My new Chinese mill-drill

Skierdude

David P
H-M Supporter - Silver Member
Joined
May 24, 2017
Messages
78
Last year I bought a new Taiwanese lathe here in New Zealand from Machineryhouse (Hare and Forbes) and since then I’ve been looking for a mill. This is a new hobby so I’m looking for a basic machine to learn some skills.
Space constraints means a turret mill isn’t suitable so my only option is a bench mill. I watched the second hand market for a year or so but nothing interesting came on sale. There are not a lot of mills on the second hand market here in New Zealand, so when Machineryhouse had their June sale I couldn’t resist a good price on an entry level mill drill. I got the HM-46 which is a Chinese built 1 1/2 HP unit sold generally under the model ID ZX7045. I was rather apprehensive about buying what is often described as a POS but a good look at the machine before purchase convinced me it is a value for money start to milling. I’ve read many posts and seen a number of videos of all sorts problems with these cheap Chinese mill drill units so my expectations were in line with the cheap price.
I picked up the machine a few weeks ago and here’s where I’m up to so far:
Unit was well crated. The rust protection coating of metal surfaces was rather minimal but there was no rust on any surfaces.
The sheet metal stand is quite lightweight but nevertheless strong enough for the task. My concrete floor is a little uneven and I didn’t want to have uneven packing under the stand so I fabricated an adjustable base - the side benefit is the mill is now 75mm higher so that suits me much better.
34DE7500-144D-42A3-B540-6104ED9D78B8.jpeg


So the mill is now mounted on its stand and reasonably level with a slight slope towards the coolant drain.
I’ll let it settle for a couple of weeks and then check the level and tram the mill and vice.
So what to do while I wait. With all the previous comments on Chinese mill drills I wanted to make sure there was grease in the bearing, oil in the headstock, no casting sand anywhere or metal chips etc.
Bondo type filler is used on the castings to fill defects and make the unit look smooth and sleek. I’m not against fillers, it does make a smoother surface so it’s easier to keep clean but a little paitence and care would give a better result. Filler has been added over poorly prepared surfaces so chips off easily. The unit was spray painted after assembly and again not enough care in masking areas so there is overspray in places it shouldn’t be - on ways, gibs etc.
So the table was removed so I could clean up and repaint properly. The castings look to be machined and ground quite well but the finish is rubbish. It looks like the casting was cleaned up with an coarse wheel on an angle grinder. Half an hour with a die grinder had the table casting tidied up.
The lead screw bearings were well greased but got a clean and new grease- just to satisfy my perfectionist nature.
The surfaces on the ways are not great and will get a scraping in the future.
Other observations so far:
The mill seems to be a solid unit
Poor finishing but looks like it will be quite functional
Electric motor sounds to be good running unit but time will tell.
Electric switch feel fragile so will get replaced sometime soon.

So having uncovered what I found so far am I happy with my purchase?
Yes I am. It’s probably better than I was expecting.
More details to come when I break out the DTI - hope there are not too many surprises.
 
I hope you won't you be surprised when you break out the DTI.

I have the HM47 and the table raises 0.02mm in the Y as it comes forward and the X and Y are not square. The tram changes depending on head height and how you lock the Z gib also changes the tram. I put the X and Y gibs on the surface plate and they rocked like Elvis.

I have scraped the Y slightly as there was 0.30mm play in the Y ways. At least the table does not rock back and forth now. Most of this was the gib.

BTW I also have a a Hafco AL336 and it is worse than the HM47. Both units are less than 2 years old and not done a lot of work.

ON the good side spindle runout is less than 0.005mm
 
Nice stand. I used some Lev-La bases from Comac.
I have a HM46 as well going on 5 years old and for the price I reckon it is very good value. there was the thick creosote in the gearbox which is why a cleanout is in order. The bearings are not the best quality 6007-2RS and 6202-RS so readily available and cheap if replacement is needed,(I popped the seals, washed and repacked with some aerospace Morey's fortified red stuff),found zero swarf, sand or anything else. Only problem I had was L,M & H shift lever was sticky. This was due to the keyway for the gear cluster being cut with a heavy feed which threw burrs on the edges of the detent grooves. 10 minutes with a riffler and a lap with toothpaste and now silky smooth. Max runout on table is 0.02mm and about the same as that on Z axis. There is 0.2mm backlash on X & Y screws. As said for the money good value and unless you pay a LOT more you will have to fettle which means you can transition it into something better.
A tip if you want to remove the lid. The dowels are tapped M6x1 so can be jacked up 20mm before removing the 6 hold down bolts, this makes getting the lid off a lot easier. Make a screw in punch to knock them down slightly to aline when refitting and drive home before final tighten.

Epoxy Granite and some scraping is in the future.
 
Thanks for the comments warrjon. This weekend will be measuring time. I won’t be too surprised to see some tolerance issues, I guess that’s part of the challenge with this level of machine. There has been some attempt to get the slideways surfaced but it looks a bit crude and until I get a surface plate I won’t mess with it right now.
I’ll post an update once I get some measurements.
I bought an AL-960B lathe last year. These are made in Taiwan and the build quality is so much better than the HF46.
 
Nice stand. I used some Lev-La bases from Comac.
I have a HM46 as well going on 5 years old and for the price I reckon it is very good value. there was the thick creosote in the gearbox which is why a cleanout is in order. The bearings are not the best quality 6007-2RS and 6202-RS so readily available and cheap if replacement is needed,(I popped the seals, washed and repacked with some aerospace Morey's fortified red stuff),found zero swarf, sand or anything else. Only problem I had was L,M & H shift lever was sticky. This was due to the keyway for the gear cluster being cut with a heavy feed which threw burrs on the edges of the detent grooves. 10 minutes with a riffler and a lap with toothpaste and now silky smooth. Max runout on table is 0.02mm and about the same as that on Z axis. There is 0.2mm backlash on X & Y screws. As said for the money good value and unless you pay a LOT more you will have to fettle which means you can transition it into something better.
A tip if you want to remove the lid. The dowels are tapped M6x1 so can be jacked up 20mm before removing the 6 hold down bolts, this makes getting the lid off a lot easier. Make a screw in punch to knock them down slightly to aline when refitting and drive home before final tighten.

Epoxy Granite and some scraping is in the future.
Thanks NortonDommi. When I made the stand I needed 3mm recess in the support plates to locate the adjustment screw. My idea was to use a 16mm end mill but with no table on the mill I decided to find out what it was really like to use a drill press as a mill. All those experts are right - it did work okay for what I was doing but forget any idea of actually milling! Thanks for the tips on removing the lid, I’ll do that and clean out the head.
Did you have any trouble with the spindle not being aligned with the y axis - I.e. nodding forward or backward ?
 
Thanks for the comments warrjon. This weekend will be measuring time. I won’t be too surprised to see some tolerance issues, I guess that’s part of the challenge with this level of machine. There has been some attempt to get the slideways surfaced but it looks a bit crude and until I get a surface plate I won’t mess with it right now.
I’ll post an update once I get some measurements.
I bought an AL-960B lathe last year. These are made in Taiwan and the build quality is so much better than the HF46.

Yes a granite surface plate is a great tool, I use mine regularly, almost once a week.

I think most of the issues with the HM47 are the gibs. I sanded the gibs flat on the surface plate then shimmed them. Made a huge difference in surface finish on aluminium.
 
"Did you have any trouble with the spindle not being aligned with the y axis - I.e. nodding forward or backward ?"

For once, just once in my life I seem to have lucked out and all is good. Model Engineers Workshop had a great article on checking mill/drill alignment. I'll see if I can dig it out. Very simple and accurate.
 
Decent looking little dovetail mill popped up on Trademe today. Horizontal capabilities and high speed turret head.
 
"Did you have any trouble with the spindle not being aligned with the y axis - I.e. nodding forward or backward ?"

For once, just once in my life I seem to have lucked out and all is good. Model Engineers Workshop had a great article on checking mill/drill alignment. I'll see if I can dig it out. Very simple and accurate.


Mine does. Tram in both planes changes with the height of the head and how you lock the Z gib. I micro tram by tightening the lower gib lock until the tool mark in the work piece looks right.
 
Back
Top