Down feed backlash trouble

[2vieira]

Hi everyone, my 7" shaper machine has a great problem...BACKLASH, i mean, in the tool feed screw of the down feed, and it is huge as much as possible, about to 1,5mm. The question is that is not possible to work with ths kind of problem, regarding the working process of a shaper machine, cause the resistence force at the moment of the stroke is exactly upward. I think i will have problem to feed down cause the backlash of the tool feed screw will allow the tool post go up, not shearing the workpiece freely but adding aditional step to shear the workpiece. What do you think about it? Im right in my collocations? What should i do? Any help?
Thanks
Robson

 

[DAT510]

Welcome to H-M Robson.

What Brand and Model of Shaper do you have?

Do you know where the excessive backlash is coming from? Worn Leadscrew? Worn Nut? Somewhere else?
It will help us point to possible solutions.

 

[woodchucker]

1.5 mm does not sound too bad. in general we always move in one direction to control backlash.
so if going forward or down, we would back it out past the point and then move forward or down.
so it's less of an issue.

But I would be happy with 1.5mm.

 

[Ulma Doctor]

The feedscrew and nut are most likely worn.
It is possible to remove one of the downfeed gib screws and replace it with a thumb screw. The thumb screw would act as a locking device by exerting pressure on the downfeed dovetail, mitigating the backlash issue

 

[C-Bag]

The feedscrew and nut are most likely worn.
It is possible to remove one of the downfeed gib screws and replace it with a thumb screw. The thumb screw would act as a locking device by exerting pressure on the downfeed dovetail, mitigating the backlash issue

I added two locking handles to mine an it got rid of the drift while cutting. Ultimately I’m going to replace the nut with one made out of Delrin. The cross feed nut and lead screw are knackered too but that doesn’t effect things like that downfeed.

 

[benmychree]

The feedscrew and nut are most likely worn.
It is possible to remove one of the downfeed gib screws and replace it with a thumb screw. The thumb screw would act as a locking device by exerting pressure on the downfeed dovetail, mitigating the backlash issue

Generally, the gibs on the downfeed on shapers are kept pretty tight, so that the slide will not creep when cutting, mostly, backlash is irrelevant.

 

[Ulma Doctor]

I added two locking handles to mine an it got rid of the drift while cutting. Ultimately I’m going to replace the nut with one made out of Delrin. The cross feed nut and lead screw are knackered too but that doesn’t effect things like that downfeed.

I have some black delrin left over from when I made the cross slide nut for my Shenwai SW900B, i’d be happy to share with you.

 

[C-Bag]

I have some black delrin left over from when I made the cross slide nut for my Shenwai SW900B, i’d be happy to share with you.

Thanks Doc I appreciate that. I’ve got the material, just swamped with the ever expanding gottado list. My formula for triage is if it still functions ok it’s on the wannado list. If the locking handles didn’t work it would have gone close to the top of the gottado’s.

 

[2vieira]

Welcome to H-M Robson.

What Brand and Model of Shaper do you have?

Do you know where the excessive backlash is coming from? Worn Leadscrew? Worn Nut? Somewhere else?
It will help us point to possible solutions.

Hi guy,
It seems the backlash is in the leadscrew cause i measured the pitch of that in three positions achieving significant differences. The machine is a copy of any famous shaper cause the ram has squared way like the Atlas, the body looks like the Rhodes, in sumarize, i don know the brand the machine.
Here i attached some pics you see.
Thanks

 

[2vieira]

1.5 mm does not sound too bad. in general we always move in one direction to control backlash.
so if going forward or down, we would back it out past the point and then move forward or down.
so it's less of an issue.

But I would be happy with 1.5mm.

Hi friend,
Are you serious? I thought it wolud be an absurd backlash. Huahuahua.
I got your appointment about to always move in one direction, and i use to do that.
So i very happy to own 1,5mm of backlash.
Thank you