Shopping List

What you need to buy

Before you get started on your SFX-100 journey, please be sure to read (if you haven’t already done so) the 1.4 Important Items to understand section.

A list of all parts required to build the SFX-100 Actuator.

Most of our team is located in Germany, so most of the links below point to German websites. Supplier and URL are to help you identify the right part. Some of the community on forums have put together their own lists/help.


Please check the exact spec of the part you’re purchasing from the supplier’s website – suppliers URL’s change, options on their sites change. Eg they may add a different option or spec for a part, and the URL points you to something different.

Item Details Quantity Supplier URL
aluminium profile Systemprofil K50 length: 250mm Teile Nr. H950N1010z 4 Kinetik
thread insert Teile Nr. H92RH10M8 32 Kinetik
slot nut K45/K50 (N10)-M8, einschwenkbar 16+ Kinetik
hollow shaft diameter = 30mm / length = 270mm / chamfer (both sides) 4 Smalltec
ball screw and nut type 1605 / length = 250mm 4 Modellbau-Letmathe
fixed bearing type FK12 4 Modellbau-Letmathe
linear bearing type LMEK30UU 4
shaft coupling type 30L40 / size 10,0 – 16,0mm 4 Dold
D-Sub cable 25 pol / plug-plug 4 Reichelt
D-Sub breakoutboard 4 Amazon
Arduino Leonardo 1 Amazon
cables Arduino wiring 1 Amazon
AC servo motor * type 90ST-M02430 220V 750W 4 Aliexpress
breadboard 1 Amazon
(OR) Wago Connectors
emergency stop 1 Amazon
O-ring 23,5 x 30,5 x 3,5mm 4 Amazon all four included in this set:
3d-printing filament type PLA 3 Amazon
floor protector rubber feet 4 Amazon

*Modbus RS-323/485 interface is an option. We do not support this at the moment, but if I would suggest to order this option for future proofness.

Type Size Quantity used for URL
DIN 912 M8 x 40 32 fixed / linear bearing mount
M6 x 85 16 motor mount * Note if you can’t find 85mm, 90mm will work.
M6 x 25 16 linear bearing
M4 x 25 16 fixed bearing
DIN 6912 M5 x 20 24 slider
DIN 125 A8,4 32 fixed / linear bearing mount
A6,4 32 linear bearing /motor mount

Patience is a virtue

You're dealing with typical B2B not B2C companies

In this day and age we have an expectation around buying things online. Confirmation emails within the hour, shipping out next day. Not so in engineering supply chain – often emails will take a few days turnaround, fulfilment might take week(s) with different global holidays impacting timelines.

Please have patience. For instance the Aluminium Extrusion, it wouldn’t be a companies core business to sell small pieces of extrusion to hobbyists and we are lucky that they do.

It’s a DIY project that this comes with the territory. Please allow 1-2 months to source and receive everything. You might be lucky and get everything done in a few weeks, plan on a month.

We suggest for the impatient types, buy your 3D printer straight away and start printing. It will take 2 weeks so that will keep you occupied for a little while.

110v vs 220v

The servo drives are 220v

Unfortunately there are no 110V servo drives (or selectable voltage) servo drives that suit our purposes. As such if you’re in a country with 110V you will need either a 220V outlet to be installed (OR) a step up voltage converter. You can research the forum threads listed on the homepage for other SFX builders and their experiences. Please note that it is highly unlikely you would see a full 3kW peak power consumption.

Example of voltage converter :

3D Printers and Software

Cheaper sometimes not better

You will likely find it’s cheaper to buy a 3D printer that outsource the printing of your parts – plus you’ll now have a 3D printer to label yourself a #maker and build a lot of other things. If you have any issues with sizes or need to reprint parts, or have friends that want to join the SFX100 club you’ll be glad you bought a printer.

Depending on your budget and printer you buy you may need to buy “Slicing” software, or you may choose free/bundled software to do this. For example a commercial product “Simplify3d” we provide known good settings, along with Prusa’s Sli3r PE Edition which is freely downloadable.

Please refer to Section 4.2 for more details about outsourcing, printers and printing.

Testing and checking

Check when items arrive

We suggest when your parts arrive check them. Make sure you receive the correct quantities, lengths and all parts are up to your acceptable standard. You’ll be really frustrated building actuator #4 to find you’ve run out of a critical piece!

Items to check :

  • You have grease nipples for your ball screws
  • Correct numbers and lengths of washers, bolts
  • Correct lengths of hollow shaft
  • Wire and bench test servo motors as you get them