Aluminum Sheet Between Heater and Glass
Posted by Shachar85
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Re: Aluminum Sheet Between Heater and Glass November 22, 2015 08:59PM |
Many printers have large beds and don't use special bed
I would use:
base plate --- silicone insulator --- heater --- thin aluminum -- glass.
ie: Aluminatus TrinityOne
[www.3ders.org]
Print Bed:
The Aluminatus TrinityOne ships by default with a true Borosilicate print surface as well as a kapton heating element that allows for printing of PLA, ABS , resins and other types of plastic.
The print surface has a 290mm x 290mm 24V, 200W kapton heater installed under a 300mm x 300mm aluminum heat spreader. The entire assembly is supported by a G10 and Aluminum Y platform machined for a light-weight and rigid/aligned print platform that hardly needs to be leveled.
I would use:
base plate --- silicone insulator --- heater --- thin aluminum -- glass.
ie: Aluminatus TrinityOne
[www.3ders.org]
Print Bed:
The Aluminatus TrinityOne ships by default with a true Borosilicate print surface as well as a kapton heating element that allows for printing of PLA, ABS , resins and other types of plastic.
The print surface has a 290mm x 290mm 24V, 200W kapton heater installed under a 300mm x 300mm aluminum heat spreader. The entire assembly is supported by a G10 and Aluminum Y platform machined for a light-weight and rigid/aligned print platform that hardly needs to be leveled.
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Re: Aluminum Sheet Between Heater and Glass November 22, 2015 09:52PM |
I don't get it. Everyone knows you need a flat surface to print reliably, yet so many keep buying thin, flexible aluminum and then put glass on top of it. Why do people keep buying the thin, flexible aluminum? It makes no sense. Why not just get a flat aluminum plate such as cast tooling plate in the first place and be done with it? Unlike galss, aluminum is thermally conductive so the temperature will be even across the surface and you won't have print adhesion problems. Surely the cost of a thin flexible aluminum plate, plus glass to fit, and the goop you're going to have to slather on to get prints to stick can't be much less than the cost of a piece of cast tooling plate. We're talking about a few dollars/euros here, not hundreds. Are the few dollars/euros you save worth all the screwing around to find a magic formula to try to get your prints to stick?
Since you're developing the printer yourself, I advise you to try out a 3 point leveling system. When you level the print bed you're adjusting it so that it lies in the XY plane defined by the printer's guide rails. It takes only three points to define a plane. The typical 4 corner "leveling" system bends the bed plate and the undercarriage. You can't level a bent plate, neither can autoleveling. With enough screwing around you may get the center of the bed flat/level enough to print on but you aren't likely to be able to use the entire bed. The further you get from the center the worse it will get. Auto leveling assumes that the bed is a plane so its not necessarily going to help.
Here's a 250 mm diameter ABS print on my 317 x 305 x 6.35 mm cast tooling plate bed supported by a three point leveling system:
I have never seen anything of similar size done on a thin piece of aluminum with a glass plate and a 4 point leveling system.
What's the point of building a machine with a 200 x 400 mm bed if you can't print on the entire surface? The thin aluminum/glass/4 corner leveling is done in cheapo (and some not so cheap) printers because it is a couple dollars/euros cheaper than doing it the right way, or the "designers" don't know any better. The whole point of developing your own printer is to do something better than you can get elsewhere. If you're just going to copy their mistakes, just get one of those cheapo kits and save yourself a lot of trouble sourcing the parts.
Edited 2 time(s). Last edit at 11/22/2015 10:30PM by the_digital_dentist.
Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]
Since you're developing the printer yourself, I advise you to try out a 3 point leveling system. When you level the print bed you're adjusting it so that it lies in the XY plane defined by the printer's guide rails. It takes only three points to define a plane. The typical 4 corner "leveling" system bends the bed plate and the undercarriage. You can't level a bent plate, neither can autoleveling. With enough screwing around you may get the center of the bed flat/level enough to print on but you aren't likely to be able to use the entire bed. The further you get from the center the worse it will get. Auto leveling assumes that the bed is a plane so its not necessarily going to help.
Here's a 250 mm diameter ABS print on my 317 x 305 x 6.35 mm cast tooling plate bed supported by a three point leveling system:
I have never seen anything of similar size done on a thin piece of aluminum with a glass plate and a 4 point leveling system.
What's the point of building a machine with a 200 x 400 mm bed if you can't print on the entire surface? The thin aluminum/glass/4 corner leveling is done in cheapo (and some not so cheap) printers because it is a couple dollars/euros cheaper than doing it the right way, or the "designers" don't know any better. The whole point of developing your own printer is to do something better than you can get elsewhere. If you're just going to copy their mistakes, just get one of those cheapo kits and save yourself a lot of trouble sourcing the parts.
Edited 2 time(s). Last edit at 11/22/2015 10:30PM by the_digital_dentist.
Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]
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Re: Aluminum Sheet Between Heater and Glass November 23, 2015 06:20PM |
Can you provide link / price for 16 x 9 inch aluminum flat tool plate?
What are the flatness spec on your printer bed?
Tnx
What are the flatness spec on your printer bed?
Tnx
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Re: Aluminum Sheet Between Heater and Glass November 23, 2015 08:48PM |
Very nice!
The Modified MegaMax is marching along in modifications and upgrades
Perhaps Shachar85 should consider PIR (polyisocyanurate) foam print bed?
See:
Alternative Print Bed at [mark.rehorst.com]
Have Phun
The Modified MegaMax is marching along in modifications and upgrades
Perhaps Shachar85 should consider PIR (polyisocyanurate) foam print bed?
See:
Alternative Print Bed at [mark.rehorst.com]
Have Phun
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Re: Aluminum Sheet Between Heater and Glass November 24, 2015 08:27AM |
1/4" extruded aluminum sheet that is 18" wide will be bowed. The metal grains tend to orient themselves along the direction of extrusion, so when it heats it will expand unevenly.
At 18" x 18" the expansion (tooling plate or not) may be a problem depending on how you mount it. You can expect about 1 mm expansion at 3D printing temperatures. If you're putting it into a machine in which the bed moves in the Z axis or not at all, it will be easy to deal with expansion- just put flat magnets on the bottom of the plate to hold it down. In a machine in which the bed moves in the Y axis it will be a little more of a problem to design a mount that controls its movement, levels it, yet allows it to expand.
Here is a picture of a piece of 12" wide x 1/4" thick extruded 6061 aluminum plate that I originally purchased for my printer about 3 years ago, before I knew that tooling plate exists. After I saw the curve in this plate I did what many people do and got myself a piece of glass to print on- hey it was cheap and I didn't know any better! That was a disaster for all the normal reasons- not very flat, uneven heating, etc. Once I learned about tooling plate, I ordered a piece and never looked back. Since then I have been extoling the virtues or cast tooling plate to a mostly deaf audience. It's sad how the small difference in price between a cast plate and everything else can close people's ears.
What you're seeing in this picture is a steel ruler stood on edge across the width of the plate. The gap under the ruler at the center of the plate is about 2 mm. Good luck printing on that!
Ebay is chock full of cast tooling plate cut-offs for very reasonable prices. Here's a shopping tip: if it isn't called "cast tooling plate" or "jig plate", or "MIC-6" or similar descriptive term, you can't count on it being flat.
Here's a 12 x 12" plate for $40 shipped: [www.ebay.com]
Here's a 24 x 24 x 3/8" plate for $160 shipped. [www.ebay.com]
If you're going to build a quality, custom sized printer, you're going to have to put in a little effort (and spend a little money). It took me all of 30 seconds to find those listings.
I've seen people justify their cheapness by saying "the surface of the aluminum is too delicate so it has to be 'protected' with a piece of glass". I think someone in a $300 printer company marketing dept came up with that idea. What happens to glass when you stress it in the way that scratching a piece of aluminum would? It breaks in tiny shards that get into your bearings and if you're lucky, don't cut you during the clean up process. What is the consequence of scratching aluminum? Zero. You're going to put kapton tape, or PEI, or PET tape, or painter's tape on it. The tape covers scratches and they never appear in the print. My bed has several scratches from head crashes, etc. when I was first setting up the machine and controller board. They are of absolutely no consequence.
Then there's the "factory production" argument. "With a glass plate I can take it off the printer and put on a fresh piece of glass and start printing again right away." I print almost daily and have never felt the need to produce prints so fast that I need to swap plates out to print the next part. If you're depending on your printer to earn your living, you'd better invest in multiple printers or step up your marketing program and select your paid print jobs more carefully. You can print $10 doodads all day long and make about $10 by the end of the day or you can print skulls or other body parts that sell for $500 each (or more) for surgical planning. Of course, if you want to do that sort of work, you'll need a very high quality, very reliable printer even to start. The few $ you may save by making your printer look like its capable of large, high quality prints vs the few $ extra you'll spend making it actually capable of large high quality prints can mean the difference between eating instant Ramen and a steak dinner.
Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]
At 18" x 18" the expansion (tooling plate or not) may be a problem depending on how you mount it. You can expect about 1 mm expansion at 3D printing temperatures. If you're putting it into a machine in which the bed moves in the Z axis or not at all, it will be easy to deal with expansion- just put flat magnets on the bottom of the plate to hold it down. In a machine in which the bed moves in the Y axis it will be a little more of a problem to design a mount that controls its movement, levels it, yet allows it to expand.
Here is a picture of a piece of 12" wide x 1/4" thick extruded 6061 aluminum plate that I originally purchased for my printer about 3 years ago, before I knew that tooling plate exists. After I saw the curve in this plate I did what many people do and got myself a piece of glass to print on- hey it was cheap and I didn't know any better! That was a disaster for all the normal reasons- not very flat, uneven heating, etc. Once I learned about tooling plate, I ordered a piece and never looked back. Since then I have been extoling the virtues or cast tooling plate to a mostly deaf audience. It's sad how the small difference in price between a cast plate and everything else can close people's ears.
What you're seeing in this picture is a steel ruler stood on edge across the width of the plate. The gap under the ruler at the center of the plate is about 2 mm. Good luck printing on that!
Ebay is chock full of cast tooling plate cut-offs for very reasonable prices. Here's a shopping tip: if it isn't called "cast tooling plate" or "jig plate", or "MIC-6" or similar descriptive term, you can't count on it being flat.
Here's a 12 x 12" plate for $40 shipped: [www.ebay.com]
Here's a 24 x 24 x 3/8" plate for $160 shipped. [www.ebay.com]
If you're going to build a quality, custom sized printer, you're going to have to put in a little effort (and spend a little money). It took me all of 30 seconds to find those listings.
I've seen people justify their cheapness by saying "the surface of the aluminum is too delicate so it has to be 'protected' with a piece of glass". I think someone in a $300 printer company marketing dept came up with that idea. What happens to glass when you stress it in the way that scratching a piece of aluminum would? It breaks in tiny shards that get into your bearings and if you're lucky, don't cut you during the clean up process. What is the consequence of scratching aluminum? Zero. You're going to put kapton tape, or PEI, or PET tape, or painter's tape on it. The tape covers scratches and they never appear in the print. My bed has several scratches from head crashes, etc. when I was first setting up the machine and controller board. They are of absolutely no consequence.
Then there's the "factory production" argument. "With a glass plate I can take it off the printer and put on a fresh piece of glass and start printing again right away." I print almost daily and have never felt the need to produce prints so fast that I need to swap plates out to print the next part. If you're depending on your printer to earn your living, you'd better invest in multiple printers or step up your marketing program and select your paid print jobs more carefully. You can print $10 doodads all day long and make about $10 by the end of the day or you can print skulls or other body parts that sell for $500 each (or more) for surgical planning. Of course, if you want to do that sort of work, you'll need a very high quality, very reliable printer even to start. The few $ you may save by making your printer look like its capable of large, high quality prints vs the few $ extra you'll spend making it actually capable of large high quality prints can mean the difference between eating instant Ramen and a steak dinner.
Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]
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Re: Aluminum Sheet Between Heater and Glass November 24, 2015 08:16PM |
If I bought a plate or some PIR for you
Would the Canadian Mounties track me down?
or
track you down for accepting contraband 3D printing material?
Would the Canadian Mounties track me down?
or
track you down for accepting contraband 3D printing material?
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Re: Aluminum Sheet Between Heater and Glass December 26, 2015 06:39AM |
It might be the case, but I have tried searching by the 3 different terms you list here without any hits at all.Quote
the_digital_dentist
Quote
dintid
Also: I can't find any such things in Europe.
Cast tooling plate is a raw material for any and every machine shop on the planet. I'm certain there are at least a few thousand machine shops scattered around Europe. If you can't find cast tooling plate it may be because it's called something else, but it's there and it's available.
I try to use Trading sites like ebay, amazon etc due to buyers protection, so I do not just Google.
"cast aluminum tooling plate", "cast jig plate", etc....MIC-6"
Instead of being derogotary, try giving direct links or explain in plain terms what it is you mean. You could be helping a lot of people out by spreading the Word instead of defaming everyone for not doing it the same as you,
Thanks.Quote
dc42
See EcoCast here [www.aluminiumwarehouse.co.uk].
I have some plain glass as well.. I do like to being able to dump the glass into the freezer though, which isn't a good idea with plain glass from 100cQuote
dc42
So do I. But I use an aluminium heat spreader between the heater and the glass, so that I can use ordinary float glass instead of borosilicate.
Edited 1 time(s). Last edit at 12/26/2015 06:41AM by dintid.
My Instructables - both total newbie instructables and some for intermediate users.
My Designs on Thingiverse
YouTube channel containing a few 3D printing videos - they are videos for my Instructables, and mostly not standalone.
Ultius / Tantillus Thingiverse Group
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Re: Aluminum Sheet Between Heater and Glass January 07, 2016 06:57AM |
I'm sold on the cast alu plate, but it is tricky here in the UK, ebay are skewing results for sure, maybe they dont want us to have the manufacturing good stuff here in the UK, for fear of what we'll make with it. I'm waiting to hear from a US supplier about shipping, if I get the 6mm plate (220mmx220ish) I'm wondering will I have to redesign the bed from belt to leadscrew due to the weight or will the belt handle it, wondering about judders, though plan on keeping the speed down.
thinking of using this for the leveling
Edited 1 time(s). Last edit at 01/07/2016 06:59AM by MechaBits.
thinking of using this for the leveling
Edited 1 time(s). Last edit at 01/07/2016 06:59AM by MechaBits.
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Re: Aluminum Sheet Between Heater and Glass January 07, 2016 07:49AM |
I tried that site yesterday(spotted your earlier link), but didnt use the tool to find item and nothing came up in the search, just did it again and used the quote tool, nice price only about 10-13 quid for 6 or 8mm, it'll probably get here before I get a reply from the US supplier
Yes I think I'm going to use http://www.aluminiumwarehouse.co.uk/cutting_calc.php
now to decide 6mm 8 or 10, I'm thinking 6 is fine for this smaller setup.
Cheers!
Edited 1 time(s). Last edit at 01/07/2016 07:57AM by MechaBits.
Yes I think I'm going to use http://www.aluminiumwarehouse.co.uk/cutting_calc.php
now to decide 6mm 8 or 10, I'm thinking 6 is fine for this smaller setup.
Cheers!
Edited 1 time(s). Last edit at 01/07/2016 07:57AM by MechaBits.
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Re: Aluminum Sheet Between Heater and Glass January 07, 2016 08:28AM |
Quote
MechaBits
thinking of using this for the leveling
Depending on how that device is made, it might be very good. Assuming it is well made (no play in the top plate regardless of screw settings) I can see three potential problems. If your bed moves in the Y axis, the small base will allow it to flop a little back and forth every time it starts/stops unless you set acceleration/jerk very low, especially if you have it riding on sloppy bearings on end-supported guide rails. The second problem is reaching those adjustment screws under the bed. Neither is a problem if the bed only moves in the Z axis. The third problem is how to attach that device to the bed if you are using a heater on the underside of the bed.
If the bed moves in the Y axis and you use a fully supported linear guide, that device might work quite well. I am using two small linear guides in my printer's Y axis and have been considering the possibility of rebuilding it with a single, larger guide and either one or two bearing blocks. Supporting a heated bed from its center eliminates bowing of the bed when heated because of the expansion of the bed plate against widely spaced support/leveling screws.
The closer the level adjustment screws are to the center of the bed, the more the adjustments get magnified at the edges of the bed. It will take only tiny adjustments of the screws to tilt the bed and you may find it tricky to get the level set just right.
If you're building a new printer and plan to print on a heated bed you can leave out any sort of mechanical bed leveling system and use autotramming. If you print on a sacrificial foam bed, you can leave out mechanical leveling, autotramming, and a bed heater, and use a smaller power supply.
Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]
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Re: Aluminum Sheet Between Heater and Glass January 07, 2016 09:35AM |
Thanks DD for reminding me of a few of the issues,
"Assuming it is well made - looks ok and is designed to keep camera steady but yes it might have a few quirks of its own, (no play in the top plate regardless of screw settings) "
screw pitch might cause some issues, vibrations could make them loosen.
3 potential problems.
"If your bed moves in the Y axis, the small base will allow it to flop a little back and forth every time it starts/stops unless you set acceleration/jerk very low, "
yes I have thought about this one, it does concern me, currently testing a few configurations but waiting for more parts too, as my Y axis bed will be supported by a single flat bar (25mm) but with plate or leveler, or 15mm tube with leveler, joining the 2 bearings the tilt of the those short bearing is one area that i can hopefully solve with the longer 12mm bearings but maybe it wont be enough? At the moment I'm hoping to have the joining bar in line with the rails, but I have 2 other positions, underslung & above the rails, each with its own pro's n cons.
"The second problem is reaching those adjustment screws under the bed. "
Currently the whole bed assembly can be moved and access to the underneath is quite easy, but I am worried about single screws for fixing anything especially without some anti rotation pins, though the base of the leveler looks like I could add a few more holes in the pockets.
"The third problem is how to attach that device to the bed if you are using a heater on the underside of the bed.
The closer the level adjustment screws are to the center of the bed, the more the adjustments get magnified at the edges of the bed. It will take only tiny adjustments of the screws to tilt the bed and you may find it tricky to get the level set just right."
Yeah one pivotal screw again, which I think the heatbed has a hole in center, but I always wondered why!
as some of these heatbed plates say you can print on top of it, but yet there is a hole in center, maybe squirting a little molten filament in there helps with traction? But I plan to add a silicon sheet, heatplate, then tool plate,
but will have to drill n tap the underside, but if Im going to do that for one hole, I might as well do a few more at the extremities, and get a more precise leveling mechanism. I've also been thinking about replacing springs, with repelling magnets, but that might be too bouncy or cause other issues, but i still want to play with the idea in a form similar to the leveler above, should be fun.
"If the bed moves in the Y axis and you use a fully supported linear guide, that device might work quite well. Supporting a heated bed from its center eliminates bowing of the bed when heated because of the expansion of the bed plate against widely spaced support/leveling screws."
The fact that it has a fairly large diameter should provide enough support for the plate, pity the pads weren't silicone as they will melt the rubber pads, I'm not using fully supported in this build but other options are being considered, and as you know, even if the part does get used in one iteration, there is always another use for most of the items that make up my printer.
The next comparable leveler with almost identical design is £50-120, maybe there are some cheaper ones on theodoliites or something, but it's not a complicated device to replicate. I've just ordered a few parts to make my own leveling feet some 6mm grubscrews & nuts, dome nuts for feet, I considered spikes, but at the moment its freestanding on some rubber, maybe it'll get bolted down when finished but I'm trying to keep free at the moment.
The pic shows the bed support at the highest above the rails but hope to take it down 30mm or so, but this is not final config', it's evolved a little since this pic.
"If you're building a new printer and plan to print on a heated bed you can leave out any sort of mechanical bed leveling system and use autotramming. If you print on a sacrificial foam bed, you can leave out mechanical leveling, autotramming, and a bed heater, and use a smaller power supply."
I've not got that far yet, but it sounds like a good place to start, I bless this printer with a sacrifice!
If I get 500mm rails I can probably incorporate the leveling screws directly into the crab clamps which may also be the best way for me to go, cuts out the need for quite a few of my current components, but a 1m belt might not be advisable?
Edited 9 time(s). Last edit at 01/08/2016 02:02PM by MechaBits.
"Assuming it is well made - looks ok and is designed to keep camera steady but yes it might have a few quirks of its own, (no play in the top plate regardless of screw settings) "
screw pitch might cause some issues, vibrations could make them loosen.
3 potential problems.
"If your bed moves in the Y axis, the small base will allow it to flop a little back and forth every time it starts/stops unless you set acceleration/jerk very low, "
yes I have thought about this one, it does concern me, currently testing a few configurations but waiting for more parts too, as my Y axis bed will be supported by a single flat bar (25mm) but with plate or leveler, or 15mm tube with leveler, joining the 2 bearings the tilt of the those short bearing is one area that i can hopefully solve with the longer 12mm bearings but maybe it wont be enough? At the moment I'm hoping to have the joining bar in line with the rails, but I have 2 other positions, underslung & above the rails, each with its own pro's n cons.
"The second problem is reaching those adjustment screws under the bed. "
Currently the whole bed assembly can be moved and access to the underneath is quite easy, but I am worried about single screws for fixing anything especially without some anti rotation pins, though the base of the leveler looks like I could add a few more holes in the pockets.
"The third problem is how to attach that device to the bed if you are using a heater on the underside of the bed.
The closer the level adjustment screws are to the center of the bed, the more the adjustments get magnified at the edges of the bed. It will take only tiny adjustments of the screws to tilt the bed and you may find it tricky to get the level set just right."
Yeah one pivotal screw again, which I think the heatbed has a hole in center, but I always wondered why!
as some of these heatbed plates say you can print on top of it, but yet there is a hole in center, maybe squirting a little molten filament in there helps with traction? But I plan to add a silicon sheet, heatplate, then tool plate,
but will have to drill n tap the underside, but if Im going to do that for one hole, I might as well do a few more at the extremities, and get a more precise leveling mechanism. I've also been thinking about replacing springs, with repelling magnets, but that might be too bouncy or cause other issues, but i still want to play with the idea in a form similar to the leveler above, should be fun.
"If the bed moves in the Y axis and you use a fully supported linear guide, that device might work quite well. Supporting a heated bed from its center eliminates bowing of the bed when heated because of the expansion of the bed plate against widely spaced support/leveling screws."
The fact that it has a fairly large diameter should provide enough support for the plate, pity the pads weren't silicone as they will melt the rubber pads, I'm not using fully supported in this build but other options are being considered, and as you know, even if the part does get used in one iteration, there is always another use for most of the items that make up my printer.
The next comparable leveler with almost identical design is £50-120, maybe there are some cheaper ones on theodoliites or something, but it's not a complicated device to replicate. I've just ordered a few parts to make my own leveling feet some 6mm grubscrews & nuts, dome nuts for feet, I considered spikes, but at the moment its freestanding on some rubber, maybe it'll get bolted down when finished but I'm trying to keep free at the moment.
The pic shows the bed support at the highest above the rails but hope to take it down 30mm or so, but this is not final config', it's evolved a little since this pic.
"If you're building a new printer and plan to print on a heated bed you can leave out any sort of mechanical bed leveling system and use autotramming. If you print on a sacrificial foam bed, you can leave out mechanical leveling, autotramming, and a bed heater, and use a smaller power supply."
I've not got that far yet, but it sounds like a good place to start, I bless this printer with a sacrifice!
If I get 500mm rails I can probably incorporate the leveling screws directly into the crab clamps which may also be the best way for me to go, cuts out the need for quite a few of my current components, but a 1m belt might not be advisable?
Edited 9 time(s). Last edit at 01/08/2016 02:02PM by MechaBits.
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