What type of bed spring should I get?

I am very new to 3D printing and plan to use springs on my Smartrap. What would be the best kind to get for my bed?

the strongest you can find, and that fit around your bed screws!

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victorjung
the strongest you can find, and that fit around your bed screws!

That's super vauge and obvious!

yes i know, but there is nothing more than that you should worry about

I guess your right, I ordered some that looked strong and fit and I'll see how they do

Pressa clothes pegs from Ikea have perfect springs.

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[3DKarma.com] - suppliers of quality, affordable 3D printer kits and filament for the UK market.

The best spring to get is a design that doesn't use springs.

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tjb1
The best spring to get is a design that doesn't use springs.

could you suggest some? Cause I don't remember to have seen any?

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victorjung

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tjb1
The best spring to get is a design that doesn't use springs.

could you suggest some? Cause I don't remember to have seen any?

It means hard mount the bed...nuts, washer, spacers..anything but springs.

You can see my last solution for this in attach.
Plastic dist get less heat down to aliminium support
Easy to adjust height of bed, just loosen the 2 nuts and adjust
Springs seems no point for me. You still have to adjust height proper. No value added with springs .....

Ha det gött
Bosse

Edited 1 time(s). Last edit at 06/30/2014 05:07PM by sidhabo.

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Prusa i3 Reworked, Delivered March 28 2014, RAMPS 1.4
Göteborg, Sweden

The value of having springs is saving your bed if your hot end crashes into it. With springs = bed moves down and no damage done. Without springs = cracked glass / groove dug into the bed / damaged hot end. The end stop should stop the latter happening, but mistakes are known to happen.

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[3DKarma.com] - suppliers of quality, affordable 3D printer kits and filament for the UK market.

As someone who destroyed a hot end nozzle by crashing it into an unsprung bed I can attest to the value of springs! I don't feel they need to be that strong (I'm using 4 from pulled apart pens) as the downwards pressure from the hot end should be very small if the z-stop is calibrated correctly. I have way more problems from thermal expansion of the bed than I ever do from the springs not being adjusted correctly... And that's mostly from impatience trying to print before the whole frame/heatbed/glass has got to a thermal equilibrium.

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3dkarma
The value of having springs is saving your bed if your hot end crashes into it. With springs = bed moves down and no damage done. Without springs = cracked glass / groove dug into the bed / damaged hot end. The end stop should stop the latter happening, but mistakes are known to happen.

No, this concept is enirely wrong. TURN DOWN YOUR Z DRIVER, you do not require that power.

As the person said above, "the strongest you can find, and that fit around your bed screws! ". Now can you tell me why someone would suggest "the strongest you can find"?? Because the bed moves when attached with springs, it wobbles and floats...maybe not up and down, but side to side and forward and back. This is solved by using very strong springs which negate the point of using them.

If you want to make good prints hard mount your bed and turn down your Z axis, they require almost no power on a cartesian because the Z axis does almost nothing.

If you are just printing for fun, do whatever you want...I don't care. Springs are not the way forward, ask anyone with experience.

Edited 1 time(s). Last edit at 07/01/2014 07:57AM by tjb1.

My Prusa actually has like failsafe if Z motor feed and hot head hit the glass. The nuts in X axis end mounts just disengage when the X axis assy is lifted off them.
I did NOT warm the nuts into the plastic mounts.
Drawback is you need to readjust Z level if this happens. Since you might not get the nuts in exactly same height when you get them back into mounts.
Still that saved my glass already a couple of times
Ha det gött
Bosse

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Prusa i3 Reworked, Delivered March 28 2014, RAMPS 1.4
Göteborg, Sweden

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tjb1

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3dkarma
The value of having springs is saving your bed if your hot end crashes into it. With springs = bed moves down and no damage done. Without springs = cracked glass / groove dug into the bed / damaged hot end. The end stop should stop the latter happening, but mistakes are known to happen.

No, this concept is enirely wrong. TURN DOWN YOUR Z DRIVER, you do not require that power.

As the person said above, "the strongest you can find, and that fit around your bed screws! ". Now can you tell me why someone would suggest "the strongest you can find"?? Because the bed moves when attached with springs, it wobbles and floats...maybe not up and down, but side to side and forward and back. This is solved by using very strong springs which negate the point of using them.

If you want to make good prints hard mount your bed and turn down your Z axis, they require almost no power on a cartesian because the Z axis does almost nothing.

If you are just printing for fun, do whatever you want...I don't care. Springs are not the way forward, ask anyone with experience.

Calling it "entirely wrong" is a bit strong. It is a reasonable failsafe, especially for beginners. There are many examples of printer designs, created by people with experience, that use sprung beds. For example, Reprappro, one of the oldest in the business, uses sprung beds. Using strong springs doesn't negate their usefulness - the bed will still move before the hotend causes damage.

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[3DKarma.com] - suppliers of quality, affordable 3D printer kits and filament for the UK market.

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tjb1

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3dkarma
Because the bed moves when attached with springs, it wobbles and floats...maybe not up and down, but side to side and forward and back. This is solved by using very strong springs which negate the point of using them.

It shouldn't wobble and float if the mounting screws are secure and the right size for the holes in the bed. I've got 3mm screws, 3mm holes in the bed, and no lateral movement at all. There's some friction of the screws in the holes so the bed doesn't float up and down as smoothly as it could, but it doesn't need to. It just needs to be easily adjustable, and give enough if a Z disaster happens.

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3dkarma

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tjb1

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3dkarma
The value of having springs is saving your bed if your hot end crashes into it. With springs = bed moves down and no damage done. Without springs = cracked glass / groove dug into the bed / damaged hot end. The end stop should stop the latter happening, but mistakes are known to happen.

No, this concept is enirely wrong. TURN DOWN YOUR Z DRIVER, you do not require that power.

As the person said above, "the strongest you can find, and that fit around your bed screws! ". Now can you tell me why someone would suggest "the strongest you can find"?? Because the bed moves when attached with springs, it wobbles and floats...maybe not up and down, but side to side and forward and back. This is solved by using very strong springs which negate the point of using them.

If you want to make good prints hard mount your bed and turn down your Z axis, they require almost no power on a cartesian because the Z axis does almost nothing.

If you are just printing for fun, do whatever you want...I don't care. Springs are not the way forward, ask anyone with experience.

Calling it "entirely wrong" is a bit strong. It is a reasonable failsafe, especially for beginners. There are many examples of printer designs, created by people with experience, that use sprung beds. For example, Reprappro, one of the oldest in the business, uses sprung beds. Using strong springs doesn't negate their usefulness - the bed will still move before the hotend causes damage.

Being the oldest in the business does not make it right, you would think being this long in the business he would know information required for setup? Take a look at the motors, no amperage rating and no coil diagram(easily figured out though). There was also quite a bit more required information missing on other things but I've not got the time to find them.






Turn your Z drivers down, a cartesian bot does not need Z motors with max current.

Edited 1 time(s). Last edit at 07/02/2014 07:40AM by tjb1.