Choosing a Widebelt Sander

A discussion of widebelt sander capabilities, the function of the platen, and more. November 6, 2007

Question
I'm ready to buy a 2-head 43" widebelt, and went to AWFS to look at what is available. This will be my first widebelt, and I am a bit confused as to what options or features are really important.

Broadly speaking, there seem to be two head/machine designs - euro type with pneumatic head positioning and actuation, often with air platen, and what seems to be an older style seen in far east imports with fixed calibrating head and manual platen setting.

This will be used for cabinet door production - both panel prep and finished door sanding. Solid wood only right now, including very hard and dense woods. My budget covers entry level machines like Timesavers 1300, Butfering 211, and Holzher/Boarke, and possible European manufactured machines like Houfek Buldog, SCMI, and Biesse.

I enjoy working with high quality and well-designed equipment, but am not sure what features are really important to my needs. Feed belt tracking, panel cleaning brush, abrasive belt blower, auto thickness setting, etc...

Forum Responses
(Cabinetmaking Forum)
From contributor M:
We are currently looking at purchasing a wide belt sander as well and we did check out many of the manufacturers at AWFS. What we've learned (mostly from talking to salesmen) is that a platen isn't really necessary unless you want to do some very smooth finishes or you are sanding thin stock such as veneers and what not. The platen is soft and therefore will tend to ride the contour of the surface of the material rather than sand it down to precisely the thickness you are going for. Of the sanders we looked at, we were most impressed with the Viet machines out of Italy. They are priced very competitively and offer pretty much all the options the other guys offer such as automatic calibration and so on.



From contributor J:
Yet another variable! I read the Viet rationale for drum only sanding and am now even more confused. I thought the platen just barely contacts the calibrated surface and gives a less scratched surface than a single contact point. The trapped dust decreases the penetration of the grit into the wood and gives a finished surface comparable to a higher grit drum (using 180 on platen to get 220 drum finish).

I can see how a 3 or 4-head all-drum sander would be sweet in terms of abrasive belt life, accuracy, and power requirements, but that is out of the budget.




From contributor W:
If you are making doors and need a 2-head sander, either 1) you are a cabinetmaker, and probably should be buying doors, or 2) you are trying to grow your door business, in which case a 2 head sander is only good for your transition to a larger sander later on.

Consider a cheaper (Grizzly) 2-head 36" sander to hold you over until you can get the larger sander. If it is just for doors, the narrower sander should work for a few years. If you can swing it, consider a 3-head 36" from Midwest Randbright. This is not loaded with features, but is built like a 1950's Chevrolet - solid and simple.

The Viet machines are very impressive, but I have had too many problems getting parts from overseas, regardless of how many parts they say they carry, etc. If you depend on it, get USA made.

Sand your panels once - in the door after assembly. Sanding them first is a wasted step.

If you are finish sanding a door, you need a platen and 220 grit. 100 - 150 - 220 should work. For several years we were at 80 - 120 - 180 - 220 on our 4-head, but are going to 100 - 1xx - 180 or 220 - 280 so our orbit machine can take out all the cross grains with a 220 grit. Using a rougher grit on the orbit machine leaves swirl marks. Using 220 on the wide-belt left crossgrains, and we have been pre-sanding crossgrains before the orbital, until I just decided that has to stop somehow. This last combination has given us the right results. Most shops do not go to this level of finish. Make sure you do stain tests...



From contributor T:
I thought the platen just barely contacts the calibrated surface and gives a less scratched surface than a single contact point. The trapped dust decreases the penetration of the grit into the wood and gives a finished surface comparable to a higher grit drum (using 180 on platen to get 220 drum finish).

This is pretty much correct... You do need a platen. You adjust it to smooth out the drum marks... that's all. You don't calibrate with the platen... that's what the drums do. When running cab doors we always run them at a slight angle... maybe 10 degree. Drum and platen ease up on edges and also leave less burring (blowout) on trailing edges of stiles/rails. Last pass with 220 (platen only) will do real nice job - ready for hand sanding... RO or fladder.

And again, buy the better sander as you mentioned. A sander will last a long time, so get what you need for the foreseeable future. The 43" will enable you to sand most anything, even other shops' work, because they only have a 24 or 36. Been there, done that, and it cost more in several ways.