Gear Head Milling Machine - enough speeds?

[Ben17484]

Bid difference between a gear box lathe and a gear head mill going WHAAAAAAAAAAA at 90+ decibels at full speed. Also 6 speeds is not enough and a top speed of 1600 is on the low side even for a 6 speed gear head mill. They are great drill and tap machines. Decent for steel, stainless. Just not fast enough to be good mills for aluminum imo. You can machine it but it's going to be quite slow.

Best mill in this category available today imo is the PM 940V. Extended Y travel, 5000 rpm spindle for starters. When you are considering Y travel also factor in vise positioning, column interference and whether you can even use the entire smaller Y travel most other mills offer.

Good info. Thanks.

I don’t think they have the equivalent of the PM 940V in the UK. If they do, it’s more than likely above my price range.

 

[Ben17484]

completely off topic but as your local to me or at least in the same county where do you source your metal etc

I get mine from eBay.

I found a good deal on a bunch of square, round and bar stock a while ago and won’t be needing to buy any more for quite a while.

If there’s anything in particular you’re after PM me, I may have some spares.

 

[cooper1203]

I get mine from eBay.

I found a good deal on a bunch of square, round and bar stock a while ago and won’t be needing to buy any more for quite a while.

If there’s anything in particular you’re after PM me, I may have some spares.

thanks for the offer i shall bare that in mind.

I am a complete novice and still in the process of getting the lathe back together now most of the components have been debodged.

 

[SouthernChap]

So I think the GH Universal is either one of the RF-45 clones or possibly even an actual Rong Fu RF-45. Mind you, even if it's the latter, it could still be made in China as Rong Fu did move some of their production from Taiwan to China.

As to the speeds, the top speed of 1600 does seem a bit limiting for using smaller dia. cutters or drills.

For another £350, you could get the VMC. I don't know if it's a good mill but it does have 9 speeds up to 2100 RPM and it has the stand included and it's about the same footprint as the GH Universal, oh and it's heavier too.

Warco VMC Turret Mill - High Quality Metal Milling Machine

Highly accurate, low cost vertical milling machine, the VMC features outstanding precision as standard. Optional power feeds and DRO

www.warco.co.uk

 

[SouthernChap]

thanks for the offer i shall bare that in mind.

I am a complete novice and still in the process of getting the lathe back together now most of the components have been debodged.

eBay's good but here's a couple of suppliers I've used and liked; they seem to be fairly well regarded in the model engineering world, too:

Aluminium, Brass, Copper, Bronze & Steel online metal supplier, small quantity metal supplier, Noggin End Metals, Stoke-on-Trent

Noggin End Metals Homepage, Model Engineering, model engineering supplies, Model Engineering Materials, Aluminium Brass Bronze colphos colsibro Copper Stainless Steel Nylon Acetal PTFE PVC Peek Graphite

www.nogginend.com

Home - College Engineering Supply

www.collegeengineering.co.uk

(college engineering's site can be a bit slow loading at first)

 

[markba633csi]

If you are thinking of going to a VFD remember they only work with 3-phase motors

 

[RaisedByWolves]

Sheave head machines have 6 or 8 speeds, so you're gaining some convenience by being able to switch with a lever. If you've ever had to jockey sheaves, that's a lot of relief. Vario heads have an advantage because you can dial away chatter from cutter resonance, sometimes the "right" speed for a setup is 50 RPM to one side or the other. The world made due on sheave heads for a very long time, though, so the steps aren't a show stopper by any stretch. What you can do is put a 3-phase VFD or a variable DC motor as a retrofit on that mill at any point in the future.

The retrofit would be my suggestion.

I put one of custom crafters motor/controller on my mini mill and it’s a really sweet setup.

I can basically go from 10rpm to 5k if I wanted. Not sure the bearings would be happy at 5k, but it’s there.

 

[Ben17484]

Sheave head machines have 6 or 8 speeds, so you're gaining some convenience by being able to switch with a lever. If you've ever had to jockey sheaves, that's a lot of relief. Vario heads have an advantage because you can dial away chatter from cutter resonance, sometimes the "right" speed for a setup is 50 RPM to one side or the other. The world made due on sheave heads for a very long time, though, so the steps aren't a show stopper by any stretch. What you can do is put a 3-phase VFD or a variable DC motor as a retrofit on that mill at any point in the future.

I’m leaning towards buying the machine and In the future swapping in a DC motor.

This is 320kg vs 220kg of the my other option (the Warco WM18).

I would guess that extra 100kg would have a positive impact on the cuts it can make.


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[pontiac428]

The DC motor would be the winner for torque, they don't have the low RPM falloff that you get from feeding a chopped AC signal to a phased motor.

I'm not sure, but I think the RF-45 and other gear heads in that range have polymer gears for quieter running. I ran a Chevy L6 motor for a quarter million miles on the original nylon timing gear on the cam, so I trust the right plastics. Just something to keep in mind.

Mass is your friend with machinery, even if it's not structural mass. Inertia helps lower and damp resonant frequencies and resists deflection for smoother finish. Mass in the head is particularly important, it takes a lot more to push the tool upward and out of the cut, so weight is your friend.

 

[Ben17484]

The DC motor would be the winner for torque, they don't have the low RPM falloff that you get from feeding a chopped AC signal to a phased motor.

I'm not sure, but I think the RF-45 and other gear heads in that range have polymer gears for quieter running. I ran a Chevy L6 motor for a quarter million miles on the original nylon timing gear on the cam, so I trust the right plastics. Just something to keep in mind.

Mass is your friend with machinery, even if it's not structural mass. Inertia helps lower and damp resonant frequencies and resists deflection for smoother finish. Mass in the head is particularly important, it takes a lot more to push the tool upward and out of the cut, so weight is your friend.

Thanks.

I think I’ll be going for the GH Universal.

Being 150% of the weight of my other option is too good to pass up.

Also, the power quill feed and easier addition of a power Z feed are too good to pass up.

Plus, a DC motor swap at some point in the future sounds like a fun project!


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