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What temp are the folks with heated beds running at.I am shooting for 100C. I am running a 75 watt heating pad designed to go on the pan of an engine. Temp comes up slowly and I think I will get to 100C. Right now 16 min into the print I am at 92.

Sounds like you could do with a larger power supply, amp wise.
Mine is a 30 amp supply and it gets the bed to 110 C in a couple minutes.

I have my heated bed running between 130C - 140C because the glass plate for some reason causes a 20C drop in temp, so I get about 110C - 120C on the surface. The bed draws about 4 amps @ 12v and heats up in roughly 15 minutes. The hotter the bed the better the ABS sticks and stays flat (from what I found).

I run mostly PLA, so I rum at 60, glass plate is only causing about 2-5 degrees drop for me.
Most people printing ABS seem to be running >>100, but it's hard to know if that's thermister temperature or top of glass temperature.

I have just started using the heat with the pla. I use it at about 55c. When I was doing ABS a few weeks back, I used 110 C on it. The top of the glass was just a few degrees different. I am using 1/4" pyrex type glass. It transfers the heat pretty well, but ambient temp in the house does cool the top a bit.

Leeway wrote:I have just started using the heat with the pla. I use it at about 55c. When I was doing ABS a few weeks back, I used 110 C on it. The top of the glass was just a few degrees different. I am using 1/4" pyrex type glass. It transfers the heat pretty well, but ambient temp in the house does cool the top a bit.

Does anyone know if the pyrex glass can be cut? I want to cut a small slot on one end for the wires maybe with a dremel diamond wheel.
Thanks if anyone knows for sure.

Eaglezsoar wrote:Does anyone know if the pyrex glass can be cut? I want to cut a small slot on one end for the wires maybe with a dremel diamond wheel.
Thanks if anyone knows for sure.

Unfortunately you can't. The glass is not meant to be cut or drilled by us (unless you have a precision water cooled diamond saw), it just breaks or cracks.

Right. It doesn't act like tempered glass that will just shatter instead of cracking. Mine had a chip in the corner when it arrived, but is still okay. If that were tempered, it would have shattered. Maybe a nice tile saw could cut it, but any mistake could be costly.

michaellatif wrote:

Eaglezsoar wrote:Does anyone know if the pyrex glass can be cut? I want to cut a small slot on one end for the wires maybe with a dremel diamond wheel.
Thanks if anyone knows for sure.

Unfortunately you can't. The glass is not meant to be cut or drilled by us (unless you have a precision water cooled diamond saw), it just breaks or cracks.

McMaster Carr is sort of expensive for this glass, do you know of a less expensive source?

That's the only place I could find, but I only did a limited/simple search.
I did find a source a bit cheaper that is local to me that will cut custom sizes, unfortunately its a 2.5 hour drive. . . one way :-/.

Anyone else have a good source? I have a need to get a 8"x8" piece for another printer.

Well my heated bed with 75 watts at 12 volts is working good. It does take a little time for it to get to temp but I am retired and not going any where so I can live with it. It is nice to have parts with flat bottoms. I have some big parts that need printing so will see how it does on those.

Leeway wrote:Sounds like you could do with a larger power supply, amp wise.
Mine is a 30 amp supply and it gets the bed to 110 C in a couple minutes.

Unless his supply is crowbarring or cutting out, he needs more volts, not amps. Whether he's got an 12v 8A supply or 12v 30A supply, if the heater only draws 6A, it's going to heat up at the same rate with either.

skrubol wrote:

Leeway wrote:Sounds like you could do with a larger power supply, amp wise.
Mine is a 30 amp supply and it gets the bed to 110 C in a couple minutes.

Unless his supply is crowbarring or cutting out, he needs more volts, not amps. Whether he's got an 12v 8A supply or 12v 30A supply, if the heater only draws 6A, it's going to heat up at the same rate with either.

That isn't my experience with a heat bed. Initially I used a 24 VDC supply that is rated at 3A. It was slow to heat.
The 12 VDC 30 A heats fast. I'm not an electrician or electrical or electronics engineer. Just relating my experience with the Prusa heat bed.

Leeway wrote:

skrubol wrote:

Leeway wrote:Sounds like you could do with a larger power supply, amp wise.
Mine is a 30 amp supply and it gets the bed to 110 C in a couple minutes.

Unless his supply is crowbarring or cutting out, he needs more volts, not amps. Whether he's got an 12v 8A supply or 12v 30A supply, if the heater only draws 6A, it's going to heat up at the same rate with either.

That isn't my experience with a heat bed. Initially I used a 24 VDC supply that is rated at 3A. It was slow to heat.
The 12 VDC 30 A heats fast. I'm not an electrician or electrical or electronics engineer. Just relating my experience with the Prusa heat bed.

Your 24v supply was probably tripping. Was probably only actually on a small amount of the time. If the bed was made for 12v, 75W, at 24v it would pull around 12A. No way a little 3A power supply is going to hold up to that.

I don't understand all the things about it. I know the 24 VDC is a Condor linear supply and the 12 VDC can be adjusted some and is a switching type. Typical cnc machine supply made in China. Not that the later has any bearing on how it works. Both work well.
I didn't have a meter on it when it was connected, so it very well could have been dropping out intermittently.

Leeway, just realized what the shark guard was all about! I actually looked into your guards a few years ago, I think I found you from the cnczone forums maybe? Anyways, just thought I'd say that.

Thanks, John.
I am a frequent flyer at the Zone. I could not have built all my cnc machines without the members and resources available there.

With the guards, it seems every time I step up production with a new machine, orders increase by the same factor, so there has always been a lead time on those.
That is a good thing for me, not so good for the customers.
I am working on completing my plasma cutter now. Just had it's shed installed last week. That should decrease leads quite a bit.
Nice machines you guys are putting out as well.
I flipped a coin over the Prusa or the H-1 and it was Prusa.
I like the linear bearing version that I have.
Great Forum you guys have started here as well.
It has to be the most used 3D printer Forum I have seen yet and can only get better.
Good luck with it and your business. I'll help when I can.

Thanks!

This just in! SeemeCNC H-1.1 is almost ready for release. Lunear bush/bearings, lowered hdwr count, faster assembly and more!

michaellatif wrote:

Eaglezsoar wrote:Does anyone know if the pyrex glass can be cut? I want to cut a small slot on one end for the wires maybe with a dremel diamond wheel.
Thanks if anyone knows for sure.

Unfortunately you can't. The glass is not meant to be cut or drilled by us (unless you have a precision water cooled diamond saw), it just breaks or cracks.

You mean like a tile cutter? I might wanna look into a heatedbed and i got a tile cutter, water cooled, diamond saw blade

Seems to be the one thing my waterjet wont cut, ask me how I know

JTCUSTOMS wrote:Seems to be the one thing my waterjet wont cut, ask me how I know

Ouch. I can only imagine the aftermath.

tom10122 wrote:You mean like a tile cutter? I might wanna look into a heatedbed and i got a tile cutter, water cooled, diamond saw blade

That will be to rough of a cut breaking the glass. As far as I know there are no consumer grade tools available to be able to cut this glass.
If you do find one or something that will work, let us know! I would love to be able to make custom sized glass plates for my machines.

Thks Lee for the material I am finishing the build out tonight but just cam to the realization I don't have a wiring diagram on the connection from the hotbed Phebe to the vellamen unit can anyone provide the diagram or how to my brain is having a moment today.

wildideas1, JOhn here. The Phebe has two seperate traces for the 12V connection. Just run the 12V from the velleman to one of the +12V and jumper over to the other +12V on the board. Same for the ground wires. Other than that, thermistor goes on the pad, and wires in same way as the hot end setups.

well darn. I melted my h1.1 bed and never got past 95c. Has anyone used aluminum or mdf for a bed? And is the glass above the heated bed or below
--- I know it was a noob move but heck I was just in the thick of the learning curve.. wonder what else I'll melt besides abs