New Machine Build- What did couplers did you drive your acme screws with?

[nearbeer]

Inching every closer to building my JGRO and before I pull the trigger on dumpster CNC parts, I wanted to get your opinion on what other options that may be out there.

As the title states, I am using 1/2" ACME instead of all threaded rod. I plan on using stepper motors from HobbyCNC and have been trying to figure out how the screws are driven by the motors. I understand that some type of coupler is required but having not see many detailed drawings of couplers, I want to know what you may have used in your build. Thanks for your time.

In search of my next cold one,

NearBeer

[CarveOne]

Originally Posted by nearbeer Inching every closer to building my JGRO and before I pull the trigger on dumpster CNC parts, I wanted to get your opinion on what other options that may be out there. As the title states, I am using 1/2" ACME instead of all threaded rod. I plan on using stepper motors from HobbyCNC and have been trying to figure out how the screws are driven by the motors. I understand that some type of coupler is required but having not see many detailed drawings of couplers, I want to know what you may have used in your build. Thanks for your time. In search of my next cold one, NearBeer

I used DumpsterCNC anti-backlash nuts and DumpsterCNC ACME screw to 1/4" shaft couplers on my Solsylva 25x37 build. It started out with 1/2-10 1 start screws and now has 1/2-10 5 start screws on it.

CarveOne

[pencilneck]

I'm using these:

http://www.cncrouterparts.com/produc...products_id=51

[doorknob]

I am in a similar situation, seeking a set of couplers to go between 1/4" stepper motor shafts and the 3/8" machined end of some leadscrews.

I have seen advertisements for compression-style couplers made out of materials such as aluminum, stainless steel, and Delrin (plastic).

While I understand that Delrin or similar materials are often used, quite successfully, for leadscrew nuts, I'm a bit unsure of whether or not it is wise to use that material for a coupler (as used by dumpstercnc as shown at http://www.dumpstercnc.com/couplers.html ) - what worries me is not so much the possibility of slippage of the shaft under load, but rather the possibility of damaging the couplers by stripping the threads used to hold the tightening screws by tightening them too much.

The dumpstercnc page advises:

Tighten the screws about 1 turn past snug. Do not over tighten, very little torque will clamp these on really tight.

Has anybody actually had problems due to overtightening those screws, or am I needlessly worrying about this?

The price for the Delrin couplers is attractive compared to the pricing that I'm finding for aluminum helical flexible couplers (on eBay, at least).

The cncrouterparts.com coupler looks like a good one, however it does not appear to be available in the size that I require.

[Woodbutcher-59]

Hi Doorknob,

I originally had the Delrin couplers on my homebuilt router, had to tighten the crap out of them and still had slippage issues. These were 1/4" to 1/4" size.

I ended up swapping them for the helical Aluminum type and have had no issues since. Well, not with the couplers anyways....

I do continue to use the AB nuts from dumpstercnc, no problems there.

Hope this helps...

Jeff

[doorknob]

Woodbutcher-59,

Yes indeed it does help, thanks...