Meade DIY Wedge

[mojo]

Has anyone seen any designs for a Meade-like LX200 wedge?
I have access to a CNC machine, and I'd like to build a wedge myself. But instead of copying Meade's design, I'm sure there must be a better design than theirs.

[Orion]

Terry if you already know what the wedge looks like, couldn't you come up with your own design :confused:

[mojo]

i know what a meade wedge looks like. but i'm not sure if that is the best way to do it.

i like this design (http://www.aptastro.com/products/wedge.php). i think it's simple to adjust and easy to reproduce.
I'm sure there are many designs. I just haven't seen enough to form an opinion of the best design.

[acropolite]

I was thinking the same thing, getting some aluminium plate and having it laser cut and assembling. I don't think there would be much to it apart from a bit of drilling and maybe some lathe work. Saw this nice home made effort on the LX90 Yahoo forum

[mojo]

Yeah that's what i'm talking about. That doesn't look too difficult to make.
It's really just four main pieces that get bolted on. With the only technical bit being the threading for the adjust screw at the back. I've looked at a few variations and that design is as simple, sturdy and reproducable as there is.

He's done a really nice job with it too. Did you ask on the LX90 forum if there are plans for that one floating around?

[acropolite]

I tried to find the guy who made it, but there was no mechanism to contact him. I suspect that it's a copy/improvement of the standard Meade design. I will post a request in the group and see if the builder replies...:D

[mojo]

Thanks :) I'd do it myself, but those closed yahoo groups are so anti-social.

Otherwise, i'll keep designing the wedge and post the design when i'm done. It's just sooo much easier plagiarising :)

[mick pinner]

Hi Mojo, just to simplify things a bit, if you are going to use the wedge on a permanent pier or are not travelling to far from your original viewing site then the wedge does not have to have an adjustable latitude plate, just have it fixed to your latitude as they do with the Meade 16" pier, a lot less work to get one up and running while you work on a more sophisticated design. Just a thought. Mick.

[mojo]

Mick: I was thinking that. Just make the thing out of wood and it would probably do. But I have an urge to make the real thing.

Phil: Thanks!

[Comet Hunter]

I think I've posted this link before for Tony when he was going through his 10" LX200 faze :P... For all things Meade check out MAPUG (http://www.mapug-astronomy.net/AstroDesigns/MAPUG/ArhvList.htm) - Meade Advanced Products Users Group. Heaps of info collected there, including wedge designs (mostly commercial though). The Baltic Wedge (http://www.mapug.com/pages/Baltic_Wedge/Baltic_Wedge.html) might give you a few ideas for your own design... Plus there's also good old Google.....

I did find some plans somewhere along the line though..... I'll have a dig around to see if I can find the link.

[mojo]

ooh thanks. nice links.

[Comet Hunter]

Found it :D

Here (http://website.lineone.net/~tony.floyde/HOME%20PIER.htm). It also includes plans for a pier.

It may need a few modifications depending on your latitude....

[mojo]

thanks Andrew. Found the AutoCad drawing of it yesteray. MAPUG is a good resource. nice find.

[Comet Hunter]

No worries Terry, I'd be interested to hear how you go with construction + costs etc once your finished :)

[Stevo69]

Hi mojo, I was just browsing the old posts and located this one. Did you make any progress with your own wedge? I agree with you, there has to be a cheaper and better way to make them. The commercial ones seem to be "over engineered".

[robgreaves]

I built one many years ago in the UK. Very simple, but extremely sturdy. I'll describe it:

40mm thick aluminium base plate. 20mm stainless axle running in block bearings, tilt plate 20mm thick, with radiused edge to suit 20mm axle which was bolted to it. At the back were a pair of stainless turnbuckles, with rod end bearings each end. One end bolted to fixed plate, one end to tilt plate. The base plate had blocks with azimuth adjust screws each side, and a fixed post on the pier/tripod to to act against. Put a sheet of 3mm thick Teflon below it to slide on.

If I can find a pic, I'll post it.

Someone did see it at one of the star parties and blatantly ripped it off (not that I mind - he's a friend!) :)

The link is here: should give you the general idea.

http://www.zyworld.com/Domehome/Observatoryies/FULL/32.JPG

It's rock solid, and won't budge. The weak link will then be the scope forks and your tripod.

Regards,
Rob.

[mojo]

I completely forgot about the wedge project, Steve. I seriously can't remember what design I settled on - When I find it, I'll post it. I remember even calculating the forces on the wedge based on an LX200 bolted onto it - because I had no idea how strong (thick) the aluminium had to be to ease my paranoia that I'd find a pile of glass and mirror on the concrete due to a failed wedge :whistle:

I like that wedge, Rob. It does look sturdy. It doesn't look like those stainless steel turnbuckles are going to snap off any time soon. Do you remember what diameter they are?

[5ash]

Hi mojo ,
I posted some pics of my homemade wooden wedge on IIS over 2yrs ago.I made it out of 38mm thick plywood that i fabricated out of two 19mm sheets glued and nailed together.I think wood is a good medium for a wedge as it damps down vibrations . It has been set up on the pier as shown for 2 yrs and has not been adjusted in the meantime.I use it for astrophotography and have managed up to 2-3 minute unguided shots at f.6 within the limitations of the drive.Some pics are therefore pinpoint and others show slight trailng due to periodic erreor in the drive. However it does demonstrate that wood can sucessfully be used.By the way it cost me about $20 to make all up.See pics below.
regards philip