SuperMax 19-38 Drum Sander
Above: The SuperMax 19-38. The base is an optional extra that requires assembly.
Reviewed by Raf Nathan
SuperMax is a US company, although this machine is made in Taiwan. As a review machine the 19-38 came already assembled, however as a buyer expect to have minimal assembly of the main machine parts other than the optional in- and outfeed supports.
The optional base and support wings will need around 45 minutes of bolting together. This is a solid piece of gear with cast iron and steel main components. The heart of the sander is the large 5" diameter aluminium drum that comes with a 1.5hp motor driving it.
The machine has a strong, thick, cast iron and steel construction.
Below the drum is the feed belt which is driven by a smaller DC motor. There are two spring-loaded tension rollers either side of the drum to keep panels from ‘kicking’. A large handle winds the drum up or down giving in my calcs 1.6mm change per one rotation.
Abrasive strip is wrapped around the aluminium drum and clipped into place.
The comprehensive instructions state that it’s set up in the factory but I wanted to check of course. Best results are obtained of course with the drum aligned parallel to the feed belt. This is a painless process though, loosen four allen screws and adjust the spring-loaded 7/16" rise and fall bolt to raise or lower the drum to the platen.
The workpiece should make contact across the width of the drum. However to truly get it aligned I sanded a wide panel a few times and adjusted the height until it was pretty well perfect to 0.2mm, not bad hey. Once set, it seemed to stay set.
Strong thrust-bearing mounted handle for height adjustment.
The feed speed is adjustable via a knob, although the fastest setting is not exactly riveting. Maxxing out occurred at three metres per minute (1.8km per hour).
Electronically controlled feed rate is powered by a small DC motor.
The small motor for the feed belt and controller do have what is called Intellisand, which is electronic monitoring of the feed speed in relation to the amount of wood removal. In this way the feed rate automatically drops to avoid stalling or burning. As expected, after half an hour of review- style test sanding, the feed belt needed tightening. This is easy with the attached spanners adjusting the feed belt on either side.
The open-ended design is so that panels wider than the drum can be sanded. Theoretically with a drum width of 480mm you can sand up to 960mm in two passes. The abrasive belt used is cut from a roll and it’s best to use an existing belt as a guide for this. The belt wraps around the drum and is held by finger-operated levers, one of which is spring-loaded to maintain tension.
The 100mm dust port worked well.
A quality digital height gauge is included and this is easy to use. My experience was that it was easier to set the sanding height by running a piece of wood through and lowering the table to make contact thereafter – a third of a turn of the handle worked best. The digital gauge had some backlash so it was not as reliable for my style of use.
Digital gauge comes standard.
Initial test sanding was on some trays I was making, one of which was veneered with a solid frame. I was able to comfortably sand the frame flush evenly with the veneer without any problems. Burl and fiddleback came up beautifully.
Next up with great results was a 550mm wide slab of softwood using an 80 grit belt. Yes it was a slow process taking around 0.4mm thickness off at a time, but I could not have done it without the machine. The slab ended up nicely dimensioned and finishing off with a 120 grit gave an accurately thicknessed sanded panel. A 450mm wide figured guitar body that I had worked with a handplane was finished off quite quickly to a variation in 0.3mm across its width.
I reckon with more time tuning the alignment I could get a better result. Best was taking some wood straight from the planer/thicknesser and sanding a couple of passes with 180 grit. This gave a production-ready surface suitable for most feature work. Sanding higher than this was quicker with a power tool though.
The SuperMax is naturally better handling soft woods, but hardwoods are no problem, just a little slower. For the price you get a rugged machine weighing 155kg that should well suit small workshops and sole operators. Guitar and boxmakers, furniture makers and veneer users should like it. Machine comes standard with digital gauge but the stand, steel support wings and set of castors are extra. Abrasive belts can vary in price depending on quality and quantity.
Review machine supplied by Gregory Machinery. For information and pricing phone (07) 3375 5100, see www.gregmach.com