Hobbymat BFE65 Leadscrew info, fitting anti backlash nuts

[manofgresley]

Hi all

I run a HOBBYMAT BFE65 vertical milling machine c.1984. I am looking to fit anti backlash nuts, but i seem to have hit a problem, Does anyone in CNC land know exactly what the Lead-screws are? i have measured them at 14 mm outside diameter, single start with a 2 mm pitch per single evolution, the problem is i am having difficulty finding out if they are ACME, METRIC or TRAPEZOIDAL, and i can only find 3 mm pitch on the internet (TR14 3)

Any help on this subject would be very helpful.

Regards

Ray

[Lee Roberts]

Ray did you ever get an answer to this?

.Me

[manofgresley]

Ray did you ever get an answer to this?

.Me

Hi.

No i did not.

Ray

[mekanik]

If the pitch is metric the leadscrew is Trapazoidal(Trapazoidal is the metric version of Acme)
Not all the pitches are show on the charts i had a look @. I was looking for data for turning an M8 x 2 leadscrew and couldn't find it,fortunatelly i have a tap and will make the nut first and leadscrew to suit.
Mike

[manofgresley]

Many Thanks Mick.

I have not fitted backlash nuts yet, but this info will be valuable for the future.

Regards

Ray

[rnr107]

Hi Ray,
Why not replacing the leadscrew all together with a known diameter / pitch?
Trapezoidal screws are fairly cheap these days.

RNR

[mekanik]

It's all well and good doing that but as a rule there's an indicator dial on the end of it so you need to make a new one. i am replacing a 1mm pitch screw so bought 2mm pitch tap so can go off half a division of dial. As it's for the topslide it only gets used for doing facing cuts and infeed when screw cutting. you could get a 4mm screw and do the same.
Mike