Thanks: 0
Needs Pictures: 0
Picture(s) thanks: 0
Results 16 to 30 of 30
-
10th Apr 2012, 12:43 PM #16Dave J Guest
Heavier oil might do the trick, you would have to give it a try.
With the quill drop I have heard a few people talk about this. On my mill (HM52) there is a clock spring which is adjustable for the rack gear. I have mine set up to raise the quill if I let go of the handle. This way the quill is always pushing back on the rack and doesn't drop at all.
Without this adjusted I could see where the quill would drop, so if you have the spring, give it an adjustment. Mine has 2 holes in the out case after taking the chrome cover off and has a screw under the head which locks it in place. I place a small allen key in one of the holes while undoning the screw and then rotate it anti clockwise for mine to put more tension on it.
Dave
-
10th Apr 2012, 01:15 PM #17Senior Member
- Join Date
- Feb 2011
- Location
- Mornington Peninsula
- Posts
- 183
Thanks Dave
Yes I have played with the tension spring and it works where the rack and pinion is working more or less ok.
However. This may not be the best explanation but there will always be a point where the whole mechanism plays catch up and drops over 1mm. Nothing can really stop that. It's almost like a tipping point.
My pinion seems to force the quill across to some extent so there is a limit of how much tension would allow the quill to return unaided.
Of course you don't need to use all the travel but the tension is such that it works over a partial range. If the spring was tensioned enough to return at full extension it would require more preload than I could wind on.
I messed around with preload using a big lump of high density foam and found that there was still parts of the travel that no amount of preload would improve. You would still get a "step change".
Cheers
Justin
-
10th Apr 2012, 01:36 PM #18Dave J Guest
Interesting as I don't have that problem at all, I posted my setup over in the other thread.
Dave
-
10th Apr 2012, 01:52 PM #19Philomath in training
- Join Date
- Oct 2011
- Location
- Norwood-ish, Adelaide
- Age
- 59
- Posts
- 6,541
Just a thought - that clunk - have you checked the fit of the keys in shafts to handles, pinions etc? It sounds like back lash of some sort, where when a shaft gets to a certain rotational point gravity means that something is pulled forward rather than pushed back. (I would hope that keys are being used rather than grub screws)
Another cause of the jump could be a missing tooth on the pinion or rack, but that would be far more than a mm.
Michael
-
10th Apr 2012, 02:44 PM #20Dave J Guest
I thought I would post it here as well, since it's to do with this mill and not cutters.
On my mill, on the opposite side of the head to the fine down feed the shaft from gear comes through the head and there is a clock spring on the end of it.
Do your mills have something like this, if not this is the problem with the quill dropping.
Dave
-
10th Apr 2012, 02:52 PM #21Dave J Guest
After looking at the grizzly parts manual below, I see it is the same set up as mine with the clock spring.
http://cdn0.grizzly.com/partslists/g0519_pl.pdf
I also checked the slop between the rack and gear and mine has about 0.5mm movement up and down at the quill. My quill is heavy enough to fall on it's own, by the sound of it your quills are getting hung up on something. I also grease my quill to help with some of the play, and even with that it drops down no problem.
For mating the gear to the rack better, I do have pictures etc of one guys method where he bored the head casting to take bushes, and then he bored the bushes off set to give adjustment of the mesh of the gear. This will only work if the gear will mesh with the rack without and play, so you would have to do a bench test to see what it's like.
The only other thing I can think of is to place a spring on the quill to help hold it up. This would stop it dropping down.
Dave
-
10th Apr 2012, 10:34 PM #22Senior Member
- Join Date
- Sep 2007
- Location
- Newcastle NSW
- Age
- 77
- Posts
- 155
Hello Jarh73,
I have explained my solution to this problem before but at the risk of boring everyone here I go again.
On my mill (Zay7045FG/2) the play is between the Quill rack and pinion, as on other machines. I found that when I released the Quill clamp, the two cast iron slugs which pressed against the Quill did not release immediately, but when I started to lower the Quill the clamp released which caused the Quill to drop and produce the "clunk" sound. I turned the ends of the two "slugs down and pressed brass end pieces onto them. I now keep the Quill clamp nipped up slightly and the brass end pieces do not grab onto the Quill and do not score the Quill surface. I also replaced the grub screw which locates in the slot down the side of the Quill, with a bolt with a phosphor-bronze end piece, and I keep this tightened slightly also. I don't have any problems with the quill dropping now . I have fitted a vertical digital scale to the Quill which I think is necessary to show exactly how far the Quill has moved .
Russell
-
12th Apr 2012, 08:16 PM #23Senior Member
- Join Date
- Feb 2011
- Location
- Mornington Peninsula
- Posts
- 183
-
2nd Oct 2016, 08:26 PM #24New Member
- Join Date
- Dec 2008
- Location
- NSW
- Posts
- 7
Hello
I just started a new thread about this machine and now I found this.
Does anyone know how to get the top open? I want to clean it out and replace the seals.
Motor is off, 6 top screws are out and top can lift 25mm.
No more.
What am I missing?
Regards
Bernt
-
10th Oct 2018, 04:27 PM #25New Member
- Join Date
- Oct 2018
- Location
- Hazelbrook, NSW, Australia
- Posts
- 1
I have just become a member of Metalwork Forums. Spent 20years as Fitter/Machinist, and other pursuits, before retiring. In relation to the HM-46 Mill Drill, the Men's Shed I belong to purchased a one with digital readout, coolant pump etc. My experience with the machine was that the difference between the graduations on the find feed dial and the actual amount removed is .020 inch with the lock lever on, while the digital depth reading would change .002 inch once the lock lever was put on.
The machine would also chatter under a heavy cut. On investigation on a few forums, the problems seemed to be no vibration absorbers fitted, and the HM-46 does not have the option of an R8 taper, only a Morse taper. Morse taper okay for drilling, but R8 taper is better for milling. A company from Melbourne sells a Metex DM45 with an R8 taper, and from what I have read, everyone that has purchased a DM45 is very happy, and not reporting the problems of the HM-46.
-
10th Oct 2018, 06:25 PM #26Golden Member
- Join Date
- Aug 2012
- Location
- Australia
- Posts
- 645
The castings are the same between the DM45 and the HM46. It’s just the brand name that’s different. The reason you’re not finding bad reviews is likely down to the fact that H&F have sold a heap of them and all the rest sell a much smaller volume.
I happen to own an R8 45 and have plenty of complaints. If used within their limitations they can serve a purpose.
-
10th Oct 2018, 07:15 PM #27Most Valued Member
- Join Date
- Jun 2011
- Location
- Australia east coast
- Age
- 71
- Posts
- 2,713
I seem to recall you had about the same contact area on the slides on a brand new machine as I did on a 70+ year old Monarch lathe.... scraping is such fun
They make really good heavy duty drill presses with a built-in X-Y table. As milling machines, not so great. We had one at work, bought it to keep the electronics techs away from the good machines.
PDW
-
10th Oct 2018, 07:27 PM #28Diamond Member
- Join Date
- Sep 2006
- Location
- Mallacoota,VIC,Australia
- Age
- 53
- Posts
- 1,010
I have posted this in the past, but I haven't been back on the forum in a long time. Here's a link that should help http://www.graetech.com/index_files/Page878.htm and the PDF version which I got from somewhere that I can't find now anyway I just up loaded it here http://www.filedropper.com/rf-45millheadrebuild
I hope it helps.
All The Best steran50 Stewart
The shortest way to do many things is to do only one thing at once.
-
11th Oct 2018, 07:36 AM #29New Member
- Join Date
- Dec 2008
- Location
- NSW
- Posts
- 7
Still, for the price, it is a reasonable machine. Since posting about the problems with the oil leaks and non concentric grooves for O-rings on the shafts, I have had no issues with the machine.
Ok, I do not use it a lot but I have machined several large gears and other stuff on it without issues.
The Z axis is not the best and needs to be lock lever needs to partially lock to create friction so avoid uncontrolled downward jumps when turning the handle.
Regards
Bernt
-
23rd Oct 2018, 01:29 AM #30New Member
- Join Date
- Jan 2015
- Location
- Newcastle
- Posts
- 5
Hi I only recently acquired my HM46, very happy with it, the clunking noise, I think come from the quill return spring, I heard that noise straight off from using my machine, when using the down feed handle
sorry read further on all the same track
Similar Threads
-
Problem With a Hafco HM-46 Mill/Drill.
By Jarh73 in forum METALWORK GENERALReplies: 28Last Post: 23rd Jul 2012, 11:51 AM -
hafco mill collant setup help
By welder in forum METALWORK GENERALReplies: 4Last Post: 20th Feb 2010, 09:55 PM