Sieg SX2PG Mill

[Michael GilliganParticipant @michaelgilligan61133]

Just a quick question from an innocent observer …

Aside from ‘cosmetics’ and perhaps ‘manufacturing convenience’ is there any good reason why these mills use four pads to fix column to base ?

Three could be made kinematically stable

 

MichaelG.

[JasonBModerator @jasonb]

Would possibly increase the O/A footprint of the machine if the third fixing needed a flange at the back of the column. So your “small benchtop” mill would need a bigger bench but it would stop any wobble.

[duncan webster 1Participant @duncanwebster1]

Setting up to machine the pads parallel/square to the dovetail will take a bit of time, and so will be expensive even if you can find someone to take it on

I’d stick with shims, I had to shim my Naerok, didn’t take long after which it never needed touching again.

Chap I know has one of this type of mill, not sure which size. If he gets the tram right with the head at the bottom, it is out at the top. I suspect the vertical volumn is not all that rigid, especially when it has to support the cantilever load of the heavy geared head,  which is why there have been articles on how to stiffen it

[Robert Atkinson 2Participant @robertatkinson2]

I’m late to this thread, but have a thought on the machining of the pads on the base.
How about setting up a grinder (die, dremel or even an angle) on the table with the column removed and using it to “surface grind” the pads?
Height adjustment will depending on what you have available. Ideally a vertical slide, but a tilt table or just shims would work.

Robert.

[Neil AParticipant @neila]

Seeing the reply from Robert has just reminded me of one of the modifications that was done on mikes workshop web site. He used the column mounted backwards onto the table to take a skim over the mounting pads on the base to true them up. Might be worth a thought.

https://mikesworkshop.weebly.com/mill-fixed-column1.html

Neil

[Robert Atkinson 2Participant @robertatkinson2]

That’s another approach to achive a similar result. A lot depends on equipment to hand.

Robert.

[duncan webster 1Participant @duncanwebster1]

What a good idea.

[Martin Johnson 1Participant @martinjohnson1]

I admit to being “old school” but I would attach my magnetic dial gauge onto the back of a small surface plate or angle plate or similar.  Then take a measure to the 4 pads by sliding the surface plate on the mill table.  That gets you a knowledge of how good or bad the pads are.  Being me, I would then st to with files and scraper.  The backward milling approach sounds good, but would still need scraping up to finish.  Taking Jasons comment on squareness of column to it’s feet it would be good to scrape to get a true reading on the Z axis to a cylindrical square on the table.

Martin

[Author]

Posts