Squaring the IH mill

[QSIMDO]

Wondering if you folks could shed some light on the squaring up procedures?

I just spent the weekend following the procedures on the IH web site and, though I'm close I don't think close enough for a machine tool plus some other issues have popped up.

I'll describe the issues first and bear in mind this will never be a CNC machine so if my expectations are too much, tell me I'm nuts.

While running the head down the column it will catch/release ad infinitum, sometimes with a high enough frequency to create a low rumble and other times it catches and drops about a .25". I have the gib pretty darn tight so does it need the head slide mod shown on the web site ?

Tramming the head shows .005" front to back. I put a jack under the front of the head and can get that much out, but the column base and the head swivel bolts are tight as tree bark. Gibs again?

I wanted to get some hours on the machine before I did all the lapping & such so perhaps things will settle down once that's done?

I bought the IH because it was easier to move than a knee mill but after welding and grinding a stand and then hovering around that machine for 2 days I'm feeling I should have got the Bridgeport and dragged it around the house by its heels!

Well....let me make something with it first, then we'll see.

TIA!

[Cruiser]

Hey there dude, well, i'd have to say ya shoulda woulda coulda ! send the z saddle back to aaron for the modification while you lap in the rest of it and when the saddle comes back lap it too. then with moderate gib tightening you should have it. when adjusting the gibs, forget about the gib locks for a while and make sure that they are backed off and stay that way. only use the gib locks when really needed and don't forget to back them off, they will put dimples in the back of the gib and they will cause a localized wear pattern and you don't want to start off with any interference in the initial setup. I am going through the same process with a full cnc version 3 of which is the very same v-3 pic'd on aaron's website, He shot the pics and boxed it and now it sits in my shop ! and i will say it is a nice piece of work. you have a solid machine, the whole idea is to take over where the chinese left off and make of it something that will work for you, and it will do that for sure. as for the head tramming in too within .005 you can get a cheap feeler gauge set and put one in underside to shim the head to level, if it still be off then change shim. have fun, and make some chips. I should be making chips real soon too !

[ViperTX]

Welcome QSIMDO.....I would agree with you on the Bridgeport.

[QSIMDO]

And I do this every time too Viper! I should just make a decision and then do the opposite! Just like George did that day in the restaurant.
BUT, it's time to "run what I brung" so I must forge on.

Cruiser's right. I'll just put off burying my shop in chips and do it correctly.

Here, let's see if I can post a pic;

[QSIMDO]

Jeez, for a Canon A95 that pic really sucks, no?
Oh well.

Now, you see the 4 hockey pucks for isolators?

Bought the 4 of them on the 4th of July and the clerk didn't bat an eye. What have we come to?

[BobWarfield]

Originally Posted by QSIMDO Now, you see the 4 hockey pucks for isolators? Bought the 4 of them on the 4th of July and the clerk didn't bat an eye. What have we come to?

Heck, I bought a box of 30 on eBay for $7. No idea what I'll use them for. People do bat an eye when they see the box sitting there in my shop. I've been tempted to see how well they cut on the mill and lathe, but haven't gotten to it yet.

I have not see the catch/release problem on any of my axes. Make sure everything is properly lubricated with way lube, or at least chain saw oil if you are in a real rush. Then I'd carefully check how you are adjusting those gibs. My machine ran smoothly on all axes out of the box. What few problems I've seen have been with the quill, as I mentioned over in the other post.

You might also ring up Aaron and see what he suggests. Better catch him before he heads off on vaca. I can't imagine his Z-Axis mod will fix the stick-slip problem you describe, however. It almost sounds to me like your gibs may be a touch too loose.

Best,

BW

[Cruiser]

I couldn't help but show QSIMDO what his can evolve into ! this is an early shot and i've done plenty since but still needs more, need the plexy to fill the openings and form doors with. OH Yea who needs a fancy enclosure anyway...i'll just make another plexy shield and still be able to easily access or watch the goings on !

[CNCPlastic]

Originally Posted by QSIMDO I have the gib pretty darn tight so does it need the head slide mod shown on the web site ?

The Z axis slide mod is mandatory in my opinion. Aaron designed that mod after I measured .020 slop in my Z. Note I have a Lathemaster mill with an early IH cnc kit not the IH brand mill but the same company manufactures both mills last I heard.

As far as sticking, sounds like the gibs are too tight and/or it needs to be lapped. That head is so heavy it will pitch forward which doesnt help. Its heavy enough that it should be counter weighted in my opinion. I counter weighted mine with 180 pounds. The head is still downward heavy about 20-40 pounds but that took a lot of stress off the axis.

Also my mill required extensive lapping and I never was able to remove all the tight spots. Y and Z were tight at all the cross ribbing areas. Z was tight at the top and bottom, Y at the front and rear. That said lapping made a huge improvement.

At this point I have outgrown my IH mill and I'm mulling over quotes on a Hurco VM1.

[Capteod]

I am just finishing the CNC Conversion of my IH Mill. I have counterweighted the Z axis with just over 225 Lbs and it does not stick. The reason most of you will have the problem with the head tilting, is that the lifting point is not at the Center of gravity of the head stock. Instead of mounting the pulleys as close to the column as possible, I cantalerered pulleys so the lifting force is centered on the Head of the and now the Z axis is not cocking as it is raised ir lowered.

[QSIMDO]

Certainly makes you wonder why the design hasn't been improved.

That is a tremendous amount of cantilevered weight to be bearing only on those dovetails. Should be some sort of rolling element design I'd imagine.

One of you crafty devils should design something!

[miljnor]

Sweet enclosure Cruiser!

I have always like these IH mills although I must warn you might have incurred the wrath of the anti-lapping police! I am sure you will hear from one of them soon!

shhhhhhh. Speak very quietly or they will come and get you...

[Cruiser]

Hey all, I've been studying the "z" axis and have a very strong solution in mind, as soon as i have the cash i'm going to build it for my machine. It will not be counterbalance or gas strut, and it will take care of all the slop on the dove's because it will replace the doves without cutting them off and it will add plenty more to collumn, but i can't start till after taxes tho due to funds. the material will be durabar and will entail a new z saddle to hook it all together. If it works out affordable i may make it available but i don't expect it to be cheap as there will be extensive machining involved.
I took a really heavy cut with my mill and a 3/4 c-bide end mill in some tool steel to see what it'd take and it danced pretty good, the whole head bucked up and down and the table did a fair dance too, but man the chips did fly ! I can't wait to do the same test after the modification. the rest of the machine tho is awsome and didn't care one bit bout the dancin goin on.
oh and Aaron has the new model machines in now and it looks pretty good, still dovetail z but a better mounting to the saddle, wish i could get one !
Added the pic, note that this is the weekest cutting method possible on this mill as it will pick-up the whole head, but i had to know ! It danced, and it pulled chips, and i can't wait to do mod !