Message Thread:
Melamine chipping
2/9/26
Have been running it for 2.5 years now, had it set up by Homag
On white 5/8 melamine (uniboard or panolam) i get occasional chipping, sometimes real bad chipping all along the edges
Have talked to my bit supplier, they've thrown any bit at me, and no improvement, they even went so far as to sent me a hydraulic toolholder which is supposed to minimize vibrations
Right now I'm running a 3/8" compression, with special coating, 3flute with 1/4" mortise tip.
Have also tried the equivalent without the coating
Bits are cool to touch right after cutting
Feed speed is 19 meters per minute
And 18000 rpm
Leaving a 1mm onion skin to cut for the second pass
Bit supplier is at a loss as to what to do next
When i put a new bit in then things inprove, but after 10-15 sheets its chipping again
I used 2flute bits in the past, but worse results.
Funny thing is that some pieces are quite fine, and others are very chipped, also my dados are chipped, but those are getting cut with a standard 3/8 downcut bit
Even on high quality textured melamine i get chipping but then only where the bit enters the material just one small chip(really annoying) but other than that good results
What would cause that initial chip???
Anyone that can help me out with this?
The chipping is only happening on the top normally
When it chips at the bottom it's generally due to a bowed sheet not touching the spoilboard properly or a dull bit tip.
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2/10/26 #2: Melamine chipping ...
drop down to 14000 at 11 MPM. If you get a good result start working you're way up from there. If not, you probably have something loose in the head of the machine. Loose bolts?
2/10/26 #3: Melamine chipping ...
Had this from day 1?
Try a different board.
Your comment about the board being bowed and not held down is also a huge red flag.
Unless you are running only large pieces, you should be using 2 flute as the acceleration curve of the machine may not get you up to 19mm/m on smaller parts.
Climb or conventional?
Is the chipping happening on the first or second pass?
Based on your board I assume you are in Canada. If you haven't done so already try FS Tool coated compression spirals. We tried another brand and got chipping on the top of the board.
2/10/26 #4: Melamine chipping ...
With intermittent chipping I would first look at the spindle taper. Is it clean? Does it have any burrs or debris caught in it? If not, do the chips tend to be in the same location on the table or random?
2/10/26 #5: Melamine chipping ...
First off it looks like my original post got messed up, it's missing some of the text at the top
Machine is a 2008 Weeke vantage 32S
I bought it used, but got Homag to set it up and completely go over the machine
To Cris:
I can try that, but that seems very low
Main spindle spins very nice and freely, and if something was messed up there then everything would be messed up and chipped, but on textured melamine its cutting clean except the entry cut.
To Dropout:
I used Panolam at first, but quit using that due to chipping, been using Uniboard instead with mixed results
What do you mean by climb or conventional?
No I haven't used FS tool bits yet, i suppose I could try that
My current supplier has gotten me to use every type of Royce bit out there, I'm not sure if FS Tool would improve things.
Chipping happens on first pass i believe, but i would have to double check that.
To Tom:
Good point, i should check the spindle for any dirt
The chipping is random all over
2/10/26 #6: Melamine chipping ...
I spoke to Royce rep this morning and they said my feedrates etc look ok, they're going to look into it further
I'm at the point of returning all my stock of royce bits to the supplier and getting a different brand
2/10/26 #7: Melamine chipping ...
I had an experience where I was getting chipping with RA coated bits but not FS.
Google climb cutting - will be better than me explaining. We climb cut first pass and conventional the finish pass. Do you do the first pass oversize? we do 0.5mm.
2/10/26 #8: Melamine chipping ...
I do conventional for both cuts
No i don't offset the first pass, i know in my software it is an option, but i remember the tech support guy said" that's only for cheaply build machines that have deflection, a Homag shouldn't do that"
I wonder if i should try that though
2/10/26 #9: Melamine chipping ...
Website: http://www.bhdavis.net
Forget what the support tech said and try a step out offset that is greater than the size of the typical chip. I'm not saying it will solve the problem but no harm in trying.
Also in the areas of chip out at bit entry point that could be the bottom of the compression bit. Do a test cut with a downcut spiral bit ignoring the bottom of the sheet for the test. It will show you whether or not its the compression bit causing the problem. If it does solve the problem than one solution would be to cut through to the onion skin with the downcut spiral and then switch to an upcut for clearning away the onion skin. Again no guarantee it will solve the problem but easy to try.
The more information you have from various cutting methods the easier it's going to be to find the problem.
BH Davis
2/10/26 #10: Melamine chipping ...
I've been cutting melamine for a long time. My chip load target is 0.0185, meaning with a 3 flute bit I run 1000ipm at 18k. Reduce speed for 2 flute tools. The only time I have had chipping was due to my board supplier. Change that and the chipping went away. Good luck, but if the machine checks out and the spindle has been trammed properly, I guess its the board manufacturer.
2/10/26 #11: Melamine chipping ...
To BH Davis: im going to give this a try soon
But given that my dado bit(which is a downcut) also chips the cheap white melamine
But i could indeed solve the entry chipping with that on the textured melamine.
To Mike: wow thats fast!! I feel like it'll be pushing my pieces around like crazy when I'm routering smaller pieces, haven't had bits breaking yet at that speed?
2/11/26 #12: Melamine chipping ...
I use FS Tools uncoated compression bits with good results. I can run them until quite dull without chipping. I also cut Uniboard, Panolam Tafisa and others without chips. Mine is a lightweight cnc so my feedrates wouln't be of any use to you.
I don't think this is a board or bit issue. Royce bits are very good and if the sheet goods were a problem, there would be a whole lot of complaints coming in to your supplier.
I would be looking for machine faults.
2/11/26 #13: Melamine chipping ...
i've complained to the suppliers about the chipping issue before, and you know what their standard response is right? "but sir, we've been having such good feedback on this product" they'll always deny that their product is at fault
another example: Uniboard sheets are always bowed the 4ft way, same response from the rep
none of them seem to tell the full truth or actually take it back to the manufacturer and do something about it
I guess my machine is 17 years old but relatively low hours, I thought Homag is a premium product?
their customer service sure isn't btw. absolutely useless!!
2/11/26 #14: Melamine chipping ...
Gerben,
No bit breakage, but I have a very heavy machine with a 24hp spindle. We also have a 40hp oil ring vacuum pump. I have always thought that type of pump pulls a deeper vacuum than rotary vane style. I've used them both over the years. If you can't cut at those speeds, don't waste money on 3 flute tools. Stick with 2 flute tools and slower feed rate. For reasons I don't fully understand, I get a better cut on Ultralight MDF with 2 flute tools at the same chip load as with the 3 flute tool.
2/11/26 #15: Melamine chipping ...
I also use a Komo with 16HP spindle and 40HP liquid ring pump.
My Komo is 16,000 pounds. My buddy's new heavy duty Biesse with more bells and whistles is 9,000 pounds. They are not the same.
2/11/26 #16: Melamine chipping ...
To Mike:
Wow 24hp thats wild!!
Mine is half of that which i thought was pretty standard
My machine moves pretty fast though, but who knows, there's probably faster out there.
I use 2 becker vane pumps, 8hp and 9hp i believe, but only use the 8 when needed for bowed sheets or small parts etc.
3 flute can give better results i understood, but only if you go fast you're saying?
Dropout:
Mine is just shy of 8000lbs, Homag advertised it at the time as "fastest and heaviest machine in its class"
Brother of mine in Europe invents and build machinery, he was very impressed with the build quality etc.when he seen my Weeke Vantage
2/11/26 #17: Melamine chipping ...
I did some testing today
first off I tried offset cutting, although I did get cleaner results, it somehow messes up the programming and causes the onion skin to be the correct size, but the main part is the wrong size
second I tried using 2 different bits, first up to the onion skin with a 2 flute downcut, and the onion skin with a 3 flute mortise compression, very nice results without chipping, but still a bit excessive onion skin showing
not sure how to fix this, I think it has to do with having each bit entered as a slightly different diameter, they're both 3/8" bits, but they never seem to be right at 3/8"
I also cut some dados for blind dado construction cabinets, but decided to router the dado a half mill deeper, instantly clean dado's, I guess that tells me that bit is dull right at the top of the dado, because I do all my dado's at 1/4" deep i'm guessing it's just worn too much right on that spot after 60-80 sheets
2/12/26 #18: Melamine chipping ...
A lot to try and figure out from this post. If you are cutting dados with a mortise compression bit, the upshear portions is 1/4". That will chip. Going deeper will get the downshear portion at the top of the board for a better cut. As for sizing, I can tell if its the compensation method or not. Also don't know if climb or conventional cutting. When conventional cutting, the tool load will slightly pull the tool into the board. My method is to leave 0.008" of stock on the onion skin. Finish cut will be net. Gets a nice edge cut without the little step at the onion skin depth. Climb cutting does not have this issue, but from my experience less tool life. Microvellum does not allow a rough cut on the onion skin, but the edgebander premill takes care of the step. Melamine is cheap. Try a different brand if you are still having issues, but based on your post, I would guess the problem is programming technique or tooling choices. I've been using Arauco for a while.
2/14/26 #19: Melamine chipping ...
I don't use my compression bits for dado's(my bit supplier thought that too lol)
I only use down cut bits for dado's
I'm not sure if I understand you correctly, but you're saying you leave a 0.008" onion skin? that's super thin!
I do 1mm which seems to be standard
I cut everything conventional
2/14/26 #20: Melamine chipping ...
No, I leave 0.008" of stock to be left from the net cut. I leave 0.03" from the spoilboard in depth on the onion skin. That gives me the best finish cut. In Alphacam, those are my most used styles out of all. I literally have hundreds of styles, depending on what I am cutting.
2/16/26 #21: Melamine chipping ...
How's your spoilboard working? Are you getting any part movement? I had a similar problem & tried everything you're doing. Changed my spoilboard setup (unrelated issue) & haven't had the chipping since. I'm not positive, but I suspect my parts were vibrating very slightly & causing the chipping issues. I have a BIesse Skil 5 x 12 machine with two Bosch vacuum pumps. I thought I had tons of vacuum, but with a leaky spoilboard I didn't have near as much vacuum as I thought.
2/16/26 #22: Melamine chipping ...
Good point, it is a possibility, so what did you do different?
If the vacuum gauge is reading high, then doesn't that indicate good vacuum?
2/16/26 #23: Melamine chipping ...
Originally I was gluing a new spoilboard onto the original one so that I didn't have to unbolt it & replace the whole thing. I had the bright idea when they were setting up the machine & the Biesse tech told me to do it. He said it would be fine as long as we sealed the edges good. It was ok for a while, but the top spoilboard would just peel away from the other one & create leaks. The face of the material isn't strong enough to hold together for a lot of use. I ended up going with Ulti-Board. It's a 1" thick spoilboard material that comes with the edges already painted. I had to have two pieces because my bed is actually 148" long. I created a dado at the joint & glued in a piece to seal it up. Also replaced all the gaskets. Since then our chipping problem has went away. I use Frost tooling, but I have some other brands as well as some cheap crap from Amazon. Don't really have any chipping problems anymore unless a tool is getting dull.
2/16/26 #24: Melamine chipping ...
As far as the vacuum goes, I'm no expert, but what you should be looking for is the difference in vacuum reading from an open table to a table with a new sheet ready to cut. If you have a filter clogged or some sort of blockage you could still get a high vacuum reading, but not be getting enough suction to your parts. A lot of it depends on where your vacuum gauge is located.
2/16/26 #25: Melamine chipping ...
you screw the spoil board down?? into what?? I've never done anything but to lay the spoil board right on the factory phenolic grid table
I don't think there's even holes to screw it into
and what do you do every time you resurface the spoilboard? sink the screws a bit deeper?
I've seen ads from the Ultiboard, but wouldn't know where to get it in western Canada
2/17/26 #26: Melamine chipping ...
We always screw down the spoilboard. Our 5X10 Komo has something like 32 screws.
On other machines we have drilled and tapped the bed and put threaded inserts in to use 1/4 20 nylon screws.
Makes a word of difference.
2/17/26 #27: Melamine chipping ...
Same here. Our Biesse came with the phenolic tapped for screws. You predrill a pocket in the correct pattern on the new board before you replace it. The screws stick up about 3/8" or so above the phenolic when it is all said & done. Once you surface down to the screws it's time to replace. Not sure about the chipping issue, but it would help your vacuum for sure.
Ulti-Board might ship to you. To find out you can contact Clay Workman - Clay.Workman@Ulti-Board.com. I'm not saying that it's the best spoilboard out there. I don't really know. They were the first ones I tried when I was looking for something better & it worked great. I set Ulti-Board up with one of our local distributors & now they stock it. Helped them & me. Now I don't have to pay shipping.
2/17/26 #28: Melamine chipping ...
I don't really understand how that helps the vacuum
once it sucks it down it'll suck both the sheet and the spoil board down right?
I'll take my spoilboard off today and will see if my Weeke has holes for screws
2/17/26 #29: Melamine chipping ...
It helps by making it seal better against the gaskets & keeping it from warping & popping up. You also don't have to flip the spoilboard when it warps.
2/17/26 #30: Melamine chipping ...
Ok that's interesting
I just checked
Mine has 2 matrix grid tables at 4ftx4ft each
Each has 4 threaded holes only
Since its homag im willing to bet that it metric, I'll have to hunt down some metric nylon screws
2/23/26 #31: Melamine chipping ...
Definitely check your filters. Better yet just buy new ones and have spares on stand by. They may noy look clogged but I had neglected mine then was frustrated with shifting parts.
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