Help to beef up K2-2514

[SPEEDRE]

OK , It has issues, we know that now, but. I've disassembled mine three times now, I've planed "new" ideas around the parts all to no real advantage. So, it's back to square one. My biggest issues are with, flexing of the bridge, and a lightweight R8 spindle. How can I defeat the flex?. How much and where to beef up. I need some help with that, I must be missing something in my concepts. HELP! And for the spindle the Mini boxes are too heavy for the current bridge I'll have to design one around the R8 profile I guess. Can anybody help with a direction to look at or provide any ideas I could use?

[joecnc2006]

can you post pictures of different aspects of your machine?

Joe

[SPEEDRE]

No I'm sorry, no digital cameras. It's on older model with 12mm rods and bearings, 3" Z travel. It has a 1/4" back plate to mount the Z between the 20mm main rods and bearing blocks. What if I spread the rods apart a little more, right now they 80mm on center and 490mm long. Doing the math it's like 301/8"" x 19 1/4" long. So as it goes across the table it's fine, not much flex at all. It is in the X axis that it sort of drags along and flexes a good .060-.080 as it machines thru 6061-T Alum. @ 10ipm & .020 depth cut. Those are estimates from when I first set it up years ago. I'd like to eliminate that situation. The rods are not supported in any axix.

[j9k]

i have the same machine with the 5" z axis. i only tried to cut aluminum with it once and decided to never do that again. the x-axis probably needs to get upgraded to supported rails somehow. i enlisted the help of a local machine shop to make a new 1/8" collet for my PC 7310 and it cost $80. but in the real world i guess that's cheap.

i guess a good analogy would be if you held two straws together parallel. the closer they are the more flex.

btw what size and shape bit are you using, rpm?

j9k

[SPEEDRE]

I used a Ryobi trim router for the motor and a 1/8th mill. It just dragged its way thru until, it started to gall up and chipped the faces of the flutes right off. Yes, I also believe supported rails are definitely a plus or at least finding a way to put the stresses elsewhere.