I wanna make new printer and I try to choose between delta system and xy core.Any sugestion what is better ?

You would need to define what you mean by better.
If you list your order of priorities for speed, how easy is it to build, cost, availability of spare parts, reliabilty and any others factors then it would be easier for people to help.
If you plan to build it then it would also be useful to know what significant areas you have skills in. Is English your first language? If not then choices might be limited by build guides available in your first language.
Home made 3D printers are somewhat of an art requiring a fair bit of skill. If it is your first build then I might suggest going for a simpler build.

Looking for good speed and acurency printer.I already have one and wanna make new one from scrach.just not shure what system to choose from delta and xy core.I looking for accurency more like speed but do not want to have slow printer.

A standard cartesian system printer could be called slow I guess, but that's in comparison to a delta bot.

Really what it comes down to is would you like more speed or more accuracy?

What will affect print times a lot is what nozzle size you pick. Keep that in mind.
I have a cartesian based printer that I run at 50mm/sec and I'm happy with that. It may not be blazingly fast, but the quality is very good. I have a 0.5mm nozzle so it puts down plastic much quicker (almost 2 times faster) than other printers with a 0.3 or 0.4mm nozzle.

Have a read on here to see for yourself what I mean: [www.tridimake.com]

I also feel the corexy and delta bots calling me.. must build another printer

Something else to consider re Delta verses xy core is the bed size you want. Tall or Wide? Delta great for height whereas xy core (core xy?) great for width. My "rough as guts" repstrap corexy print volume is 700 x 250 x 200 and comfortably prints at 80mm/s. It could go much wider and faster with a few minor tweaks however it does what I need - for now

Have any pictures AgentX?

Agent,

Does your coreXY have trouble with circles not being perfect? I built a h-bot printer with a build volume of 300mm cubed and still can't get it to print perfect circles. If I print a 20mm calibration cube all the sides come out perfect within .05mm. I think my problem may be the cheap linear bearings I bought from china. The X and Y are sort of rough when moving by hand. I ordered some IKO bearings off of ebay and should have them today.

Thanks,
Greg

Its probably because of the torque a h-bot exerts on the carriage. It's why the corexy was invented. The theory of operation and advantages are discussed here.

Edited 1 time(s). Last edit at 07/09/2014 03:43PM by TheTechnicalNoob.

Very cool explanation you provided. I should have researched more before building mine. I got the new rails in yesterday so I will see if any difference can be seen.

it shouldn't be too hard to convert your h-bot to a core-xy setup, if the new rails don't help.

Honestly I think the only reason H-bots are still being built at all is that people just don't know enough about CoreXY. And if you implement a modified CoreXY, it's really simple and easy to build without compromising anything.

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Realizer- One who realizes dreams by making them a reality either by possibility or by completion. Also creating or renewing hopes of dreams.
"keep in mind, even the best printer can not print with the best filament if the user is the problem." -Ohmarinus

I finally got my IKO linear bearings installed and it appears to have solved my circle issue. Only downside is they are shorter so I lost some build volume. I printed a 20mm cube with a 15mm hole in the center. The hole size came out 14.76 +/- .03 through out. I know the slicers seem to always under size holes for some reason but I have gotten used to making my models with the holes a few tenths larger.

I've built my own H-BOT design. http://www.soliforum.com/topic/5141/hbot-printer-or-yahp/

I have yet to build a delta, but here is some of my experiences:

H-BOT:
Pros: Easy to build. If you look at my design, you will see a single belt that is tensioned by having oval mounting holes for the steppers. You just need to snug the belt, no worrying about matching separate belt tensions. I have had perfect circles since day one. And its fast. I have gotten up to 800mm/s speeds before having motor skipping. Realistic speed is 300mm/s before starting to lose quality. I built this for speed to begin with. Now, you should know that 300mm/s speed set in your slicer does not mean you are going to go 5 times faster than 60mm/s in same slicer. Arcs and short lengths mean you do not take advantage of your top speed through intricate print jobs. Only blocky big stuff does it make the greatest impact. Oh, if you get your pulleys and belts from places like RobotDigg, an H-BOT is pretty cheap hardware wise.

Cons: The X carriage flexes out of square unless you have a really rigid system. While someone mentioned bad circles (I never got those) I had problems with squareness. If I printed slow (60mm/s) I had no problems, but at speed cubes ended with one side being slanted. Now, I made a more rigid bearing system, but the frame itself was using thin printed corners that had enough give that the entire printer was flexing during really fast infills. Another con is stepper motor selection. If your building for speed, then do your homework ahead of time. People think that buying the bigger stepper will give you more speed. This is false. It has more to do with the rated inductance and resistance of the motor. Research and put the motors attributes through here:Speed calculator I made sure I bought fast enough steppers to begin with.

HBOT vs Delta: I have yet to build a delta. From my research though, the biggest concern is build volume. Deltas are limited to a circular diameter, but have almost limitless height. H-BOTs are not limited in any build volume direction, but the bigger you go, the more you have to worry about stiffness. If you go beyond 8x8x8" volume, your better use metal frame with metal joiners. Hence all those explanations about H-BOT and CoreXY show all metal construction. Also, none of this discussion compares the H-BOT/CoreXY Z axis. A bad Z axis design leaves wobble and banding no matter how good the X-Y is. Deltas combine all axis together, you tune it in for everything at the same time. One thing I will say is that Deltas have had a big problem with their arms. They are not easy to build. All 6 arms need to be perfect length, and calibrating seems to always be a trick. Out of all of my research, that was really the only CON I could find. I would say an H-BOT/CoreXY is better if your looking for performance/printing structural (big square stuff) while deltas are just pure cool and fun to watch/better for printing artistic stuff. As for quality, both are capable of fine quality prints as long as you build them correctly.

H-BOT vs CoreXY: CoreXY solves the torsion problem on the X carriage by having two belts, but those belts better be well tensioned to each other. That is not a big deal though, adjusting tension is not a daily maintenance. But it only solves the carriage torsion problem. In otherwords, if you use linear bearings and rods, then use a CoreXY belt setup. If your frame is not stiff enough, then CoreXY behaves the same as H-BOT with a loose frame. I was never a fan of crossed belts, so if you go CoreXY use the stacked pulley method in the modified CoreXY link.

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"Never argue with stupid people, they will drag you down to their level and then beat you with experience."