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Re: Craven Stretch Build

Posted: Thu Nov 03, 2011 2:39 pm
by GVardaman
Great onto, thanks!
Where did you get the anti-backlash nuts?
I hadn't even looked at McMaster Carr but I would bet they would have them,if anyone would!

Re: Craven Stretch Build

Posted: Thu Nov 03, 2011 6:47 pm
by AJ Quick
We will be selling the Anti-backlash nuts soon.

(Probably by Monday).

Re: Craven Stretch Build

Posted: Thu Nov 03, 2011 6:50 pm
by dalecraven
I finally got everything together. Shellac on all of the parts, lengthened the machine, all of the axes moving smoothly but slow, re-cut the top and added t-slots, added the 80/20 table supports, replaced the acme nuts with anti-backlash nuts. Here is a picture.

http://flic.kr/p/aBCfoX

The 80/20, longer leadscrew, and the aluminum pipe all came from McMaster. The anti-backlash nuts are from http://www.dumpstercnc.com. AJ will be selling them soon but if you order them you have to make sure to get the custom cut down flange option. Measure your original nuts.

I installed the router mount on the z-axis and went to install the router to check table flatness and tram and SNAP.. The router mount broke! I was all ready to make my first test cut. (Might have to get out the vice clamp!!!). I'll keep you posted on next steps.

http://flic.kr/p/aBCenn

Re: Craven Stretch Build

Posted: Thu Nov 03, 2011 8:11 pm
by Tommy LeRoy
Machine looks great! I did the same thing to my router mount, I think the resin used for this part needs to be substituted for something with a lower hardness that way it'll flex when being tightened I think it's too perfect of a fit open and when it gets tightened it stresses the last inch of the arm, that is exactly where mine broke, ideally this should be something like ABS or Aluminum, Smooth-On task 13 or Smooth Cast 60 might have a better resin for this purpose.

Re: Craven Stretch Build

Posted: Fri Nov 04, 2011 12:19 am
by AJ Quick
You may be right Tommy.

We do have a few router mounts made from a more flexible resin, but they are a little rough around the edges. I'll throw one of those in with Dale's replacement, perhaps he would be willing to be a Guinea pig? ;)

Re: Craven Stretch Build

Posted: Fri Nov 04, 2011 12:27 pm
by GVardaman
Ruh roh!

Sounds like something that could use some tweaking. I wonder what an aluminum replacement parts would costs?


Okay, looking for the anti-backlash nuts... :D

If I break my mount, I would also be interested in being a guinea pig for the more flexible resin version.

Re: Craven Stretch Build

Posted: Fri Nov 04, 2011 12:52 pm
by AJ Quick
We can't continue to send out replacements for everyone who breaks them. You must ensure that you don't overtighten them. A few of them have broken, but most have not.

Re: Craven Stretch Build

Posted: Fri Nov 04, 2011 1:48 pm
by dalecraven
As soon as it gets in, I'll start up with the prototype resin.. Since I have heavy thumbs I should be a good tester! :D

Re: Craven Stretch Build

Posted: Fri Nov 04, 2011 2:00 pm
by AJ Quick
This new resin is much much more flexible.

Re: Craven Stretch Build

Posted: Sat Nov 05, 2011 9:20 pm
by dalecraven
I started cutting my first project, a set of holiday cookie stamps. I had some problems cutting the circle handles out. I could not get the circles to interpolate smoothly. Let me know if you know some settings in Mach3 to look at. I can do x and y jog motions smoothly but when I have gcode running is seems jerky between steps. I changed the controllers to 1/8 step and is seemed a lot better but still a little jerky. With the new settings I cut out the Corian cookie stamp ends and they look pretty good..

THe project is one of the free monthly projects that Vectric puts up on there website to run on their software. If you have not looked at Vectric Software you should. I use Vcarve Pro and will probably end up getting Aspire some day.

http://www.vectric.com/

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