My Replikeo Prusa i3 Rework Build

I ended up placing a stack of paper under the frame. I guess when I get the printer running I'll print some stands instead.

Should have told you, pick up a pair of flush cut cutters while your there. Worth every cent clipping supports off and the end of the filament to feed it.

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underthetire
Should have told you, pick up a pair of flush cut cutters while your there. Worth every cent clipping supports off and the end of the filament to feed it.

Me? No worries, I picked up that tool set I linked earlier. It has a few pair of cutters. I'm still stuck on this damn endstop problem. I was able to gently pry the wiring assembly up a little bit to get the heads of the m3 screws under it, but the endstop on the x end idler is still a little wobbly. I may see if I can sink some nuts on the end of the screws to tighten it down.

My M5 nuts that drive the Z-axis were loose and the idler-size slips once in a while when I'm dropping Z- from a height down to home. Fortunately there's no visible effect on printing because it builds from the bottom up. I've printed a new idler with a x-belt tensioner but I've yet to install it. I had all sorts of odd print quality issues that turned out to be almost entirely due to a too-loose x-belt.

I'll be buying some spare endstops soon and they WON'T be this stoopid design.

Oh, and in a few spots you're probably have to cut some of the M3-14 bolts down to about 12mm. Do yourself a favor and put a nut on first, then cut, and use the nut to help clean the threads.

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gadget_greg
My M5 nuts that drive the Z-axis were loose and the idler-size slips once in a while when I'm dropping Z- from a height down to home. Fortunately there's no visible effect on printing because it builds from the bottom up. I've printed a new idler with a x-belt tensioner but I've yet to install it. I had all sorts of odd print quality issues that turned out to be almost entirely due to a too-loose x-belt.

I'll be buying some spare endstops soon and they WON'T be this stoopid design.

Oh, and in a few spots you're probably have to cut some of the M3-14 bolts down to about 12mm. Do yourself a favor and put a nut on first, then cut, and use the nut to help clean the threads.

There HAS to be a better x end idler model out there that will fit properly. Once I put this together and learn more of how it works installed, I may even take a stab at designing one just so people who have the stupid sainsmart end stops like we do can use them without the same headache I got mounting them to the idler and motor. Haha.

Honestly, these 14's don't seem like 14's. I measured them with my digital caliper (that I got for 9.99! Haha) and they're more like 12. I have literally like one thread past a flush nut on the x end idler and the instructions said to cut that one. If I do run into that, though, I'll definitely put a nut on first then take a dremel to the bolt.

I had no issues at all with either x belt tension or the end stop. Y end stop on the other hand never did fit right.

A couple of the motor bolts needed to be shortened IIRC.

PS, I went to Harbor Freight again today too...

Oh, and if you haven't figured it out yet just (carefully) bend up the connector on the endstop to get the screw heads in there, then bend it back down.

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gadget_greg
Oh, and if you haven't figured it out yet just (carefully) bend up the connector on the endstop to get the screw heads in there, then bend it back down.

@underthetire - I haven't done the belt yet. I've barely started. I did manage to finally get the ball bearings into the x idler and x motor, that took a while because I was afraid I was going to snap something. Good to know the pieces are fairly durable Then I ran into the problem where I didn't know what the hell size bolts were what because nothing is labeled Trial and error, and comparing sizes against the BOM helped with that. Then I got to the problem with the M5 nuts in the idler and motor and just heated them up and press fit them - that worked. Finally ran into the problem with the endstop. It seems *okay* but I'm not crazy about how it looks. It's fairly tight. It has a little wiggle room, but you need to put pressure on it to really shift it at all.

@gadget_greg - Yea, that's what I wound up doing. It's still sitting at an ugly angle, but the connector fits in it just fine. I can't get the screws any lower. They are as flush as they can get but they still raise the connector. Hopefully it'll be fine. Pics attached.

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gadget_greg
A couple of the motor bolts needed to be shortened IIRC.

PS, I went to Harbor Freight again today too...

Haha sometimes it's worth the trip

Our last kid leaves for college on Wednesday, had to hit BestBuy for a couple laptops (her sister needs one for med school too), so I figured while I was in town (Albany)...

All of our endstops look like that. It IS a poor design. When I buy spare endstops they will definitely be a better design.

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gadget_greg
Our last kid leaves for college on Wednesday, had to hit BestBuy for a couple laptops (her sister needs one for med school too), so I figured while I was in town (Albany)...

All of our endstops look like that. It IS a poor design. When I buy spare endstops they will definitely be a better design.

Can I be adopted? Haha. Damn, a kid in med school and a couple of laptops, no big deal. I think I need to leave Long Island. LOL Congrats, though. You must be doing something right.

Yea, it looks like Replikeo uses the cheaper Sainsmart ones. The build instructions warned about them, but I guess that's what we get. I bought the Sainsmart brand LCD/SD Card Reader. I hope it's not as badly designed. At least it's reassuring to know that I installed it correctly and that's just how they are.

I'm not even employed right now. Hopefully the $$ doesn't run out. :/

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gadget_greg
I'm not even employed right now. Hopefully the $$ doesn't run out. :/

I hope your daughter graduates med school early and returns the favor, then. Haha. I wish you luck, either way.

Okay, on topic - I'm assembling the x-carriage. That digital caliper I got only goes to 6 inches. What's the best way to measure that I have the motor and idler precisely 362mm apart? Also, it doesn't matter which end I shove in deeper, correct? Um... that sounds wrong. I mean it looks like both parts will accommodate the rods. Does it matter which side has the rods going deeper into it provided it makes 362mm?

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LittleMike
I'm assembling the x-carriage. That digital caliper I got only goes to 6 inches. What's the best way to measure that I have the motor and idler precisely 362mm apart? Also, it doesn't matter which end I shove in deeper, correct? Um... that sounds wrong. I mean it looks like both parts will accommodate the rods. Does it matter which side has the rods going deeper into it provided it makes 362mm?

For me I just adjust it till it matches the holes on the z motor mount (where the z smooth rods are supposed to be).

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alvinhochun

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LittleMike
I'm assembling the x-carriage. That digital caliper I got only goes to 6 inches. What's the best way to measure that I have the motor and idler precisely 362mm apart? Also, it doesn't matter which end I shove in deeper, correct? Um... that sounds wrong. I mean it looks like both parts will accommodate the rods. Does it matter which side has the rods going deeper into it provided it makes 362mm?

For me I just adjust it till it matches the holes on the z motor mount (where the z smooth rods are supposed to be).

I started with the X-axis, so I don't have a Z-axis assembled to line it up with. On a side note, it does appear that the rods go pretty much all the way in at around the 362mm mark. Does it *have* to be precisely 362mm or is it just a matter of it has to line up properly?

I just used a ruler for that. Get's ya' "close enough for government work".

I didn't measure either. Left everything loose and just made sure there was no binding when moving the carriage up and down on z.

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gadget_greg
I just used a ruler for that. Get's ya' "close enough for government work".

I'm definitely familiar with that one. Haha my friend David says it best - it's not just good, it's good enough.

362mm = 14 1/4 inches. I'll just measure approximately that.

A little hard to tell from the pic, but looks good to me.

The ultimate goal is get it to run smoothly on the z-axis rods so you may still need to adjust it a bit before inserting it into the z-axis rods. Don't waste too much time on this without the z-axis.

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alvinhochun
The ultimate goal is get it to run smoothly on the z-axis rods so you may still need to adjust it a bit before inserting it into the z-axis rods. Don't waste too much time on this without the z-axis.

Understood. I think that will be tomorrow. If nothing else, it'll be a good baseline and I can adjust from there.

Don´t worry about 362mm between X motor and idler. You can´t do it bad, because Z smooth rods will not let you have more or less than 362mm + tolerance.

Just try push X carriage with hand, if you feel force or friction it is not good, if you don´t then it is OK.

About M5 nuts for Z-axis: I put them in slot with some lubricant. They are holding there good and it is fail-safe how to not break HB when your print head hit it due to some failure (bolt pops out of slot and printhead will stay sitting on HB )

Edited 2 time(s). Last edit at 08/17/2014 08:08PM by Allnei.

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Allnei

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Bratan
Guys two more question.

First, I noticed when I printed my big gear, that every level shifts slightly to the right (in X direction). What could be causing this?

Second, I've been having this annoying issue with Repetier since day 1. When I'm doing second print, it will stop heating up HotEnd. It says it's own, and I think even LED light is on but Hotend is cooling down. If I reset the board and reconnect, it starts working again. Anyone seen this issue?

Check your X and Y belt tension and friction, I had similar problem when I was doing something on X carriage and put some force on it.

Finally had a chance to work on the printer. I redid X belt, made it as tight as possible. Y axis belt is good.
I also adjusted Z-axes, it was a little uneven. I'm still having issue tho
To demonstrate I'm attaching pictures. First 2 pics show shift in X axis (left side and right side), last one shows shift in Y axes. What could be causing this?
As for my issue with Repetier, I figured it's a bug in program... I left it be and noticed that it first heats up bed, then it homes all axes and only then it starts heating up extruder. Stupid, it should heat the in parallel, but I can live with that

Edited 1 time(s). Last edit at 08/19/2014 05:03PM by Bratan.

It is not stupid, if you heat HB (15-20min) in same time as HE (1-5min) then filament in HE will be destroyed due to high temperature for long time without extruding.

For your problem with shift, try to to send more power to motors.

Edited 1 time(s). Last edit at 08/19/2014 06:02PM by Allnei.

I agree with more power, also make sure your slides move freely. Without belts they should take almost no effort to move them. Make sure your hot end is tight in the extruder body as well.

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Allnei
It is not stupid, if you heat HB (15-20min) in same time as HE (1-5min) then filament in HE will be destroyed due to high temperature for long time without extruding.
For your problem with shift, try to to send more power to motors.

I guess it makes sense, but printing process usually takes much longer than HB heating.

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underthetire
I agree with more power, also make sure your slides move freely. Without belts they should take almost no effort to move them. Make sure your hot end is tight in the extruder body as well.

Thanks, I'll try adjusting those POTs to give it more amps

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Bratan

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Allnei
It is not stupid, if you heat HB (15-20min) in same time as HE (1-5min) then filament in HE will be destroyed due to high temperature for long time without extruding.
For your problem with shift, try to to send more power to motors.

I guess it makes sense, but printing process usually takes much longer than HB heating.

Yes, but the filament isn't staying still during printing, it's constantly being pushed through, so it's only melted, not burnt.

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MakerFarm 8" Prusa i3v
RAMPS 1.4
0.4mm E3D v6 for 1.75mm

Okay, so build progress is being made. I'll post pics later. I do have a question, though. For the y-axis with all the M10 rods, nuts, etc. The build manual says 186mm from y-corner to y-corner. I've done that, but there is a good inch or so of threaded rod past the outside nuts if I do that. Is that okay?

If you look at the build manual here:

[reprap.org]

scroll all the way to the bottom photo. There is hardly any threaded rod beyond the outside nuts. If I bring it all down to 186mm on the lateral faces (longitudinally) then I have all that extra sticking out. If I *don't* thread it down that length, then the smooth rods don't sit right on the corners because the gap is wider than they are long. At 186mm, they sit perfectly. Should I just ignore the extra length of threaded rods coming out of the corners? I could always cut them, I guess, or leave them if they don't matter.

The excess is not a problem, the whole idea is that the smooth rods are parallel, at the same width on both ends, and the same width as the linear bearings attached to the heated bed mount. You can keep them slightly loose until you get the bed moving smoothly then tighten them up.

I ended up replacing my upper threaded rod on the back end with a 5/16" (or was it 3/8"?) rod that was a couple inches longer so I could install the z-stabilizer that Tech2C posted earlier in this thread. It works great! [forums.reprap.org]