I’m new in the world of 3D printers, and this is the first I’ve build so far. At this point it runs just amazingly well.
BUT there’s 1 thing that bothers me a little and that’s the belt grinding against each-other. I tried to angle the motor in pretty much every position and also moving the pulley on the rod. But it seems pretty much impossible to get rid completely of the grinding.
SO as it seems this is going to be under the category normal “wear and tear” of this printer, I went looking to get some spare ones to have them laying around just in case they fail.
But the web-shop I ordered my printer from (Conrad) doesn’t have these in their store. So looking elsewhere I didn’t really find anything suitable, apparently the size of the 4 long ones are not a standard length whatsoever.
SO my question is: Does anyone know how or where to get these? I was thinking buying a open belt and making some sort of clamp to close them. But the 180 ones I need to buy closed at length.
EDITED: I first said “But the 150 ones I need to buy at length” edited this to 180 which is the correct size.
Kind regards!
JeAfKe
Yeah, those are pretty much what I had in mind.
I’m now in conversation with conrad, and see what they are priced.
If they are reasonable priced I’m just going for the original onces.
Another idea I had in mind was this:
Would buying another pully and grinding this off to only 7mm at the toothed part, and mounting this behind the allready existing one so there’s a disc between both belts thus avoiding the grinding.
Here’s a little photoshop that makes it more visual. (Actually ps’ing the 180 belt is to much work, but I’m sure u get the idea)
Your gonna end up with Another issue and that is that the buildspace will become smaller and your going to have to move the homeing 0 coords because the home position will be moved on the other axis or the blocks will hit the pullies.
[quote=“SlowFoot”]You can cut down both pulleys and print a washer to put between them. no problem with the space then.
And use a hacksaw, No fun grinding aluminum and potentially dangerous if you don’t have the right equipment.
[/quote]
YES! 5 minutes after I posted that I was thinking the exact same!
[quote=“SlowFoot”]…or, sheep n’ dirty, print a washer that fits the teeth of the pulley and an end stop washer with set screws for 8 mm shaft.
Remove the pulley’s flange on the “outer side”, put the washer on the wheel and then use the end stop washer to replace the missing flange.[/quote]
Nope didn’t came up with this idea, but it sounds like a Awesome idea!
Only thing is… I don’t wanna test this on a “Good” pulley since I don’t got any spares…
But if some pulley ninja could test this maybe? Or already done something similar I would really appreciate sharing some info and ideas here!
BTW. @Velleman
Next time when U copy something, make sure to copy the good ideas to… The “donor device” uses 2 separate pulleys, which is superior if U can get them to grab the rod really tight… On the other hand I do get the idea of having it on the same pulley and that way removing most risk of having the “driven” pulley to start slipping… flic.kr/p/avb6bA
All looks damn familiar, but the case of the vertex looks way nicer imho… flic.kr/p/avbbFq
Yeah well seriously, Y axis runs really smooth no rubbing whatsoever…
X axis seems to be impossible to get rid of… So what I tried today.
-swapped Pulleys on the “Driven” Rod (Maybe the one used wasn’t straight…) => No change.
-Moved the Pulley on the stepper motor 1mm more outwards. (I really hoped this would do the trick) => No change.
-Angled the stepper motor so the belt would “Ride Upwards” and move outwards => No Real change… Belt doesn’t want to go upwards!!!
-Applied more tension on the small belt so its “forced” to move upwards => Yes almost no grinding, but TERRIBLE jerky movement (seems to come from the minimal oval shape of the pulley mounted on the rods/stepper in combination of the higher tension on the belt. Explanation of my “oval” idea: The pulley’s bore is bigger than the rod it goes over so by fastening the m3 set-screw the pulley is not exactly centred any-more… Makes sense right?)
NEXT ideas I had:
-What’s the ideal belt position inside the clamp vellemans manual says “Now move all the pulleys in such a way the belts sit in a straight line from pulley -> carriage -> pulley.”
That doesn’t really look straight to me… Or do I need to get some glasses…
So could you give me an exact picture from the top of your correctly 0 grinding machine, or take some measurements of distance the pulleys flanges are away from the back plate and the exact amount the belt is inserted inside the clamp?
Anyway thanks to everyone thinking about this issue and trying to help me out!
Well the picture of the “not so straight belt” is actually from the assembly manual… SO… IDFK anymore…
At this moment its reduced to a minimal “touching” U can still see the belt tilt a little when changing direction… But I guess eventually when they wear a little this will be reduced also.
The climbing I actually tried, but it needs to much tension on the small belt to actually achieve this, afterwards the movement is really jerky. Without putting tension on it, it doesn’t want to climb upwards.
Next thing I didn’t check is the actual width of the belts… Would be funny if one was lets say 6.2 mm instead of 6.
Is there any chance to order replacement belts (in Germany)? Mine rip up a little bit due bad alignment, still doing this, but very very little, but I guess I need new belts in a year or two.
I’Ve moved the pulleys from the stepper motor more away from the motor to prevent belt ripping, the belt is supportet by the the side of the pulley & “pushed” away from the other belt. But this only helps to 90%, some minor rubber dust is still there, so I assume they stillt touch each other sometimes.
Yes, I just ordered a complete set (6 belts) at conrad but you have to contact them trough the contact form to order them. Delivery time is 3 weeks. And a complete set is € 42,60 plus extra shipping costs to belgium (special orders like this always costs €6.95 to ship) so it’s a total of €49.55
Yeah I’m in the exact same situation, the black dust keeps coming. Mine is at its maximum inward position, when the end-switch is triggered there is about 1mm clearance between the pulley and the Y linear bearing clamp.
Yes, I just ordered a complete set (6 belts) at conrad but you have to contact them trough the contact form to order them. Delivery time is 3 weeks. And a complete set is € 42,60 plus extra shipping costs to belgium (special orders like this always costs €6.95 to ship) so it’s a total of €49.55
Yeah I’m in the exact same situation, the black dust keeps coming. Mine is at its maximum inward position, when the end-switch is triggered there is about 1mm clearance between the pulley and the Y linear bearing clamp.
Kind regards.
JeAfKe[/quote]
Was there a sparepart-number on it? Maybe this is quicker than explaining them what to want Thank you.
But eventually I ordered these Parts for K8400
[ul]
[]2 x (685mm x 6mm T2,5 BELT) € 9.30 per stuk[/]
[]2 x (670mm x 6mm T2,5 BELT) € 9,30 per stuk[/]
[]2 x (180mm x 6mm T2,5 BELT) € 2,70 per stuk[/]
[/ul]
[size=150]t2.5 19t pulley with 2 fastening flanges with 3 set-screws using a m3 nut.[/size]
Next thing I’m thinking of is adding a copper/metal ring with 3 holes to make the whole fastening part more rigid… Might this actually work?
Or will the PLA just compress between the metal ring and the m3 nut…?
Of course I’m not going to use those screws, I’m planning on using small 4mm set-screws not those long Pozidriv screws.
Anyone got experience with plastic pulleys? Worthless?
I might went a little overboard on the amount of pics
The problem might be that the pulley is too long. Had this while trying to avoid belt ripping by new aligning the pulleys, the Y endswitch couldn’t switch, the pulley was in its way and stopped the head before reaching the endswitch. So first hold it next to each endswitch (X & Y) and see if the head can reach them although.
It was more a print test, to see how it would look like, if the teeth would actually be smooth and such. I know its to long, but I’m gonna cut a piece of anyway.
Anyone have experience with plastic pulleys? I can imagine they won’t be durable as durable as the metal ones…
But I haven’t seen a t2.5 19t double with middle flange before in metal.
Found something interesting: maedler.de/Article/16021900
Small 6mm pulleys, it should be possible to use two to avoid the belt ripping. Drilling them to 8mm rods & attach a screw shouldn’t be a problem.
[quote=“jeafke”]Like the hole is 3mm standard.
It needs to get OVER a 8mm rod, so the hole should be 8.2mm Ideally?
SO my approach would be the following (If I had robbed a DrillBit store) The best chance creating an “centered” 8mm hole is this imho.
[ul]
[]Get 3.5mm DrillBit => Drill[/]
[]Get 4mm DrillBit => Drill[/]
[]Get 4.5mm DrillBit => Drill[/]
[]Get 5mm DrillBit => Drill[/]
[]Get 5.5mm DrillBit => Drill[/]
[]Get 6mm DrillBit => Drill[/]
[]Get 6.5mm DrillBit => Drill[/]
[]Get 7mm DrillBit => Drill[/]
[]Get 7.5mm DrillBit => Drill[/]
[]Get 8mm DrillBit => Drill[/]
[]Get 8.2mm DrillBit => Drill[/]
[/ul]
Result a 8.2 mm hole with the same center point as the 3mm hole. (I think, in my head this works perfectly but I’m no metalworker.)
Kind regards
JeAfKe[/quote]
That would not result in a straight hole.
The best solution would be drilling the hole in a lath. Drill a 7,8mm hole, and then a 8,00 - 8,02mm hole with a special precision drill. (called a “Rival” in Danish)
Second best, jump straight to 8mm and drill.
When you predrill, normally you jump 3x in size. Så the 3mm predrilled hole can be bored up to 9mm directly.
Drilling to 8mm is not that difficult to me, could get the maschines for it, worked in a machine shop before
Usually we did a small hole completely through the object, than a one which is slightly smaller than the final one. The final one with reduced speed & you get a perfect hole (this requires very good drills!!!). 8,2mm would be to much, 8,0mm & if necessary sanding/polishing it tiny bit bigger, but usually it fits on 8mm rods, they seem to be a little smaller, guess 7,995mm or so.
Thank you.
