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Mirror O Matic


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Hi Everyone,

I am planning to build a Mirror-O-Matic machine, but since the designer Dennis Rech is not responding to emails anymore, I would be very grateful to anyone who could kindly share the plans of the machines you've built. Anything would be helpful. Images, plans, cur lists, advice etc.

 

 

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I have two larger MoM's in my workshop(up to 20")
Most probably I would not build a MoM anymore if I'd start all over again.  I would go for a fixed post grinder. Very easy to build.
This site has lots of info about such fixed post grinding machines.

Edited by Chriske
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On 19/07/2021 at 17:43, skybadger said:

Did you find the group's.io forum for MoM ? It all used to be on yahoo groups and then moved over. 

It doesnt exist anymore. I did download the archive, nothing much in it though.

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On 22/07/2021 at 14:28, Chriske said:

I have two larger MoM's in my workshop(up to 20")
Most probably I would not build a MoM anymore if I'd start all over again.  I would go for a fixed post grinder. Very easy to build.
This site has lots of info about such fixed post grinding machines.

I have interacted with Mr Waite a few times. However since the past year he hasn't been replying and I kind of tend to fear the worst when that happens.

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On 22/07/2021 at 14:28, Chriske said:

I have two larger MoM's in my workshop(up to 20")
Most probably I would not build a MoM anymore if I'd start all over again.  I would go for a fixed post grinder. Very easy to build.
This site has lots of info about such fixed post grinding machines.

also, i would love to read/view your experiences of the MoM, especially the figuring. May i please know how do you generate the initial sagitta? any details you could give me, i will be very grateful.

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A few years back we made 3 MoM's. Two that can handle 20" mirror and a third one capable of grinding a 10" mirror.
We built the two larger machines in my workshop. They’re standing side by side and together with my best friend Marc we grinded lots of  mirrors with it. That small machine we made it to install it in Marc's garage, so when he was at home he could continue working with his small MoM at home.
We installed peristaltic pumps to automate these large MoM's. Every grit has it's own pump system. Feed speed of the slurry is done by electronics. The containers continuously mix the slurry to keep it homogeneous. The MoM's can be left alone for a longer time as there is a safety built in. When the containers are near empty the machines do stop automatically. The electronics part of MoM's project was made by Guy. Sadly enough he left our ATM-group.
Anyway, only grit #12
0 was done manually because the peristaltic pumps couldn’t handle that larger grit.

The reason for these two MoM's was simple. We didn’t want to spend to many hours grinding on a mirror. We started grinding early '80 and made 'a few' mirrors/telescopes. So we decided to work on more complex systems like for example a Schupmann telescope. But first we wanted to build a Stevick-Paul. A Gregorian telescope was already finished and awaits a coating session...
Again, long grinding and polishing sessions are out of the question, finishing a say 10" mirror took us about 3 days. We prefer to spend more time on building/tuning the scopes itself, and obeserving of coarse. While grinding we only use 3 grits btw and do not clean in between them. Only for polishing we do clean of coarse.
Sadly enough my best friend Marc passed away jan'20.(I knew the man for almost 40 years). And since then I didn’t touch the MoM's at all. Only a  few weeks back now I'm thinking of restarting using my MoM. But first I need to remove that second one. That will be a very difficult task...

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On 24/07/2021 at 13:07, Chriske said:

A few years back we made 3 MoM's. Two that can handle 20" mirror and a third one capable of grinding a 10" mirror.
We built the two larger machines in my workshop. They’re standing side by side and together with my best friend Marc we grinded lots of  mirrors with it. That small machine we made it to install it in Marc's garage, so when he was at home he could continue working with his small MoM at home.
We installed peristaltic pumps to automate these large MoM's. Every grit has it's own pump system. Feed speed of the slurry is done by electronics. The containers continuously mix the slurry to keep it homogeneous. The MoM's can be left alone for a longer time as there is a safety built in. When the containers are near empty the machines do stop automatically. The electronics part of MoM's project was made by Guy. Sadly enough he left our ATM-group.
Anyway, only grit #12
0 was done manually because the peristaltic pumps couldn’t handle that larger grit.

The reason for these two MoM's was simple. We didn’t want to spend to many hours grinding on a mirror. We started grinding early '80 and made 'a few' mirrors/telescopes. So we decided to work on more complex systems like for example a Schupmann telescope. But first we wanted to build a Stevick-Paul. A Gregorian telescope was already finished and awaits a coating session...
Again, long grinding and polishing sessions are out of the question, finishing a say 10" mirror took us about 3 days. We prefer to spend more time on building/tuning the scopes itself, and obeserving of coarse. While grinding we only use 3 grits btw and do not clean in between them. Only for polishing we do clean of coarse.
Sadly enough my best friend Marc passed away jan'20.(I knew the man for almost 40 years). And since then I didn’t touch the MoM's at all. Only a  few weeks back now I'm thinking of restarting using my MoM. But first I need to remove that second one. That will be a very difficult task...

I absolutely loved your reply because as i read through it, I was visualizing both of you working on the machines. My heartfelt condolences for your loss because it takes a really long time to overcome the grief of loosing someone you knew for 40 years. I am always asking for guidance on the forums because I want to be one of the new generation ATM'er who can carry forward the legacy of you seniors. I am grateful for the guidance that you all provide. Below are two pictures of my "fresh out of the oven" White Portland Cement Tool for polishing. Please do give your CC.
I am also looking for copies of the entire set of the Telescope Making Magazine and ATM by Ingalls (not sure if I can pay though). I know thet even though they are old, the content in them are nothing less than treasures.

 

 

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