First printer build....Delta, Mendel, or something else

So I am starting to plan my first printer build, but keep going back and forth between two designs...the Delta (probably 3DR) and the Mendel (probably Mendelmax 1.5+).

Right now the plan is to source all the parts and do any cutting/drilling of extrusions, rod, etc myself. I am a mechanical engineer with extensive experience in ground up design, metal fabrication, electrical wiring/soldering, computer building, computer case modding, etc etc. The software side is by far my weakest point, but I'm not completely foreign to that either.

My main question is which is the better printer outright and which can be sourced for less money (just in a general sense before I start sourcing all the components)? I am more interesting in accuracy and consistency than I am speed (though I don't want it to be slow as a dog).

Also, if there is something else that would be in comparable price range for the components that would be better (or as good but cheaper) that would be good info as well.

Thanks.

My first was a Huxley from RepRapPro as a kit.

I've now learnt how it all works, and now I'm just deciding which to print as my second printer !

I can recommend kit first, self source second, I was worried about building something that just didn't work, and not having the experience to know why. I skipped that step, now when I print my 3DR, it'll be easy

cheers,

Dave

It depends if you want to print or build.
You should get a kit, you can build it up quickly and along the way
learn the ins / outs of 3D printing machine and realize improvements / fixes.

Then get to the real frustration 3D printing
Extruder hassles, 100s of parameters to set,
Kilometers of filament thru the extruder and one or two good prints

Do you want to spend your time developing a printer
or
printing in 3D?

How about an Ordbot Hadron

[buildlog.net]

I have nothing against a kit (what I was originally planning on), but thought I could save a few bucks by sourcing my own components and cutting my own material (would need to buy printed parts though). If the savings prove to be minimal (say <$75), I'd be inclined to pick up a kit instead.

I really like the look of that ORD Bot Hadron.

go with a Delta, though I'm skeptical of the 3DR and other deltas that use printed parts. Rigidity is crucial for Deltas, and even a few thousands of variance can drive you batty trying to calibrate.

You'd be hardpressed to find a better value than the RostockMax - SeeMeCNC

Huge build envelope, precise, fast, upgradeable...

And if you want to do it yourself, you can buy the laser cut frame and source the rest yourself.

What's the deal with the laser cut wood parts on the RostockMax and Prusas? Wouldn't the swelling of the wood due to humidity and temperature throw off the tolerances?

The all aluminum construction of the ORD Bot Hadron really peaks my interest.

I second cope413's assessment of the Rostock in terms of volume for the money and visual appeal. Richrap's machine does look amazing too though with better self replicability - more printed parts, fishing line instead of belts and so on. The prints look great too.

It's my first build (nearly finished), sometimes very frustrating, but invaluably educational.

The Rostock does look nice, but I just can't stop looking at the Ord Bot Hadron. It seems like it is exactly what I want and is a combination of kit and self sourced in order to build one.

Any reason to not pursue the Ord Bot?

The Ord Bot looks good. Looks like a more expensive version of the i3 frame.

It's not wood, it's melamine coated MDF. (and yes, I am aware that MDF has wood fibers, but it's not the same thing - not even close) I've got over 500 hours on my Max and haven't had any issues whatsoever with shifts/changes/settling of the frame pieces.

Aluminum can certainly offer more rigidity and tighter tolerances, but it's more expensive and there are no readily available aluminum delta kits. And unless you've got an amazing machine shop, the BerryBot isn't a good choice.

If you want to go cartesian, the OrdBot looks nice. But once you go Delta, you never go back

cope413 Wrote:
-------------------------------------------------------
> If you want to go cartesian, the OrdBot looks
> nice. But once you go Delta, you never go back

Why is that though? Is there a real difference in printing performance, precision, accuracy, etc?

Yes, a pretty substantial one IME.

I owned an Airwolf v5.5 previous to my Max, and I've used a Replicator 2 for about 2.5 months.

The layer alignment and speed of the delta is far superior to either. Not to mention I can print huge things that aren't possible on 99% of all cartesian bots.

Lots of people will tell you they print at 150mm/s or whatever, but the vast majority of them don't understand that their firmware comes with preset limits that prevent that.

It's virtually impossible with the current cartesian setups to move that much mass that quickly without overshoot. The real max of most cartesian machines is somewhere in the neighborhood of 60-80. If you ditched the direct drive and got a bowden, and got a really rigid frame like the one you're looking at, then 100+ isn't out of the question - but speed is a huge advantage in the Delta camp.

I can tell you that I can and do print at 100-150mm/s on my delta with excellent results. There's probably some room to increase it too.

The vase in the picture I attached is 250mm tall, and was printed in ABS at a real 90mm/s (jerk max at 60mm/s, accel set to 3000). I likely could have bumped it up a bit, but my Airwolf could only dream of making a print like this...

That's interesting to here and honestly not what I expected after reading some other reviews. Like I said, raw speed is not what I'm after...precision and accuracy is more important to me. I just have trouble getting over the variable resolution of a delta machine and how flexible the frame designs look.

If costs were the same, I think I would go Ord Bot for sure, but it looks like I can build a Rostock cheaper and that is enticing.

It's not difficult to make a very rigid delta. The Max already uses 80/20 towers. If you were to cut some aluminum plates for the base and top, you could make it incredibly rigid.

Consider using carbon fiber delta arms (very inexpensive), and you have a very rigid, very accurate printer. 25micron layer alignment precision is not an exaggeration.

So talk to me about bed level calibration. I keep reading that it is a complete PITA to get the Z-axis calibrated on Delta machines for bed leveling.

It's tougher than cartesian, and it will be harder because this is your first machine so you're not familiar with the process at all, but once you understand how the machine works (and you will become very familiar during your build), it's really not that difficult.

You can save the calibration gcode commands in rephost. It's 4 points - x tower, y tower, z tower, and center point. All that is required is to adjust endstop heights - just like on a cartesian - at each of the 3 tower points. Once those are done, you check the center point to make sure it is at the same height as the towers.

If it is, it's done. If it isn't, you change the delta radius number in the firmware. After the first time, you shouldn't need to change delta radius unless you change something on your machine (delta arms, belts, carriages, etc) that would affect the geometry - so it's just periodically checking your z-height. At most it takes me 5 minutes every 30-40 hours of print time. There will be auto-leveling soon - it's in development stages still, but it's not far off.

So last question because you almost have me convinced to go with a Rostock Max kit over building a Hadron myself (which would be way cheaper). Is there an explanation for the concerns in this review of the Rostock Max?

[www.kronosrobotics.com]

Hi,

Have a read of the SeeMeCNC forums.

I really don't know why some of the members are so divisive (is that a word?) about 3D printing.
Be better if we all learn from eachother.

Here's a quote from a signature..

"Delta Power! Defeat the Cartesian Agenda!"

There's quite a few like that.

Anyway.. have a good read of their forum, before you confirm the "almost" you say above.
(in light of the blog you posted)

Also RichRap has a very interesting blog on "cartesian printers"

here's what you originally wrote
"I am more interested in accuracy and consistency than I am speed"
You don't mention size though. Is size of print an issue ?

just trying to help with your decision, my plan is to print a 3DR when I have time ! Now I understand 3D printing after learning on a Huxley.
Huxley is currently printing everything for me, (but only up to a size of 140x140x80mm!)

Edited 1 time(s). Last edit at 10/16/2013 04:41AM by DaveS.

Size is only a concern when looking at the smaller machines. The build volume of the Ord Bot Hadron is big enough (200x200x180), but the larger volume of the Rostock is just an added bonus.

From reading richrap's blog it looks like he really likes the rostock. I'm going to do some more reading on the seemecnc forums later today.

That reviewer needs to find another hobby. He never asked anyone on the forums or at SeeMe for help. Had he done so, all the issues he encountered would have been easily addressed. The fact that he mounted a direct drive to the effector is just ridiculous.

Also, the machine has changed considerably since that review - new extruder, new delta arms, and new nozzle - so it's not really even relevant anymore.

I'm not one that thinks Cartesians suck. I agree with Dave S on that...

I'm simply convinced that right now that Deltas offer a lot more than cartesian bots in the important specs - speed, precision, and build volume.

After spending some time over at the seemecnc forums, I think I'm going to officially decide the RostockMax is the printer for me. However I think I'm going to buy a laser cut melamine kit from Trick Laser, and source the rest of the components individually from seemecnc and other vendors. I also want to run an E3D hotend because I'm most intersted in printing nylon in the future for more usable parts (after learning on ABS that is).

Learn with PLA - much easier and more forgiving. Skip ABS altogether. When you're comfortable with the machine, just go straight to nylon. Nylon is superior in every way to ABS - stronger, more flexible when thin, better bridging, better interlayer adhesion, doesn't require heated bed, less warp, etc...

And the E3D is definitely the way to go.

I have read that the older E3D's had trouble with running PLA. Is it advisable to run the seemecnc hotend first to bypass these issues or are these issues even relevant with the E3Dv5?

It's great with PLA. The problems are outliers at best. More likely, they're related to some other variable - not the hot end.

Thanks for all the help. I'll be sure to post a build thread over at seemecnc and put the link up in this thread. I'm sure I'll have another couple of questions as I finalize my parts list.