fully printable with no supports! The use of 1x wood screw is the exception here (to be used for its sharp point) and allows the tool to function as well as its metal counterparts.
Sturdy enough for workshop use, holding its position reliably & is easily adjusted.
could accept a carpenters mechanical pencil, but also any regular pencil too!
Other similar printed tools comprise of flat profiles which wobble & bend far too easily, they also have excessive play leading to inaccuracy. This model has increased strength, achieved with a monocoque-style leg design that houses all of the working components, and is an uprated ‘beefier’ version than my previous adjustable calliper design due to the conditions it will be under.
Holds any regular pencil (up to 7.5mm in diameter) OR commonly available 2.8mm lead ‘carpenters’ mechanical pencils (which are 13mm diam. in the main body and 5.7mm on the metal finger-grip portion)…..but regardless of brand, they are all pretty much the same shape. The specific ones I have can be found here.
The straight legs are 150mm long (from the pivot centre), and open up to a maximum of 200mm wide…. all meaning it can draw circles up to 400mm (16") in diameter! I am really pleased at just how well this assembles & performs.
Wood screw recommendation:
Metric 4.0 x 30mm (anything up to 40mm long could work, but just wont need to be screwed in as far)
Imperial #6 x 1-5/8" drywall (Thanks to ChopperOriginals for his recommendation in the comments on this)
I hope you like it!
If you do you may want to check out some of my other DatumCAD designs :)
Assembly:
Insert the 3x Adjuster nuts into the Legs: These snap fit and are deliberately tight to avoid coming out easily (so may require a decent amount of force before they click into place) try pressing or even tapping into place with a flat head screwdriver/punch if needed. Don't worry, they are all the same and can be inserted any way round!
Connect the Legs together: Just align the top hole of the legs, then push the Pivot pin through the hole in both legs (from whichever side you prefer) and secure in place using the circlip.
Insert Slider & Slider Bolts: Place the hole end of the Slider plate onto the same leg which will house the pencil, fixing in place using the shortest of the threaded bolts. Then insert the longer threaded bolt though the slot in the slider plate & into the other leg.
Insert Pencil Locking Bolt: The remaining bolt should be threaded with a short & plain end. Use this in the pencil fixing nut location.
Insert Wood-Screw: The hole is just fractionally smaller than the threads so the screw should thread its way in easily if you use a screwdriver.
Enjoy! Your adjustable bow compass is now ready to use - Simply insert a pencil of your choosing! :)
I love designing for 3D printing, please take a look at all my other models which are all free (and will always continue to be)… if you value any of the downloads enough & are able to support me, then please consider buying me a coffee to keep me going! www.buymeacoffee.com/DatumCAD
the great models keep coming!! 🔥
very neat little helper that is easy to print with the provided AMS profile. it’s of course a bit chunky but it works flawlessly so far.
quality CADing! thanks for sharing ❤️
Flattered that you think so and I do love seeing the printed results of other users like this.... that gold is particularly premium looking :) Thanks for you kind comments and for the Boosts too!!
Thanks for the feedback, it’s appreciated. I did worry the tolerance may be a bit too tight (and a would be a little dependant on filament etc.) but was just about perfect in my tests. That said, I will look to back it off just a touch more I think. Glad you like them and got it to fit though, they look smart in the blk/org combo 👍
Not much to say but GREAT PRINT AS ALWAYS! from DatumCAD. I would like to point out for those of us here in the states. 1-5/8" drywall screw works perfect! I had a ton of hardware but no metric wood screws and all the others were either too long or too short. Thanks again DatumCAD!
Very kind! and cheers for sharing your findings with the correct size of imperial wood screw. I am familiar when it comes to bolts & threads, but not these so didn’t feel I could specify in the model info. I will add this now so many thanks!! and for sharing your makes 👌
Been looking for something like this for my workshop. Very nice! Had to reprint one of the screws though, it broke so I upped the walls and infill. Printed in PLA matte (charcoal & red).
Thanks for this review, great to see the first one of these printed by someone other than me! Looks great in those colours too. Yes I tried to dial the tolerances down on this version as much as possible and should perhaps have noted it’s best to run the bolts through the nuts a few times before assembly, so may have been part of your issues. I will look to add this to the instructions. Thanks again for sharing!! 😀