MLAstro SAL-33 (Pre-Order) Batch 5
The Ultimate Harmonic Mount
$1099.00
Out of stock
MLAstro SAL-33
Not Just Another Harmonic Mount
The wait is finally over. After a year of design, testing, and refinement, the MLAstro SAL-33 is ready for preorder. This isn’t just another no-name, corner-cutting, Chinese-made mount where you’re left on your own after checkout. You can now have your mount personalized with a laser engraved logo artwork or text of your choice . See how to personalize your mount here. https://mlastro.com/mlastro-sal-33-personalized-laser-engraving
The SAL-33 was built by astronomers, for astronomers. We started by addressing the pain points that frustrate users the most — flimsy Alt-Az bases, telescopes drooping the moment power is cut, overheated anodizing fading in the Sun, and inferior Harmonic drive with huge PE...
Instead, we engineered a mount that cuts no corners: precision CNC machining, hand-selected harmonic drives, solar-ready coatings, and user-serviceable electronics. And we’ve priced it to stay accessible, without stripping away the quality you depend on.
The result? A mount that doesn’t just meet expectations — it redefines them.
*The final commercial mounts will feature some minor cosmetic updates compared to the production prototype shown here.
Innovative PA Design
Experience it once, and every other mount feels outdated.
Polar alignment has been neglected for too long. Many mounts simply slap on a sloppy Alt-Az base as an afterthought. The SAL-33 is different. We built the MLAstro Zero-Shift Alt-Az base using micron-level CNC machining to eliminate flex, creep, and play. Alignment becomes smooth, precise, and rock-solid — and once you’ve tried it, every other PA mechanism feels primitive.
Customized Harmonic Gearbox
Handpicked low-PE gearboxes for sub-arcsecond guided performance.
Not all harmonic drives are created equal. Budget mounts use cheap gearboxes with massive periodic error, masked by heavy guiding. That trick works for nighttime imaging — but for high-precision solar scanning with the MLAstro SHG 700, the huge periodic error of inferior harmonic gearboxes is brutally obvious, stretching and compressing scans due to the uneven slew speed.
So cutting corners was not an option for MLAstro. The SAL-33 uses only Customized low-PE 17:100 gearboxes, hand-selected to deliver tracking accuracy that rivals mounts twice the cost. Yes, it eats into our margin — but it means you get true sub-arcsecond guided performance that no shortcut can fake.
Micron-Level Precision CNC Machining
We use only the finest materials, paired with state-of-the-art CNC machining that meets — and often exceeds — industrial standards.
Astronomical equipment demands uncompromising precision. A mount requires even more. To make the Zero-Shift mechanism work flawlessly, without play or backlash, we machine certain parts to tolerances an order of magnitude tighter than the industry norm. That’s the level of detail needed, and that’s the level MLAstro delivers.
Behind every mount is one of the most experienced CNC operators and industrial designers in the field, ensuring rigorous quality control and minimal unit-to-unit variation.
Simply put: no other mount on the market matches the level of finish and precision that we achieve. Period.
Pointing Memory and Fail-Safe Brakes
FRAM memory and a physical RA brake keep your gear safe and convenient.
Ever had your setup sag helplessly when the power dies? With the SAL-33, that nightmare ends. A physical RA brake locks your payload in place, while back-EMF braking on DEC ensures safety across both axes.
Meanwhile, FRAM memory stores pointing data even after shutdown. Power cycle? Your mount wakes up exactly where it left off. For remote users, this means no re-homing, no annoying re-platesolving — just continuity.
Solar-Minded Design
Engineered for the Sun
Most mounts weren’t designed to sit under the midday Sun. Dark anodizing overheats, coatings fade, and electronics cook. The SAL-33 was built with solar imagers in mind. Its reflective silver finish shrugs off solar radiation, keeps the mount cooler to the touch, and never fades.
For the first time, you have a harmonic mount designed not only for deep-sky nights but also for spectroheliography and solar imaging during the day.
MLAstro-Level Customer Service
You'll never find a comparable service elsewhere
When you buy an SAL-33, you get more than hardware — you get us. Direct, responsive support from the same team that designed and built your mount.
And unlike sealed-box mounts, the SAL-33 is user-serviceable. Burn out a stepper driver? Swap in an off-the-shelf replacement. Motor failure? Unbolt and replace in minutes. For the rare issues you can’t solve yourself, we have forwarding warehouses in the US, UK, EU, and Australia, so you only ever ship locally for service.
Try getting that from a sub-$2000 Chinese mount.
Official OnStepX Hardware
The only Official OnStepX harmonic mount in production.
The SAL-33 isn’t locked down—it runs on OnStepX firmware, giving you full access to open-source flexibility and fine-tuning. Need more motor current for a heavy payload? Just adjust the driver settings on the fly. Fighting a slight RA drift? Tweak the track rate and you’re set.
For those who like to dig deeper, we’ve gone further: our firmware and pinmap are public on GitHub, so you can customize, experiment, and future-proof your system.
As an official OnStepX supporting partner, MLAstro gives back directly to the project. We recognize the incredible work that’s gone into OnStepX and are proud to be part of it. Partnership also means we maintain a direct line with the OnStepX team for bug reports, feature requests, and ongoing collaboration—ensuring our hardware and OnStepX firmware deliver unmatched compatibility.
Robotic PA ready
MLAstro is working on a robotic polar alignment kit. Robotic PA has been part of the plan since the SAL-33 was conceived. That is why we designed the PA to work without tightening any locking knobs, and why the adjustment knobs are light enough to be driven by a small thumb sized motor with a gearbox.
Now that ZeroShift Alt Az base is done, the remaining work is motorizing it and finalizing platform compatibility. We are already working with INDI to map a path forward so Robotic PA can integrate with KStars EKOS 3 point polar alignment. NINA support is also possible since a Robotic PA protocol exists. The kit will also support manual control via a standalone web interface built into the system.
The SAL-33 was designed for this from day one. The mount head can be detached from the Alt Az base and moved onto the Robotic PA kit by removing a few screws. Target availability is late 2026 (Highly speculative at this point). It will be retrofittable to all existing SAL-33 mounts.
Category | Specification |
|---|---|
Mount Type | Harmonic drive equatorial/alt-az dual-mode |
Load Capacity | Visual: Up to 15 kg without CW, Up to 20 kg with 5 kg CW |
Slew Speed | MAX 4°/s |
Drive System | High-quality low-PE 17:100 harmonic drives for both RA and DEC |
Brakes | Physical brake on RA, back-EMF engine brake on DEC |
Retains Pointing | Yes, pointing retained after power cycle |
Firmware | Official OnStepX hardware with full support |
Open Source | Firmware and pinmap fully open-source |
Build | Precision CNC-machined metal |
Alt-Az Base | MLAstro Zero-Shift Alt-Az design |
Connectivity | USB Type-B, WiFi (AP and Hotspot modes), Bluetooth |
Mount Head Weight | 5.3 kg |
In the Box | Mount head only (PSU not included) |
Operating Temperature | -20 to 50C ambient temperature |
Recommended PSU | 12V 3A minimum, 12V 5A recommended. 5.5x2.1mm center positive |
Warranty | 1-year limited warranty |
Q: The current order shows Batch 5—what happened to Batch 4?
A: Batch 4 sold out in 31 Jan 2026. All orders placed after 31 Jan 2026 are now placed in Batch 5.
Q: When will the 5th Batch ship, and how long will delivery take?
A: We plan to ship the 5th production batch mid-late June 2026. That said, this is a startup-scale project, and delays can happen as we transition from prototypes to full production. I’ve already built in buffer time, but if unforeseen issues extend the timeline, I’ll keep all customers updated with progress reports and notify you of any delays. I take deadlines seriously, and my track record shows I usually meet or even beat them. Shipping time is typically 2–3 weeks worldwide.
Q: Can I cancel my order and get a refund?
A: Yes. As long as your order hasn’t shipped, you’re entitled to a full refund, no questions asked. Just email me at trong.minh@mlastro.com, and I’ll process it immediately. If your order is shipped with tracking number, the sale is finalized and we do not offer refund/return option unless the mount was defective beyond customer service ability under our guidance. Then we'd take back the mount via our forwarding warehouse and the user will be presented with a refund option or repair and send back at MLAstro's discretion.
Q: What tripod connections does the SAL-33 use?
A: The SAL-33 uses a 3/8" thread plus 3 × M6 holes — the same as the ZWO AM5. Any tripod that works with the AM5 will work with the SAL-33. For best results, we highly recommend the MLAstro P-200 Pier Extension, which prevents your camera from colliding with the tripod and adapts common tripods like iOptron 1.75"/2" and SkyWatcher EQ3/EQ5/EQ6 tripods and ZWO TC40. We can even do a customized adapter for your tripod, just put an order comment when you place your order and we'll get back to you with the details.
Q: Why is this so cheap? A comparable mount would easily cost twice as much. Did you make it so cheap using cheap materials/parts?
A: I can promise you the SAL-33 isn’t cheap because of cheap parts. It’s built from top-tier materials, tight tolerances, and proper machining. The price is low because of a few very practical reasons:
Vietnam factor: Labor here is dirt cheap compared to the West (even compared to China). A skilled CNC operator makes under $30/day. A family of four lives fine on $50/day. So yeah, I’ve got a highly skilled workforce at a fraction of the cost. And no, it’s not “new slavery,”it’s just local economics, thanks for asking.
Batch production, prepaid: I only build in batches, and they’re all prepaid. That means no stock, no loans, no risk of me losing my house if this mount doesn’t sell. Less financial risk = I can afford to run thinner margins.
Razor-thin margins: MLAstro is still new. I’ve got other ventures bankrolling me, so I don’t need this to make me filthy rich right now ( I wouldn’t complain if it did, LOL). But the mount market is crowded with big names, and if I want to make some noise, I’ve got to keep the price stupidly attractive. Once we’ve proven ourselves, expect the price to creep up—still competitive, just not “too good to be true” cheap like now.
This started as a hobby that turned into my dream job. Of course money matters—this is still a business—but I’ll never make it the first priority. I enjoy the work, and I enjoy talking shop with people like you. That’s the real payoff.
Q: How does the warranty and servicing work?
A: The SAL-33 includes a 1-year limited warranty covering manufacturing faults. The mount is designed to be user-serviceable — if an electronic fails, it can be swapped easily with off-the-shelf parts. For repairs beyond user scope, we maintain forwarding warehouses in the US, UK, EU, and Australia, so you only need to ship domestically for service.
Q: Why is the recommended imaging capacity lower than the visual capacity?
A: For visual use, the SAL-33 supports 15 kg without counterweight, or 20 kg with 5 kg CW. For imaging, we recommend ~70% of that (~10.5–14 kg).
Some manufacturers downplay this rule, but it applies to all harmonic mounts. Torque ratings only tell you how much the motors can move, not how well they can track. Near the load limit, steppers are prone to vibration, resonance, and missed steps — all of which degrade guiding.
That’s why we set conservative imaging limits: to guarantee smooth tracking. You can push beyond our recommendation, and it may still work “good enough,” but we only guarantee performance within the stated range.
Q: I’m having trouble using the SAL-33. How do I get help?
A: Start with our Quick Start Guide. If that doesn’t solve it, join our user group where our support team is active. For one-on-one help, email me directly, and I can arrange a video call with remote desktop support.
Q: Why is shipping to the US more expensive?
A: The US recently imposed a 20% blanket tariff on shipments from Vietnam. To avoid this, we use a specialized courier that guarantees tax-free delivery but charges a 5–7% service fee. This is why US shipping is about $190 vs. ~$140 for other regions. The upside: your package arrives at your door without extra paperwork, hidden charges, or surprise taxes, all tariff/tax is included.
Q: Can you reduce import or VAT tax for my order?
A: In most cases, yes. For the SAL-33, I’ve added a “Tax Free” shipping option (with a small surcharge) for countries outside the US—so you’ll have two choices there. For US orders, however, “Tariff Included” is the only available shipping option. For more informations how the "tax free" option are handled, see this.
Q: Is there an iPolar or PoleMaster adapter?
A: Yes. We have a working 3D-printed adapter model. Email me, and I’ll send you the STL file so you can print it locally.
Q: Do you provide a counterweight for this mount?
A: Shipping heavy counterweights isn’t cost-effective, so we don’t have them. The counterweight bar (20 mm diameter) is optional, and you can use any counterweight with a 20 mm bore.
Q: Does the SAL-33 have cable passthrough, a 12V port, or a USB hub on the saddle?
A: No. Adding integrated passthroughs and hubs would drive up both mechanical and electronic complexity — and cost — beyond our target. At this price point, we focused on core performance.
The good news: with harmonic mounts, precise balance isn’t critical. That means you can mount a small power box or USB hub where it suits your rig and still maintain clean, reliable cable management without compromising performance.
Q: Is there a manual?
A: Please see our Quick Start Guide
Q: How do I update the mount firmware?
A: Please see our instructional video here
The Firmware Installer is here https://test.mlastro.com
Q: How do I setup the mount to work with ASIAir?
Q: How do I setup guiding with PHD2 for optimal performance?
Q: How do I configure the SAL-33?
Drivers:
CP210x Drivers for Windows and MacOSX: https://www.silabs.com/software-and-tools/usb-to-uart-bridge-vcp-drivers?tab=downloads
ASCOM OnStepX Driver (You need ASCOM Platform 6.5 and above to use this): http://www.stellarjourney.com/assets/downloads/OnStep-Setup-1.0.43.zip
Softwares:
Sky Planetarium: OnStepX authorized planetarium software by Howard Dutton, OnStepX author. It has a lot of tuning, settings that other software lacks including mount modeling. This is a freeware with paid to remove the time limit. If you want cheaper license on this (retail for 30$ but we have those for on discount), please contact me via email. http://www.stellarjourney.com/assets/downloads/sky4.84.zip
PHD2 Guiding https://openphdguiding.org/downloads
https://drive.google.com/drive/folders/1c7LwPv9aFupNWOR6Qljlm04vXt8ptrKA?usp=sharing
Please download the adapter STL for those devices here