Cuts are not perfect!

rsetina
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Re: Cuts are not perfect!

Post by rsetina »

Greatly,

That was my first thought too, to align the gear with the track. May not solve the problem but it just doesn't look right. And like others have said, a quarter inch of play should be very easy to track down. It wil be interesting to find out what it is if it's not obvious. Good luck.
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Leo
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Re: Cuts are not perfect!

Post by Leo »

The gear and rack needs to have better alignment - but I don't believe that is the problem.

There is a HUGE mechanical issue.

If you bought the Lagacy machine from a dealer of from Legacy - they should fix that and it be covered under warranty.

Movement of 1/4 inch is monumental.

I would tell you that 1/32 movement is a SERIOUS issue.

I will take this as a seriously bad review on Legacy.
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4DThinker
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Re: Cuts are not perfect!

Post by 4DThinker »

The gear being out of line with the rack suggests it may have a loose set screw. Loose set screw will allow the gear to rotate enough to account for the 1/4" play you have found. Re-align the gear. Put its set screw back in tight with a drop of lock-tight on it. Check for play again.

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Re: Cuts are not perfect!

Post by PaulRowntree »

There is a flat on the shaft, and the lockscrew is on the flat, so I will bet $0.05 that the problem is elsewhere (but still : fix that pinion! You are ~doubling the localized mechanical stress if not fully engaged)

It must be a trick of perspective (or old eyes), but it looks like the rack teeth are a finer pitch than the pinion.

Any chance that the wiring is not 100%? One coil not being driven, bad contact, broken wire, blown driver, .... Measure the resistance of the two coils in the motor after disconnecting from the driver ... they should be a few ohms and equal. Try swapping the X&Y cables around : does the backlash remain on Y?
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martin54
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Re: Cuts are not perfect!

Post by martin54 »

Although you have had some good suggestions I would be careful what you actually do if the machine is under warranty if the machine has come with the pinion fitted like that then who knows what other problems may exist & the manufacturer or distributor should really be giving the machine a complete once over to ensure everything is correct as they should have done before the machine was shipped.

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Re: Cuts are not perfect!

Post by PaulRowntree »

That is a really, really good point Martin54; that never even occurred to me.
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martin54
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Re: Cuts are not perfect!

Post by martin54 »

I'm quite often the same Paul, everyone tries to help out which is great but we don't always think about the consequences.
These machines are expensive, I know nothing about this particular manufacturer but I have come across manufacturers/suppliers who would go to almost any length to avoid their warranty responsibilities. Not for one minute saying these people are like that but best not to take chances if possible.

Oh & it's just Martin Paul, the 54 is suppose to be my IQ but I forgot to put the dot between the 5 & the 4 :oops:

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Re: Cuts are not perfect!

Post by pencrafter »

Greolt. you were right on the money. Your clue helped me to fix the issue. The pinion was too far out and not riding on the track firmly. I woe you one. Thanks a million.

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Re: Cuts are not perfect!

Post by Greolt »

Well if that issue fixed it all on its own then I am glad.

But it does surprise me. I was only pointing that out as it may have been a clue leading to the main issue.

Anyway if all is good then that is great. Now you can get on with those projects you have in mind. And post pictures. :D

Greolt

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