Breaking frame screws fix suggestion
Hi
Excited to build my new i3 MK2s
I'm not superhuman. But I still broke 4 screws in the frame at Step 3 "Screw Z-axis-bottom parts to the frame". I tried to be gentle but it needs a very exact level of force which requires prescrewing the screw with a better tool than the small key supplied.
So going into my toolbox and getting the hang of it. Right side is now secured with 2 screwed. Left side is hot glued for now. Don't have a drill to drill out the screw part. I got confidence in the glue.
However. How about in future kits, change it to use washers and bolts instead?
Would same some hazzle I think. As other people are also experiencing the problem:
Otherwise I'm still excited about assembling the rest and start printing. Just gonna be extra carefull when it comes to screwing into the frame. Maybee look into using bolts instead..
The kit is still Awesome!
Re: Breaking frame screws fix suggestion
What about try this: http://manual.prusa3d.com/Guide/4.+Z-axis+assembly/296 and insert screws from oposite side?
Re: Breaking frame screws fix suggestion
Only question that I have is "how". 😯
Re: Breaking frame screws fix suggestion
Not a huge help for you now but I ran a tap through all the threaded holes as it looks like the frame is coated after it is tapped.
You might be able to remove the 2 protruding screws by putting a little easing fluid on them and then doing a drill chuck up on them nice and tight and then reversing the drill to get them out. Beware trying to drill them as stainless steel is a pig to drill at the best of times. Good luck.
Re: Breaking frame screws fix suggestion
Just tried it on the top on the opposite side..
I can see the threading a bit more clearly on the opposite side. But it seems like 50-70% of the threading has coating stuck in the grooves. And clearing it with a screw is still tricky.
Just been looking at prices for a tapping set including a M3 tap to clear out the threading. Which I might just get.
I'm just guessing, but I suppose the frame is coated after threading the holes which is causing the problem. If the treading was done after coating I would suspect them to be clear. But that proberly complicates the whole process of manufacturing the frames as an extra step after coating is required.
Again bolting just seems simpler as threading of the frame wont be required at all then. But I can see it will look more clean with screws... so I'm going to buy a M3 tap hehe... it could come in handy in the future anyway...
Re: Breaking frame screws fix suggestion
1 screw, 1 broken. Was getting tight, so I reversed it out, lubricated hole and re-screwed. It still broke with .5mm to go. It broke flush, so drilling only way out, but as previously mentioned, my drill won't touch it, so I am stuck!
I am not prepared to risk any more screws, so looks like buying an M3 tap is the only way forward.
I cannot believe that all non-tapping assemblers don't have this problem! Do Prusa pre-tap before assembly? If so, I would have preferred a tap and wrench be included with the kit instead of the Haribo. Controversial, I know.
Anyone else overcome this without tapping?
Re: Breaking frame screws fix suggestion
at my kit, that arrived late november last year, i've had the same problems. holes/threads simply were to tight.
maybe they coat the parts like z-frame & y-carriage after drilling - and in case of the z-frame: tapping - the holes ?
fortunately i've had the required m3 taps at hand (only requried the one for the finish)....
tip: have a look at the holes of the y-carriage as well. there the screws that hold the printbed in place should go through the material without any threads !
otherwise you will squeeze the printbed while assembling it. and if the holes of the y-carriage and the standoffs from the heatbed are not 100.00% aligned, you may run into trouble keeping the print surface as flat as unassembled.
at my kit i've widened the y-carriage holes with a 4mm drill, so that there is a little bit clearance in x/y direction and nothing "squeezes" the printbed into place.
dem inscheniör is' nix zu schwör...
Re: Breaking frame screws fix suggestion
Thanks, JeffJordan, problem is, being in rural Australia, buying an M3 tap is nigh on impossible. M4 was the smallest I could find, and that was in a set costing AUD$69.
Today, I intend doing a 2hr round trip to the next town, but still not confident. With Auspost, I can expect to wait for about 1 1/2 weeks, if I order online. I CAN'T WAIT! Sorry!
If I drill out the holes to 3mm and use M3 bolts with nuts on the back, will the nuts interfere with anything? (Looks like they will foul PSU).
Re: Breaking frame screws fix suggestion
You could make your own hole cleaning tap. Just take a small file and file a notch in the end of one of the screw.
Re: Breaking frame screws fix suggestion
I managed to buy an M3 tap. Surprised at how tight even tapping was. Drilled holes with tapping drill 2.5mm and made life easier, but still produced a lot of swarf for pre-tapped holes. i3 now built and first print done!