Here is a list of all the postings Wolfie has made in our forums. Click on a thread name to jump to the thread.
|Thread: Rough Milling|
No the head wasn't on the body when it fell. Yesterday I dismantled the bottom half completely, cleaned all the slides etc put in new grubs for the gibs etc (why is chinese steel so crap?).
It was my club meeting last night and I took the newly skimmed block and my endmills. The general consensus was that the finish was as good as I could expect from a cheap mill and that the endmills weren't good. I'm not convinced though.
Harold it is 230M07 as required
Heres the pics, this is what set me off worrying about it again
I have since skimmed this again with an endmill that hasn't been used before. It was quite small though and took ages. Its a much better finish but is still showing a few circular lines.
This is what it looks like after much sanding, you can still see circles in the metal grrrr
This is what I meant by 'notches' in the mill ends, a bit blurry but you can make them out in the circles on the endmill on the right. It can't be blunt as its never been used, my collet set doesn't quite go that big. The endmill on the left is the one guilty of the messy milling this time. Note it only has one notch in it not all 4??
I'll get some photos tomorrow
OK so let me summarise.
The possible causes are as follows...
The mill head is out either left or right. Its possible, but folks will remember that this is the machine whose lower half dropped off a bench onto a concrete floor and it was substantially checked over at the time by a member of my SME.
The mill head is out back to front. Possible. I did check this especially as I noticed one of the gib strip grub screws was loose. This was also checked at the time of the accident.
The slides are out/loose. Also possible after the accident, these were only checked as far as putting a clock into the chuck and running the mill table back and forth. Was OK. How would I check this more?
The cutters are blunt. Also possible. I bought a set from Clarke for what I thought was an expensive £70 some. This was however 3-16mm both endmills and slot mills so maybe cheaper than I thought. I do note that they seem to have a curious semicircular nick in the end of the blade. Some have it on all 4 and others on only one or two. I get the problem with every cutter though so either they are all blunt.....
And for that matter I know very little about them, what constitutes a blunt endmill?? Especially in the hands of a novice.
There is no doubt in my mind that this mill hasn't cut as well since the bottom half (base, slides and upright) acidentally rolled off my workbench when I was trying to replace the depth stop of all things. It dropped onto a concrete floor and I was somewhat surprised that I hadn't at least bent the leadscrews or something! It has been thoroughly checked for accuracy since then and appears OK but as I said theres no doubt that its not cutting as well as it did before that
I'm getting to the point where I'd pay to have it checked out by an expert but as they all appear to be down south I don't know of anybody remotely locally. Grrr.
I'm in the position of having a lathe thats probably older than I am which is superb (and British) and a mill thats barely 6 months old which is giving me problems. Lack of space and cash is my restriction before anyone offers me a Bridgeport
I am getting some really poor finishes with my milling machine. What are the possible causes??
Seems to differ by direction, ie across or back and front traverse.
Its almost knurled in some cases, I can drag a fingernail over it and feel the cuts. Looks a bit like a ploughed field on places too.
I'll get some pics tomorrow.
|Thread: Setting odd leg calipers|
Whats an edge finder?
So far to get a line to cut or mill to I have simply set my digital vernier to a few thou over and scribed it with that.
Clearly that is never going to be exact so I need a set of odd leg calipers. Now these appear to be like any other caliper ie sprung at the top. So theres always going to be a small amount of give.Whats the correct and accurate way to set them? If you are just touching the pins of your vernier or micrometer it seems to me that theres still room for error as you generally have to account for a bit of 'springiness' when you nudge the calipers together.
Edited By Wolfie on 27/07/2012 11:42:05
|Thread: Lathe problem|
After some use it started doing it again. Inspection showed more of that shiny stuff on the pulley. Its coming off the new belt I think. The pulleys are definitely in line
Anyway problem sorted, belt sprayed with spray glue!
|Thread: Drilling on a taper|
Thanks all it worked a treat.
Borrowed a V block, put taper in and mounted it in milling vice. Started hole with centredrill.
|Thread: Grinding lathe tools|
Excellent and informative discussion, thanks chaps.
|Thread: Drilling on a taper|
"One way might be to put the taper in a vee block mounted at an angle"
Thats the idea I was looking for! Ta
I didn't know there was another way of drilling it
Well presenting the taper to the drill kinda assumes that I want to drill into it at the normal 90º.
Its mild steel and 6mm
I have some bar which has been turned to a taper at one end. I now need to drill into this. How do I hold the work to present the taper to the drill?
|Thread: Lathe problem|
I've been for another play this aft.
Robert you are right, the threaded bar with a nut on to the right is the tensioner, the handle is just to change the belts. The pulleys are in line.
In the end I took the pulley off and found the larger pulley coated with some kind of slippery shiny stuff. Cleared that off and tensioned it up again and its a lot better. I'm gonna get some of that spray sticky stuff too and spray that on the back of the belt.
Back in business!
More pics here...
Its a flat belt, will go up and videocam it later today (my workshop isn't at my house)
Found a picture on the net, this show the belt in the slow range position, the pulley for the high range is to the right of the belt behind the tensioning handle.
Edited By Wolfie on 20/07/2012 07:23:53
Edited By Wolfie on 20/07/2012 07:24:33
I don't recall the old belt doing it but it snapped shortly after I bought the lathe and I didn't keep it.
No its a new belt. I can get some pics tomorrow.
Please help. I have a silly little problem that is causing me grief way beyond what it should be doing.
My Smart and Brown has a belt drive and high and low speed ranges which are controlled by shifting the belt from a small pulley to a big pulley at the bottom and big to small at the top.
So low speeds have the belt on the small pulley at the bottom and large at the top. Now I want to speed things up a bit so I have changed to the high speed range. The problem is that the belt won't stay on the pulley. It slips off every time I start the lathe.
The bottom pulleys are one piece with the smaller one furthest out on the shaft. This has a small lip on it so the belt can't slide off but the larger pulley has no such lip and when I start the lathe the sideways jerk of the belt pulls it off 9 times out of 10. I have tightened up the tension to the point where I can barely push the lever back up but it makes no difference.
A colleague seemed to think I could tilt the motor/gearbox assemly but if I can I can't work out how to. Most of it is out of reach of the hatch in the case and I can't get behind it as its up against a wall (and weighs 3/4 of a ton).
Its driving me nuts how do I sort this out.
|Thread: Drilling a long way through steel.|
Thanks all, mission accomplished with centre drill, 4mm and 8mm in turn!
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