Space wrench!

You may have missed it in the news but NASA recently sent up a ratchet spanner to be printed on the international space station rather than wait the 6 months or so to get one up on a supply rocket.

Story is here,

Well NASA were good enough to release the STL file for the print and I couldn’t resist giving it a go :smile:

And it actually works! Well at least it will tighten up a screw but you will need a reverse one to allow a screw to be backed out.

Interestingly, it seems that the tolerances allowed in the STL are too large for the form 1+ (I guess the resolution on the ISS printer aren’t as good as ours) causing the internal mechanism to have a bit too much movement.


STL file above

Thx for posting, I was just about to print this to see if it would work. Likely still will so I can show it around but before I do can you explain tolerance issue and if you think there is an obvious fix I might try? I assume the problem is either the gap between the round bottom of the gear or the gear itself with the body? Any issue with little level?

You are exactly right. The circular element inside has a bit much wiggle room. It took a bit of aggression to snap the mechanism and get it all to work. Occasionally the lever doesn’t doesn’t engage the gear but it’s a nice piece :smile:

I printed it with the back facing the build platform at an angle. Preform couldn’t really handle printing the internals without having bits floating

I printed it and it came out like a solid block. I printed using Grey #2 at .1mm, without supports (back against the build platform) . I did the latter because (1) it’s suppose to print without them and (2) in looking at it layer by layer I thought it would print without them. So I’m guessing the problem was the .1mm setting? Curious what your settings were.

I will upload my print file this evening.

I printed it with supports. I have learned the hard way that the Form 1 can be difficult at the best of times to create working single objects. Attempts at bearings etc have generally failed.

I don’t doubt that this print would work on a filament printer printed on the base but sadly it seems not on the form 1+

I had to get quite rough with the mechanism to free it up as well. Have you tried applying a lot of torque to the wrench square head?

Yes, I did try to break it loose, broke it off. It ain’t movin’ :slight_smile:

Ok tried uploading the form 1 file but it’s too big and the forum won’t let me upload a zip file. If you PM me your email address I’ll send it through.

Sorry to be late in responding, been out of town. If you can please email the file to


File is on it’s way

did the print work?

Sorry to bump up an old thread but I was trying to print this but came out as a brick as well. Please email me your print file to Thank you


I’ll have a dig and see if I can find it. Interestingly I printed it a second time and it came out solid (I broke the 1/2 inch piece off trying to free it up) so I may have just got lucky the first time.


Great, please advise when possible. I did scale mine down half size so that may have been my issue… but I want to have a .form piece that I know for sure works before proceeding.