Reinforced 3 bolt Y axis motor mount
I don't want to beat a dead horse but I thought this was necessary. https://www.thingiverse.com/thing:2809788
I read a lot of comments from people asking if a third screw was able to be added to the motor mount so I decided to go back to the model and investigate this. I fount that I was able to do so easily by adjusting some bolt lengths and tweaking some features on the original motor mount.
I originally didn't want to reprint the motor mount due to the .5mm offset that is standard on the printer since this is a minimal error and is probably negligible. However since I had to make the mount more rigid as well as add the third bolt, I figured I would correct this misalignment in the process.
This mount is intended to be used with the stock belt holder only. With this mount there is no longer any misalignment of any type. I also added 1.5mm to the face of the mount so that the motor was moved to the side. This places the motor shaft in the proper location so that the pulley is centered on the shaft. This gives an even amount of side to side adjustment of the pulley location. so there no more issues with belt rubbing due to a lack of pulley adjustment. This also pairs nicely to the adjustable belt tensioner that I designed ( https://www.thingiverse.com/thing:2786671 ) and with this combination along with the stock belt holder, there is perfect belt parallelism as well as no belt misalignment.
Unfortunately in adding the third screw, some hardware must be replaced from the stock setup. You will need two m3 x 30mm socket head cap screws and one m3 x 16mm (longer wont hurt) socket head cap screw. All the other hardware remains the same. See the assembly drawing for screw locations.
Thank you again to jweaver for testing as well as the pictures!!!
Re: Reinforced 3 bolt Y axis motor mount
Loving the mount.. I was really happy with RHDs "re-enforced" version.. But Matthew then had some ideas on how he could improve.
Since I was already using his belt tensioner, I decided to take a look.. And glad it did.. Its beefy for sure, with no chance of flex.. And the extra hole means the motor is mounted much more securely (motor mounts with 3 bolts, rather than 2).
The only down side is that it needs a selection of different length screws, but most of these can be found in the spares bag.. And those you don't have, could be cut down with a hack-saw from the longer ones, rather than buying them..
Good work Matthew... Looking forwards to seeing what else you come up with.
Re: Reinforced 3 bolt Y axis motor mount
Loving the mount.. I was really happy with RHDs "re-enforced" version.. But Matthew then had some ideas on how he could improve.
Since I was already using his belt tensioner, I decided to take a look.. And glad it did.. Its beefy for sure, with no chance of flex.. And the extra hole means the motor is mounted much more securely (motor mounts with 3 bolts, rather than 2).
The only down side is that it needs a selection of different length screws, but most of these can be found in the spares bag.. And those you don't have, could be cut down with a hack-saw from the longer ones, rather than buying them..
Good work Matthew... Looking forwards to seeing what else you come up with.
Thank you Jon for the kind words and for your help in testing these parts and providing me with feedback to tweak the designs. And yes I will definitely have more goodies to come.
Re: Reinforced 3 bolt Y axis motor mount
Props to you @Matthew.v8. I started with your Y-Axis belt tensioner and really appreciated the fine adjustment I was able to achieve. I ended up printing the motor mount last night and like it equally well. My pulley is now sufficiently far away from motor face and though my belt still walks side to side it doesn't rub the pulley walls on either end of the stroke.
Re: Reinforced 3 bolt Y axis motor mount
Props to you @Matthew.v8. I started with your Y-Axis belt tensioner and really appreciated the fine adjustment I was able to achieve. I ended up printing the motor mount last night and like it equally well. My pulley is now sufficiently far away from motor face and though my belt still walks side to side it doesn't rub the pulley walls on either end of the stroke.
Thanks Edward!! Glad you’re happy with the designs, a lot of time went into making sure they were the best possible! Glad your pulley is running true and that your adjustment is nice and precise.
Was it hard finding the hardware for it?
Re: Reinforced 3 bolt Y axis motor mount
..
Was it hard finding the hardware for it?
No I used a combination of spares and cap screws purchased on Amazon earlier... I like to have spares on hand. One thing to keep in mind if you do anything that requires square nuts. Prusa uses thinner nuts than are commonly available and there are only a couple extra square nuts in Prusa's provided spares.
Re: Reinforced 3 bolt Y axis motor mount
..
Was it hard finding the hardware for it?
No I used a combination of spares and cap screws purchased on Amazon earlier... I like to have spares on hand. One thing to keep in mind if you do anything that requires square nuts. Prusa uses thinner nuts than are commonly available and there are only a couple extra square nuts in Prusa's provided spares.
I did notice that they use the really thin hex nuts. I try to, where I can, design a deeper hex hole to use a wider nut or a nylock.
Re: Reinforced 3 bolt Y axis motor mount
Well here is my take on the Y axis motor mount.
My existing mount showing the problems with it
I probably have the belt slightly over tight that is bending the bracket but still.
My Version Of the Mount
It starts roughly the same as Mathew's design only that the motor is in the Prusa designed position. Rather than move the motor hard against the rear frame member a brace is run under the motor to its far end and this presses against the frame. Resulting in the original motor clearance tolerances being retained but still bracing the motor from twisting around the Z-Axis.
The New Mount Fresh Of The Press
Finally Fitted To The Printer
Martin Wolfe
Re: Reinforced 3 bolt Y axis motor mount
Well here is my take on the Y axis motor mount.
Ahh, I like the anti twist bracket, that’s smart. We haven’t see any twist in the motor mount since it’s so darn thick as well as the fact that it banks up to the frame. I did however come up with a secondary mount. If there is any flex (highly doubtful), this will DEFINITELY eliminate it-see the attached picture.
It uses two of the motor mount screw locations in the rear as well as one screw into the 3030 rail. I felt this design was unnecessary since I placed the motor up against the frame, if there is any twist it will only twist the motor into the frame (it has no where to go) and stop there.
P.S. if you’re having belt tensioning issues, you can check out the tensioner I made for the y axis. It’ll help fine tune the tension as well as keep your pulley at the proper height to maintain parallelism in the belt holder. https://www.thingiverse.com/thing:2786671
Re: Reinforced 3 bolt Y axis motor mount
The mount was the most urgent thing to do. I'll be seeing to the idler when I do a full strip down to put in the R2 parts.
Martin Wolfe
Re: Reinforced 3 bolt Y axis motor mount
The mount was the most urgent thing to do. I'll be seeing to the idler when I do a full strip down to put in the R2 parts.
Nice. You can see by those pics that the third screw is necessary.
Re: Reinforced 3 bolt Y axis motor mount
The mount was the most urgent thing to do. I'll be seeing to the idler when I do a full strip down to put in the R2 parts.
Hey Martin,
I am new here, I just got my Prusa i3 mk3 kit yesterday and decided to give it a go: sadly my Y-motor mount decided to "eat" one of the nuts and it wont allow me to remove it anymore as it is spinning in place. I screwed one bolt into the bracket to pull the nut into its hole and that i cannot remove now without damaging it further.
I stumbled upon this post and I saw your upgrade. I was wondering if by any chance I could ask a Prusa brother to print one for me as well (for whatever reasonable price) - this is my only printer so I cannot really print one myself, else I would.
Thank you kindly!
David.
Re: Reinforced 3 bolt Y axis motor mount
Hi David,
Where are you located?
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Re: Reinforced 3 bolt Y axis motor mount
Hi David,
Where are you located?
regards Joan
Hello Joan,
Thank you for your speedy reply.
I live in Georgia, USA. - used to be a Brummie, but my wife decided to do uni in the US.
Regards
David.
Re: Reinforced 3 bolt Y axis motor mount
Thanks David,
Ah, that's a bit far for me to send you a part...
Hopefully there is someone nearer you who can help.
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Re: Reinforced 3 bolt Y axis motor mount
with a tiny flat blade screwdriver like a Whia try to jam the spinning nut on its outside flats; that should help you get the cranking screw out then you can try supergluing it in place so you can continue the assembly
Re: Reinforced 3 bolt Y axis motor mount
with a tiny flat blade screwdriver like a Whia try to jam the spinning nut on its outside flats; that should help you get the cranking screw out then you can try supergluing it in place so you can continue the assembly
Thank you for your suggestion.
The screw and nut got stuck in the y-motor mount before attaching it to the frame (I was trying to pull the nut in, remove the screw and then attach the mount to frame).
Anyway, thank you all for your input. I ended up using a Stanley knife to cut 1/3 of the mount corner off (the countersink part- as a result, the nut was no longer inside the part, but sitting on it) and when i attempted to remove the nut by gripping it with a wrench, the screw actually snapped in two- no way I would have been able to remove it just by prying it with a screwdriver.
I successfully mounted the motor to the frame and all is well. Once I have the printer running I will print the upgrades and replace the system.
Thank you again!
David.
Re: Reinforced 3 bolt Y axis motor mount
Joan- Thank you for taking the time.
William , If you see this, thank you a tonne for your private message. You are a true Prusa-brother : 😛 - I am not allowed to respond to private messages as I have not participated in the required amount of posts yet. I wrote in a reply above: I think I will be able to print it myself once I finish the installation. (I asked for help because I had lost hope, but then I remembered I had nothing to lose, so i gave it another try and 'fixed' it) The belt seems to be tensioned properly and the motor rotates around its axis minimally (I presume that is why the rev1-3 upgrade).
Re: Reinforced 3 bolt Y axis motor mount
Hi David,
I hope the printer works well for you
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Re: Reinforced 3 bolt Y axis motor mount
Joan- Thank you for taking the time.
William , If you see this, thank you a tonne for your private message. You are a true Prusa-brother : 😛 - I am not allowed to respond to private messages as I have not participated in the required amount of posts yet. I wrote in a reply above: I think I will be able to print it myself once I finish the installation. (I asked for help because I had lost hope, but then I remembered I had nothing to lose, so i gave it another try and 'fixed' it) The belt seems to be tensioned properly and the motor rotates around its axis minimally (I presume that is why the rev1-3 upgrade).
Sorry, I forgot about the private message limitations for new folks. Glad you got unstuck. A note on belt tightness. I found, at least for me, that when I had the belt, what I thought was appropriately tightened, I was actually too tight. I ended up significantly loosening my Y belt. I need to do the same on the X belt, but I don't want to take it apart as it is printing rather well, even in its current state.