Hole saws would do this, quickly and also do the groove, in 2 operations. Much cheaper and faster. Or rotary table and small mill. Noel

Looking again at the original post, I think one of these small machines would be unlikely to cope with the 50 per day criteria. I would guess that in industry lids like those described would be churned out on an automatic lathe of some description.

John

I doubt anything 'hobby' will do 50 a day 100mm diameter and 20mm depth to be honest. Hole cutter and some sort of lathe fixture to tidy up the edges would be my starting point.

I cut some large gear wheels for a friend in 6mm MDF in sets of three sizes, the largest being 100mm. 15 wheels was 5 set ups and really tedious. I would have struggled with 20mm thick MDF, the machining time would have gone up 3x or so. I used a Sieg KX1, which was fine for the small quantity of thin wheels, if a bit tedious. I have the 3018T engraver from Amazon and it's certainly not got the guts to do that sort of work (it struggles to remove copper cladding from PCB with a 3mm cutter) even though the table size is a bit more amenable. I paid about £180 for the 3018.

A standard router mounted in a table would be quicker. At 20mm thick routing out on a cnc in one pass on a cheap CNC I would say is a no go. Quicker to rough saw on a band saw and rout the shape with a template.

Hello,

I have no experience of these mini routers, but I am doubtful that they would have enough power to do what you are suggesting, up to 50 times a day. In industry today, I expect they would be produced on automatic lathes, or CNC routers. In the past they would probably be produced using an overhead router, such as a Wadkin LS. Using appropriate jigs. (Used mine today, only to cut plastic tho!)

Handheld woodworking routers run at around 20,000 rpm, and are rated at around 1000-2000 watts. I use a 2000 watt router, with ½ inch cutter, ½ inch depth of cut to rout softwood staircase strings. In hardwood ¼ inch depth of cut is more comfortable. The downside of routers are noise and dust. The dust goes everywhere, as Frances said, and the high pitched noise, annoys everyone.

As HowardT said, a handheld router inverted in a table, and suitable jigs would do what you want, Bandsawing first will save a lot of strain and dust, and will mean you only need one pass around the outside. Both MDF and softwood will leave you a sanding challenge.

Using real wood, will mean routing against the grain, in two of the four quarters, leaving a rough finish, the less close grained your timber, the worse it will be. Sanding the edges of MDF is tricky, as the fibre ends tend to flick back and forth as you sand, it's a bit like sanding the bristles on a scrubbing brush!!

Turning the blanks on a lathe, would allow for sanding the edges at the same time.

You also have to work out how to hold your blank, whatever machine you use, as you are machining through 360 degrees, clamps are a nuisance. You can use a couple of wood screws, if the holes don't matter, otherwise you are into vacuum chucks, and more expense.

Wadkin LS

Wadkin LS Operating Guide

The operating guide, probably from the 1950's or 60's, has lots of information on jigs etc, including Tap and Die box making, my favourites are the jigs for spectacles.

Mark.

The biggest problem with the smaller machines is they don't have much grunt so feeds and depth of cut are quite low. I did see a video of a 3018 Pro doing a profile cut which is what you would need to cut the circle from a board and it was feeding at 200/min with a depth per pass of 0.25mm. ( did sound a bit low) Your 15mm thick x 100dia circle would need 60 passes of approx 300mm length so that is going to be 90mins per cut. Plus any additional time to form the lip and engrave.

By comparison my hobby mill would be quite relaxed going at 600mm/min and 2mm depth per pass so just under 4mins and that could be speeded up if needed. That could be improved more with a faster spindle as I'm topped out at 5000rpm

If you are having a lip than holding won't be such an issue as you can cut out the majority of the disc retaining it with say 3 small table. Then snap it out of the parent board and hold the other way up to machine the lip which will remove all traces of the tabs, simple MDF nesting jaws would hold the lid without marking and same jaws could be used for any engraving so minimal costs as the jaws only need making once and you are not spending out on miles of tape & glue or running a vacuum table all day.

CNC is also the way to go for any engraving unless as easy to change the pattern on the screen and bung in a USB stick.

As well as keeping the working enviroment dust free your main need will be to keep dust out of the cut, these small machines tend to run 1/8" cutters so you don't want them getting clogged up in a relatively deep slot so air blast to clear and the n collect the dust or run a vacuum constantly.

Alex

Have you considered this type of attachment for a bandsaw

Lumberjack BSC254 Variable Circle Cutting Jig Accessory Attachment for Bandsaw

You still need good dust extraction but less of a problem with sawdust.

If the sawn finish was unsatisfactory it would be fairly simple task to sand to improve the surface finish.
The router you mention should be capable of the lip and engraving, the router can be working as you saw the next blank.

Emgee

As you are machining wood products a router would be a better bet than a conventional mill, the latter generally being limited in maximum spindlespeed which even though the spindle power is higher than a hobby router would limit the feed rate. I think Jason has a KX3 – these are nice but the usual suppliers in the UK seem to have dried up, however the new price is a few grand if available.

Regarding the material, I would repeat my recommendation of Valchromat over MDF. It's a much nicer material to machine, kinder to cutters and the dust is far less toxic than MDF, and needs little (or no) finishing to be decorative (and it's coloured). It is more expensive and hardish to get hold of. For specials you could consider Corian, lovely to machine, offcuts can be had from specialist kitchen suppliers often for free. Also available in various colours and finishes.

For quick routing at useful depth I guess you would need the equivalent of a reasonable handheld router as the spindle, at least 800W but better 1000.

I received a mailshot about two new CNC milling machines from Chinese company Titan Machinery that are aimed at the small workshop. They don't appear on their website but the specification of the larger one looks quite nice with 8k spindle, AC servos, linear rails and 8 port tool changer. I guess this is similar to the Syil family ? I have no affiliation to them, who they are etc but thought it sufficiently of interest to post details here.