Index 40H

[Vinny]

Ok, I posted in the Latest Delivery thread that I finally got a bigger mill, but thought I'd start a thread here with some of the things I need to do to it.

I had a problem with the motor, it would spin up almost to speed then a click and it'd lose power and slow down, then repeat that, then rinse and repeat.    Tracked it down to a bad driven pulley bearing and today I pressed a new one in.  Powered it up, still doing it, but a little quieter now.

Lo and behold, the idler pulley bearings (there are two in one housing) are also bad, one is really bad.   I planned on replacing the spindle bearings anyway since I have it tore down this far so I called Locate Bearings and thankfully my order hadn't gone out yet so I was able to add the two bearings to the order.  I highly recommend this place!  Started the order on ebay, found I needed two bearings for the lower end of the spindle, emailed them, she sent me a phone number and I ordered the extra one, then today the other two.   Got 'em all in one box so no extra shipping!  YAY!!!

The motor was replaced some time back with a 110v single phase, but the one for the table is still 3 phase.  Gotta decide what I want to do there.  So far my choices seem to be 1) replace the motor, 2) get a static phase convertor, or 3) get 3 phase brought in.   #3 is out!   So I'm open to suggestions, I have a bridgeport drive but don't really want to use it for this.

A DRO is also something that I plan on.  I have the display and it'll use either rotary encoders or the glass type scales.  I also have an older Mitutoyo DRO that only does X and Y, the scales are the right size for this mill but the display is older and featureless.   I've considered either selling it or putting it on the lathe.   I'm rambling.

Here's the latest pic, I still need to do some cleaning.  This place is still a mess from moving the old one out and the new one in.   As you can see, it came with a vise, but no handle so that will be a not too distant future project. I see I need to update my signature too!

[Highpower]

(08-28-2019, 07:33 PM)Vinny Wrote: The motor was replaced some time back with a 110v single phase, but the one for the table is still 3 phase.  Gotta decide what I want to do there.  So far my choices seem to be 1) replace the motor, 2) get a static phase convertor, or 3) get 3 phase brought in.   #3 is out!   So I'm open to suggestions, I have a bridgeport drive but don't really want to use it for this.

Seeing as the manual shows 4 "standard speeds" for the table feed, I think I would go with a cheap VFD. You could still use the original motor for the table and a VFD would give you infinite choices for a feed rate as opposed to a static convertor that would not.

[Vinny]

recommendations on a cheap vfd?

[Highpower]

The Teco's used to be pretty popular when I last looked at VFD's. Of course "Cheap" will depend on the motor voltage, HP, and what you have available in the way of your available power supply situation.

[Vinny]

Think I just found one for about $55. Just saw a 16 min video on how to set it up and program it. Perfect! Thanks for the idea, hadn't even thought of using one.

[TomG]

I've used a lot of Index mills and they are solid machines. The only thing I would suggest keeping in the back of your mind is that they have wimpy drawbars and don't seem to hold R8 tooling very tightly, so larger end mills can and do walk out of the collet. Many Index mills I've seen have track marks on the table as a result. The solution is to use Weldon type holders for larger end mills, or leave yourself some extra stock on heavy cuts, just in case.

Tom

[Vinny]

This one has a B&S 9 spindle. It came with no collets, but a few holders. I have a 1.2" collet coming for things like a center finder. It does, however, have a few marks in the table from something gone wrong. It came with a jacobs chuck, various size holders, boring head, all with B&S 9 shanks, then there are some fly cutters and other things I've yet to look that closely at to see what they are. It did come with a collet holder, but I don't know what it would hold, all the holes but one are too small for a B&S 9. They're even too small for an ER-32. You can see it in the pic in the first post.

Forgot to mention (so I'm editing), my last mill had 3C collets that did the same thing. The first time I messed some t-slot nuts I was making and the second time hit the table.

[Dr Stan]

As to the type of collet held by the spindle as long as you have it torn down for new bearings this would be an opportune time to set it up in your lathe and bore it for R8 collets.  There are plenty of drawings on line of the R8 collets dimensions so you don't have to reinvent the wheel.  Wait until you have the new bearings and set up the spindle with the bearing held in a steady rest.  That will keep you from scoring the spindle OD.

You have a similar situation to my Fray mill.  I converted it to a reversible 240V single phase spindle motor from the Surplus Center and the feed motor was also 3 phase.  In my case Fray used the Bridgeport feed unit from the 1950's and I found prints for them available on line for free.  I happened to have a 110V single phase face mount motor and just made an adapter to marry it to the feed unit.  BTW, I also needed several gears for the feed unit and found spur gear blanks from Boston Gear that just needed some simple mods to fit.  A whole lot cheaper than buying the necessary gear cutters.

Among my many to do lists I plan to add two more pulleys to the spindle drive so I can slow down the spindle to some RPMs that will allow me to use larger HSS end mills.  My slowest RPM is around 500 and I want to get it down to about 200 so I can use the 4" carbide face mill.  I already have a ER32 collet adapter so I may or may not bore the spindle to accept R8 collets.

[Vinny]

Wells-Index will grind the spindle to R8, but since I have holders for all of the common sizes, I may just leave it at BS9. I ordered a BS9 1/2" collet and got notification that it was delivered ... to Mt Vernon, WA. Nowhere near me. The VFD I ordered should be here sometime this week, I already started getting the mill ready for it, but I'll also have to run a 220 line to where the mill is. I need one there anyway since the surface grinder sits there too, then I'll rewrire the main motor for 220.

[Dr Stan]

There are those who claim a surface grinder will produce better finishes if it has a 3 phase motor instead of a single phase one.  Personally I think there are more important factors than the electrical signal going to the motor.