Cutting foam sheets... with a needle!

jhitesma

Some guy in the desert
Mentor
I tried a set of DRV8825 drivers on Rascal. Im using 1\32 stepping and they are high current. It really, really smoothed out the machine..

I think you can get a set from china cheap, if you want to mess with it. lol I know, who has the time.. Right?:p

Kevin

I'm actually running DRV8825's already. Never even bothered with the Awhatevers on the MPCNC since I had already upgraded my 3D printer do DRV's and was impressed with them. They do run MUCH quieter and smoother than the ones who's part number I can't remember right now.

Like I said - my big problem was I was running my current way too low for the past year. I finally turned it up a few weeks ago and the machine is still almost silent (other than any tools I attach) and much smoother than it was. Don't see any difference in cut quality on DTFB - but cutting ply, MDF, Lexan and PVC sheets I'm getting much better results than I had been.
 

TEAJR66

Flite is good
Mentor
Guys, I am loving this MPCNC! 12 minutes to cut up a sheet of foam. Great stuff. The LCD control, ramps/Arduino, and Marlin, it all just works. Makes everything simple for us simple folk.

Needle cutters, admittedly, are more arts and magic than hard science. But, once you get one dialed in, they are way more precise than I ever was with a blade.

Thank you to all of you for the inspiration, advice and assistance.
 
(old subtopic, sorry) Regarding the use of servos in place of steppers on the Z axis (and associated gcode transformation),
I've got a first test implementation of a solution in Marlin, which "intercepts" steps as transmitted to a stepper driver and translates them as servo commands to the servo pins of the RAMPS. While it was clearly to be used for the Z axis, it can also be used for X and Y.

I've got sources for an old RC1.1bugfix version. Would anyone be intsrested in that code ? Would you prefer it for an other version ?
 

RAGII

Member
Used Allted's laser housing, modded for Hicwic's quick-change mount...

View attachment 77216

Printed with yellow PLA, the nozzle cone lights up real purty...

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David,
my workplace recently got a Fusion3 3D printer so I am now able to print out many of these cool MPCNC attachments. I have a question on this assembly on how the "mounting ears" print out. I noticed that it stated no supports in the printer settings, but it looks like these would then be printing in mid air. (see picture below) Can you provide some insight as to how this prints?

fan mount.JPG
 

dkj4linux

Elite member
David,
my workplace recently got a Fusion3 3D printer so I am now able to print out many of these cool MPCNC attachments. I have a question on this assembly on how the "mounting ears" print out. I noticed that it stated no supports in the printer settings, but it looks like these would then be printing in mid air. (see picture below) Can you provide some insight as to how this prints?

View attachment 96403

It's been a long time since I printed this. I must admit to a bit of awe/amazement at how good [some] things print... even when it looks to me, beforehand, like they will need support; i.e. I think this was one of those things. This is where a 40mm fan sits so, even if its a bit ragged/ugly, it should still provide enough support for the fan... but I'll bet it will surprise you just how nice it handles this ;)

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jhitesma

Some guy in the desert
Mentor
RAGII - the key to that part printing is that if you look at it closely you'll see the bottom of those supports are angled. So they "grow" out from the side gradually and build their own support.

Now that you've got your MPCNC working well you should print up an extruder mount and start using it as your own 3D printer so you don't have to tie up the one at work ;)


TEAJR66 - Looks great! And looks like you fly as well as me with that much reinforcement tape :D
 

RAGII

Member
RAGII - the key to that part printing is that if you look at it closely you'll see the bottom of those supports are angled. So they "grow" out from the side gradually and build their own support.

Now that you've got your MPCNC working well you should print up an extruder mount and start using it as your own 3D printer so you don't have to tie up the one at work ;)

I am saving up to get a real Prusa printer. For the most part the work 3D printer sits idle so I figure it needs some "exercise". There has definitely been more personal projects printed on this then work related.

I have too many other projects waiting to be tried on my MPCNC to tie it up 3D printing. :D I have cut over 20 planes on my MPCNC, lasered out firewalls and control horns and have done some Dremel engraving (works but really need the right tool).

Mirror etching, lexan engraving, and laser etched signs are on my to do list. Seems like when I start on one of these I need to cut another foam plane.

Thanks for the insight guys.
 

iGull

New member
I've got sources for an old RC1.1bugfix version. Would anyone be intsrested in that code ? Would you prefer it for an other version ?

Hi

Yes, I'd be really interested in seeing it ! I'm running the latest version 1.8.1 however :)
TBH, just the marked code for the servo mod would be fine.

Cheers

Neil
 

jhitesma

Some guy in the desert
Mentor
Well, Monday is the deadline for Ryan's MPCNC video contest...and since I've been busy I haven't had any time to prepare anything.

Guess that's a good enough excuse to make my vac table finally...and try to film it :D

I was going to make my own plenum...but mobeasts looked like too much fun to print so I had to give it a go:

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I love watching that kind of print grow :)

And used just about the full Z of my printer:

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If I hadn't done the Z mod this would not have fit! As it was it was tall enough that the extruder kept bumping my LCD and pushing it around...and for the last inch or so the back parts didn't get any cooling fan because as the print head went to the right the cables rubbed against the cooling fan and caused it to stop. But...it came out!

Started cutting up a vac table...but...my MPCNC went a little crazy again, I turned my back for a few minutes so not sure just what happened. But It acted like it did the crazy thing it would do when I'd reset zero but I hadn't reset zero...so not sure what happened this time as I've cut closer to the edges of foam board many times before. Going to give it another go here in a few.

We'll see if I get this playing nice or not soon ;)
 

jhitesma

Some guy in the desert
Mentor
And I've now officially joined the vac table club :)

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Slightly risque shot of it's exposed bottom :eek:

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If anyone wants the onshape project is here:
https://cad.onshape.com/documents/1...ceddd98c4843c1a032/e/3a917dd7e54ec0a2794e238a

Screen Shot 2017-10-22 at 12.19.58 PM.png

Just right click on the 3 sketches and export them as DXF.

I glued the three sheets together with Krylon EasyTack so it should be possible to pull them back apart if I need to replace one or more layers. I mean...it's only $3 worth of foam and about 45 minutes of cutting to make a new one - but if I can get away with just replacing one sheet that takes 14 minutes to cut instead why not ;)

I left the bottom slots exposed so it sucks itself to the table. I didn't even glue in the vac adapter, just cut the slots for it slightly undersized (I didn't include them in the CAD, I just cut them manually since I wasn't sure which adapter I'd be using when I started cutting this.)

It is a little louder in my shop with the vac going...would like to find a quieter vac to run this off. But it works. Now I just have to finish editing the video of making it for Ryan's contest and then add some positioning marks on my table to show where to put it for actually cutting foam! Oh...and figure out what to cut as a test....I really don't need to cut anything right now...I've got a couple things cut and waiting for assembly sitt...but gotta give this a try soon since I've put off building it for so long!
 

dkj4linux

Elite member
And I've now officially joined the vac table club :)

View attachment 96702

Slightly risque shot of it's exposed bottom :eek:

View attachment 96701

If anyone wants the onshape project is here:
https://cad.onshape.com/documents/1...ceddd98c4843c1a032/e/3a917dd7e54ec0a2794e238a

View attachment 96703

Just right click on the 3 sketches and export them as DXF.

I glued the three sheets together with Krylon EasyTack so it should be possible to pull them back apart if I need to replace one or more layers. I mean...it's only $3 worth of foam and about 45 minutes of cutting to make a new one - but if I can get away with just replacing one sheet that takes 14 minutes to cut instead why not ;)

I left the bottom slots exposed so it sucks itself to the table. I didn't even glue in the vac adapter, just cut the slots for it slightly undersized (I didn't include them in the CAD, I just cut them manually since I wasn't sure which adapter I'd be using when I started cutting this.)

It is a little louder in my shop with the vac going...would like to find a quieter vac to run this off. But it works. Now I just have to finish editing the video of making it for Ryan's contest and then add some positioning marks on my table to show where to put it for actually cutting foam! Oh...and figure out what to cut as a test....I really don't need to cut anything right now...I've got a couple things cut and waiting for assembly sitt...but gotta give this a try soon since I've put off building it for so long!

Jason,

I'm thrilled with your vacuum table build. You and Moebeast have really inspired me to get going again... I've fallen behind.

Mixed feeling galore, my daughter and family have just moved to San Antonio... he's taken a job there. And rather than let my main house (that they've occupied -- and remodeled -- for the last several years) sit empty... I'm moving in! What a change! Instead of a cluttered, cramped, space I'm now rattling around, all by myself, with room to spare. And I'm lost!

I'm really enjoying the uncluttered look/feel of the place (inside), so am really trying to take my time moving stuff in... I still want it to be presentable for when they are able to visit. So I've decided on a bedroom to be my workspace and am really trying to take the opportunity to get organized and set it up with just the stuff of current interest.

Anyway, with all the new-found space in the house/deck/shed I'm ready to tackle a new project. I had thought of taking on Moebeast's foam cutter (it's such a neat design) but now I'm thinking I should go a ahead and build a full-blown, if not full-sized, LowRider... most probably on my deck. I've moved my 3d printers over and am trying to shelve them, ala Ryan showed in his V1 Engineering HQ tour... I've got the Prusa I3 Mk2S, and two FT 2020's (kids are in an apartment now and didn't have room for their 3d printer)... still working on the shelf spacing...

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the shed and chicken yard...

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the deck...

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I need to stop... I'm not sure that this is making any sense. But I did want to acknowledge the good work that you are doing... keep it up! It's not falling on deaf ears! ;)

-- David
 
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jhitesma

Some guy in the desert
Mentor
Wow David, looks like you've got a lot more room now! Can't wait to see what you do with it? How's that C beam machine coming along BTW?

The vac table works...just used it to cut my first sheet. Not sure how I feel about it yet. The vac adds a lot more noise...and my shop vac doesn't seem very happy running that restricted that long - the exhaust from it was getting awfully warm. May switch back to my old shop vac I don't care about as much so I don't risk damaging the good one until I do some more research on how that affects a vacuum. Would like to find a cheap quieter household vac to run it off...and mount it outside the shop.

But it does hold foam great and much flatter! However that's also exposed that my machine is still not leveled as well as I wish it was...or that my rails have a bow in them somewhere. So gotta do some more experiments and measurements there. Bummer is I need the vac table on to make the measurements so that means more noise :p

And I did get the video of me making it tossed together in time for Ryan's contest:


Ran a bit longer than I meant for it too. I couldn't get iMovie to speed up the cutting segments more than 20% (I tried using a manual setting of 200% but it kept going back to 20%) and was running out of time to get it uploaded...so had to do the best I could. Wonder if anyone will actually watch an hour of my machine mixed with me talking about it :D

Got one more sheet to try and cut tonight though so gotta get it fired up! Will talk more tomorrow ;)
 

moebeast

Member
David, if I lived alone, the whole house would be full of projects, or interesting junk that could be a project. I admire your intention to limit your workshop to the bedroom. I am currently limited to my garage, and am running out of walking space.

Jason, I'm glad you got the vacuum pad made. I ended up putting a dab of hot glue in each corner to fix mine to my new machine so I don't have to align it each time. If you already have inserts in your table, maybe you could put some small pieces of wood in your bottom layer that you could screw down through the wholes in the top.

I've also found that a small "leak" provides cooling air for the vacuum and still has hold down power. But it does add to the noise. Kevin put his vacuum in an insulated box, and it is super quiet. That might be my next project.

And finally, I did actually watch the whole video :)
 

jhitesma

Some guy in the desert
Mentor
Jason, I'm glad you got the vacuum pad made. I ended up putting a dab of hot glue in each corner to fix mine to my new machine so I don't have to align it each time. If you already have inserts in your table, maybe you could put some small pieces of wood in your bottom layer that you could screw down through the wholes in the top.

Yeah, my long term plan is to build a wooden frame it can sit in (and which will help line up my workpiece) and which bolts down. I'm kind of thinking a plate with a ridge on the left and bottom sides about 5mm taller than the vac table. I don't want to glue it to my table since one of the main reasons I wanted a vac table was so I could switch it out quicker/easier than my pink foam :) I wouldn't actually attach the vac table to the plate - still just let it suck itself down...it would just give a quicker more reliable way to line things up.

For now I just drew two lines on my table and line it up manually before turning on the vac. Works...but if I get the workpiece a little crooked it can be tricky to re-align things.

I've also found that a small "leak" provides cooling air for the vacuum and still has hold down power. But it does add to the noise. Kevin put his vacuum in an insulated box, and it is super quiet. That might be my next project.

Yeah, I'm either going to have to find a quieter vac or move this outside if I stick with it! I considered a leak but didn't want to risk losing too much suction, will have to play with that I guess. So far my research doesn't seem to indicate it's bad for the vac to run them like this...but it still worries me.

And finally, I did actually watch the whole video :)
Thanks, and sorry for the slow machining sections (and my rambling.) I actually had iMovie set to speed the machine bits up 200% - but for some reason it kept reverting to 20% instead :p Would have shaved a lot of dead time out if I could figure out why it kept doing that :mad:

Second sheet cut with the vac table last night went well...but I did run into your "problem" with pieces coming loose "too easily" now :D The cut out parts wanted to stick to the waste board when I pulled up the remnants of the workpiece. I think this is partly due to my needle being bent. It's causing more friction and the needle is running hotter than normal, so I think the foam is melting slightly. It's also causing my cuts to be angled so I need to fix it. I also ran my cuts deeper since my first test with the vac table they were a little too shallow...but I later noticed that I also had my Z too high on that first cut...so this time I had deeper cuts with lower initial Z so it went a lot deeper into the waste board with a hotter needle. Oh yeah, needle is also getting pretty dull so that doesn't help. Guess I shouldn't be too surprised parts stuck to the waste board with all that!
 

dkj4linux

Elite member
Me, too... I watched the whole video, Jason. Not without hiccups, it was very gratifying to see the 2nd and 3rd sheets cut without issue. I see and want the vacuum table capability but I'm still having a hard time bringing myself to fire up all that noisy stuff. ;)

Mark, I was married for over 44 years to a true hoarder... and I was/am a serious packrat. Between us, I could have never built enough shelves, closets, storage sheds, and/or buildings to store the sheer mass of stuff we've gathered over the years. And, about 10 years ago, when she and I separated ourselves into my two houses (I inherited my grandparents old farmhouse 100 yards or so away from the house I built in 1981...and it had already been filled, literally to the ceiling, with primarily her "stuff"), I really just had a couple of rooms to live in. Very frustrated and demoralized, I've never been able to bring myself to get organized, so I've been living in clutter and moving about through "trails", which are in continual need of clearing. But I've continued to do the "fun stuff" I love, building/developing machines... to the point my 14' x 16' living/work space eventually consisted of just a recliner, a large screen TV, a mountain of tools, and surrounded by 9 different machines -- various 3d printers, CNC needle cutters, laser engravers, camera sliders, etc. -- all either completely built and/or undergoing construction... and all in the same small room. I didn't have any place to put them and it was getting to where I couldn't move at all! Absolute, total, frustration.

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Meanwhile, my wife passed away about 18 months ago... and my daughter and her family, who had been living with her the last year or so of her life, have since cleaned and remodeled my house. And, now he's taken a job in San Antonio... it's a great opportunity for him. I really hated to see them go but they, of course, need to do what's best for them and their future. So, here I am... rattling around in my nice, clean house and somewhat lost! But I am determined to not let this house get cluttered up like the other one... so I am taking my time and trying to insure I have a place for everything that I bring in. I want to keep the rest of the house "presentable" so that when the kids/grandkids come, they'll have a place to stay.

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I've chosen my grandson's bedroom to be my new workroom. Tardis on the wall (did I mention my SIL is a graphic artist?) and a hardwood floor, it "spoke" to me more than the girls' rooms. I want to get a couple more of the large wire shelving units and I think I'll be able to get everything I need in there. As I said, I'm in no hurry and want to insure everything has it's place before I bring it in...

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Anyway, it'll take time to adjust to my new situation and get set up to start working again. I'm now thinking a LowRider is in my future and I should be able to get started printing parts before long. The new C-beam machine is also completely built and once I find a home for it, I should be able to use it to cut a few of the plates I'll need for the LowRider... and, eventually, your nifty foam cutter machine ;)

Enough! -- David
 
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jhitesma

Some guy in the desert
Mentor
I hope you have better luck than I have at staying uncluttered :( I was so happy last May after spending a full weekend completely emptying my office and turning it into my shop - mostly to make room for the 3'x4' MPCNC. It was so neat to be able to have 3 adults in there at once working on a project and not feel cramped! I could even sit in my old green armchair again for the first time in 6 years, I was loving it!

But...a year later and it's cramped in there again :( A big part of it is raw materials that I haven't had a good place to stack. And a couple of boxes of electronics gear under the MPCNC that I haven't had time to sort through yet (filling the space I had planned on using to storing raw materials.) My desk is lost under piles again...even though I've cleaned it three times in the past year...but after 40 some years I've come to accept that a clear desk is something that I will never posses for more than a few hours...a day or two if I'm unlucky and don't have time to work on any projects :D

I'm really thinking about getting rid of my large format plotter so I can put some kind of bench/shelves/cabinet there instead to help organize...I haven't used the plotter in almost 2 years now and I'm sure the ink has dried up so it will be a big production to clean it up and get it going. I only needed it for printing plans and now that I have the MPCNC I really don't need it. But I hate to see it go in the trash and doubt I can find anyone who wants it. I'd put it off into storage - but don't have anywhere I can put it. One of these days I'll probably just get frustrated and pull it out and be done with it...but for now I can't quite bring myself to let it go.


I'm still not sure what happened the first few times I tried cutting that first sheet. You saw the first go in the video, but there were 2-3 more equally failed attempts. What's most perplexing is when it did finally work it was with the exact same gcode. The only thing different is I didn't turn on the camera...but I've had the camera mounted there quite a few times before with no issues so don't think it causes any interference. All I can figure is the machine had performance anxiety!