Better Build Parts and Manual Needed

[stillcopper]

I'm experienced at working on small-parts equipment, with over 30 years in the equipment trade, so these comments are well founded. While the Rostock MAX is well engineered 'on the board' , the materials are still in need of more research. The Rostock V2 would be better described as a Beta2 version as there are still some wrinkles with the parts quality.

--First thing, get rid of the self locking nuts. They are the most problematic of all the current parts. Not suitable for the soft material Rostock is made of. We had 4 of the nuts lock to the point of rotating in the capture slots due to the pressedboard frame. Some spots we could hold nut with needle nose, no way to hold the nut manually while tightening in several spots as the slots are too far in from edge of material. A set of parallel jaw pliers would work, but that's another $30. Never use capture material (pressboard in this case) softer than the nuts captured if self-locking. One twisted off the bolt head well before bottoming out. Another locked to the bolt while running it down onto the bolt prior to installing. And I only use manual screwdrivers for small builds such as this. Power drivers have too much torque and you don't get the feel if there's a bind. Threw away rest of the lock nuts and replaced with standard, using locktite.

--#4 bolts for hotbed too short. Upgrade to 1 in. length. With spike nuts down flat to material, none of the current 1/2" bolts will give full thread engagement, under-engineered. Replaced with 1in, couldn't get 3/4 locally, but they would have worked.

--While the laser cuts are very precise in placements of holes for alignment, they appear to be out of tolerance for the capture slots for the nuts. And SEEMECNC knows this. The reference in the manual to holding the nuts in with tape if the holes are too large backs this up. I found more holes too tight, requiring polishing the holes not carving them, just to get the original locking nuts to slip in. Interesting, standard nuts we purchased, after disposing of the locking nuts, fit in the holes properly. Poor quality locking nuts? Would explain the locking problem.

--Couple of photos don't match the description. Prime example, the upper limit switches for the arms are shown on wrong side of mount.Text gives correct description. Videos were enough to give you a headache. Put the camera on a tripod or at least use a higher grade cam with motion compensation. Yes, I'm getting picky, but for $1000 I would expect better documentation.

--Black bearing housings are not a slip fit, they are heavy press. I've dealt with such enclosures for many years and the only good way to seat the bearing without cracking the plastic is to heat the plastic housings in 180F water for a minute till too hot to handle. They'll expand just enough you can hand press the bearings in. Otherwise you stand a chance on cracking them. And NEVER beat on the bearing or housing. These should really come pre-assembled.

--Might be more personal than other things, but major companies I've dealt with put all the nuts, bolts, and hardware in general in a single bag. Various sizes are in their individual bags, within that bag. SEEMECNC makes it verrrrry difficult to do a pre-inventory with the current method of spreading similar parts over many bags. If a project uses 22 of #6-32 bolts I expect to find a single packet of 22 bolts and be able to count them without opening other packs to get there. The current way is to cut open each 'special' bag to see if everything is there making it very easy to loose or misplace something.

--I'd be interested in knowing the cost difference in using a stable PVC for the frame instead of the pressboard. It could still be laser cut and I've got to believe it would be less prone to environmental change. Moisture changes the current material since the edges are still exposed.

Time involved is much as stated, taking out the poor quality nut problem. Finished the main unit build, headed to the electronics and wiring hookups. Will update when we get through that part.

[Eaglezsoar]

It is interesting how thousands of users built these printers and did not appear to have all the problems you are having.
The comment "Videos were enough to give you a headache. Put the camera on a tripod or at least use a higher grade cam with motion compensation. Yes, I'm getting picky, but for $1000 I would expect better documentation.
was enough to want me to put my fist to my computer.
The documentation for this printer kit is the best you can find for any printer kit bar none.
I am going to quit typing before I write something that I will regret but you seem like a user that would be better suited to a pre-built printer.
You also remind me of someone who bitches about a $500 bonus not being $600.
If I sound angry, it is because I am, do not bother to reply to this because I am not interested in reading any more garbage that you spew.

[Nylocke]

I think you stuck a nerve with Eagle. The written documentation is done by someone who is essentially a volunteer. I think the main form of payment that Gene gets is maybe a free kit every once and a while (major updates) to do the documentation for. Considering this its really quite good I would say.

I can honestly say after building 3 different kits (including a V1) that I have had the locknut problem you described exactly once, so while I understand I don't think its as big of an issue as you say. There are better things to use but it doesn't seem to be a bad system from my experience/the experience of others.

The secret I've found for getting the bearing covers on is to use soft jaw clamps (the ones where you pull a lever to tighten them). They are supposed to be tight on the bearings so they don't pop off during use. I think the whole heated water thing is a little overdoing it but if it works then it works.

It has been a while since I've built a kit packaged by SMC, but I don't recall having any issues identifying fasteners. The 1" #6 screws were distinguishable from the 1.75" and 2", and the 2 different #4 screws were countersunk vs caps head. The M3 and #4 are a little similar, but the M3 screws should have been pan head philips?

The frame material has been brought up. Some people paint the edges to seal them a bit better. There was a V1 made of laser cut aluminum. Personally if you're that worked up about it I would recommend the MAX Metal from tricklaser, its fewer pieces and the frame is completely aluminum. Its really a pretty solid machine once done (build logs in this subforum and in the other machines subforum), but it does require some additional hardware (3D printed or machined, etc) to be complete.

This forum and kit shouldn't be without some criticisms, but please try to be understanding about the amount of time and effort Gene has put into the written docs. I'm sure if you bring this up in the appropriate thread in the V2 subforum he will fix the images to make it more clear.

[Xenocrates]

So, I'll go ahead and address a few things. Firstly, the self-locking nuts are almost essential on a printer. Seriously. The steppers run at frequencies sufficient to dislodge nuts rather rapidly. I had the endstop nuts, which are about as far from the steppers as is possible come lose fairly quickly, until threadlocked into submission (Which, when dealing with frame elements you may need to disassemble is bad).

Second item is one I'll give you though. It's been brought up before. I think there's some length variation in the screws, and that they are designed to just barely engage (I don't like it, but had no issues assembling my bed)

Three: The manual is not written by SeemeCNC. It is written by Geneb (who is on these forums, has a feedback thread on his manual, and will likely be along shortly) There may be some variation in the nuts. There is also variation in the laser, and it's kerf. Depending on the age of the tube, the temperature that day, the humidity when a panel was made, and half a dozen other factors, it is very possible to have kerf changes measurable in the tenths of thousandths. That doesn't even account for variation in the nuts, which, considering that they are not exactly going to be individually inspected or machined, will be off spec slightly (But not out of tolerance). When the two mis-match sufficiently, they are either loose, or don't fit. I just put loose nuts in tight slots.

Four: The manual EXPLICITLY says to follow the text, not the pictures, as some of them are from earlier revisions, or had issues, and Geneb isn't going to tear apart a functional machine to re-shoot two or three pictures for someone who isn't bothering to read what he's writing (And the checkpoint videos should catch mistakes caused by following pictures) They also may illustrate multiple sub-assemblies, but are only for reference of a single one.

Five: I have not dealt with the bearing housings, and so will not comment beyond that being Acetal, they are very unlikely to crack (I say this as a CNC machinist who has done all sorts of stupid things with it. It may warp in some way, but they will not crack, and as they are used only as idlers, and the extrusions do the actual linear guiding, that matters fairly little)

Six: It really depends on what your goal is for assembly. If you want a pre-count on all components before starting the build, your way is better. But as SeemeCNC is selling a consumer machine, and most consumers don't think like that, they do it like Lego does, and put the components for a step in a bag. It makes sense, especially since I noticed that in general, I had some small quantity of left-over fasteners, rather than too few. It also makes it easier for them to package sub-assemblies, and if there are issues, or someone say, wants the top deck off a V2 to upgrade their V1, they can just pick up the appropriate pack and ship that.

Seven: The cost difference, considering that PVC will not laser cut without destroying the laser in a matter of days, being chlorine based, is immense. It is also not stable at the sorts of temperatures that the printer will experience (The snowflake for example, is routinely heated to 100-120C, and the area immediately under it would also experience very elevated temperatures). PVC will bend when left in a hot car, far below the temperatures involved there. The next most appropriate material would be sheet-steel, as marine grade baltic birch is not consistently flat enough for these uses (I laser cut several large sheets of it a year), PVC is not laser-cuttable, nor is poly carbonate, acrylic will crack, warp, and craze. That would greatly increase the price. As it stands, the Rostock Max V2 is considered the most cost effective large printer. Others with similar print areas are usually far more expensive (The closest challenger appears to be the E3D Big-box, which cuts some corners better left un-cut in my opinion (The use of a RUMBA board rather than a Rambo, which means you lose the trim-pot and will need more cooling for the stepper drivers, and shares a dis-advantage of most cartesians, being a slow Z-axis meaning you can't use as much Z-hop, as well as having the Y axis geared, which slows that as well) . If one paints the edges, as is suggested, then you have no issues. Not to mention that the residue from the binder fairly effectively seals the edges of laser cut parts, and that they appear to be using a high-quality panel using exterior grade binder, meaning it is rather moisture resistant. I keep mine in a barn with no air-con, and which also has a water cooling system for a laser cutter, which includes an unsealed bucket of water flushed from the system. So far, no humidity problems.

Now, over all, as many have stated when they introduced themselves, the quality of the manual is the best of any that they have been able to find. Make Magazine named it best value in a comparison of printers late last year. A professional unit capable of the things this is runs into five, if not six, digits. The proof of the quality of the printer, is of course, in what you make with it. I hope that you get yours well assembled, and that the forum as a whole gets over what might be perceived as getting off on the wrong foot.

[barry99705]

So, I'll go ahead and address a few things. Firstly, the self-locking nuts are almost essential on a printer. Seriously. The steppers run at frequencies sufficient to dislodge nuts rather rapidly. I had the endstop nuts, which are about as far from the steppers as is possible come lose fairly quickly, until threadlocked into submission (Which, when dealing with frame elements you may need to disassemble is bad).

Second item is one I'll give you though. It's been brought up before. I think there's some length variation in the screws, and that they are designed to just barely engage (I don't like it, but had no issues assembling my bed)

Three: The manual is not written by SeemeCNC. It is written by Geneb (who is on these forums, has a feedback thread on his manual, and will likely be along shortly) There may be some variation in the nuts. There is also variation in the laser, and it's kerf. Depending on the age of the tube, the temperature that day, the humidity when a panel was made, and half a dozen other factors, it is very possible to have kerf changes measurable in the tenths of thousandths. That doesn't even account for variation in the nuts, which, considering that they are not exactly going to be individually inspected or machined, will be off spec slightly (But not out of tolerance). When the two mis-match sufficiently, they are either loose, or don't fit. I just put loose nuts in tight slots.

Four: The manual EXPLICITLY says to follow the text, not the pictures, as some of them are from earlier revisions, or had issues, and Geneb isn't going to tear apart a functional machine to re-shoot two or three pictures for someone who isn't bothering to read what he's writing (And the checkpoint videos should catch mistakes caused by following pictures) They also may illustrate multiple sub-assemblies, but are only for reference of a single one.

Five: I have not dealt with the bearing housings, and so will not comment beyond that being Acetal, they are very unlikely to crack (I say this as a CNC machinist who has done all sorts of stupid things with it. It may warp in some way, but they will not crack, and as they are used only as idlers, and the extrusions do the actual linear guiding, that matters fairly little)

Six: It really depends on what your goal is for assembly. If you want a pre-count on all components before starting the build, your way is better. But as SeemeCNC is selling a consumer machine, and most consumers don't think like that, they do it like Lego does, and put the components for a step in a bag. It makes sense, especially since I noticed that in general, I had some small quantity of left-over fasteners, rather than too few. It also makes it easier for them to package sub-assemblies, and if there are issues, or someone say, wants the top deck off a V2 to upgrade their V1, they can just pick up the appropriate pack and ship that.

Seven: The cost difference, considering that PVC will not laser cut without destroying the laser in a matter of days, being chlorine based, is immense. It is also not stable at the sorts of temperatures that the printer will experience (The snowflake for example, is routinely heated to 100-120C, and the area immediately under it would also experience very elevated temperatures). PVC will bend when left in a hot car, far below the temperatures involved there. The next most appropriate material would be sheet-steel, as marine grade baltic birch is not consistently flat enough for these uses (I laser cut several large sheets of it a year), PVC is not laser-cuttable, nor is poly carbonate, acrylic will crack, warp, and craze. That would greatly increase the price. As it stands, the Rostock Max V2 is considered the most cost effective large printer. Others with similar print areas are usually far more expensive (The closest challenger appears to be the E3D Big-box, which cuts some corners better left un-cut in my opinion (The use of a RUMBA board rather than a Rambo, which means you lose the trim-pot and will need more cooling for the stepper drivers, and shares a dis-advantage of most cartesians, being a slow Z-axis meaning you can't use as much Z-hop, as well as having the Y axis geared, which slows that as well) . If one paints the edges, as is suggested, then you have no issues. Not to mention that the residue from the binder fairly effectively seals the edges of laser cut parts, and that they appear to be using a high-quality panel using exterior grade binder, meaning it is rather moisture resistant. I keep mine in a barn with no air-con, and which also has a water cooling system for a laser cutter, which includes an unsealed bucket of water flushed from the system. So far, no humidity problems.

Now, over all, as many have stated when they introduced themselves, the quality of the manual is the best of any that they have been able to find. Make Magazine named it best value in a comparison of printers late last year. A professional unit capable of the things this is runs into five, if not six, digits. The proof of the quality of the printer, is of course, in what you make with it. I hope that you get yours well assembled, and that the forum as a whole gets over what might be perceived as getting off on the wrong foot.

+1000

I had a couple of the lock nuts seize up and break the bolts too. It happens. It's not like we're using grade-8 hardware here. It's mass produced in quantities of millions a day, some of it will be crap, that's how it goes.

[geneb]

--First thing, get rid of the self locking nuts. They are the most problematic of all the current parts. Not suitable for the soft material Rostock is made of. We had 4 of the nuts lock to the point of rotating in the capture slots due to the pressedboard frame. Some spots we could hold nut with needle nose, no way to hold the nut manually while tightening in several spots as the slots are too far in from edge of material. A set of parallel jaw pliers would work, but that's another $30. Never use capture material (pressboard in this case) softer than the nuts captured if self-locking. One twisted off the bolt head well before bottoming out. Another locked to the bolt while running it down onto the bolt prior to installing. And I only use manual screwdrivers for small builds such as this. Power drivers have too much torque and you don't get the feel if there's a bind. Threw away rest of the lock nuts and replaced with standard, using locktite.

The nut-pocket/nylon locknut assembly method has been in use for quite some time for a LOT of different things. It's a tried and true assembly method for these kinds of materials. It's commonly known as a "captive nut joint" or [groans] a "Pettis Joint". (http://makezine.com/2012/04/13/cnc-pane ... -notebook/)
If you're spinning the nut in the pocket, you've either cross-threaded the screw (likely) or you've got a defective nut (possible).

--#4 bolts for hotbed too short. Upgrade to 1 in. length. With spike nuts down flat to material, none of the current 1/2" bolts will give full thread engagement, under-engineered. Replaced with 1in, couldn't get 3/4 locally, but they would have worked.

I'll agree that the screws are too close in length tolerance, however they're perfectly adequate for the job. I should point out that the supplied screws are 3/4".

--Couple of photos don't match the description. Prime example, the upper limit switches for the arms are shown on wrong side of mount.Text gives correct description. Videos were enough to give you a headache. Put the camera on a tripod or at least use a higher grade cam with motion compensation. Yes, I'm getting picky, but for $1000 I would expect better documentation.

If you've got an actual example, I'd be happy to check it out. All the photos in Section 8.3 are correct. [They match all the machines in my office, so if you corrected my "mistake", you've basically guaranteed that the end stop screws on the carriages will never engage the switches.]
Yes, I've flipped photos in the past, but as far as I'm aware there are NO flipped photos in the 4th Edition.

--Might be more personal than other things, but major companies I've dealt with put all the nuts, bolts, and hardware in general in a single bag. Various sizes are in their individual bags, within that bag. SEEMECNC makes it verrrrry difficult to do a pre-inventory with the current method of spreading similar parts over many bags. If a project uses 22 of #6-32 bolts I expect to find a single packet of 22 bolts and be able to count them without opening other packs to get there. The current way is to cut open each 'special' bag to see if everything is there making it very easy to loose or misplace something.

The world's best kit manufacturer packaged their hardware the same way that SeeMeCNC does. Maybe you've heard of them. They were known as Heathkit. [Don't confuse them with the current pile of rabid monkeys that are running "Heathkit" currently.]

--I'd be interested in knowing the cost difference in using a stable PVC for the frame instead of the pressboard. It could still be laser cut and I've got to believe it would be less prone to environmental change. Moisture changes the current material since the edges are still exposed.

Ok, now I'm pretty sure you're just making stuff up. Everyone that's had even a passing experience with a laser (beyond, "Hey! I saw one once!") knows that cutting PVC with a laser is an amazingly efficient way of killing the laser and filling their shop with toxic fumes. See when PVC is laser cut, it emits a high temperature chlorine gas. When this gas condenses on to the stainless steel hardware used in lasers, IT DISSOLVES IT. The stuff is so nasty that the warranty form for my Epilog laser is so strict that I can void the warranty by simply PLACING a sheet of PVC into the laser without cutting it.

Time involved is much as stated, taking out the poor quality nut problem. Finished the main unit build, headed to the electronics and wiring hookups. Will update when we get through that part.

I look forward to seeing how the rest of the build goes for you. Just don't forget to move those end stop switches or you'll not be able to calibrate the printer.

g.

[mhackney]

PVC is also not a good structural choice - it is no where near as rigid as the melamine panels currently used. That would requirer thicker PVC and the whole thing spirals downward from there.

As for mass bagging versus modular bagging... I manufacture and sell fly fishing reel kits. 1000s of them all over the world to many different countries and languages. Over the years my packaging has also migrated to precisely the same modular packaging for exactly the same reasons - it is much easier for the consumer to locate the correct parts at the time they need them. My BOM included with the kit is also modular so there is no need to open every bag up front and each module can be checked as you go. If you wanted to check everything up front, I do use clear poly bags so you could count parts without opening the bags. The praise I've had on the ease of assembly since I moved to this method of packaging increased tenfold.

Lock nuts are lock nuts. They are a pain in the rear no matter what. One trick is to pre-thread with a screw. It does lower their holding strength but it's a reasonable compromise. Otherwise, it's messing with LocTite everywhere and that's a different pain in the rear.

[geneb]

it's messing with lactate everywhere and that's a different pain in the rear.

That is pure autocorrect gold.

g.

[mhackney]

Ha ha! I edited my post to correct to LocTite.

[DeltaCon]

Stillcopper seems to be pretty still...
Guess I would create a new account with a different name if I needed any more advise from this forum

[mhackney]

It's fine. Constructive criticism is a good thing and he put some thought into what and how he wrote it.

[geneb]

Yeah, I have no objection to what he wrote, regardless of how wrong it was.

(I'm kidding, relax! Besides, Eagle threw my glasses for me. )

g.