The smartDisc idea has been sloshing around in my head for a long time.
The idea is to offer an 18″ diameter bench-mounted disc sander WITHOUT an adjustable angle table, but WITH an adjustable HEIGHT table instead.
For the reason why, click on the ‘why?’ tab.
As those of you who’ve been on a course with me will know, I have a few things to say about disc sanders and how they should be designed. They’ll also know that I have a big one – and where disc sanders are concerned, size does matter.
I’ve always been perplexed by the poor design of disc sanders – I have two main issues with almost all commercially available machines:
1 – tilting table:
A tilting table is a bell, it’s a whistle, and as with most bells and whistles it’s not necessary. And yet all manufacturers, seemingly without exception, appear to believe that disc sanders need tilting tables.
NO THEY DON’T …
– bicycles and fish suddenly spring to mind for some reason …
Almost every conceivable job can be done by angling/rotating the work laterally, far more secure than having the work tilted down. On the very few occasions when a compound angle really is required, this can be achieved by tilting the work UP from the table – again, much more secure.
2 – height:
What would be FAR more useful is an adjustable height table – but this barely exists except on large, free standing, pedestal-style machines. A disc sander is an important, multi-functional machine, but the best part of the disc is always wasted by what, in my opinion, is the incorrect positioning of the table. To have a table exactly halfway up the disc as most are is absolutely the worst and most inefficient place to have it, effectively reducing a 12” disc to a 4” usable width. And even that involves a large speed differential across that small distance …
which is where Frank Zappa, my wonderful 24” twin sander, comes in. Hi Frank!
Made by the German company Friedrich Zimmermann, it’s a sturdy cast 1960’s machine, and the only three-phase machine I possess. Not actually health and safety compliant – no guards [doesn’t everyone remove these useless obstructions as soon as the machine comes out of the box anyway?!] and despite there strictly speaking being a requirement for a brake to ensure that it stops in 12 seconds, when going full tilt it actually takes 50 minutes.
You will no doubt have noticed that the tables on this machine are actually fixed at what I’ve made clear I consider to be the worst possible height. But the bigger the diameter, the less it matters where the table is …
Notice that the extra height afforded by the mdf packing pieces placed on the table raises it well above the useless middle of the disc and allows a shallow arc, an excellent, wide, controllable sanding area with very little speed differential.
Simply put, having the table in this raised position does three things:
• significantly increases the usable width of any given disc
• reduces the speed differential across that width
• reduces the upward grabbing tendency of the rising part of the disc
On my 24” discs this actually gives about a 15-18” usable width depending on the actual height of the table, on an 18” disc around 12-15” – with very little speed differential. Compare this to the 4” available on a conventionally set up 12” machine, and with a very significant speed differential.
so what next?
There’s definitely a need for an intelligently designed 18” disc sander, so I’m intelligently designing one.
I’ve made several disc sanders and I’m now pretty clear about what’s necessary and what isn’t. Needless to say, none of them had a tilting table … but all have featured a table considerably LOWER than half way – this allows the table to be effectively raised to any height using scrap.
The largest bench mounted machine available seems to be 12”. What I will be offering will be a high quality 18” fabricated aluminium faceplate, together with plans for building a robust and simple framework around it for bench mounting, enabling high, middle and low table positions, and efficient dust extraction.
This project has been on the agenda for some time, but due to problems with the smartWare has been rather sidelined. Now, as everything in that department seems to be going smoothly at last, I’m hoping that I will get this up and running by early 2018 – watch my newsletters and the WW press for news.
The extensive smartBoxmaker Research and Design Facility is working away feverishly on this as I write …