of the nozzle+cap on my Taz5, w PLA, ABS, and PC+ . I have 4 of the "published" nozzles printed in PC+, and I have been printing with one in the "Right" side for ~ 48 hours with several prints. It is still going....


Here is a a pair of hub/clips printing in ABS on my TAZ5
2447

ztoddman1
01-02-2018, 01:51 PM
No jams, just stopped like it was completed but only half was way finished. I tried on the right side filament and it worked.

TommyDee
01-02-2018, 05:55 PM
A 30 second chip disconnect can also stop a print.

Ap0c4lyptyc
01-02-2018, 08:44 PM
How long does this usually take to print? I loaded it up on my Cube and it said it was going to take 20ish hours? For the cap and hub. Does that sound right?

zugok
01-02-2018, 09:22 PM
That seems really long... if you are printing at 70nm...perhaps?

Printing at 200nm should work well.

:-)

Ap0c4lyptyc
01-02-2018, 10:14 PM
Nah it was actually at 200. I had everything set on the "quickest" settings I am pretty sure. I will reload everything tonight to see if maybe I just goofed something up or something. I AM still kind of a noob with this printer so :p

zugok
01-02-2018, 11:37 PM
There are a number of ways to trouble-shoot this.

#1 Make sure the object in flat on the Z plane (Y is 3D software...).
#2 Re-export the .cube file.
#3 Make sure the file is centered, only one object at a time.
#4 Rotate the mesh 90 deg in Z (Y is 3D software...), make sure it remains flat on the build plane.
#5 Try setting WO supports....?
#6 Perhaps try to print an object of similar size...?
#7 Try slicing in Windows, vs OSX.
#8 Use a different slicer....maybe. If you are unsure of what you are doing with may be difficult.

Cheers

JH

TommyDee
01-04-2018, 06:03 PM
zugok; what pitch did you end up with on the cap thread?

zugok
01-04-2018, 09:14 PM
Hey TommyDee, thanks for asking.

I did not add the thread you suggested/provided to the top of the nozzle yet, sorry. I am not sure what existing tip thread pitch is, I made several adjustment during print tests to get it work with PC+.


The Nozzle in my Cube 3 is still seems to be working fine, with almost constant printing since last Saturday. The longest print so far was ~18hrs.

ztoddman1
01-04-2018, 10:05 PM
i finally got the clip to print. Had to rotate it, flip it, spin, etc to make it work but I got it. I tinkered with your nozzle to accept the M5 push fitting. of course, dropped the nut from the hotend so Im at a standstill till I find it.

TommyDee
01-05-2018, 01:09 AM
Which nut did you drop, Todd? I don't see a nut in the build pix.

https://cdn.thingiverse.com/assets/d9/3f/41/bf/99/parts.jpg

- - - - - - - - - -


... I am not sure what existing tip thread pitch is, I made several adjustment during print tests to get it work with PC+.
...
I was just only curious to see if I could have a triple start pitch about the same. Turns out yours is a 1.5mm pitch. I am planning to test a 3.6mm triple start pitch. The 4.5mm pitch is works nicely.

And no worries about implementation. Post what you like and what works. I doubt I'll ever be able to print in PC+.

ztoddman1
01-05-2018, 01:34 AM
I called it a nut, its that one that goes around the hot end that the spring is against.
THIS GUY---http://www.marshallshardware.com/products/product.aspx?pid=2-411-641-279-12447&lid=1

zugok
01-05-2018, 01:42 AM
I am sorry it was so hard to print on the Clip on the Cube.

I will try it on my own soon, after I find a way to address supports on the cube as Cube Print supports really mess things up... Hello Meshmixer....


I doubt I'll ever be able to print in PC+.

This was the first time I printed using PC+, so I could probably have done better w the threads.

TommyDee
01-05-2018, 02:56 AM
I called it a nut, its that one that goes around the hot end that the spring is against.
THIS GUY---http://www.marshallshardware.com/products/product.aspx?pid=2-411-641-279-12447&lid=1

Oh, you got me there... yes, push-nut. How'd you loose that?

You might try ACE h/w. I suspect it is actually an SAE 1/8" diameter shaft version.

zugok
01-05-2018, 07:13 AM
I have an Ace hardware next to where I work, I will have a look tomorrow.

:-)

ztoddman1
01-05-2018, 01:36 PM
was adjusting the height of it using that guide and this wonderful frigid weather has my fingers cracked and didn't get a good grip on it. I'll find it eventually, good thing I have several cartridges and nozzles!


I am sorry it was so hard to print on the Clip on the Cube.

wasn't a big issue, just had to rotate it a bit so the clips were straight up. worked like a charm.

TommyDee
01-05-2018, 06:27 PM
If it helps, Todd, the push nut has plenty of iron to allow a magnet to help in the search.

zugok
01-18-2018, 07:53 AM
Great idea! I might try that in an effort to find one long-lost spring...:-)


PS: The PC+ Nozzle is still holding up. :-)

- - - - - - - - - -

Found a few errors in my Nozzle file, so I have adjusted it and doing more test prints on PC+

IMHO printing the nozzle on PC+ or Max is the way to go....

The original one still works, but the print require a lot of clean-up. New version should be much better.

TommyDee
01-19-2018, 07:59 AM
I wonder what could cause that.

I made a version that I suspect grew from the heat and pushed off the black bottom cover after about 10 minutes... twice!
On the other printer I ran a different nozzle of the same geometry and it printed perfectly.

One thing about plastics is that they grow a lot with heat. This is called CTE... Coefficient of Thermal Expansion.
If there is enough mass growing in the wrong direction, it can cause problems.

ztoddman1
01-21-2018, 01:20 AM
ok, so I ordered a box of the 1/8" push nuts and I can say, it is much better than the ones that came with it. I had to force it on using the jig MegaloDon designed where as the original one I could practically push on with my fingers. Now if we could only source the metal hotends we will be set!

TommyDee
01-21-2018, 10:31 PM
ok, so I ordered a box of the 1/8" push nuts and I can say, it is much better than the ones that came with it. I had to force it on using the jig MegaloDon designed where as the original one I could practically push on with my fingers. Now if we could only source the metal hotends we will be set!

I've flattened the tabs on the stock push-nut if they've been overworked. A common pair of pliers will do the trick. I measures the tube OD at 3.2mm where 1/8th inch is 3.18mm.