cutting inside cut

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Just Starting
Posts: 35
Joined: Sat Jan 23, 2016 5:10 pm
Model of CNC Machine: CNC Shark v21
Location: Memphis, U.S. of A.

cutting inside cut

Post by Just Starting »

ha folks
HAPPY NEW YEAR
ok this is whats happening
ive been cutting signs so really didn't notice.
also haven't cut from Thanks Giving till New Year
cnc shark 24x24 table-dewalt router- .25 em bit (sharp)
post processor (cnc shark-USB 3D contour inch)

i cut a circle 2.75 inside cut (building a carriage for a smaller router)
finished cut 2.68-cut a square 3x3 finished 2.95x2.98 also inside cut.

what am i missing here?
thanks
otto
oluhm@bellsouth.net

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Rcnewcomb
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Re: cutting inside cut

Post by Rcnewcomb »

Can you post the file? Oftentimes in these situations the tool diameter in the tool database is different than the tool name, or a different tool was used in the router than was specified in the cut file.
- Randall Newcomb
10 fingers in, 10 fingers out, another good day in the shop

Just Starting
Posts: 35
Joined: Sat Jan 23, 2016 5:10 pm
Model of CNC Machine: CNC Shark v21
Location: Memphis, U.S. of A.

Re: cutting inside cut

Post by Just Starting »

Sure
I'll get it to ya tomorrow
Thanks
Otto

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FixitMike
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Re: cutting inside cut

Post by FixitMike »

It can be tool and machine deflection. What happens if you run the cut a second time so there is only a slight amount of material removed?
Good judgement comes from experience.
Experience comes from bad judgement.

ger21
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Re: cutting inside cut

Post by ger21 »

If you were climb cutting, try conventional.
Gerry - http://www.thecncwoodworker.com

Just Starting
Posts: 35
Joined: Sat Jan 23, 2016 5:10 pm
Model of CNC Machine: CNC Shark v21
Location: Memphis, U.S. of A.

Re: cutting inside cut

Post by Just Starting »

yep
I did run a second cut.
it ran along the same track

Just Starting
Posts: 35
Joined: Sat Jan 23, 2016 5:10 pm
Model of CNC Machine: CNC Shark v21
Location: Memphis, U.S. of A.

Re: cutting inside cut

Post by Just Starting »

router clamp cnc.crv
(223.5 KiB) Downloaded 137 times
Rcnewcomb
here's the file
otto

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Adrian
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Re: cutting inside cut

Post by Adrian »

Tool sizes look ok. Is the machine properly configured? If you tell it to move one inch does it move exactly one inch etc?

Most likely going to be deflection due to flex in the machine itself or slop somewhere if it's configured correctly. Sharks aren't the most robust of machines so it might be worth slowing the feed rate down.

Just Starting
Posts: 35
Joined: Sat Jan 23, 2016 5:10 pm
Model of CNC Machine: CNC Shark v21
Location: Memphis, U.S. of A.

Re: cutting inside cut

Post by Just Starting »

Rcnewcomb wrote:Can you post the file? Oftentimes in these situations the tool diameter in the tool database is different than the tool name, or a different tool was used in the router than was specified in the cut file.
Attachments
router clamp cnc.crv
(223.5 KiB) Downloaded 99 times

Just Starting
Posts: 35
Joined: Sat Jan 23, 2016 5:10 pm
Model of CNC Machine: CNC Shark v21
Location: Memphis, U.S. of A.

Re: cutting inside cut

Post by Just Starting »

ger21 wrote:If you were climb cutting, try conventional.
i'll give it a shot
thanks
otto

Just Starting
Posts: 35
Joined: Sat Jan 23, 2016 5:10 pm
Model of CNC Machine: CNC Shark v21
Location: Memphis, U.S. of A.

Re: cutting inside cut

Post by Just Starting »

Adrian wrote:Tool sizes look ok. Is the machine properly configured? If you tell it to move one inch does it move exactly one inch etc?

Most likely going to be deflection due to flex in the machine itself or slop somewhere if it's configured correctly. Sharks aren't the most robust of machines so it might be worth slowing the feed rate down.
that is a great answer. your right about the shark too.
i'll recheck the configureation
thanks
otto

Just Starting
Posts: 35
Joined: Sat Jan 23, 2016 5:10 pm
Model of CNC Machine: CNC Shark v21
Location: Memphis, U.S. of A.

Re: cutting inside cut

Post by Just Starting »

Adrian wrote:Tool sizes look ok. Is the machine properly configured? If you tell it to move one inch does it move exactly one inch etc?

Most likely going to be deflection due to flex in the machine itself or slop somewhere if it's configured correctly. Sharks aren't the most robust of machines so it might be worth slowing the feed rate down.
adrian
you where absolutely right about robust. i slowed the feed down to 50 then when cutting i slowed it down to 25% and it did great. i was cutting a .75 sheet of clear plexi for a smaller router holder on this machine. you got to pay to play

thanks to everyone for the good advise
otto

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