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Re: Stepper motors - now starting to collect parts - 10 years ago

Hi Waitaki, That ali-express link is a perfect example of why I've always been 'apprehensive' with ali-express... The description clearly specifies 42BYGHW609 and yet the attached photo clearly has steppers with a 42BYGHW811 sticker on them. I'd guess that there's a 30% chance of receiving the expected 42BYGHW609 motors. Another 20% change of receiving 42BYGHW811 motors, 40% chance of receiving

by TheRevva - New Zealand RepRap User Group

Re: Electronics - L298N Stepper Motor Driver - 11 years ago

Rather an old thread to dig up, but... The L298N uses BJTs on the outputs as opposed to the DMOS based A498x / DRV88xx chips. Therefore, these suckers would get rather 'warm' by comparison if they were driving something like our 1.7A or so steppers in a RepRap... While they are 'rated' to 2A continuous, they'd need a fairly decent heatsink on each one to achieve anything close to that! Sure, th

by TheRevva - New Zealand RepRap User Group

Re: Hotbed for $18.25 - 11 years ago

Yeah, that does look kinda neat (I was about to say it looked cool, but I then realised the irony). I agree with your calculations, but there's one that I think might end up causing some issues in future. The resistors you've specified are 1/2 W resistors, and yet you've clearly (and correctly) stated you're pushing 1.14W from each one at max power! I suspect they might 'let out the magic smoke'

by TheRevva - New Zealand RepRap User Group

Re: Stepper drivers - failure modes - 11 years ago

Just as a 'follow-up' posting... There's already a company that markets stepper motors with 'built-in' controllers... Specifically, LinEngineering link. While some of their offerings aren't too well suited to the Reprap community, they have others which are a very good fit! The D and DE models should be quite simple to integrate while the C and CE models would be more work. IMNSHO, they should

by TheRevva - Controllers

Re: Holes in prints - 11 years ago

I suspect you meant Thing:19227 rather than Thing:19277? (Just in case someone else wanted to look it up)

by TheRevva - New Zealand RepRap User Group

Re: Prusa I3 BOM Help - 11 years ago

Now THERE is an invaluable piece of info!!! (I'll head to Bunnings tomorrow) I hadn't even _considered_ the mounting (and the follow-on levelling) of my heat bed yet! Speaking of heat beds... My Y-carriage plate not only uses 4 * LM8UU bearings (as opposed to the 3 I've seen on most others), but also expects the heat bed to be mounted on each of the 4 corners. From what I have read, I'm prett

by TheRevva - New Zealand RepRap User Group

Re: Prusa I3 BOM Help - 11 years ago

LOL @ Oatridge... Those 3mm Jaycar nuts fit PERFECTLY... They just require the use of the correct 'tool' (which in my case was a small propane burner...) I held each nut in a pair of needle nose pliers and gave it a good 'warm up'. After that, they literally FELL into their respective slots in the PLA parts. My problem was that the M5 nuts for the Z axis were a lot closer to the correct 'fatne

by TheRevva - New Zealand RepRap User Group

Re: Prusa I3 BOM Help - 11 years ago

Thanx for the good luck wishes... I haven't need the luck yet, but I'm pretty confident I'll want all I can get by the time I've purchased the last of the needed parts. (I'm down to only needing the stepper motors, a hotend and some PLA / ABS) One of the problems we 'beginners' face (if I'm allowed to use that term?) is that there are many variants of each machine and this makes it difficult f

by TheRevva - New Zealand RepRap User Group

Re: Prusa I3 BOM Help - 11 years ago

I think it's almost inevitable that you'll end up with a few (comparatively incidental) extra parts when you're done. I'm building a single plate i3 (my first build of many I hope), and I am not at all concerned that I'll have a small box of bits purchased 'in error' by the time I am done. I don't consider them 'redundant purchases', but rather as forward thinking purchases for the NEXT build.

by TheRevva - New Zealand RepRap User Group

Re: Is This An Authentic Arduino? - 11 years ago

Well dayum!!! I actually didn't think I was 'ranting on a forum', but I'm happy to support that you are, just like myself, entitled to your opinion. BTW, I haven't yet read the text of the links you've provided. You can rest assured that I WILL be doing so. I OWE you at least that much! Furthermore, I guess I need to go back and re-read what I posted, for I NEVER intended it to be insulting.

by TheRevva - RAMPS Electronics

Re: Is This An Authentic Arduino? - 11 years ago

I'm a big proponent of all things of an 'Open Source' providence, so please take that into account in reading this... I am STRONGLY against what the arduino team label as direct counterfiets. However, it's MY (personal) opinion, that the entire 'Arduino Project', which was from the outset, born from open source roots, would do well to take into account some 'commercial realities'. I fully accept

by TheRevva - RAMPS Electronics

Re: Mendel 90 - Anyone want dibond parts? - 11 years ago

Looks MAGIC to me!!! (And it's VERY VERY VERY much like the one I saw last weekend at Mikes Meetup... )

by TheRevva - New Zealand RepRap User Group

Re: New to Reprap - 11 years ago

Hi Greg, I'm in Sth Akld (Pukekohe area).I've only recently started building my first machine (a Prusa i3 in my case) You've askied a few question, so here's MY take on a few answers. Interpret them as you wish. Q1: What unit to build? A1: Whichever one you choose to. There are several designs out there for you to choose from. Even once you've selected a basic design model, you can customise

by TheRevva - New Zealand RepRap User Group

Re: Stepper drivers - failure modes - 11 years ago

Thanx for the reply! I 'd have thought that was fairly easy to circumvent by simply throwing some zener diodes across each field winding output to 'safely' conduct away the induced high voltage shocks? The motor winding is not a HUGE inductance (generally a few mH in our case), so the amount of energy stored in the winding is also not huge (given the 0.5LI2 formula), so the zeners wouldn't have t

by TheRevva - Controllers

Stepper drivers - failure modes - 11 years ago

Sorry if this isn't the right place (I'm fairly new). I've heard that there are 'issues' with the stepper drivers letting out their magic smoke if they are disconnected when powered. Does anyone here know the failure mode that this causes? I'm _considering_ designing a slightly different stepper driver (although still based on an A49xx or DRV88xx chip) that mounts directly to the back of the st

by TheRevva - Controllers

Re: Auckland 3D Printing Meetup - 11 years ago

Thanx a bunch for the link!!! There's nothing at all wrong with 'weird imperial'... I grew up with the stuff!!! (Actually, that's a LIE! I refuse to 'grow up') I'm confident it will come in VERY useful on my second (or perhaps third?) machine build. (Which I'm planning to be both an additive AND subtractive machine with selectable 'tool heads'). Since I'm still in the 'crawl' stage of the age

by TheRevva - New Zealand RepRap User Group

Re: Auckland 3D Printing Meetup - 11 years ago

Thanks HEAPS for putting on this meeting Mike... (I was the idiot who turned up late as hell... LOL) It was great to see an assortment of printers (including an I3 that's near identical to the one I am building). You looked pretty busy with all your guests, so I didn't bother 'interrupting' you with an 'official' intro. I'll touch base with you sometime in the near future (via the storefront) to

by TheRevva - New Zealand RepRap User Group

Re: Auckland 3D Printing Meetup - 11 years ago

Damned good point!!! I'll go rustle myself up a list tonight (after I confirm how sad my bank balance looks... LOL) Edit: A 'preliminary list' I just threw together has already exceeded my self-designated 'monthly reprap allowance'... As they say in the Toyota adverts... "Bugger"

by TheRevva - New Zealand RepRap User Group

Re: Auckland 3D Printing Meetup - 11 years ago

Hi Mike, I cannot guarantee I can make it, so I'm only a 'tentative'. However, if I _DO_ manage to make it, you better be prepared to sell me stuff... (Yes, I WILL be bringing along a 'shopping list'... LOL)

by TheRevva - New Zealand RepRap User Group

Re: New Member wanting to Build any help would be awesome! - 11 years ago

Hi Kev, I too am very new to the reprap scene and have just started gathering all the bits for an i3. I'm in Sth Auckland - rural Pukekohe area so if you happen to go the route of an i3 and / or are anywhere in the area, I'll do whatever I can to assist. In my case, I wanted to source as much as possible of the parts myself rather than grabbing a kitset. (Purely for added fun... Or perhaps that

by TheRevva - New Zealand RepRap User Group

Re: 1.75mm PLA Hotend recommendations - 11 years ago

AHA!!! I'll try hotends.com again next week! Thanx for the heads up on order timing.

by TheRevva - New Zealand RepRap User Group

Re: A "just how cheap can you go" thread... - 11 years ago

I think I might _LIKE_ this AliExpress site.... Take this for example... Arduino Mega It'd be hard to beat $US14.24 (NZ$18-ish) for an R3 Mega 2650 clone, and then you realise that's the price for TWO of them and includes free shipping... I think I'll order half a dozen, just for kicks...

by TheRevva - New Zealand RepRap User Group

Re: A "just how cheap can you go" thread... - 11 years ago

This looks like a fairly good price: AliExpress US$59.95 (roughly NZ$74.00)

by TheRevva - New Zealand RepRap User Group

Re: Printable PCB Mill - 11 years ago

I'm considering doing something similar (but only AFTER I've completed work on building the i3). How are you going to keep the PCB itself from 'bowing up' and otherwise moving about on the bed? (All the FR4 I get has some degree of 'bow' in it along one axis). Are you considering using the same tool / bit to perform both the routing of tracks and any through holes, or are you contemplating chang

by TheRevva - CNC Routers, Mills, and Hybrid RepRapping

Re: Raspberry Pi based electronics ideas - 11 years ago

Edit: Please scrap the post below - It's already been done apparently... LOL Looks like this thread is a little stale, but there MIGHT be some interest? Digilent have a PIC32 board that is basically an Arduino Mega form factor. (They call it a MAX32) Link to MAX32 Sure, it's a 3.3V processor, but from what I can see, a standard RAMPS1.4 will work just fine at 3.3V. The A4988 polulu stepper drive

by TheRevva - Controllers

Re: Introducing the ramps 10 - "Ramps10" an open source multi-configurable stepper controller shield based on the Ramps 1.4 design. - 11 years ago

Hi all, I'm comparatively new to RepRap so I'm still in the 'hyper-inquisitve' phase. (I've barely just started my first build) I'm quite possibly a little 'off topic' here so send me flames as appropriate. Given that the proposed 'RAMPS10' looks to be another monolithic stepper controller board, I figured this is as good as place as any to ask. I've read in several places that the limit on ste

by TheRevva - Developers

Re: An 'open question' for the local reprap community... - 11 years ago

Thanx fior the 'heads up' Waitaki... I'll not be bothering anyone here anymore.

by TheRevva - New Zealand RepRap User Group

Re: An 'open question' for the local reprap community... - 11 years ago

Hmmm, no responses? Not sure if that's a GOOD thing or a BAD thing... I guess I'll just keep going until I'm told otherwise... Here's one of the many 'thoughts' that I've been pondering over: From what I understand, it's not uncommon to be throwing out stepper motor steps at 40kHz. Admittedly, these are most often 1/16-step microsteps so the 'effective' signal being transmitted is a stepped si

by TheRevva - New Zealand RepRap User Group

An 'open question' for the local reprap community... - 11 years ago

Hi guyz'n'galz, I was beginning to wonder whether or not I am 'abusing the intent of this forum'. It's (painfully) obvious to anyone that I'm VERY new to the reprap. and perhaps equally obvious that I'm VERY enthusiastic and inquisitive about ALL aspects. It's no surprise to me that almost every time I come across a 'eureka moment', I will find that someone, somewhere, has 'been there, done tha

by TheRevva - New Zealand RepRap User Group

Biting the proverbial bullet. - 11 years ago

I can only 'procrastinate' for so long before it gets old... (A week was already too long considering my impulsive nature!). I just placed the order for the plates and plastics of a Prusa i3 to get the ball rolling. The birth of (another??) Sth-Akld based i3 is inexorably 'looming on the horizon'.

by TheRevva - New Zealand RepRap User Group