Preventing Tearout on the Shaper
Climb cutting and taking multiple passes are suggestions, but a good power feeder setup is safer and more cost-effective.August 27, 2012
Question
I'm using cope and pattern cutters more and more instead of mortise and tenon, and also bought a lock miter set of cutters. I'm finding with both sets I'm getting too much tearout in the grooving cut area on the edges. What can I do to reduce tearout? All my cutters are Freeborne, sharp and clean. The shapers are both top of the line General.
Forum Responses
(Solid Wood Machining Forum)
From contributor D:
Relief cuts to remove heaviest amount of stock on tablesaw first, cuts taken in two or three passes, slowing your feed rate, and climb cuts help. Climb cutting is dangerous; if you aren't familiar with it you should read up and prepare before jumping in head first. Some woods are more prone to tearout as well, like Douglas fir. I gotta say, new cutters ought to be making parts slick as glass.
From the original questioner:
Thanks. I'm a small custom shop doing various pieces of furniture. I was hoping to reduce tearout without feeders and climb cutting. I think your multi pass idea is the way for me to work. Production setup is not practical for my shop.
From contributor D:
Couple of things I forgot. Been doing them so long I don't even know I'm doing it. On rabbets, especially curved stock, I take a swipe climbing - just a touch, maybe only 1/32" comes off, before pushing my stock all the way against the bearing. It takes experience, so hold the parts as if they will pull away from you, not into your gut, hands, etc. Works wonders on edge tearout. Don't do this if you aren't one of those manual dexterity types. It's like carving or anything else, just using a shaper. Actually I suppose you could be safe and use a bearing just a tiny bit smaller than the cutter, but I never have.
Also on linear stock look down on the face and look for grain runout. I always feed with the "points" of the grain never pointing into the points of your cutter's angle of attack. Just flipping some pieces end for end make a world of difference.
From contributor J:
Even as a small shop at some point you have to account for your time. Taking the time to run multiple passes is costing you money that could likely be better spent.
I highly recommend you invest in a power feeder. Not only will you eliminate your tear-out problem, you'll also produce a better quality profile requiring less sanding. Not to mention the safety aspect, or the amount of time savings you will realize not running things several times.
I would never recommend climb cutting without a feeder - no good way for that to end. With a decent quality shaper and a feeder, you won't need to bother fooling around trying to climb cut anyway. A used model can generally be had for under $500, which I think you will find to be money invested wisely.
From the original questioner:
Contributor J is probably right. The shaper is a tool that would be safer with a feeder. And the work would no doubt be of a higher quality. I'll keep that purchase in mind. Thanks.
From contributor D:
Contributor J is right and I regret now saying anything positive about climb cutting without a feeder. A feeder is a wonderful tool that will contribute to your safety as well as the quality of your work.
From the original questioner:
Any brand suggestions?
From contributor D:
They're all good to me. We have a few brands and they've been trouble free for about 20 years or so. The few failure points have been the cheap cast metal parts stripping out on chiwanese models. One expensive Italian made one (can't remember the brand - it was white with orange wheels) was the only one that really failed, with the transmission needing something as it slipped out of gear all the time. They're simple and straightforward machines - the one that failed on us we were told was an easy fix, but at the time we were so busy the owner just went and got a new one, and we were rolling again in an hour or so. I'd think you can't go wrong getting any brand, and it's definitely a buyer's market these days.
From contributor J:
If money were no object I'd go with a Univer. They're much more expensive than the rest of the pack, but I prefer the way they adjust.
I have a Univer in my shop as well as a Delta 4 wheeler and a Festo 3 wheeler. They all get the job done. Another thing that's nice to have is a good variety of speeds - not essential, but handy. Oh and at some point depending on whether you buy new or used, you'll want to convert to the urethane wheels Western Roller sells. The rubber ones don't hold up too well and lose their grip rather quickly.
But again, any feeder is better than no feeder, so get whatever you can find and afford and go from there.
From contributor I:
Try sizing your material to width and 1/8" oversize, then shape it in one pass to net width. Helps if you run it between a fixed fence and the cutterhead, with a power feeder. Look at weaver-sales.com for their sticking plate. With sharp cutters, that combo will get you tearout free, consistent width stiles 99.9 percent of the time.
From contributor W:
Are you using the full profile and removing a small amount or at least getting the entire cut? If not, try moving your fence until you get a full profile and see if it is without tear out. You may need to use a split fence or build up the outfeed side by the amount you remove to avoid snipe.
