Show all posts by user
Plastic Extruders, mostly - > http://objects.reprap.org/wiki/Extruder
Re: Gah. Fried Power Supply - defective? - 12 years ago
Back in the good old days (really old) they actually used to test things. In the late 90s I did desktop (IT) and a typical "good" failure rate for PCs was around 4%. That's when around two large bought you a shiny new 100 MHz Pentium. Laptops fared far worse, with nearly a quarter of them going belly up, at a paltry $4500 each on average. In 1998, one well known PC manufacturer who shall remain nby Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
Thermal considerations aside, the ability to make fine adjustments, and to precisely align my printer are prime considerations. Usually, once you start making things adjustable, you sacrifice simplicity to do so. The machining capacity for a single piece this size I simply don't have, but even if I did I would have to work on the assumption that everything else is perfect, to within about .001 inby Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
The thing you have to realize about a printer of this size, is that more size means more heat. An 18 x 28 inch heat bed. 7 extruders. And all enclosed. The problem with many kinds of plastic parts in this environment is that the heat would cause them to deform over time either suddenly or imperceptibly slowly, depending on their location. Also there is size to be considered... A 15" build heightby Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
Well, all I would really need is a somewhat larger printer... Foam is not a good candidate for use in an enclosed printer. It would melt or likely burn. Also, the electronics would fry. I would certainly say this was no easy part to make by hand, but ultimately is the optimal design for the overall goals of this printer. Besides, I had an Erector set when I was little, and always kind of liked tby Maxx Mayhem - Reprappers
Re: Do you print unattended: overnight or away? - 12 years ago
You must trust your machines. If they don't work, fix the problem and trust them next time. If you don't trust your machines, they will know it and will never do what you want. (I'm figuring if it's true for cars, it likely applies to printers as well) I am building a machine with 50 micron resolution (target) and a 3.5 cubic foot build envelope. I do not think I'll get many chances to watch anyby Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
I have completed the frame for my build stage, and if all goes well, I'll install it tomorrow. This will be the first moving part, so I suppose now the real fun begins...by Maxx Mayhem - Reprappers
Re: Thing-O-Matic Restoration - 12 years ago
Nice to see somebody keeping the old machines on the road!by Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
If it proves to be an issue, I may get the rod with the backing track and the "C" linear bearings, and fit the track to accommodate my adjustment system. VXB carries it .The track I would attach to a piece of machined square tube, or some big chunk of aluminum, either at the side, or overhead. Alternately, I could machine up some supports and adjustable mounting brackets, still requiring the opby Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
Thanks, CNCD. There are 12 integral mounting points to attach the bed, I will likely need to fabricate some sort of XY "T" mounts...I first have to talk to the heater rep to see what I would have to work with as far as holes are concerned. They can route the heater wires around holes, but I don't want to lose consistency. I will likely end up doing a thicker plate as well. BTW, you wouldn't happeby Maxx Mayhem - Reprappers
Re: can I use hook 2 power supplies in parallel? - 12 years ago
Black Dragon, amperage at you household outlet is measured at 120 volts (in the US, varies in other countries) If therefore you have a 12 volt load, you can run 10 such loads of the amperage of your outlet safely, the actual draw in watts will be the same. Simply apply ohm's law. Nothing wrong with multiple PSUs. I'm using 2 and running a 120VAC heat bed.by Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
I am ordering the heated bed beginning of next week. ( I assume my rep is on vacation till then.) I have just finished prepping the final parts for powder coating tomorrow AM. I am nearly a month into this part. Ultimately, I wound up making 59 pieces by hand, and milling nearly 950 holes in total. If all goes well in the morning, I will hopefully have this installed by the end of the day, thougby Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
Actually I have a box of greenfields sitting on my desk, also some unlabeled ones from Grainger that are pretty good. I've learned to avoid at all cost the ones from the home center smaller than 1/4 -20, especially in aluminum. And I use wax, not oil whenever tapping aluminum.by Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
I have been rather busy in the machine shop this week lightening the frame for the build bed. I still have the internal cross - bracing to drill, I'm hoping to finish that along with the edge drilling tomorrow, and I'm waiting for one more size of tap to arrive, so I can finish all the machining and get to powder coat and assembly of this part.by Maxx Mayhem - Reprappers
Re: Remember it could always be worse... - 12 years ago
Uncle Bob, My approach is to 1. apply anti seize 2. snug the bolt down to a reasonable tight* 3.install a safety wire or pin to keep the fasteners from loosening due to thermal or vibration causes. *I have learned a great deal about "apparent" torquing over the years - that is the point at which a really small fastener (# sizes) feels like it is properly tight to do the job, and to be retrievablby Maxx Mayhem - Reprappers
Re: Remember it could always be worse... - 12 years ago
Well Bob, I'm going to have 7 hot ends in a space the size of an egg. I am rather concerned with heat (I will be water cooling) and having a 25 year old Ford, I know rather well the frustration of a fastener or bolt that won't come out. Especially since in that year, they had fasteners that were half and half sae/metric. Aircraft often use the safety wire method of keeping bolts from escaping, Iby Maxx Mayhem - Reprappers
Re: Remember it could always be worse... - 12 years ago
Printer parts are a lot like so many other things in life... The more things heat up - the harder they are to separate. Looking at the issue you had, I'm thinking that it may be a good idea to coat threaded items that are prone to seizing with a small bit of anti seize compound (auto parts store) on the threads of hot ends, hot bed adjustment screws etc.by Maxx Mayhem - Reprappers
Re: Why have the tops of my prints started to slump ? - 12 years ago
Thanks, Nophead. That helps quite a bit.><by Maxx Mayhem - Reprappers
Re: Why have the tops of my prints started to slump ? - 12 years ago
Nophead, how does this generally apply to different colors of ABS (other than white) when supplied by the same vendor? And how would one handle this in the software, in the instance that you are printing with more than one, or more than two colors for that matter when this is a consideration?by Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
Hey Ivan, this is 6061 T-6 - billet, or aircraft aluminum. Though this could be welded, I have opted to bolt it together for accuracy. Minimal strength is required, but absolute accuracy is a must to ensure smooth movement. This piece will never be subject to forces more than say, 50 lbs or so, and each bolt holds a few hundred pounds - there are a lot of bolts. I do have a number of welded alumiby Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
This weekend, I began making up parts for the main frame of the build stage. The vertical frame members, which you can see here are less than a third of the components that go into this piece. Bolt holes and tapping are next. I am still working out a few design details, and hope to finish and mount this item by next weekend. At that time, I can order the custom heat bed, and I'll actually have aby Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
Heck no. Basically, the approach I prefer for this type of a project is to start trying to answer questions, one after the other, with the ideal result being a thing that works. This is an iterative process. I did start out with a basic overall plan for the frame, initially, and the component layout, but to be honest, I often find that trying to design everything all at once leads to designing myby Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
Finally made it back into the shop to pick up where I left off. I know it's been a while, but.... The electronics in this printer need to be kept cool as the build space is being kept hot, so air handling is important. Here's a pic of the current state of the covers for the PSUs, and electronics. As you will soon see, once these are installed, they function to use outside air for cooling. I willby Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
Well, I had a meeting with the rep yesterday regarding the heat bed for my printer. Needless to say, this is not going to be cheap, but I do get the ability to determine what I want for warm-up time, etc. The ultimate design for the heat bed will incorporate the heater, plate and insulator into a single assembly for optimal reliability. I'm just days away from customer work being done, albeit briby Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
I'm looking at those and now the price I got for mine seems not that far off. I'm doing 18" x 28" and inch per inch, the pricing seems close. Guess I'm going to end up having to bite the bullet. At least I've been making money this month. I'm also checking into having the heater made up built right into a machined flat aluminum plate, though I don't yet have a price for that option. Also, the oneby Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
Sorry for the disappearing act, guys... I've been working 15 hours a day on a customer job for about the last several weeks and I'm putting the final touches on his job tomorrow. That means back to work on the printer. I hope to make some progress in the next week or so, and I will be keeping you updated as soon as things start to happen.by Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
CNC, you've given me a really good idea, but I am going to have to explore it further before I tell you what it is. I have been working on customer projects feverishly, and plan to return to work on my printer and to posting within the next couple of weeks.by Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
I have yet to lose hope that I can find what I want a bit cheaper, right now parts count is not so much of an issue, but when the time comes to duplicate this machine then it becomes rather important. Add up all the bolts etc, and the frame has well over 100 parts. The machined version will likely have around 20. So I would rather do the work up front to come up with a heater that is reproducibleby Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
Well, I had figured that since QUBD was selling a 12" x 12" for around 60 bucks I should be looking at no more than $200. However this particular supplier wants $475 for the first one, 300 bucks after that. Before I decide to go with them or not, I really want to check other options.by Maxx Mayhem - Reprappers
Re: Digital Calipers - 12 years ago
You basically have 2 choices - Good ones or cheap ones. The cheap ones are all about the same - some have been sitting around a long time, so suspect batteries first. I believe all can be zeroed. If you want to calibrate at extension, you can buy gauge block sets from a variety of sources at a variety of prices, depending on the amount of accuracy you need. I'd not suggest a $600 gauge block setby Maxx Mayhem - Reprappers
Re: Design nearly done - construction started... - 12 years ago
I've been a bit busy for the past couple of weeks servicing one of my primary customers, but over the weekend I did have an opportunity to fabricate the deck plates for the electronics. (deck plates for the electronics - really?) This is all a part of temperature control for in this case - the electronics. There will be covers for the PSUs which slant toward the back to vent via the slots in theby Maxx Mayhem - Reprappers