Sieg bench mill mod.Increased Z axis mod

[bazmak]

I have read many threads on mini mill mods and i have one in mind
The mill is fairly new to me so please any advice would be helpful
The mill has approx 8" of Z travel which i found restrictive when i wanted to skim the ends of the angle plate.The quill travels down until it hits the table with lots of rack left.Does anyone see any problems if i fit a 3" x 1" x 6" lg
spacer plate between the column and base.There is plenty of rack,the torsion bar is OK and the heavy sliding stop will clear.I can also remove the silly rubber stop at the top of the column and gain another 1/2".The slot in the torsion bar then acts as the stop and still ok with the rack.Z will be increased
from 8 1/4" to a more useful 9 3/4".There is a lot of quill travel wasted at
the table level.The fixed column is very rigid at the moment,does anyone
have any thoughts on increased flex due to the plate.At the end of the day i have nothing to lose only time and cost, not a problem,can always go back to original.Any comments welcome Regards barry

 

[velocette]

Hi Barry
You can gain a little more if you use a collet that fits directly into the spindle.
An accurately machined block under the column base and longer bolts will be a useful addition and any flex will be in the column itself.

Not being impressed with the performance of the spring loaded quadrant I would suggest that you ditch it and fit an "Air Spring" instead.

Eric

 

[goldstar31]

I suspect that this pillar( your casting) will rock about like a tree in a gale. I suspect a chatter finish and probably chipping the teeth on your end mill. My opinion and if I am wrong, my apologies!

The sounder alternative therefore is to use the old Advance lathe as a horizontal mill and not using an end or slot mill at all. Baron described a flycutter a bit back and I can assure you that simple though it is, it works admirably. If you knock the edge off of the cutter, you can soon put it back.
I have one of these, I made it up yonks ago but put three stations for the tool bit to sweep different diameters. It wasn't my invention or anything pompous like that, it was straight out of Martin Cleeve in Model Engineer who modified the early Myford on which your Advance lathe is an excellent copy!

If you recall, this all follows what was on my recent e-mail about Cleeve's Turrets without Milling.

**********************************************************************************

That brings me to a wider question. Is this Australian lot of very clever model engineers still about? Again, are old volumes of Model Engineer still about in clubs, workshops or libraries? We- that is the Oz bunch, Jim Early from the USA and myself ran into copyright issues not so long ago. Jim is dead, I'm not far off that but if this sort of stuff is still available it may be ancient but it is still gold dust.

Meantime, I'm having to concentrate on other things.

Cheers

Norman

 

[velocette]

Hi
There is a discussion on Home Shop Machinist on the same job

http://bbs.homeshopmachinist.net/threads/65830-Mini-mill-riser-blocks.

A few good posts amongst the dross

Eric

 

[purpleknif]

I have an extended rack for an X-2 you can have for the cost of shipping.. Message if interested.

 

[bazmak]

Thanks velocette,read the posts with interests.And i was worried about
increasing flex by introducing a 1" high solid block.I think i will join them
just to let them know what i think.Laughable to think that they think they can pack the column 6" on tube
Thanks for the offer purlknife but i dont have a problem with the rack,just thought an extra 1" or so would be useful,so i am going ahead,nothing to lose,will keep, you posted

 

[velocette]

Hi
Read back through this posting and maybe this is some help.
Being disappointed in the performance of the spring loaded quadrant and short travel on my X2 mill I went totally overboard and built "Yoke" and "Air Spring " setup.
Using an an "Air spring" from the local automotive parts store Rated @ 24 kgs and 255 mm travel With external stops set 253 mm travel as standard.
With extra adjustment on the "Yoke" and resetting the stops it gives wopping 283 mm if you are interested it is posted at

http://www.homemodelenginemachinist.com/showthread.php?t=15157.

Hope the photos make it a bit clearer than I can describe

Eric