[nateman_doo]

I actually sheared it. Now I wish to replace it. Is an oldham the same as a lovejoy? They look slightly different, but I need something to account for the misalignment of my motor mount to shaft like the oldham does.

I found some anodized aluminum ones, but I am worried if I already sheared one I will do the same to another. Will the anodized aluminum hold up better to the non-anodized?

[Al_The_Man]

I only use aluminum helical couplers for encoders, for motors I use the stainless version, a bit more money, but they stand up to alot more flexing under load.
Al.

[pete from TN]

Check out some posts BY Ray AKA Himykabibble who has made some simple misalignment couplers on here. I think they are delrin and aluminum and apparently work pretty well. Sorry to hear you broke your mill.... peace

Pete

[nateman_doo]

I would rather buy one then make one. Any input on Anodized Alu, vs non anodized?

[SCzEngrgGroup]

I would rather buy one then make one. Any input on Anodized Alu, vs non anodized?

Anodizing has zero to do with strength - it's for appearance and corrosion protection.

Regards,
Ray L.

[mrcodewiz]

What size steppers and mounts? I bought some of these a while back to use on my G0704 and realized they were much too small but I plan on putting them on my X2 at some point. I bought 4 thinking it was just a half of the coupler but turns out it was the whole assembly for $4.50

[ame=http://www.amazon.com/gp/product/B000IL5G9G/ref=oss_product]Amazon.com: Huco Aluminum Oldham Blind Bore Coupler Clamp 1/4" x 5/16" Bore, 0.75" OD, 0.87" Overall Length(Pack of 1): Industrial & Scientific[/ame]

[nateman_doo]

3/8 motor & shaft.

[mactec54]

nateman_doo

You want to use the stainless couplings, the aluminum don't like the flixing, if you have to much misalignment

[nateman_doo]

But does the steel like being misaligned? I figured it would have more grief then the Aluminum. I think I just had the gibs torqued down too much?

[SCzEngrgGroup]

You must have some serious misalignment to cause a flexible coupler to actually fail! Get some Oldham couplings - they have sliding fits, not flexing, so no chance of fatigue. Though it is dead simple to make your own. I made a whole batch of them in a couple of hours from scrap.

Regards,
Ray L.

[photomankc]

If your couplers are failing then if you beef up the couplers your going to fatigue something else, probably more expensive. Get the Oldhams. The shafts can be way off and there will still be no stress on the motors and bearings, just more wear on the oldham center disk. McMaster-Carr sells them if you want them fast they can get them out to you straight away.

[TXFred]

Aluminum breaks faster because it fatigues diferently.

You can stress and unstress steel and stainless with a mild load millions of times, and it will be fine.

You do the same to aluminum, and even though each stress is minor in comparison to the total strength of the part, it will eventually break.

This becomes an issue in aircraft, such as the Hawaii Air flight that had the roof of the first class cabin fly off.

If you want a good selection of couplers, go to mcmaster carr. They have almost every size you can think of.
McMaster-Carr


Frederic

P.S. photomankc, you stole my old signature! :stickpoke

[photomankc]

Heh, I knew I read it somewhere! My wife loved it, thought it described what happens downstairs to a tee!

I'd say the Oldhams are cheap insurance and I don't see a lot of downside to them really. But I see what you mean with AL. It definitely does not like to bend around repeatedly even if it is minor.

[cornbinder23]

P.S. photomankc, you stole my old signature! :stickpoke

Its alright I like your new one better!!!!!!!!!

I'm a welder:wave:

JTCUSTOMS

[nateman_doo]

CRAP?! the other one just gave out too?! GRR!!!

[nateman_doo]

What about High-Misalignment Pinhole-Disc Shaft Couplings?
says it handles more misalignment then the oldhams @ McMaster.

[nateman_doo]

& while I am at it, anyone have any recommendations on waterproof limit switches? Thats how this whole mess happened in the first place.

[Al_The_Man]

I usually use the Honeywell 914C series, they have hermetically sealed cable connected.
ebay 150557606015.
Al.

[pete from TN]

Sorry to hear of your woes there buddy.... As far as waterproof limits goes. If you want to just buy them there are a bunch of options in a lever armed waterproof unit but they are pretty pricey. Another option for the do it yourselfer is to build something like the Limits Aaron Moss built for the Industrial hobbies cnc kits and turnkey mills. It consists of a machined aluminum housing with a stainless steel actuator rod that goes thru it horizontally across the top of it and inside the housing there are orings to keep the dust/crud/crap out and there is a spring loaded flag that get setscrewed to the shaft with a spring loaded setup on both sides. The actual switch is an optical setup that the flag trips and he made them dual switches so you have a left side and a right side on every axis which makes it easy to use a home/limit setup. Just do a search for IH limits and I am sure you will find a picture or two.... I have them on my machine two of which I bought from a nice fellow named Ray(Himykabibble) and I machined a third for my machine myself. The nice thing is that you can make these units with a long actuator rod that you can put stops anywhere along it for absolute control anywhere in the travel. It also makes for a relatively painless mounting. I am sure you could also make them with some typical lever arm actuated switches if you did not want to mess with the opticals.... peace


Pete

[nateman_doo]

Its ok. I will just make sure the switch is very well protected from runoff. I ordered the oldham couplers. Ill keep you updated.