Lagun mill tapered gib scraping problem.

[Rafael Rak]

I'v got problem with saddle tapered gib. Knee ways all scraped with 0.01mm between dovetails. Flat ways parallel. Saddle : gib opposite side scraped to knee with great contact. Gib angle checked by two dials to make sure it's lifting up same. All seems to be fited , but as visible on pic I can still lift up saddle 0.1mm doesn't matter how strong I'm pushing gib in pocket. What can be reason ? Gib Is shimmed with 0.5mm sheet. I'v noticed that gib and shimm are staying rigid with knee but saddle moves.

 

[Richard King]

your not checking correctly. put the mag base on the top of the knee and indicator dial on the outside or left outside edge of the saddle and push push the saddle in and pull out. Here is how I showed Keith Rucker how to do it. I would shorten the indicator shaft so its closer though, less chance for error.

 

[Rafael Rak]

I'v checked left-right play also ,and there is 0.01mm- it's fine.But what with up/down play? Still cannot deal with.I'v tried to put sheets of aluminium foil in few places between saddle and gib to be sure there is no issue with angle.

 

[Richard King]

In my 50 years of rebuilding as a profession I have never seen that check made. check the side movement and forget about the up down test. the test should be done with a loose gib 0.015 mm on the tight side and it should be the same on the other end, never test it when it is tight as that will give you a false reading. try to used some precision shim stock. also be sure to cut or drill oil holes in the shim

 

[Richard King]

Beautiful paint job......tell us a little about yourself....I see your in Poland, are you a machinist or a hobbyist?

 

[Rafael Rak]

Beautiful paint job......tell us a little about yourself....I see your in Poland, are you a machinist or a hobbyist?

Thank You ,but paint job looks nice only on pics.I'm marine engineer but at home Im building machines
About the gib, I'm gonna to make new one.Old is in bad condition and also to thin because of "try to fix disaster by scraping :P "

 

[Tyrone Shoelaces]

Shimming a gib with a loose shim is never a good idea.

Regards Tyrone.

 

[Rafael Rak]

Shimming a gib with a loose shim is never a good idea.

Regards Tyrone.

Ant there You are 110% right.Even it looks stiff it's not.Only one good way is to use Turcite or make new one.I chose second way. Hope with new all will be nice and shiny .

 

[Richard King]

If the back side of the gib is good and you can buy turcite, i would epoxy it to the wear side. It would help us answer peoples questions if we knew you could scrape and knew about turcite prior. and not use aluminum shim. We don't know your skill level or what you can purchase in Poland. if you have a sign plate or a magnetic sign chuck i would grind the old gib thinner to accommodate .0.76 mm turcite and .0.127 mm of epoxy. I would not use any thinner turcte. I generally use 1.194 mm thickness turcite. a whole lot easier to do that then making a new gib. sorry for the typo's. i broke my left arm and cant use my left hand.

 

[Tyrone Shoelaces]

Sorry to hear that Rich. Get well soon but don’t rush back before you’re ready. Neither of us are 21 anymore.

Regards Tyrone

 

[Rafael Rak]

Im scraping about 2 years and 3 machines done for now.Gib has some internal stress I cannot remove. Every scrape pass geometry change.Shim is hot rolled steel.Unfortunately I have no surface grinder but i can make new one with this mill using shimmed magnetic table.No other way

Get well soon Richard.

 

[lucky7]

If the gib keeps moving, and doesn’t have turcite or similar glued to it, I’d put it in the oven for a stress relief cycle.

 

[Richard King]

Thanks. I have never had to stress relieve a gib or seen one change from internal stress. no offense but your doing things wrong it seems. you need to buy a copy of the Edward Connelly book "Machine Tool Reconditioning'' Biax in Germany sells the book.

.

 

[Richard King]

look at minute 5 where I show how to straighten a gib.