¶ Preparation
Blind Joints
Threaded inserts
The aluminium extrusions that are tapped or have holes drilled into them are named (e.g. EX-A or EX-B) in all the assembly stages according to labels mentioned in the Blind Joints section above. The extrusions without holes or taps are not named.
¶ Assembly
OAM Assembly Part 1: Base
OAM Assembly Part 2: ALTAZ base
OAM Assembly Part 3: Top Assembly
OAM Assembly Part 4: Gearboxes
OAM Assembly Part 5: Final Assembly (unfinished)
¶ Screw torque
Different screws on OAM need to be fastened with different strength. Since almost no one has a proper torque wrench laying around, the assembly guide will reference 5 different tightening settings. Please follow them carefully to avoid damage to parts and ensure optimal rigidity.
1: Almost loose. Use the short side of your hex key and tighten it just past the screw biting.
2: Lightly tight. Use the short side of your hex key and tighten it with light force.
3: Use the short side of your hex key and give it a good twist. Do not use the long side.
4: Use the long side of your hex key and tighten it, but dont give it everything you got.
5: Use the long side of your hex key and tighten it as good as you can without stripping out the screwhead.
¶ OpenAstroMount Assembly Part 1: Base
In this step:
Parts:
- Base_Connector 1.1 & 2.2
Hardware:
- M4x12mm (15)
- M4 T-Nuts (15)
Instructions:
Attach M4x12 and T-Nuts in all shown locations of both parts. At the bottom of the parts, 3 locations are intentionally left free.
You can always right click an image and open it in a new window for a higher resolution version.
Parts:
- Base_Connector 1.1 with M4's attached
Hardware:
Instructions:
Screw the M5/M6x20 flathead screw into the end of the 100mm extrusion. You need to leave it sticking out about 2-3mm.
If using M6 flatheads, use one of the 6x12x1.0 shims under the M6 bolt. This should be done for all blind joints and is not called out in the rest of the assembly.
Attach the Base_connector_1.1 part with the single M4 screw (green) to the 2040 extrusion with torque 3. Position doesn't matter, this is only temporary.
Instructions:
Slide the 100mm extrusion onto the part. This might be a bit fiddly if the T-Nuts aren't aligned. Do not tighten any screws yet!
Instructions:
Slide the 200mm extrusion in with the longer side from the hole first (if using blindjoints). The head of the flathead screw needs to go into the slot of the extrusion (if using blindjoints). Push it in until it makes contact with the 2040.
The head of the flathead screw should be visible through the borehole in the extrusion (if using blindjoints).
Instructions:
The order in which you tighten the screws is important now.
Start by pushing the 200mm extrusion gently down so it makes good contact with the part aswell as the 2040 extrusion.
First lightly tighten the 2 yellow screws on the 200mm extrusion.
If using blindjoints, lightly tighten the M5/M6 bolt to torque 2 now. It should still be able to rotate slightly.
Now tighten all yellow screws to torque 3.
Then loosen the red screw and remove the 2040 extrusion. It has only been used for alignment.
Now tighten the 3 green screws to torque 4. The middle one of them can only be accessed through a small hole in the part.
Fully tighten all M4 screws to torque 4.
Then fully tighten the M5/M6 bolt to torque 5.
Parts:
- Base_Connector 2.2 with M4's attached from previous step
Hardware:
- 2020: 200mm
- M4x12 screws (6)
- M4 T-nuts (6)
Instructions:
As before, first attach the part to a 2040 extrusion with the green screw. Position doesnt matter, this is only temporary.
Then slide on the 2020x200mm extrusion.
Instructions:
While pushing the extrusion down into the part and 2040 extrusion, tighten the screws in the following order:
Tighten the yellow screws to torque 4.
Loosen the red screw and remove the 2040 extrusion.
Tighten the green screws to torque 4. The left one can only be accessed by a small hole in the part.
Instructions:
Now attach the missing 6 M4x12 and T-Nuts. Lay the parts aside.
Instructions:
Repeat the steps for the other two base_connector parts. Take care to not mix these two up with the ones you've already assembled.
Once you have assembled the second pair of base_connectors, lay them aside. You will not need them for a while.
Parts:
- 30mm_pole_holder_1
- 30mm_pole_holder_2
Hardware:
- 2020: 2x100mm
- M4x12 screws (4)
- M4 T-nuts (4)
Instructions:
Take the pole_holder parts and attach M4x12 and T-Nuts to them. Attach them to the 100mm extrusions as centered as possible. Note that the holders a tiny bit shorter than the extrusions.
Assemble them on a flat surface to ensure everything is straight.
Instructions:
Attach the 100mm extrusions with the pole_holders to the parts you assembled before. Make sure theyre inserted all the way and tighten them with the two red marked M4 screws.
Parts:
- 51115_bearing_holder
Hardware:
- 2040: 300mm
- M4x12 screws (4)
- M4 T-nuts (4)
Instructions:
Attach 4 M4x12 and T-Nuts to the 51115_bearing_holder. This part should also have 2 M3 inserts inserted on either side.
You need to attach the part to the middle of the 2040 extrusion. To help you, the part has markers on both sides indicating its middle. The distance from the marker to the end of the extrusion should be 150mm. If possible, use digital calipers for this to get it as precise as possible.
Once you have aligned the part, tighten it's screws to torque 3.
Hardware:
- Two extrusions of any length
Instructions:
Get two extrusions (which ones exactly doesn't matter) and lay the 51115_holder with the extrusion on its head. The two extrusions are only used temporarily to avoid damaging the thin parts of the 51115 holder.
Instructions:
Put the base_connector with the two extrusions on the 2040 extrusion as shown. This is the base_connector you assembled first (base_connector_1.1). It might be a little fiddly, as all 4 T-Nuts will have to be aligned with the slots.
Move it so that the round part of the 51115_holder and pole_holder are aligned (marked red).
Parts:
- 30mm_bracket
Hardware:
- 2020: 100mm (EX-G)
- M4 inserts (2)
- M4x12 screws (8)
- M4 T-Nuts (8)
Instructions:
Attach 4 M4x12 and T-Nuts to the 30mm_bracket as shown. Then insert the tapped 100mm extrusion. Lightly tighten all four screws first before fully tighten them to ensure proper alignment.
The part is a tiny bit shorter than the extrusion. Make sure it is centered well.
The part should also have two M4 inserts inserted on both sides.
Instructions:
Attach remaining 4 M4x12 and T-Nuts as shown.
Hardware:
- 2020: 100mm
Instructions:
Take any 100 extrusion and attach it on the left side of the part. Position doesnt particularly matter, it is only used temporarily for alignment, but attach it roughly in the middle.
Instructions:
Take the base_connector_2.2 from the beginning and attach the 30mm_bracket with the alignment extrusion touching its end. Fasten the screw.
Remove the 100mm extrusion that was used for alignment!
Instructions:
Attach the part as shown and tighten the 5 red marked screws to torque 4. Push the two base_connectors together while tightening the screws.
Hardware:
- 30x300mm shaft
Instructions:
Take your 30mm shaft and insert it as shown to test if everything fits. It's OK if this is a bit difficult, it needs to sit tight.
If it sits very loose in the 51115_bearing_holder part, use some tape to make it fit tighter.
If the 30mm_pole_holders dont make proper contact, go back a few steps and adjust their position.
Instructions:
Take a extra 100mm extrusion and attach it as shown. This is again just used for alignment.
Instructions:
Attach the base_connector_2.1 as shown and tighten the 2 red marked screws to torque 3. Make sure the 200mm extrusion makes contact with the alignment extrusion, you may have to force it a little.
Remove the alignment extrusion.
Hardware:
- 2040: 300mm
Instructions:
Slide the 2040 on as shown. Use a additional 2020 extrusion to align it with the other 2040 extrusion.
Tighten the 1 red marked screw on it just enough so that the 2040 cannot move.
Instructions:
Flip the assembly around. Tighten the 2 red screws to torque 3. Make sure the T-Nuts properly grab on the extrusion. You can looks through the slot from the side to check their position. This should pull the extrusion to the 51115_holder part.
After that, fully tighten the 4 M4 screws from the previous step to torque 4.
Instructions:
Take the remaining base_connector_1.2. Remove the red marked T-Nut, but leave the M4 screw in it's hole. The adjacent screw should prevent it from falling out.
Instructions:
Insert the T-Nut into the slot as shown. Align it with the slot of the 2040 below.
Instructions:
This step is a bit fiddly, not gonna lie.
Insert the part from a slight angle, while ensuring all T-Nuts are aligned with the slots.
Instructions:
Tighten the 2 red screws to torque 3 first while pushing the two base_connectors together. Then tighten the 4 green screws to torque 4.
Parts:
- RA_Ring_3
- RA_Ring_2
Hardware:
- M4x12 screws (8)
- M4 T-Nuts (8)
Instructions:
Insert the screws and T-Nuts as shown in both pieces. Insert both between the extrusions and tighten.
Parts:
- RA_Ring_1_split_1
- RA_Ring_1_split_2
Hardware:
- M4x12 screws (4)
- M4 T-Nuts (4)
- M3 inserts (6)
- M3x10 screws (2)
Instructions:
Insert M4 screws and T-Nuts into grooved side. Insert M3 insert into larger holes on each middle side (that gets joined).
Insert M3 inserts into the two hole pairs at the ends of the pieces.
Connect the two pieces with the M3 screws, but do not tighten at all.
Repeat this assembly with the other side pieces.
Hardware:
- M3x10 screws (8)
Instructions:
Attach the two assembled RA split ring pieces to the 2040 extrusions of the base assembly.
First fasten the two pairs of M3x10 screws at the edge.
Then fasten the outermost two M4s.
Then tighten the M3s that join the side pieces.
Then tighten the inner M4s.
Hardware:
- 300mm x 30mm shaft
- M4x12 screws (2)
Instructions:
Insert shaft through holder, into top part (30mm_bracket). Make sure the shaft goes all the way in and then secure with two M4x12 screws.
Congratulations, you have finished the base of your OAM!
Continue with Part 2 of the instructions:
OAM Assembly Part 1: Base
OAM Assembly Part 2: ALTAZ base
OAM Assembly Part 3: Top Assembly
OAM Assembly Part 4: Gearboxes
OAM Assembly Part 5: Final Assembly