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electrosteam
16th Jan 2020, 09:26 PM
My re-furbishment of a Kondia FV-1 CNC turret mill has the Z and Y axes operating under computer control.
The X-axis has got the ball screw installed and I need to assess the practicality of fitting covers before the table is mounted.

I purchased some bellows through Alibaba some time ago, but they don't fit.

Has anyone solved this problem and can recommend a solution ?

Thanks in advance,
John.

BaronJ
16th Jan 2020, 10:47 PM
Hi John,

Will those flat spring type covers work ? You can put them on without dismantling the shaft.

384291 384290

This sort of thing.

electrosteam
16th Jan 2020, 11:04 PM
Hi BaronJ,

The local (Sydney) price for identical lathe leadscrew covers is about AUD 1700, out of my league.
A search on Ebay, Alibaba and Bangood did not produce any results.

Do you have a source ?

I found Spiroflex in Germany, but I am sure their pricing would be beyond me.

I will contact my Alibaba supplier, but the ratios of min/max length and min/max diameter will make it difficult.

John

BaronJ
17th Jan 2020, 04:44 AM
Hi John,

Ouch ! That's a bit steep.

Regretfully No ! But I do know someone I can ask. I'll do that tomorrow.

You would think that with all the Chinese lathe manufacturing that they would be available as spare parts.

elanjacobs
17th Jan 2020, 04:27 PM
A search on Ebay, Alibaba and Bangood did not produce any results.
Not sure what you were searching for, but "lead screw cover" and "ball screw cover" on Alibaba definitely produce results

https://www.alibaba.com/product-detail/Steel-telescopic-spring-lead-screw-cover_62190221425.html?spm=a2700.7724857.normalList.30.13961dd3pUTeck
https://www.alibaba.com/product-detail/Nylon-CNC-machine-ball-screw-bellow_62238665195.html?spm=a2700.7724857.normalList.258.15f43720IMjsAW

BaronJ
17th Jan 2020, 09:12 PM
Hi John, Guys,

I've just spoken to Lee Spring and they can make them to order ! Much cheaper than $1700.

The link that Elanjacobs posted is much cheaper still !

https://metalworkforums.com/redirect-to/?redirect=https%3A%2F%2Fwww.alibaba.com%2Fproduct-detail%2FSteel-telescopic-spring-lead-screw-cover_62190221425.html%3Fspm%3Da2700.7724857.normalList.30.13961dd3pUTeck

electrosteam
18th Jan 2020, 08:44 AM
Guys,
Thanks for the responses, I guess my search techniques need some improvements !
I will follow up on the telescopic helices and let you know the outcome.

This does raise another issue though.
On the end not driven by the stepper, the screw is quite a bit shorter, enough to come inside the saddle at maximum traverse, and is not supported by a bearing.
The lack of length appears to come from simply duplicating the lengths of the original leadscrew, and that allowed for a shaft extension from the table feed power unit.

I could remove the screw from the mill, add a shaft extension and a closure cap to the table end.
The cap would enable a mount point for the helix end and ensure the table cannot traverse inside the saddle on that side.
An alternative would be a spigot on the cap that lines up with the screw

A mate come up with an idea during a workshop session last night.
What about plastic lathe style leadscrew half-nuts spring-loaded onto the screw ?
Easy (relatively) to inspect, clean and remove/replace.
A brilliant suggestion.

Lots for me to do,
John

electrosteam
13th Feb 2020, 11:45 AM
Followed Alibaba up and placed an inquiry.
Got a response the next day with the comment "will contact you soon".

As Chinese NY was starting, I patiently waited.
Then, Coronavirus struck and nothing to date.
So, I have added some tapped holes to the saddle that could be useful 'some day', and proceeding to mount the table without ballscrew covers.
(which is the way it was before)

Hope to resolve the question eventually.
John