1mx1m hot plate?

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cozmicray
A large griddle

[www.ebay.co.uk]

After a print session you could do pancakes and bacon for the whole neighborhood.

But at 3Kw you may have to notify power supplier to put a couple more reactors on line?

Perhaps a steel tooling plate with many small tubes constructed in it.
A large boiler could pump in superheated steam --- the exit steam could be router to heat your house.

Perhaps a visit to the GE 3D printing development facility.
[www.ge.com].

3kw only?
silly me, my heated silicone pad goes to about 8kw.

Maybe they will let you comb thru the "surplus" area

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rowow
Ive already researched into these, and as you see yourself 500$ is way too much for me.

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dc42
IMO you cannot build a large 3D printer on a budget. The only way I know of getting a sufficiently flat bed of that size is to use an aluminium tool plate. To heat it, I would ask these people [www.aliexpress.com] to quote for a silicone heater slightly less than 1m square. They did a custom heater for my delta printer at a very good price, so I would expect it to cost a lot less than the $450 that has been mentioned.

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val c.

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rowow
Ive already researched into these, and as you see yourself 500$ is way too much for me.

rowow, you might want to look past the value of the money. when all is said and done, all the time you have to research and try new methods to heat up that large surface, not to mention possible failures and setbacks, I think it't not worth it.
for the 450 usd you pay, you get a stable product, etched foil (not wire) and also in any configuration you wish, all the way to your door, nicely round packed so as not to bend. no more oven resistors, surface applied resistors or camp fires under the heated bed.
all you have to do is unwrap the thing, put it on your platform, put the glass on top and voila, you're in business.
you have to decide if you want to be wandering more on the tinkering side versus getting your project done and working properly.
as they say, some things money can't buy.

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Paul Wanamaker
I'm going to post here, only because this topic will be found and read by others, and they deserve good information.

I am however very very disappointed in the tone of this thread, it's almost a shame to post in it. The members that have given the most of their time here are some of the most respected and experienced. Their advice has been very good. Guys, you have my highest regard, thank you. You have a lot of patience.

What does it take to heat a bed of 1m size?: this has already been discussed, I will just add some insights from my own experience:

There was a heated bed referenced earlier in this thread on Grassrootsengineering.
For reference that one has a 403x403 build area, sightly thinner material for the bed than mine, and a 480 watt heater. (BTW, he estimates it would take $3000 to $5000 to build that printer, and you can get his plans for $99 - it does cost something for engineering.)

Also for reference, my printer is a Delta with an unusually shaped build plate, the longest dimension across being 431mm. It's roughly similar in size as the above, a bit smaller, but thicker.
It is made of cast aluminum tooling plate - 9.51mm thick (I got the plate as a rem for $40, about 1/2 price), and I use a sheet of mirror glass on top as a print surface.
Due to the unusual shape of the bed, used twelve - 50w power resistors. In parallel these have 8.33 ohms. With my custom 64.5v DC power supply, at 7.74A, this puts out 500W of heat. I didn't want to use mains power there, and I do use a hardware thermostat too for safety, but that's just me... being safe.

- Un-insulated it used to take about 40-45 minutes to reach 109C, using 500 watts, with an enclosed and insulated build chamber.
- After I fully insulated around the bottom of the build plate it now takes 25 minutes. The uninsulated plate referenced on Grassrootsengineering is perhaps slightly larger, I estimate will take that somewhere near 30 minutes to come up to temp, give or take 5 minutes. Someone could ask him to be sure, but I'm estimating here.

Requirements for a build plate?
A build plate needs to be extremely flat over the entire surface in order for the first layer to stick properly, and the print must also be even enough for the following layers to be smooth.
In my experience a difference of .1mm is too much variation, I shoot for .02mm. Your tolerance will vary somewhat depending on the first layer thickness used, and if a raft is used. You must define your tolerance, and engineer to make that happen.

Cast aluminum tooling plate is nearly flat enough.
- For thicknesses over .5 inch it has a tolerance (converted to metric) of 0.416mm per meter, and will weigh 78lbs or 35.38 kg for .5 inch, and will deflect several mm just under it's own weight, since it can not be securely constrained at the outside edges.
- The tolerance is worse for less than .5 inch thickness for cast tooling plate: 1.25 mm per meter tolerance, and will deflect more.
- So clearly a machine of this size machine must be firmly mounted (not on rollers, on carpet, etc), with an adjustable mount for the build plate so it can be trued up.

Regular aluminum plate is not recommended. Why?
- The flatness tolerance starts out worse (over 2.5mm per meter), and the internal stresses cause it to warp when heated and cooled. This does not happen with cast tooling plate.

How thick does the plate need to be? An engineer could specify more exactly, and there is a much better thread here where support methods are discussed. I think near .5 inch, and will need to be supported in the middle, and the supports need to be adjustable to true the plate.

Mirror glass is flat enough, but as stated is a very poor heat conductor, and would need to be thicker than usual for that large dimension, making it even worse. I'm not sure mirror glass is obtainable in the thickness required. Regular glass is not required to be as flat, and others have seen here that it isn't always flat enough.
Because of the poor heat conduction, there would need to be some form of heat spreader, or put more heaters close together. If you use a regular aluminum plate as the heat spreader then it has to be flat and not warp - hence a cast plate, or multiple smaller heat spreaders bonded to the glass. This could make it more of a challenge to support the glass in a perfectly flat/adjustable way, and would cause it to expand unevenly. I haven't seen it done, but there's always a first time. It would be a shame if something dropped on it and it cracked tho, and I would expect it could crack if some of the heaters failed or were not used.

How much More for 1 meter square?
The referenced build area was 162,409 square mm, a one meter square bed is 6.15 times as large.
However I estimate the build plate also needs to be between 50 and 100% thicker in order to stay flat at that size, and this extra thermal mass has to be taken in to consideration for the preheat time - as stated you are heating a mass, not air, or just a wire.

In the thread below they estimated they needed a 2500 watt custom silicone heater for their 45 lb, 1 meter build plate (preheat time not tested, that printer is still not finished as of this date).

Just based on the increase in area: 480 watts x 6.15 = 3130 watts.
I estimate it would actually take close to an hour+ to reach over 100C as the bed must be thicker unless more power is used (more thermal mass, more convection and radiant losses). I can tell you, that's a painfully long time. Insulation placed on the top could speed this up some. It must definitely be insulated below.

That's also an awfully lot of power use, and a lot heat being generated. The heat from the printer will need to be exhausted outdoors, unless you plan on heating the room with it (not recommended - ABS fumes = toxic). That's a change from the usual, the build chamber will need to be cooled, not heated.

As has been stated you also need to account for the deflection of the frame, gantry, etc. for the weight and forces to be applied.
This was best discussed in this thread: 1 Meter Bot Project.
They didn't use cast plate there for their build plate, and didn't support it properly, so I think they will have problems - if they ever finish it.

To others that are considering building a very very large printer, my humble advice:
- Make sure the products you are going to make with your monster are worth the 10x to 30x investment in time and materials that a printer of this magnitude will take over a smaller sized printer.
- Read about all the other large printer builds
- Learn all you can, read the entire site in fact. The more you learn, and experiment, the more you will find you still don't know. It can be very humbling, but illuminating to find out you were wrong.
- Take the good Dr's advice.
- Then build at least one normal sized printer from scratch. Then you can use that printer to make parts for the bigger one, and will have gained invaluable experience (anyone want to buy a really nicely tricked out, used Rumba... just kidding.).

No one here has successfully created a printer of 1 M size that will print its whole volume, yet, despite some considerable effort. There have been a couple pictured with some large prints, but not near their entire volume.

We're pulling for anyone that wants to try, someone's going to do it.

We'd sure like to know how it turns out for you.

P.S.
I think the good Dr is right, for a printer this size - a bed of the special (but not expensive) foam is more practical. That's one of the reasons the really big printer manufacturers use it. He's found an easily sourced alternative, and gone to the trouble of testing it. You've done him and others a great disservice, and should apologize.

P.P.S.
Please post some photos of your other 3D printers, that will help us know where you're coming from.

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val c.

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dc42
IMO you cannot build a large 3D printer on a budget. The only way I know of getting a sufficiently flat bed of that size is to use an aluminium tool plate. To heat it, I would ask these people [www.aliexpress.com] to quote for a silicone heater slightly less than 1m square. They did a custom heater for my delta printer at a very good price, so I would expect it to cost a lot less than the $450 that has been mentioned.

you're right about the budget.
I think I passed 11.000 on mine.
regarding the 450 usd, that was for a 1275 x 1110 mm etched foil silicone pad (there is a picture of it in one of my previous posts on this thread). I don't know the size of your heater, but as you say, Aliexpress can have some darn good deals sometimes. Considering I got a quote from durex of about 2000 doillars for the same thing, I believe I still came out ok with only 450 usd from china.

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rowow

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val c.

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rowow
Ive already researched into these, and as you see yourself 500$ is way too much for me.

rowow, you might want to look past the value of the money. when all is said and done, all the time you have to research and try new methods to heat up that large surface, not to mention possible failures and setbacks, I think it't not worth it.
for the 450 usd you pay, you get a stable product, etched foil (not wire) and also in any configuration you wish, all the way to your door, nicely round packed so as not to bend. no more oven resistors, surface applied resistors or camp fires under the heated bed.
all you have to do is unwrap the thing, put it on your platform, put the glass on top and voila, you're in business.
you have to decide if you want to be wandering more on the tinkering side versus getting your project done and working properly.
as they say, some things money can't buy.

I do have to agree with how much time it will save me, but for 500$ that is slightly more then a whole week of work. And another reason I forgot to mention on why I want this to be so cheap is because I plan on helping others on building a cheap 3d printer as I have too many friends and family who complain 3d printing is too expensive, and I want to throw it all in the dump that with some elbow grease you can build a machine that's worth a car for a few hundredth dollars, something that anyone can do.

I actually just finished filming part 1 of X axis, yeah, there is so much to go through that it takes one whole video per axis, but ill merge the Y and Z axis videos together as they are one whole system.
But like I said, I got everything thought out except for the damn heat bed, ill experiment with nicrome, and if im unlucky and it doesnt work, ill go with silicone pads. But again, I dont want to spend more then half of my machine budget on the heating pad

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val c.

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rowow

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val c.

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rowow
Ive already researched into these, and as you see yourself 500$ is way too much for me.

rowow, you might want to look past the value of the money. when all is said and done, all the time you have to research and try new methods to heat up that large surface, not to mention possible failures and setbacks, I think it't not worth it.
for the 450 usd you pay, you get a stable product, etched foil (not wire) and also in any configuration you wish, all the way to your door, nicely round packed so as not to bend. no more oven resistors, surface applied resistors or camp fires under the heated bed.
all you have to do is unwrap the thing, put it on your platform, put the glass on top and voila, you're in business.
you have to decide if you want to be wandering more on the tinkering side versus getting your project done and working properly.
as they say, some things money can't buy.

I do have to agree with how much time it will save me, but for 500$ that is slightly more then a whole week of work. And another reason I forgot to mention on why I want this to be so cheap is because I plan on helping others on building a cheap 3d printer as I have too many friends and family who complain 3d printing is too expensive, and I want to throw it all in the dump that with some elbow grease you can build a machine that's worth a car for a few hundredth dollars, something that anyone can do.



I actually just finished filming part 1 of X axis, yeah, there is so much to go through that it takes one whole video per axis, but ill merge the Y and Z axis videos together as they are one whole system.
But like I said, I got everything thought out except for the damn heat bed, ill experiment with nicrome, and if im unlucky and it doesnt work, ill go with silicone pads. But again, I dont want to spend more then half of my machine budget on the heating pad

I don't want to rain on your parade, but I don't think nicrome wire will work so well. thinking about it, you only have so much contact between the wire and the surface to be heated (aluminum in your case). think of a tube sitting horizontal on a flat surface: the contact area is the generator line of the cylinder that comes in contact with the surface. conversely, that's how heating wires work, and the heat transfer is not very efficient. have a look at etched foil, for comparison.
I have not tried the nicrome wire method myself (back in the day) but I have a friend who went that way, and I witnessed pretty much all the steps he took into that direction. he gave up eventually, and now he's working on a metal clad, surface mounted resistors solution.
not trying to be snotty, just trying to save you some valuable time by avoiding unwarranted pioneering work.
your approach, altruistic as it may be, should not loose sight of the more technical aspects of such an endeavor. a silicone pad has the immense advantage of distributing heat evenly, and i'm talking here about silicone pad as an approach to the problem.
another way for you might be to buy several smaller pads and use them together.
also, looking forward to seeing the videos of your x and y axis.

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LarsK
It would be nice if you two could post some pictures of where you are in the build process. Very interesting to see.

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rowow
Wow, thanks PulsedMedia! actual advice and help!

And have you heard of v slotted aluminum extrusions? I dont know how much you got your 22mm rods but a 1.5m stick from openbuilds costed me $15. Plus they are modular and really strong, so no 3d printed parts for the corners. The most expensive part is the wheels though, they cost 80$ for a set of 20, and you need 4 for each rail system.
But there is a supplier in Europe too last time I researched for cheap linear rails, google v slot linear rails and you could get a supplier there.
[openbuildspartstore.com]

And with your heated bed did the nicrome wire work or are you still building it? Because I have some worries with nichrome, so if it worked with you that will give me alot of motivation into further funding the nicrome idea.
For the PIR foam idea ill use it to test the 3d printer in my room (as I dont want a 2kw heater in my room) but otherwise when I move I still want to go with a heated bed as it will be cheaper for me if I can get a heating system for a few hundredth dollars.

But great to met you! finally someone with a similar goal as me.

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PulsedMedia
80mm pulley with 1/8 steps would give 50micron positional resolution @ max speed of 1600mm/sec. That's still 10s+ to go from end to end ...

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o_lampe

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PulsedMedia
80mm pulley with 1/8 steps would give 50micron positional resolution @ max speed of 1600mm/sec. That's still 10s+ to go from end to end ...

So your printer is 16meters long?! 1600mm/s *10s = 16m

Just kidding, I love your pragmatic approach, although I'd do the heating differently.
-Olaf

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rowow
When I first started 3d printing I wanted to go with dc motors and encoders but never was able to do so as there was no help online and I have no coding ability. But that was a year ago, so if your able to control linear movement with a dc motor please keep me updated! I really wanted to do so as all printers that I disassembled did the same, but I couldn't find any help online.

But currently im using 2amp nema 17 84oz.inch stepper motors with drv8825 drivers (2.5amp) Which are twice the strength of a usual stepper motor on a reprap, and therefore I can increase the speed with some larger pullies