Disaster !! What do I do??

This topic has 9 replies, 6 voices, and was last updated 14 February 2012 at 21:25 by Wolfie.

Viewing 10 posts - 1 through 10 (of 10 total)

Author

Posts
11 February 2012 at 17:35 #84438
Wolfie
Participant
@wolfie
Arrgh bad afternoon. I wanted to replace the depth stop on my mill which necessitated taking the head off so I could run the new stop down the dovetail.

I took the head off in exactly the same way as I did it last time when I replaced the bearings by laying the mill on its back and winding the head off because I couldn’t lift it off the top with the mill upright. This worked fine last time but this time it didn’t.

As I took the head off, the base (with milling table) which must have been caught on something rolled sideways and clean off the bench breaking my stool and hitting a concrete floor

OK I managed to lift it back onto the bench and checked it over. Looks like it landed on one rear corner. It jolted a couple of bolts loose which I discovered by way of a tiny bit of play in the upright part. I did those up and its tight again.

Now what I want to know is how do I check it over for accuracy?? I have put a DTI into the chuck and run it up and down on the surface of the milling table and also on the rear edge. The surface seems OK but the rear edge has maybe 8 or 10 thou difference over the whole 12″. What I don’t know is how accurate it was in the first place cos I never did that before.

This thing has an adjustable head from 45° to -45° so how do I tell if that has been jolted. So far the one piece of metal I’ve milled a shoulder on which was only an inch and a half long has a 20 thou deviation. The DTI however would refute this . There also seems to be a very faint slope on the cut, but I’m not sure if that due to the fact that the scrap of brass wasn’t square in the first place.

Basically how do I check this thing over and how do I adjust it??

Bad afternoon, Leeds lost too

Edited By Wolfie on 11/02/2012 17:36:41
Advert

11 February 2012 at 17:35 #5942
Wolfie
Participant
@wolfie
11 February 2012 at 17:41 #84440
JasonB
Moderator
@jasonb
Google

“tramming a mill” will show you several ways to check your head is true to the table
11 February 2012 at 18:58 #84450
Harold Hall 1
Participant
@haroldhall1
Wolfie

Have a look here

OK. it’s mine, but it avoids me typing it all here!

Harold
11 February 2012 at 19:58 #84462
David Clark 13
Participant
@davidclark13
Hi Wolfie

The back of the table does not matter.

What matters is that you clock the vice up.

Then anything you put in the vice should be square to the table travel.

regards David
11 February 2012 at 22:14 #84475
Wolfie
Participant
@wolfie
If you make your vice square to the table then surely it should be square to the table travel. It has been so far. What I need to know is if this fall has upset that squareness.

What happens if you are not using a vice and simply clamping something to the table??

Harold I will take my laptop up to my workshop tomorrow and study your article in depth, thanks.

(Having your workshop a mile from your house is a serious pain in the bum )

Edited By Wolfie on 11/02/2012 22:17:11
12 February 2012 at 00:46 #84487
Flying Fifer
Participant
@flyingfifer
“the base (with milling table) which must have been caught on something rolled sideways and clean off the bench breaking my stool and hitting a concrete floor”

Are you really saying that your mill isnt bolted down to the bench ?? ie you`ve just plonked it down on a bench !!

Sounds as if you need to set up your mill first before you start any milling job at all. I`m quite sure Harold`s mill will be bolted down & the base levelled.

I know machines are heavy but vibration can cause movent “walking” so if you are going to continue this practice I`d suggest you buy a good pair if toe tectors!
12 February 2012 at 01:16 #84489
Gone Away
Participant
@goneaway
FF, respectfully, may I suggest you read the original post.
12 February 2012 at 17:18 #84539
Harold Hall 1
Participant
@haroldhall1
Wolfie

When you are testing the table, top and sides, you are comparing it to the dovetails on which it is moving and would be traveling in a straight line dictated by the dovetails. As the top surface shows no deviation, then the dovetails and top surface are parallel, as it should be.

However, you say that the rear edge shows a deviation of 8 to 10 thou over 12″ showing that it is not parallel with the dovetails and whilst this is very much less important than the top surface it is much more than I would like and have expected. It would be interesting to test the front edge to see if it is the same, also the T slots as the whole top may have been made out of line with the dovetails. In any case, I cannot see this to be as a result of the fall unless there is visually extensive damage which of course there isn’t.

I, when setting up items on the table will use a square off the front edge if its position is not critical. Also, others use keys on the base of their vice to locate it using the T slots. If your machine shows the error you mention on the slots and front edge also then you will have to keep this in mind if attempting to use these methods.

You mention that two screws had come loose, I do not think this would be possible in the convetional way and feel that they have been streached or the tapped holes in which they mate somewhat damaged. Taking one out at a time and checking would be a good idea.

Do bolt the machine down as FF says, or do as I do, that being to fix batterns to the bench top around the machines four edges.

Also, Toe Tectors should be standard kit when in the workshop.

Harold
14 February 2012 at 21:25 #84791
Wolfie
Participant
@wolfie
With help from people on here and from my club we have the machine back up and running. It wasn’t quite as bad as my panic had it

Many thanks to everybody who helped
Author

Posts