MakerFarm 8" i3v Prusa build by Printbus

[printbus]

Is something like this what you were talking about? http://www.amazon.com/LM7805-Termina.../dp/B00NCKUWE4

Yes, that's an example of a fixed regulator that could be connected to the existing 12V power supply. This is still a linear regulator and will dissipate heat. There's at least a small heatsink on the 7805 part to help with that.

The BEC/UBEC mentioned by TopJimmyCooks is a common thing in the RC hobby. BEC stands for Battery Eliminator Circuit. They are a switching type of regulator more efficient in taking just about any voltage input and providing a fixed output. FWIW, our printer application would use a BEC that can accept 3S voltage input. In RC, each "S" is nominally 4.2volts, since that's the full-charge of a LiPo cell most often used in modern RC batteries. Motors can run on up to 12S (48V) batteries, and a BEC is commonly used to power electronics that require a lower fixed voltage off that same battery, eliminating what used to be a separate battery for just the electronics.

Did you ever notice your 7805 getting hot? It could be that it was having thermal issues running without a heatsink. Linear regulators can overheat very easily. I won't bog this with the math details, but at 12V input a typical TO-220 package 7805 regulator without a heatsink will be going into thermal shutdown with just over 300mA of constant load connected to it.

[AbuMaia]

YDid you ever notice your 7805 getting hot?

No, I didn't notice. I don't think I had it installed more than 10 minutes before I removed it after the servo went nuts.

[usarmyaircav]

Putting together the extruder, it looks like I stripped out one of the m3 x 25 and a m3 nut. Will I be able to find those at my local Lowes, or do I need to get it from Makerfarm or the internet?

[printbus]

Putting together the extruder, it looks like I stripped out one of the m3 x 25 and a m3 nut. Will I be able to find those at my local Lowes, or do I need to get it from Makerfarm or the internet?

Bummer! I have found Lowes and HD to be very spotty as far as metric hardware. They have some, but not much - especially as you get smaller in size like an M3. A lot of RC Hobby stuff is metric, so if you have a pretty good RC shop in the area I'd try that. The newer Ace Hardware stores have an extensive hardware section as a way of drawing customers in; that's where I usually go when I need something. I can't speak to the 25mm length though - that's getting pretty long as far as M3 hardware. Going on-line is always an option - I've done that when I need a quantity of something and the single piece price at Ace would make the cost outrageous. There are some sellers on eBay that have pretty good prices on say quantity of 50. Just be sure you're buying from a state-side seller. A possible advantage of MakerFarm is that they might just send you the hardware as a courtesy.

Between RC and the printer, I've also bought from multiple online companies like Bolt Depot. Shipping tends to be a killer compared to the hardware cost (most seem to all charge priority mail as a minimum rate). I do usually have a list of hardware spares I could use, and when I need something I dig out the list and see what else I can order. That helps make me feel better about having to pay a lot for shipping.

Good luck!

[printbus]

Wait. On the extruder? Are you talking about the long screws used with the guidler plate that pivots? They're longer than 25mm and I believe can be hard to find. Just not sure where else there's an M3 with a nut on it.

[jtice]

Putting together the extruder, it looks like I stripped out one of the m3 x 25 and a m3 nut. Will I be able to find those at my local Lowes, or do I need to get it from Makerfarm or the internet?

ACE HARDWARE !
They are great for these odd metric bolts, nuts, etc.
WAY better than Lowes and HD.

[TopJimmyCooks]

Lowes and HD use the same hardware suppliers and they bottom out hard at 4mm. might be able to get a 3mm nut there. Ace is a little better but can be inconsistent as well. I think they restock their metric bins bi-annually whether they need it or not. Also, longer sizes are rare everywhere. I ordered a bunch from mrmetric.com. No minimum order of any sizes, just a $6 flat rate shipping fee.

[printbus]

Yeah, mrmetric is good. I've bought a lot of stuff from them as well. My pool of hardware suppliers also includes jrhobbyhardware, microfasteners, rtlfasteners, and rcscrewz. When I'm looking for the miniature RC stuff, I rarely find everything I need at one place.

[usarmyaircav]

Hi, yeah the two bolts that have the springs for the extruder. I thought I had measured them but will take a look again. I will check both Ace and Lowe's, however I am in a small town so not sure of there stock. Tulsa might have a hobby shop, or I will order from mrmetric. I am so frustrated to be sooo close. I will move on to everyone every thing else I can do.

[printbus]

Hi, yeah the two bolts that have the springs for the extruder. I thought I had measured them but will take a look again. I will check both Ace and Lowe's, however I am in a small town so not sure of there stock. Tulsa might have a hobby shop, or I will order from mrmetric. I am so frustrated to be sooo close. I will move on to everyone every thing else I can do.

Those guidler spring bolts are 50mm long, probably the worst bolts on the i3v you want to have to look for. My guess is you'll be having to get those online somewhere. Another option would be to look at swapping out the M3 for #4 x 2-inches. Even that can be tough to find. #6 might require drilling out the screw holes, and you'd likely have to look for small-size #6 nuts to have them fit in the nut traps.

FOLLOWUP COMMENT: Glancing at eBay, I see a number of RC and hobby-type sellers offering M3x50mm cap screws. That's a sign that they might be easier to find than I initially thought.