Modular Motorised Rowboat

It works! Well mostly. 

Manual_01

2023_10_10-1

Modular Rowboat

Intro:

So yawanna build a rowboat! Here’s a module that can be dropped into most any model boat or you can build multiples and put them into the hull modules I've designed.

In addition to the printed parts you will need the following hardware:

Gobs of M3 socket head cap screws

A good supply of M3 Nyloc nuts (or use Loctite and normal nuts)

Gobs of M3 x 5mm long heat set inserts

1: shaft coupling: 2mm to 5mm

 4mm id x 8mm od bearings or bushings

 5mm id x 8mm od bearings

2: worm drive units with worm wheel. I get mine here: https://www.aliexpress.us/item/3256801118777018.html?spm=a2g0o.productlist.main.1.456dac48r5GsH5&algo_pvid=0e153a95-c55e-44ef-86c0-e15a9f7d9492&algo_exp_id=0e153a95-c55e-44ef-86c0-e15a9f7d9492-0&pdp_npi=3%40dis%21USD%210.89%210.61%21%21%21%21%21%40212248ba16838534900482402d0756%2112000015642806065%21sea%21US%212394886246&curPageLogUid=C73npfBZLVzS

1: 4mm dia x 50cm length of steel or brass rod

2: 5mm dia x 50mm length of steel or brass rod plus another for each additional rower you want to add. 

A bunch of 4mm and 5mm i.d. shaft collars

1: DC electric motor, approx 28mm dia.  Amazon: AUTOTOOLHOME 6-12V Mini DC Motor High Torque Gear for Traxxas R/C and Power Wheels PCB DIY Electric Drill: Amazon.com

 Tools you’ll need:

Lathe; a small one is fine.

4mm drill bit

M3 tap

Hacksaw and a file to deburr shafting

Heat set tool:  a soldering iron

Small set of metric hex  keys

2: 9mm open end wrenches

7mm open end wrench or print the design in the files

5.5mm socket wrench

Deburring tool

Arbor Press or small hammer to dismember the worm wheel from its shaft

Rout-a-burr hand tool 

Assembly Instructions:

1. While the parts are printing remove the axle from the worm wheel. Note: there’s a steel pin molded into the gear so you’ll have to use considerable force to push the axle free. Push from the thin end of the axle. An arbor press will make quick work of it.

2. Deburr where the axle and pin tore out of the molded gear

3. After rounding off the sharp edges, press in the 60 mm length of 5mm dia rod into the nylon gear, making sure it’s centered well

4. Chuck the metal worm in a lathe with the hole end exposed; use brass or aluminum packing to avoid damaging the o.d.  

5. Drill the worm gear clear through with the 4mm dia drill bit, removing the spud on the other end.

6. Remove the worm from the lathe and clean up the end of the newly created through-hole

7. Attach the motor to the 4mm shaft with the shaft coupling 

8. Slide the worm onto the shaft with the slotted end away from the motor

9. Slide the worm drive adapter onto the shaft, engage it with the worm and tighten down the set screws

10. If the parts are all printed go ahead and insert the M3 x 5mm heat set fasteners where they belong with the soldering iron. Make sure all of the heat set fasteners that go into mating surfaces sit flush and sand these intersections smooth, removing any excess plastic.

11. Next tap the 4: M3 holes in the top of the main body of the gear box  

12. Press the 4mm id x 8mm od bearing or bushing into the hole at the back of the gearbox.

13. Slide the motor-worm-shaft assembly into the gearbox so the shaft sticks through the  bearing 

14. Clamp the motor in place; if it's a loose fit put some two sided sticky tape on top of the motor under the clamp.

15. Tap the M3 holes in the rowing frame

16. Attach the oarlock support brackets to the support frame with 4: M3 x 8mm SHCS

17. Attach oarlocks to the support brackets with M3 x 18mm SHCS

18. Thread M3 Nylocs onto the ends of these bolts but don’t snug them down: leave them a little loose so the oarlocks can swivel.

19. Slide the 5mm id x 8mm od bearings onto each end of the 5mm dia x 60mm rod that's in the middle of the worm wheel

20. Slide the 11mm spacers on next

21. Press a crank disk onto either end of the 60mm shaft, making sure their ends are flush with the ends of the rod. Use the 9mm wrenches to make sure the oar holes line up. 

22. Insert the handle of each oar into the hole in each crank disk, then lay the oar in the oarlock and fasten it in place with the M3 x 12mm bolt, making sure that the oar is free to flop about.

23. Bolt together as many hull sections as you want; making sure to insert TPU filament in the U shaped channel between each pair of bulkheads.

24. Bolt together another worm drive assembly at the aft most rowing position

25. Slide a keeper over the oars at the forward and aft most locations

26. Attach the crank bar's slotted hole to the aft most rowing station's oar, then slide the oarlock assembly inboard until the oar handle pokes through the crank disk

27. Attach the round hole end of the crank bar into the forward oar assembly in the same way. Cut the crank bar if the whole length is not needed, making sure that the slotted aft hole remains. The round hole end then goes towards the bow.

28. Slide the other oars into their mating holes on the crank bar and tighten the oarlock mounts to the rowing frame

29. The final step is to ‘clock’ the two worm gear assemblies to work in unison. Once that's done tighten down the worm drive dogs and fasten the worm in place with shaft collars fore and aft

30. Wire up the motor, add a battery, radio or whatever you want, then attach the deck to the bow with three: M3 x 10mm flat head screws.  

PS remember I'm broke and Patrons get access  to .stp files and other perks! 

 https://www.patreon.com/Steamboat_Ed