[Marti]

The ballscrew is attached to the gantry.

thanks ... I am doing a belt with the moving gantry and I wanted to stablize it from the bottom and thought of running a metal rod from end to end and thought you might have the motors mounted on the axis with the rod for support

[jevs]

Did you float the ends of your ball screws or use the same design as the datacut with a lock nut and double angular contact bearings on each end?

If you did the same as the datacut design, did you machine the ends to the datacut specs or something else since the ball screws are metric?

Did the ball screw supplier machine the ends for you?

[MRM RCModels]

Did you float the ends of your ball screws or use the same design as the datacut with a lock nut and double angular contact bearings on each end?

If you did the same as the datacut design, did you machine the ends to the datacut specs or something else since the ball screws are metric?

Did the ball screw supplier machine the ends for you?

Used the same design as the data cut. I had a local shop machine the ends for me. I re-drew evening in inches.

[jevs]

If you were doing it over, would you just go with the Kerk screws and VHD nuts or use ball screws again?
The Chinese ball screw guys do offer double ball nuts (zero backlash), did you consider these at all?

Do you remember what they charged you to machine the ends?

Machined end lead screws and VHD nuts from Kerk are about $850

Chinese ball screws are much cheaper depending on the machining cost.

How did you make your wipers and are they working good?

I am stuck on my design a bit until I figure out what to do with the screws and nuts...

[MRM RCModels]

If you were doing it over, would you just go with the Kerk screws and VHD nuts or use ball screws again?
The Chinese ball screw guys do offer double ball nuts (zero backlash), did you consider these at all?

Do you remember what they charged you to machine the ends?

Machined end lead screws and VHD nuts from Kerk are about $850

Chinese ball screws are much cheaper depending on the machining cost.

How did you make your wipers and are they working good?

I am stuck on my design a bit until I figure out what to do with the screws and nuts...

I used zero backlash Chinese ballscrews. Haven't had any problems. I could sell you my solid model. Let me know if interested.

[jevs]

I am actually pretty far along on modeling it already. Like you I changed a lot. Due to different rails and stuff our models would be different even though very similar. I can't imagine building this thing without modeling it first. Even though it looks similar to the original design, I had to make small changes to about every part so far

Like you I plan to use DMM servos.

[jevs]

I read earlier in your post that you were having issues with resonance and were making a damper.

Did you use a 1605 ball screw for the long axis X (by data cut plans)? The reason I ask is that your nut in the pictures does not look like a Chinese ball screw nut.

Did you need a damper after you switched to DMM servos?

I am just trying to decide if a 16mm ball screw is adequate for the long axis or if I should go larger.

[mactec54]

jevs

You would not use a damper with the servos, a damper is only needed for steppers

Use as big a diameter ballscrew as you can fit, 20mm minimum 1610 is a good pitch to use 1605 would be half the speed of a 1610

[jevs]

jevs

You would not use a damper with the servos, a damper is only needed for steppers

Use as big a diameter ballscrew as you can fit, 20mm minimum 1610 is a good pitch to use 1605 would be half the speed of a 1610

I just got a response from linearmotionbearings2008 and 2010 and 2510 do not have a double nut option, only 2005 and 2505 The lead screw would really be zinging to get any speed out of those? Think they would go fast enough with the servos without reaching critical speed (X is 53" between bearing faces)? These will be belt drive 1:1 (unless another ratio is needed).

I am not sure how OP is getting zero backlash from a single ball nut? My understanding was that all of these have some backlash? I know you can change the balls to lessen it, but it's still not zero...right?

[mactec54]

jevs

I don't no how good the Chinese ballscrews are, good brand name screws that have a single nut ballscrews have zero backlash, if you are serious about your build then you would get ground C5 grade ballscrews, the ballscrews you are looking at are a rolled screw, minimum of a C7 grade not that great, ok for cutting wood, it just depends what kind of accuracy you want

[LazyMan]

"Zero backlash" rolled ball screws should really be called reduced clearance ball nuts. The backlash can below may be around .001" You could buy two single ball nuts and use a spring for preload. This will give you true zero backlash and compensate for lead deviations an wear. This is the only way to get true zero backlash with a rolled screw without binding.

[jevs]

I am not using ball screws. I was going to use double nut ball screws, but those Chinese ones don't come in the right pitches for me with a double nut. I am going to use the Haydon Kerk VHD nuts and scews. They are more expensive though. No balls to get gummed up though and better pitch selection...

[LazyMan]

Do you have any updates on your progress with your build? I m very interested to know how well the VHD nuts perform for you.

[jevs]

I have them, but I have not installed them yet. It is going to be awhile. I have too many projects going, so I only get to dabble with this a little here and there. Once I get done building this car I am building, I will be more on the router again. I have been working on the schematics here and there, I have all the CAD models done except I am switching to much better timing belts than the XL. So, I have to change the pulleys in my drawings. Anyway, I have been getting really sick of Chinese junk lately, so I am glad I went with the VHD. They do look nice and were machined well (I did check the dimensions), but I have not installed them yet.

[MRM RCModels]

Hey guys. I know it's been a while, but the router is for sale on ebay. Got to make room for more projects. Going for cheap too!!!

http://www.ebay.com/itm/-/151733398072?

[diyengineer]

That's a nice machine!

[ger21]

Got to make room for more projects.

The auction says to make room for your wife's car?

[MRM RCModels]

The auction says to make room for your wife's car?

Lol.

[Devastator]

The auction says to make room for your wife's car?

Maybe that's the project.

[SatanKlawz]

Do yourself a HUGE favor and pull the auction right now! You WILL ABSOLUTELY REGRET this decision. Trust me.... I am in the same boat. I sold mine in 11' and have been thinking about it ever since and am now 5k back in a new build. I would have bought that in a heartbeat if it was for sale when I started buying parts earlier this year. You have so much time in that thing that you will never get back. This is why it has taken me so long to get back into a build is because I knew the amount of time it takes to put something quality together. last time, DON'T DO IT!

After watching the video in the auction I can see that you have passion for this and the enthusiasm that you show when something turns out good is awesome. Trust me on this, unless you are already building a better machine or cooler project it is impossible to replace that feeling of knowing that YOU did all of that when it turns out a great part. I miss that sense of pride about the machine that I sold very much and I know that you will as well.