Pre-Mill Capability on an Edgebander

Advice on how to take best advantage of the pre-mill function on a new edgebander. May 23, 2007

Question
We are looking into a new edgebander. On the premill, how much material do people generally machine off?

Forum Responses
(CNC Forum)
From contributor N:
We only use the pre-mill when aprons or build-ups are used, and typically we mill 3mm. I think that is a lot more than we need, but our bander has no problem milling it.



From contributor M:
I had the same question about 6 months ago when we upgraded to a bander with pre-milling. You can take off anywhere from 0-3mm. I decided to make it a rule for our shop to take off exactly what they are putting on. For .018 (thin) banding, we take off .5mm and for 3mm banding, we take off 3mm. That way, we do not have to change the size of any of our parts. Our finished size is exactly the same as our cut size with or without banding.


From Brian Personett, forum technical advisor:
I think contributor M hit on what is pretty much the norm.


From the original questioner:
We have the software in place to take off any amount we decide. Would it not be much easier on the machine if we would only take 1mm off all the time? We band a lot of parts that are 1 1/8" thick.


From contributor K:
Does pre-milling ever cause a problem with chipping melamine coated boards?


From contributor M:
Almost all we do is melamine and the whole idea of pre-milling is to create the perfect edge for banding. Even the best setup on a beam saw will not give you as clean an edge as a good pre-mill station on a great edgebander.


From contributor K:
I understand what pre-mill is for - edges. The melamine is on the surface. We sometimes have melamine chipping problems, even with CNC compression bits. However, I would think that with the slower speeds of an edgebander, it wouldn't be as much of an issue. Apparently, it isn't.


From contributor M:
If the pre-mill tooling is in good condition the melamine edges are great.


From contributor B:
What edgebander are you looking at? We have a pre-mill on our Homag and we would never go without it again. It is even more important with thicker panels, as they are never cut perfectly vertical. The pre-mill unit takes care of all this.

We do 60 mm high panels and without the jointer, we only get glue on 1/2 the panel, as the panels are never perfect until they are jointed. Keep one thing in mind. In order to maximize tool life, you need to remove at least 1mm, otherwise your chip load is too low and your tool life will suffer. Same applies to CNC tooling - if your chip load is too low, tool life suffers. Remember, just because you have a pre-mill does not mean you have to use it. But if you don't buy it, you will wish you did.

We are in western Canada and I can't say enough good things about our Homag and the service we receive.



From the original questioner:
Thanks - that is exactly the kind of information I was looking for. We are looking at a Holz Her - Triathalon.


From contributor O:
We have a Holzher. I would not recommend it. Their glue system is impossible to adjust. It either starts too soon, ends too late, spills over the top edge, or leaves a void. The holes never line up with the panel edge just right and are always plugged with burnt glue. Go with a pot system; I wish I did.


From contributor M:
We have a Brandt KD 85CF. We had a KD 56 for about 6 years before. With the 56 we did not have pre-milling nor contour routing. The KD 85 has everything you would ever want on an edgebander. It is easy to change over from .018 to 3mm and back again. With the variety of work we do, we have to change back and forth 3 or 4 times a day. The support from Stiles is the best in the industry and although replacement parts are sometimes high, they have always had what we need in stock and can ship right away.


From contributor J:
I must take exception with contributor O. I would never own anything but a Holz-Her bander. To the contrary, their glue system is very precise and easily adjusted for all sides of the panel. Their parts department is very good and our local supplier has an excellent Holz-her certified tech. As far as plugging with burnt glue, standard cleaning and maintenance will take care of any issue.


From contributor V:
We have a Hol-zer mid-range edge bander. There is always something wrong with it. Of all the equipment in our shop, it gives us more trouble than all the other machines combined.