• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.

Cutting foam sheets... with a needle!

Sorry for the late reply, Britt. Currently no electricity with the winter storm in N Texas... two days of 5-8" of snow on the ground and near-0F temps at night. This has resulted in so-called "rolling black-outs" that have resulted in 12+ hour outages. Thankfully my old farm house has propane tank for heating and cookstove...

No better suggestions than what you've already got wrt belts, etc. Grub screws always need to be checked. Series or parallel connection of dual motor axis? If parallel, one motor can skip steps while the other doesn't and could result in wonky shapes.

I can't think of anything more at the moment. Hopefully I'll have stable electricity within a couple of days. Stay warm! -- David
Praying that they get the electricity situation rectified soon. Stay safe and warm In the meantime.
 
Sorry for the late reply, Britt. Currently no electricity with the winter storm in N Texas... two days of 5-8" of snow on the ground and near-0F temps at night. This has resulted in so-called "rolling black-outs" that have resulted in 12+ hour outages. Thankfully my old farm house has propane tank for heating and cookstove...

No better suggestions than what you've already got wrt belts, etc. Grub screws always need to be checked. Series or parallel connection of dual motor axis? If parallel, one motor can skip steps while the other doesn't and could result in wonky shapes.

I can't think of anything more at the moment. Hopefully I'll have stable electricity within a couple of days. Stay warm! -- David
Thanks David,
Wow, this storm has been a rough one for you. I sure hope it lets up soon and your power gets back to normal.
The Y axis steppers are in series. I have rechecked the grub screws too. I will let you know when I get it sorted out. My Y axis belts are a little loose so I am 3D printing some brackets to better secure them.
You should be able to see the left and right side are slightly flat in my photos.
Take care and stay warm!
Britt
 

Attachments

Hey guys, just a couple of questions. I've been running my needle cutter for a while now but I still have an issue with the needle coming off every 7-10 sheets. I think the issue is with a buildup of hard black material on the shaft of the needle that will eventually catch in the MIG welder tip and cause the needle to pop off the bearing. I finally put some cotton ball above the mig tip to add some oil but I'm wondering if anyone else has had or heard of this issue. I read someone who mentioned a "crude" needle cutter that worked flawlessly for over 100 sheets and that is what I want lol I'm just wondering what I should change to make this a little better/more reliable.
https://photos.app.goo.gl/pcE4hQ4qc8MfRX6fA
I have a setup just like yours. Initially I had trouble with the needle coming off too. What solved my problem was to change to .025" wire that fully retracts into the MIG tip on the up stroke, use cotton with oil, and slow down the RPMs to around 6200. After making those changes I have not had a needle come off.
 

Wildthing

Legendary member
Sorry for the late reply, Britt. Currently no electricity with the winter storm in N Texas... two days of 5-8" of snow on the ground and near-0F temps at night. This has resulted in so-called "rolling black-outs" that have resulted in 12+ hour outages. Thankfully my old farm house has propane tank for heating and cookstove...

No better suggestions than what you've already got wrt belts, etc. Grub screws always need to be checked. Series or parallel connection of dual motor axis? If parallel, one motor can skip steps while the other doesn't and could result in wonky shapes.

I can't think of anything more at the moment. Hopefully I'll have stable electricity within a couple of days. Stay warm! -- David
News is today Sask Power (Saskatchewan Canada) will be sending power your way to help out :)
 
News is today Sask Power (Saskatchewan Canada) will be sending power your way to help out :)
I appreciate it, @Wildthing! The "rolling blackout" finally settled into a noticeable pattern (2-3 hours on, 2-3 hours off) most of the day yesterday and since sometime in the night, it's been on solid all morning. So, thanks, Saskatchewan!

In addition to electricity, water has been our big deal. Our "city water supply" broke and has been off for 3 days now... I'm about to go out and turn it on in a few minutes to see if there's any change. Hopefully my pipes aren't frozen so I can draw some up coffee water, flush the toilet, etc. We've been in single digits -- down to 1*F -- for several days, with clear nights and a 6"-8" snow blanket on the ground, so turning the water on for just minutes at a time is my normal routine... and the city supply issues just compounded the problems. But the forecast is for a high of 36*F on Friday so maybe the end is near! [I hear you laughing at us... you "northerners"! You don't have to deal with our summer heat... ;)]

20210215_091107.jpg


A pleasant surprise, I've finally finished a 4-1/2 hour 3d print that's been interrupted several times... so Prusa's recovery capabilities seem to be the real deal! :eek:

I really do appreciate the well wishes y'all have sent my way, guys! Everybody stay warm! :)

-- David
 
Last edited:
An update... I've had stable electricity for over 24 hours now. So thanks, @Wildthing (and any others) who sent some of theirs my way. Water is still a bust. Thankfully had a near-full "pallet" of bottled water for coffee and am using snow water to flush on occasion. Heat is not an issue as I have a propane tank and nice store-bought propane heater which keeps my little house quite comfortable. Still snow-bound but no need to personally get out on the streets (which are still pretty bad) and I have my daughter and family next door. So I'm doing pretty well. I feel a bit guilty, however, as the news is pretty heart-breaking about how much of the state is still in dire straits. Our forecast is to finally get above freezing, starting this weekend, so hopefully some relief is on its way. My prayers to all who are suffering and thanks to all who've sent their encouragement and well wishes -- and electricity! -- our way.

-- David
 

Wildthing

Legendary member
An update... I've had stable electricity for over 24 hours now. So thanks, @Wildthing (and any others) who sent some of theirs my way. Water is still a bust. Thankfully had a near-full "pallet" of bottled water for coffee and am using snow water to flush on occasion. Heat is not an issue as I have a propane tank and nice store-bought propane heater which keeps my little house quite comfortable. Still snow-bound but no need to personally get out on the streets (which are still pretty bad) and I have my daughter and family next door. So I'm doing pretty well. I feel a bit guilty, however, as the news is pretty heart-breaking about how much of the state is still in dire straits. Our forecast is to finally get above freezing, starting this weekend, so hopefully some relief is on its way. My prayers to all who are suffering and thanks to all who've sent their encouragement and well wishes -- and electricity! -- our way.

-- David
Just saw some reports last night with a lot of people dealing with frozen burst pipes and water coming out of the walls and ceilings plus they are doing the same as you melting snow for water.
 
Just saw some reports last night with a lot of people dealing with frozen burst pipes and water coming out of the walls and ceilings plus they are doing the same as you melting snow for water.
Certainly the burst pipes and water damage are bad enough but it is the folks with medical issues/equipment with no power that are suffering the most. There are video reports of literally thousands of city folks living in their cars for heat... apartment complex parking lots with rows of cars with engines running, some folks spending 10-12 hours or more in their car. God help them when they run out of gas... and 911 is of course overwhelmed with calls for help from folks literally in life/death situation. Lots of folks are genuinely in survival mode... and it's truly heart-breaking to see.

I've lived and owned homes in North Texas most of my life and dealt with burst pipes on occasion... usually outside faucets or pipes under pier-and-beam. When I moved to fast-growing Houston for 4 years in the early '70s, I was astounded to see that down there they actually ran water pipes through the attic in new construction... large developments with big, expensive, homes. My in-laws were insurance folks and it was mind-boggling the water-damage claims that they had to deal with. I'm sure those folks with water coming down from the ceiling and out of the walls are mostly those down in the southern half of the state... :eek:
 

rockyboy

Skill Collector
Mentor
Having lived through the horrible experience of having pipes freeze and burst in mobile homes as a kid, and my heart goes out to everyone dealing with this crisis. When I had the opportunity to renovate a house about a decade ago and needed all new water lines, I installed PEX flexible lines everywhere. While we were waiting for a plumbing inspector to come onsite during the construction, the entire water system was accidentally left full of water over night - and the entire system froze solid that night. The next morning listening to everything creak and crack as it thawed out was unnerving - but it survived without a single burst pipe or leak. The cost of the materials were a little higher, but the installation time for the plumbers was actually a lot faster than traditional copper so the money side evened out, and I recommend anyone with the opportunity to choose during new construction or renovation to look into installing a water system that can handle damaging temperatures.
 

Wildthing

Legendary member
Having lived through the horrible experience of having pipes freeze and burst in mobile homes as a kid, and my heart goes out to everyone dealing with this crisis. When I had the opportunity to renovate a house about a decade ago and needed all new water lines, I installed PEX flexible lines everywhere. While we were waiting for a plumbing inspector to come onsite during the construction, the entire water system was accidentally left full of water over night - and the entire system froze solid that night. The next morning listening to everything creak and crack as it thawed out was unnerving - but it survived without a single burst pipe or leak. The cost of the materials were a little higher, but the installation time for the plumbers was actually a lot faster than traditional copper so the money side evened out, and I recommend anyone with the opportunity to choose during new construction or renovation to look into installing a water system that can handle damaging temperatures.
Most new construction now they use pex almost everywhere.
 
I think we are pretty much out of the worst of it... and power has been restored to most of the state, last report I heard. I still don't have "city water" but it is supposed to climb above freezing today and I still have bottled water for coffee and plenty of snow to melt for flushing. I'm in my grandparents old farmhouse, built 1950-ish, so it's antiquated plumbing, repaired numerous times ad hoc with whatever materials were on hand... but mostly PVC pipe now. I drained back all the faucets in the house before it got too bad so hopefully it'll all still be intact once warmer temps have had time to do their magic.

I'm doing fine and Prusa is staying busy building a new Z-axis for a couple of machines...

20210219_101153.jpg


20210219_101220.jpg


Thanks again for all the kind words and well-wishes. Stay warm!

-- David
 
I think we are pretty much out of the worst of it... and power has been restored to most of the state, last report I heard. I still don't have "city water" but it is supposed to climb above freezing today and I still have bottled water for coffee and plenty of snow to melt for flushing. I'm in my grandparents old farmhouse, built 1950-ish, so it's antiquated plumbing, repaired numerous times ad hoc with whatever materials were on hand... but mostly PVC pipe now. I drained back all the faucets in the house before it got too bad so hopefully it'll all still be intact once warmer temps have had time to do their magic.

I'm doing fine and Prusa is staying busy building a new Z-axis for a couple of machines...
Thanks again for all the kind words and well-wishes. Stay warm!

-- David
David, what laser are you using on this machine? It looks like you are able to cut through 1/8" plywood with it.
Britt
 
David, what laser are you using on this machine? It looks like you are able to cut through 1/8" plywood with it.
Britt
Britt,

I've got several laser modules to play with... Banggood/Eleksmaker 2.5W and 3.5W units and a couple of Neje units, both discontinued "20W" and a newer model "30W". Been having a dickens of a time trying to cut any material with massive charring and inordinate number of passes. That was all without air assist.

So now I'm playing with air assist and getting a much better result. Here, the same gcode file is run, with (right) and without (left) air assist, on 1/8" plywood...

20210223_230950.jpg


20210223_232109.jpg


I recently purchased a little compressor, rated at 38 L/min, and have just started playing. I used a single line from the supplied manifold for the test above but have since removed the manifold and used larger tubing and an inflation needle (left over from early needle cutter development)... and it seems to be even better.

20210223_232312.jpg


Single, smaller, tubing from the manifold... directed at a fairly low angle to the material...

20210223_232318.jpg


Here, with larger tubing and inflation needle... directed at a higher angle to the material...

20210224_105732.jpg


20210224_105741.jpg


20210224_105757.jpg


I'm seeing that real air-assist is crucial to get clean cuts and minimal charring in both ply and solid wood. Those earring blanks my daughter is wanting is ~4mm pine, cut in 4 passes at 200 mm/min and 100% power with the Neje "30W" (5W-5.5W laser power)... note the clean little cylinder due north of the right-most earring blank. So far, it appears that there is less charring with multiple, faster, passes than with fewer, slower, passes. I also intend to see what the little Banggood lasers can do... now that I have the air-assist running.

Hope this helps. -- David
 
Britt,

I've got several laser modules to play with... Banggood/Eleksmaker 2.5W and 3.5W units and a couple of Neje units, both discontinued "20W" and a newer model "30W". Been having a dickens of a time trying to cut any material with massive charring and inordinate number of passes. That was all without air assist.

So now I'm playing with air assist and getting a much better result. Here, the same gcode file is run, with (right) and without (left) air assist, on 1/8" plywood...

View attachment 193549

View attachment 193550

I recently purchased a little compressor, rated at 38 L/min, and have just started playing. I used a single line from the supplied manifold for the test above but have since removed the manifold and used larger tubing and an inflation needle (left over from early needle cutter development)... and it seems to be even better.

View attachment 193552

Single, smaller, tubing from the manifold... directed at a fairly low angle to the material...

View attachment 193553

Here, with larger tubing and inflation needle... directed at a higher angle to the material...

View attachment 193554

View attachment 193555

View attachment 193557

I'm seeing that real air-assist is crucial to get clean cuts and minimal charring in both ply and solid wood. Those earring blanks my daughter is wanting is ~4mm pine, cut in 4 passes at 200 mm/min and 100% power with the Neje "30W" (5W-5.5W laser power)... note the clean little cylinder due north of the right-most earring blank. So far, it appears that there is less charring with multiple, faster, passes than with fewer, slower, passes. I also intend to see what the little Banggood lasers can do... now that I have the air-assist running.

Hope this helps. -- David
Wow, those cuts with air assist are fantastic. I am going to have to get a laser to play with!
 
Alright. Here's an update on my laser testing of late...

As previously stated, air-assist in crucial to clean through-cuts, in the minimum number of passes, in the various materials I've tested. As I shared above, I'm fortunate to have several laser modules to compare... so here are a few of my observations.

The following photos show the setups I've been testing. As air-assist is common to all, I've tried to devise a similar air-assist mount, using the same 38 L/min compressor and tubing/nozzle, for each of the lasers I wanted to test. There's a Neje "30W" (5-5.5W actual) laser module, a discontinued Neje "20W" unit, and finally a much-used little Banggood 2.5W unit I continue to use because -- frankly -- it seems to perform as well, or better, as the all higher-powered units I've tested.

So, here is the Neje "30W" unit...

20210226_150146.jpg


and the discontinued Neje "20W" unit...

20210226_182152.jpg


and the little Banggood 2.5W unit I've had forever...

20210226_191349.jpg


As I previously posted, I can cut 1/8" (3.125 mm) plywood and ~4mm pine (and other softwoods, willow?) in 4-6 passes with the Neje "30W" unit... at 200 mm/min feed at 100% power. I admit I was impressed with the improvement that air-assist brings to the party... but still had the nagging feeling I needed to compare these results with some of the other lasers I have. That's what led to devising the similar air-assist mounts shown above.

Bottom line... the little 2.5W Banggood unit IMO outperforms, or equals, both of the higher-powered units I've tested. In nearly every test the 2.5W unit was able to cut through the material in the same number of passes and with cleaner, less charred, edges. I set "best focus" for all laser units at the material's surface and left it there for all succeeding passes and the lower-powered unit's "kerf" is discernably smaller/finer and the laser power is better concentrated... enabling the beam to pierce the material through and cut more efficiently.

In the following photos, I've used the 2.5W laser to engrave at 1200 mm/min and 85% power and profile cut at 200 mm/min and 100% power, 6 passes. The linework on the earrings... and the signature on the Native American engraving, while not readable, is far finer and recognizable as a signature.

20210226_193905.jpg


20210226_200736.jpg


20210226_201429.jpg


20210226_201515.jpg


Of the Neje units, the "30W" unit seems to have a finer spot and focuses better than the discontinued "20W" unit. The build quality on both of the Neje modules is IMO quite nice and they don't have the quirk of unexpected laser firing on reboot/reset that so many have complained about with the Banggood/Eleksmaker units. I still have a Banggood 3.5W stashed away that I can test but I remember being somewhat disappointed that it wasn't noticeably more powerful than the 2.5W units I already had at the time.

Still some playing to do... but these are my thoughts and observations so far. As always... YMMV :oops::unsure:

-- David
 
Last edited:
Because my daughter is using a Banggood 3.5W laser and I'm trying to help her... I've been concentrating on my 2.5W laser once again, this time with air-assist. Here with 1/8" (3.175 mm) birch plywood and some "unidentified" (I think it may be willow...) solid ~4mm "found wood"...

20210226_201502.jpg


a couple of impressive-looking Native American fellows... I think this is Sitting Bull and the other fellow is a "medicine man"?

20210227_101240.jpg


in 3.175 mm birch ply, ~2.5 mm yellow pine, and the ~4 mm "willow" (which I especially like...love the darkish streaks)...

20210227_224444.jpg


All the engraving was 1200 mm/mm and 85% power -- without air-assist... and the profile cuts were simply 6 passes, with air-assist, at 200 mm/min and 100% power. The pine and willow were virtually cut through all the way round and required almost no coercion to extract... the ply, occasionally, required help in a couple of spots. I'm sure that with a couple more passes and/or slowing the feed rate just a titch, these can all be extracted with little/no effort at all.

For small work such as this, a bandsaw and belt sander will be a monumental help at slabbing/planking out limbs and scrap lumber to produce some really nice looking material to work with. It's truly neat to take "found wood" from the firewood pile and/or downed limbs and turn it into something truly impressive.

-- David
 
Hi everyone,

New here, trying to build myself a foamboard/cardboard cutter. I did the first dry run today and noticed a lot of side-to-side vibrations (due to needle resisting bending on far right and far left position). Is that normal? I've printed TimSav version with some dimensional changes (bearings are 7mm, modelled in some chamfers to avoid small washers), but haven't glued it together, so could it be because of that?

Also, I'm currently using 0.8mm wire for needle instead of 0.6 people keep mentioning, which is harder to bend, I guess, have anyone tried thicker wire or am I the first one? I want to be able to cut regular corrugated cardboard as well, so thicker needle made sense originally, not so sure right now )

Aaand also doing clothes pin spring for driving the needle instead of flywheel I've noticed people using currently. I remember some (long) time ago reading that clothes pin was preferred approach, it has changed now? If I just run the motor with that clothes pin springy thing attached - I don't sense any noticeable vibrations coming from it, so I guess it shouldn't be due to balance issues. Should I go to flywheel design? Which one is considered to be the workhorse version currently?

And yes, I do realize that doing everything by the book originally and then applying modifications would have made more sense ) but these bearing, wire thickness, motor, etc - I had lying around, did not have to order anything, which is nice. I can order everything recommended, it just would take more time )

Here's a video for reference:

 
Hi everyone,

New here, trying to build myself a foamboard/cardboard cutter. I did the first dry run today and noticed a lot of side-to-side vibrations (due to needle resisting bending on far right and far left position). Is that normal? I've printed TimSav version with some dimensional changes (bearings are 7mm, modelled in some chamfers to avoid small washers), but haven't glued it together, so could it be because of that?

Also, I'm currently using 0.8mm wire for needle instead of 0.6 people keep mentioning, which is harder to bend, I guess, have anyone tried thicker wire or am I the first one? I want to be able to cut regular corrugated cardboard as well, so thicker needle made sense originally, not so sure right now )

Aaand also doing clothes pin spring for driving the needle instead of flywheel I've noticed people using currently. I remember some (long) time ago reading that clothes pin was preferred approach, it has changed now? If I just run the motor with that clothes pin springy thing attached - I don't sense any noticeable vibrations coming from it, so I guess it shouldn't be due to balance issues. Should I go to flywheel design? Which one is considered to be the workhorse version currently?

And yes, I do realize that doing everything by the book originally and then applying modifications would have made more sense ) but these bearing, wire thickness, motor, etc - I had lying around, did not have to order anything, which is nice. I can order everything recommended, it just would take more time )

Here's a video for reference:

I have not went that thick for the needle. I use .025 wire needles. I did try some .03_ wire, I don’t remember the exact size, but it did not cut as nicely as the .025 did for me.
(Edit - I forgot to mention that I used the clothes pin spring for a while and abandoned it for the flywheel.)
 
Last edited:
Hi everyone,
...
Aaand also doing clothes pin spring for driving the needle instead of flywheel I've noticed people using currently. I remember some (long) time ago reading that clothes pin was preferred approach, it has changed now? If I just run the motor with that clothes pin springy thing attached - I don't sense any noticeable vibrations coming from it, so I guess it shouldn't be due to balance issues. Should I go to flywheel design? Which one is considered to be the workhorse version currently?

And yes, I do realize that doing everything by the book originally and then applying modifications would have made more sense ) but these bearing, wire thickness, motor, etc - I had lying around, did not have to order anything, which is nice. I can order everything recommended, it just would take more time )
...
Welcome to the party, @hudbrog!

Please recognize that this thread documents over 5 years (and, personally, another 5+ years before that...) in the *evolution* of needle cutter technology... a development process, done out in the open, and with input from many sources. There's not just one way to do anything here... and no "book" to go by. No kits, no plans, no step-by-step (other the Edward's TimSav)... just the sharing of ideas and testimonies from folks about what worked (or didn't work) for them. KISS and "using what you've got" is absolutely encouraged... and probably one of the best "teachers" you'll ever have. The "mousetrap and clothespin" cutters I did were really intended to demonstrate just that... and, that they performed as well as they did, was instructive and quite surprising. I know of one fellow who still uses the spring setup to drive the needle -- and testifies that he has cut hundreds of sheets of foamboard with it -- but most of us use some form of the flywheel and have to find a way to deal with the balance issues. But it can be done with a bit of patience and perseverance... and there are many varied and successful cutters out in the wild.

TimSav is a lightweight, "minimalist", machine that cuts foamboard quite well for many/most folks. The cutter head is also lightweight and compact... but probably not the best choice for thicker wire and tougher materials, like cardboard. Some of my earlier cutters did cut cardboard...

steg1.jpg

steg2.jpg


but were a good deal sturdier than Edward's cutter. I also used cardboard -- and even coroplast -- to "torture test" a few cutters along the way. The thicker wire can be used but you'll probably need to reinforce and "up-size" your cutter's dimensions to accommodate the stiffness of the wire and toughness of cardboard. Or, use the 0.025" music-wire, or similar, that most of us have used, and test it for yourself... I think you'll find it is surprisingly stiff and quite capable of cutting cardboard (or fingers!). Cutting foamboard will of course be a "snap" by comparison.

I've pretty well retired from the needle cutter game but there are still many here who should be able to give you some guidance. Stick with it and be patient... you'll get something that works eventually and learn a ton along the way.

Good luck! And, again... welcome!

-- David