Molding Knives on Surface Planer

[Ray Frederick]

Hello,

I'm a carpenter and cabinetmaker and I'm in need of a planer that can take molding knives. I know all of the modern lunchbox planers are incapable of this and I can't afford a Woodmaster or Williams and Hussey right now. There are a bunch of older Sears planers available on eBay and Craig's list, such as http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=150338058926#description , that look great if you think I'd be able to grind a knife on a blank piece of steel to the same dimension as the straight knives and use that for profiling.

I know how to grind knives and balance as I worked at a custom cabinet shop, I'm just not sure if the cutter exposure and the like on one of these vintage planers would allow for that or if I have to suck it up and save for a Woodmaster.

Thanks,
Ray

[Brian Peters]

Although its been done in books and finewoodworking I strongly advise against grinding your own knives with a bench grinder. If you have a template knife grinding machine that's one thing but this is not a safe diy project. Balance is key and playing with sharp knives is not for everyone.

Look into buying a used w&h if you can't buy a new one. If you can't afford that then you shouldn't be making your own molding for your jobs and should be outsourcing it to someone with the capability to s4s and run the molding for you. Or you should look into getting a shaper with a power feed and running a lock edge cutter head, but the w&h is far more efficient.

[Ray Frederick]

Brian,

The snide response was not appreciated. I asked a simple question regarding the ability of certain planers to run a profiled knife, I have seen the profiled knives for sale but wanted some first hand experience of a planer capable of running them.

Your analysis of my finances and whether I should or shouldn't be running custom molding had no place, I've run a 5 head molder before and ground plenty of knives on a template machine(which I do have access to , as well as knives I already own) and a grinder. I have a specific need for some short runs of molding and I'm tired of grinding shaper knives and making do with routers and the shaper, a simpler planer that can accomplish this as well as jobsite stock thicknessing would be great.

So if anyone has experience doing this or can point me to an article regarding the use of molding knives in any of the products marketed as thickness planers(specifically the older cheaper Sears units that are a dime a dozen now) I would really appreciate it.

[Rick Lizek]

There really isn't enough room in a standard planer to accomodate a profile knive as you know. There are plenty of old Belsaw moulder/planers out there for cheap.
Nothing wrong with grinding your own knives on a grinder and nothing wrong with a single profile knife. Do you know the formula to get the right profile???

Have you seen the Shopfox moulder? Half the price of a W & H and uses the same knives.

[Alister Orme]

I was looking on OWWM at
http://www.owwm.com/pubs/222/606.pdf
It looks like there are no feed rollers and you'd have to hand feed and depending on the profile rigging a dependable system for kickback that isn't going to scuff up the molding would be difficult.....easier to go to a shaper

Sears made a lunch box sized 13" planer /molder similar to the griz and jet that sometimes go cheap as well.

Good luck.

[Peter Quinn]

I too have run a molder, seven head in my case, to make flooring and moldings. I work for a millwork shop that specializes in custom moldings of all kinds. I have not ground my own knives and can't offer much there. I can tell you that knives ground to pattern on automated equipment from CNC templates sure are nice.

I don't think any dedicated planer worth owning can spin any molding knives worth spinning for money. A decent planer needs a chip breaker and possibly a pressure bar in close proximity to the knives so there is just not enough room to spin a molding knife in there. Most planer knives are 1/8" stock, most molding knives are at least 5/16", and for a reason. There is I'm sure you are aware a specific depth of cut per mill thickness of steel for knives, and 1/8" knives are very limited in terms of projection and thus depth of cut. You might find a big planer that can take 1/4" per pass, but the knives are all in one plane with no tight curves and fine projections. The points on a typical molding knife would likely snap off if ground in 1/8" stock, so keep that in mind.

Typical 5/16" molding knives (corrugated back 60 degree or W&H style) give you about 3/4" depth of cut. That is what the steel can handle regardless of the machine spinning it. Most small molders are designed to handle about a 3/4" depth of cut, so that works out well. All that aside, multi knife heads need some means of alignment for the knives, and they really need to be ground to pattern quite precisely, so I'd guess you are talking about a two knife head running a single knife with a balancing bar in the other jib? I work with a guy that ran a Woodmaster in his own shop with a single knife set up and claimed it worked great. Key there was VARIABLE SPEED. Slow the feed down to keep the CPI (cuts per inch) up and you get great results. I'd guess most old Sears planers are NOT variable speed? So plow a piece of molding through a single knife machine at 24 FPM, what do you think that is going to look like? I have a 2 knife shop fox version of the W&H (with variable speed), and I can tell you that at 24 FPM blind relief cuts are about all I can do. I have to slow it to produce anything that is not loaded with chatter.

I'm not trying to be discouraging or insulting, just thinking out loud so to speak in case any of my thoughts offer any use. I think the cards are stacked against you on this one but would be curious to know if you have any luck with it.

[Steve Jenkins]

I used to own an old sears planer molder. It was made by Foley-Belsaw and worked fine for running molding knives. I think that without actually looking at the machine a person couldn't know if it would work or not.

[Peter Quinn]

I used to own an old sears planer molder. It was made by Foley-Belsaw and worked fine for running molding knives. I think that without actually looking at the machine a person couldn't know if it would work or not.

So you're saying the old sears machines are belsaws? I seem to remember some older sears planers that were NOT molder planers and would not be suitable for molding. But any machine based on a Belsaw molder planer should make moldings. Did they have variable speed?

[Ray Frederick]

Thanks for the great replies guys. I've used an older Sears molder that was a Belsaw (apparently it was a predecessor to the Woodmaster) and it looked quite different then the feed roller-less model I referenced in my first post, it did indeed take a set of single profile knives and it worked quite well.

I had stumbled across a reference in a manual and in a parts list to molding cutters for one of the non-Belsaw Sears planers. I was having a hard time coming to grips with how the machine handled molding profiles with the limitations in edge guiding, speed, and the like and figured someone might have some experience with it but perhaps it was such a bad idea it was scrapped after one model run. The Williams and Hussey machines are going for very high prices locally even used so I'll just keep my eyes open for an old Belsaw unit for the time being and continue with my shaper and an assortment of router bits and jigs. Thanks!

[Jeff Wille]

Here's a "lunchbox" style planer that can do moulding. It's still pretty heavy, though.
http://grizzly.com/products/15-Planer-Moulder/G0477
I was very close to getting this one, and I ended up deciding against the purchase of any moulder (due to the cost alone).

You can also buy a blank knife set from Grizzly for this planer/moulder and make your own shapes.

It looks like a great machine, and I am a big Grizzly fan.

It's also got built-in dust collection. A bonus?? For me, it would have been.

Good luck with your project/purchase/plan!

[George Sanders]

I bought a Belsaw 910 with a 3 horse motor last year for $295. It even came with a few molding knives too. Keep looking and you'll find one cheap.

[Jim Becker]

Ray, I don't think that Brian intended in any way to insult you, although I can appreciate how it might have come off that way at first. But the cautions he raises are valid and there are many thousands of people who view SMC who may not realize that grinding identical molding knives requires the right setup, etc. You do know that and are looking for the right way to do this.

In addition to the tools mentioned, there are a few machines that have been around for awhile that are dual planer/molders and marketed by the "usual suspects". Jet, for example, had one in the line for a very long time and it's similar to machines with different name-plates. It's a "small stationary machine" with, if I recall, 13" of planer width and the clearances to use molding cutters. You may be able to find one via Craig's List. Finding one of the Shop-Fox or W&H machines, even a very old one for the latter would be nirvana, however!

[Bryan Cowing]

I still have my old Foley 12" planer-molder I bought in 1980. I now run a large and a small set of crown knives in it. I use the Asian made knives meant for their planer-molders, similar to what Grizzly sells in the US. I have to reduce the width of the aluminum holding blocks a 1/16" to get them to fit. :D

[Chip Lindley]

Older Sears 12" planers were made by Belsaw and moulding knives were offered as an option. Many swear by these for making moulding. RBI (RBIndustries, just now out of business) made a 12" planer very similar to Woodmaster's which also held moulding knives. All of these had power feed rollers. They all held 1/4" thick moulding knives in the planer head. All are worth a look for your purposes! During these *down-times* I am sure there are some serious bargains out there!

[Joe Jensen]

In the late 80s, a friend bought a used (1970s era) belsaw that could take moulding knives. The used machine came with a couple of sets and we ran some stock just to try it. I've seen those old belsaw planers on ebay and craig's list for a couple hundred bucks. My friends had a 5HP motor so it had plenty of power.

Like a previous poster said, I think Sears sold a planer made by Belsaw...joe

[Eugene Beverage]

I had a sears planer/moulder just like the grizzly-GO477 that was junk.I planed approx.100ft. of oak and broke the chains that ran the infeed and outfeed rollers. I called sears and complained enough that they agreed to replace the planer.I received the second planer and did not plane 100ft. of oak and it broke the chains and it was returned for a refund and I went with a Grizzly GO453 planer. As you can tell I was not very happy with the sears planer/moulder. I also have a sears 12 1/2in planer/moulder mo#351.233831 that is a good machine.I still have it and use it for moulding only.

[Dick Bringhurst]

I've seen Jet 15" planers the will take molding attachments. I don't know itf they are made any more. Dick B.