Re: DIY spring loaded worms in 5 minutes
On Wed, Sep 23, 2020 at 09:29 AM, Henk Aling wrote:
As an aside, here's my OnStep controller to the right.? It's a Wemos R32 with a CNC v3 shield.? The Raspberry Pi 2B running Kstars and Ekos (client and server) is to the left.? I run it with 0.9 degree steppers with TMC2130 controllers with SPI for slewing at full step, microstepping 16x for tracking.? I start out using my Android cell phone as a remote over Bluetooth for alignment, then continue with Ekos and Kstars for tracking, guiding, plate solving, etcetera, remotely logged from my Galaxy Tab A with VNC.
Nice, I also have the??Wemos R32 with a CNC v3 shield for an OnStep using the original hurst stepper motor. I just have a GM8 RA base so it serves as a heavy duty star tracker and solar scope mount. The whole OnStep was also a 5 minute mod :)?
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Re: Losmandy GM8 OnStep upgrade
Sure, leave me an email on dominik.ggorski at gmail.com :)
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Re: Losmandy OPW Assembly
Hi Sebastian,?
That looks right to me for a standard Losmandy genII spring loaded OPW for a GM8 mount. It should work for both RA and DEC on GM8. How did you buy it, direct from Losmandy or private party??
--
Chip Louie Chief Daydreamer Imagination Hardware?
? ?Astropheric Weather Forecast - South Pasadena, CA?
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Re: DIY spring loaded worms in 5 minutes
That's out of the box thinking. I don't feel as bad using neoprene washers now ;0
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Re: Losmandy GM8 OnStep upgrade
Dominik, I could help you with belleville washes. Let me know, if you want some.
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Re: Losmandy OPW Assembly
Below are the pictures of the OPWB I received. Nothing else. I assume, there are two kinds of OPWB available now - the one I received and spring loaded OPWB. They both have the some cover.
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My small solution to the missing alignment scope bung, I printed a solid bolt and another with a hole in the centre for the 3mm led I have on order. In Luminous green in case it is dropped in the dark.
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Re: DIY spring loaded worms in 5 minutes
HI Henk
Wow that is some McGyvering there, nice work!
i hope you will let us know about the results
>>>I'll duck for cover now.? I've been on this board long enough to know what's coming, so fire away...
I don't see any references to vixen plates, so I think you're safe on that one for now :)
Brian
On Wed, Sep 23, 2020 at 9:29 AM Henk Aling < haling@...> wrote: This morning while the coffee was brewing I fashioned my own spring loaded worms.? The materials:
- Rubber bands cut from an old road bicycle inner tube.? This kind of rubber is very resilient, do not use household rubber bands.
- A strip of sheet metal about 1 cm wide and 5 cm long, just guessing, cut with tin snips.
Installation steps:
- Loosen the outer worm block by loosening two screws:
- The screw at the bottom of the frame that the block is mounted on, just slightly so there is little vertical play.
- The screw on the housing, this can be loosened a bit more.
- Wrap the rubber band twice around the screws at the bottom.? This should provide quite a bit of tangential force that pushes the outer worm block towards the motor side.
- Fashion the sheet metal to wrap around the rear edge of the housing and around to provide slight pressure on the housing screw.? This screw is directly screwed into the worm block so it provides slight lateral pressure inward that keeps the worm engaged without slack.? You can vary the pressure by positioning the screw, or simply bend it a bit more or less.? Not much pressure is required.
- I should note that I don't use the Oldham couplers but flexible aluminum shaft couplings for stepper motors.? These couplers also provide some pressure but I think this should work with the Oldham couplers just as well.
I did this for both RA and DEC and slewed both around at full speed with my OnStep controller.? It seems to work fine, frankly.??I can't wait to try it out under the stars once the fog stops rolling in.? Here are some pictures:
The first 4 pictures are of the DEC worm block:
I only have one picture of RA, all you can see the rubber band and a glimpse of the sheet metal spring.? The other RA pictures were blurry.
As an aside, here's my OnStep controller to the right.? It's a Wemos R32 with a CNC v3 shield.? The Raspberry Pi 2B running Kstars and Ekos (client and server) is to the left.? I run it with 0.9 degree steppers with TMC2130 controllers with SPI for slewing at full step, microstepping 16x for tracking.? I start out using my Android cell phone as a remote over Bluetooth for alignment, then continue with Ekos and Kstars for tracking, guiding, plate solving, etcetera, remotely logged from my Galaxy Tab A with VNC.
I'll duck for cover now.? I've been on this board long enough to know what's coming, so fire away...
-- Brian?
Brian Valente portfolio
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DIY spring loaded worms in 5 minutes
This morning while the coffee was brewing I fashioned my own spring loaded worms.? The materials:
- Rubber bands cut from an old road bicycle inner tube.? This kind of rubber is very resilient, do not use household rubber bands.
- A strip of sheet metal about 1 cm wide and 5 cm long, just guessing, cut with tin snips.
Installation steps:
- Loosen the outer worm block by loosening two screws:
- The screw at the bottom of the frame that the block is mounted on, just slightly so there is little vertical play.
- The screw on the housing, this can be loosened a bit more.
- Wrap the rubber band twice around the screws at the bottom.? This should provide quite a bit of tangential force that pushes the outer worm block towards the motor side.
- Fashion the sheet metal to wrap around the rear edge of the housing and around to provide slight pressure on the housing screw.? This screw is directly screwed into the worm block so it provides slight lateral pressure inward that keeps the worm engaged without slack.? You can vary the pressure by positioning the screw, or simply bend it a bit more or less.? Not much pressure is required.
- I should note that I don't use the Oldham couplers but flexible aluminum shaft couplings for stepper motors.? These couplers also provide some pressure but I think this should work with the Oldham couplers just as well.
I did this for both RA and DEC and slewed both around at full speed with my OnStep controller.? It seems to work fine, frankly.??I can't wait to try it out under the stars once the fog stops rolling in.? Here are some pictures: The first 4 pictures are of the DEC worm block: I only have one picture of RA, all you can see the rubber band and a glimpse of the sheet metal spring.? The other RA pictures were blurry. As an aside, here's my OnStep controller to the right.? It's a Wemos R32 with a CNC v3 shield.? The Raspberry Pi 2B running Kstars and Ekos (client and server) is to the left.? I run it with 0.9 degree steppers with TMC2130 controllers with SPI for slewing at full step, microstepping 16x for tracking.? I start out using my Android cell phone as a remote over Bluetooth for alignment, then continue with Ekos and Kstars for tracking, guiding, plate solving, etcetera, remotely logged from my Galaxy Tab A with VNC. I'll duck for cover now.? I've been on this board long enough to know what's coming, so fire away...
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Re: Losmandy OPW Assembly
Hi Sebastian,
This is a new genII OPW. The hole is where a cap screw goes with some mounting hardware and a spring to preload worm against the worm gear. To use thew newer genII OPWs you need a drilled and tapped hole in the plate that the OPW is attached to. You will need some hardware to do this, what other bits came with the new OPW? Please show photos of the other hardware.?
--
Chip Louie Chief Daydreamer Imagination Hardware?
? ?Astropheric Weather Forecast - South Pasadena, CA?
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Re: Losmandy OPW Assembly
Hi,
I have just received a OPWB. What is this hole in lower right corner for?
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Re: Losmandy GM8 OnStep upgrade
So I installed new stepper motors yesterday and cleaned things up a little. There were NEMA23 stepper motors, but due to their extremely high inductance they worked liek disaster. I printed NEMA17 adaptors and used new motors I always use with OnStep's.
All the things are very silent now and works smoothly, there are no bearings ringing and no stepper motor noises, also the dog clutch is superior to the Oldham I had. Waiting for clear skies to test things up.
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Re: Losmandy GM8 OnStep upgrade
Cze??,
RGB Elektronika supplies EZO 6.35 x 15.87 x 4.97 mm bearings in Poland - superior to what was in my Losmandy and still not too expensive. EZO Bearings was the most reasonable thing I found in EU supplies given the price for quality.
If I get it well, based on my serial number my Losmandy head is from 2004 (serial HGM 0450...) and had steel worms and two piece worm blocks - so some things might be better in newer mounts and might not need replacing.
Dominik
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Re: Losmandy GM8 OnStep upgrade
You need Belville washers for R4 size bearings (1/4” / 5/8”) which have an ID of 10.3mm (0.406”) and an OD of 15.69mm (0.618”) it that helps. ? David ?
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From: [email protected] [mailto:[email protected]] On Behalf Of Sebastian Kotulski
Sent: 23 September 2020 10:38
To: [email protected]
Subject: Re: [Losmandy_users_io] Losmandy GM8 OnStep upgrade ? Hi Dominik (Cze??)
Let me know if you find Belleville washers that fit Losmandy worm blocks. What kind of EZO bearings did you use?
Sebastian
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Re: Losmandy GM8 OnStep upgrade
Hi Dominik (Cze??)
Let me know if you find Belleville washers that fit Losmandy worm blocks. What kind of EZO bearings did you use?
Sebastian
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Thanks anyway! Yep I had it shortly after getting it. Seems to me that the ring on mine is just a bit too big. Like I said though it's really just a minor issue, cosmetic really, but if it's not addressed the guiding goes to pot. Rubbing is not so good.?
Jamie
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I see. Different design from mine. Sorry I can't help with that one.
BTW is that a vixen type dovetail with one flat side you have? I can see bite marks on the side.
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I think that yours is a G11. Mine is a GM811 so the issue is on the DEC which is a G8 axis. Looks a bit different than yours.?
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Yep. Attached an image where it would be rubbing if I didn't remove the ring:) Just about ready to start imaging the pinwheel galaxy. I circled the spot where it would be rubbing.?
Jamie?
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Is this what you see? Gap between worm block and ring.
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Chip Louie
Dave_Kentsbeer
David C. Partridge
Jamie Amendolagine