Thread: Tramming question for the experts

HM52 mill
Where is the correct place to shim so that Y axis is in Tram?
(X I have set but Y needs doing and that means I will need to X again.)

Richard

What part of the Mill are you useing for your readings.
Have you set the Head true.
What variation are you getting in/out.

Hi eskimo,
First off, what model did you get, a HM52 or HM52B
I know it's alot of work but first you shoud check to make sure there is no paint or anything between the coulmn and the ram base also between the ram and the bolt on swivel plate for the head (12mm alen key). Mine had some which I scraped off. You will get a bit of bog cracking when you sepperate them as they only scrib the join lines into the bog after assembly.
It would be better to remove material off the other side of the column so it has full contact with the ram baes rather than adding shims.Adding shims as you know lifts one side but it leaves an air gap with no contact in between.
On mine, the ram base is ground and the column is roughly scraped so it would be better to remove it from the column.
I wont go through it all over again here, but if you read through the old posts you will see that thats the type of trouble I had with the 2 mills that I returned.
Before anything else also check the squarness of the Y axis with the column, thickness of the table at each corner and the table for warp.
If I can help with any other info, let me know as I pulled my mill down and went through it (with pictures).

Regards Dave

Pipeclay
I am wanting to square the head with the table for Y axis
at this stage I am getting .002" error.......looking from the right side of the mill the head is sloping outwards at at the top and back into mill where the cutting tool would go

Have you put a dial indicator in/on the quill and run the table back and forth under it to make sure it's not the table or the Y axis?
Dave

Dave
Mine is the same machine as the hare forbes HM52....just a different colour head...mine is yellow instead of blue


i think i need a pic with arrows pointing to ....ram, ram base etc etc

I will do a search of your old posts

The ram is the big long box behind the head. and the column is the upright post that everything attatches.
My H/F book states a maximum of 0.10 in 200mm you are half that so it is not a big concern.
Are you tightening the knee gibs when doing these tests as it make a difference.
Dave

Dave
Its all square....just had to loosen the 4 allen key bolts where head attaches to ram and then tightened and it went to less than .01mm across the table for Y and same for X....wonder why it did that?...now to do some maching to see if it stays there.

How hard is it to replace bearings in the spindle....why? well my experience with chinese bearings says they are'nt that good.... the motor bearings don't sound to good. centre pulley bearings were noisy the day I got it...have replaced these....as for motor ...well I am thinking of changing it over to a new one anyway.

On this ..can one or is it feasable to put in a 2 pole (2800 rpm) 2.2 kw motor (in lieu of 1.5 kw), with a VSD ....sonic on ebay has them really cheap...ok I know its chinese and its a contradiction to what I have and say above, but, but its cheap and if I over size (3kw) it a little, it may just last? ...else i could get one from wolfautomation. Even from my suppliers thru the business they still want too much for either a 1.5 or 2.2 VSD brand name drive.

Or should I stick with a 1.5 kw motor?

Eskimo,
Good to hear you got the alignment a bit better.
I took the whole head apart to washed and re grease the bearings as my idler pulley bearings were the same as yours on both of the machines I had.

A lot of people including me are going to the 2.2kw 3 phase motors, so it would be a good choice. The Chinese drives would be the one I would go for, and from what I have read on the internet, a lot of people have bought them and are happy with them. I will look it up a bit latter and give you a few links to their reviews.

The spindle bearings are fairly easy to get to. I didn't but new one's, I just washed the white cooking fat looking grease out of them and replaced it with good quality grease and they have been fine.

To get the quill out (from memory),

I am not sure if yours has it (my old mill didn't) but if you have a machined groove down the left hand side of the quill (extend it and have a look) to stop it rotating you need to remove the 2 screws holding the alignment pin on the left hand side.

Lock up the quill lock.

Place a block of wood on the table between the quill and table, wind the knee up until the block touches the quill to stop it dropping when it is released.

Undo the chrome cover on the left hand side of the head that covers the quill spring return. Under this there is a round cast iron piece that the spring sits in. Under the left hand side of the head their is a small screw or grub screw, undoing this will release the collar but be careful as it is tensioned to keep the quill up (wear a glove) it will want to spin round about 1 turn. The collar has a few holes around the outer edge were you can put a small screw driver or something to stop it for rotating, they are also helpful for tensioning it when you reassemble.

Undo the 3 bolts on the right hand side of the head that hold the quill handle/fine feed to the head and slide the whole lot out.

Remove the quill lock the wind the knee down to with draw the quill from the housing.Be careful as it has a bit of weight in it.

Once you have it out you will see on the top of the quill there is 1 or 2 nuts that have a metal tab under them that is bent up, just bend these down and undo the nuts.After that you need to press the quill out of its housing. I found that a soft face hammer worked and it came out without much trouble.
There is a plain bearing on top and a taper bearing like a car wheel bearing on the bottom.

I also went through the spindle pulley bearings at the front of the head as they were a bit rough sounding as well. They are not part of the spindle, the only connection is with the quill spline, that runs through the middle of it.

I hope this all makes sense as it's a lot easier to show someone than it is to right it.
Dave

thanks Dave
after I do the bearings, i willo probably have all the hassle in the world getting the head square again...you know murphys law!?

as for the motor...any benefit going to a 2 pole 2800rpm motor over a 1440 4pole

I know I will lose some torque but then again it is a bigger motor than what it has now so how much would I lose.....I am waiting on some tech data from motor rewinders on both to compare, .... at this stage motor rewinders dont know if this info is available

also ordered one of the vices you directed me to at Assett in Victoria...bugger me their freight charges were a bit rich so I checked out freight charges on the net and two co's wanted in the order of 30-35 bucks...so i rang Assett and complained that their freight was a bit over the moon and he rang back later with a charge of $30.00....a lot lot better than their online buy price for freight of $150.00 to adelaide...they came to party and good for them...glad I complained non the less

Eskimo,
I think you should be right with the head alignment as you don't have to move it to replace bearings.
Not sure on the motor as I don't know much about three phase motors so someone else may be able to comment. The one thing I would be worried about is low speed torque as I think 4 pole will be stronger than 2 pole. If it was me I would go for the 4 pole because the original motor speed is around 1400.
It might be better opening a new thread to get more responses on the motor decision.
Lucky bloke getting one of those vises, they look super nice.Good job on getting the postage down as well. I have been eying them off for a while now.
Any chance of a review with a few pictures when you get it?
Dave

No probelms Dave

As for the low torque...I did figure that out...eventually

Originally Posted by eskimo

Dave
i think i need a pic with arrows pointing to ....ram, ram base etc etc

I just had a look at a site that Big Shed put up links to, and found it has just what your looking for to be able to identify the mill parts.
Milling Machine Terminology
I had to go into my compatability settings in tools (top right of screen) of my computer to get it to work. You should be able to mouse over parts of the mill and see a screen tip.
Dave

thanks Dave

Also the Grizzly site had a much better english manual (pdf file)for the HM52 clone (from Ronmack in Perth) than the one that came with it.However the exploded views are still hand drawn...hahaha