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Large Plainer and Jointer Limitations

M.B. Naegle

Diamond
Joined
Feb 7, 2011
Location
Conroe, TX USA
Many of our customers use hydraulic cut-out machines that use steel-rule-dies (like cookie cutters) to cut through leather and other materials into big red or white plastic cutting pads that I believe are polypropylene. When the surface gets too cut up, you either replace the pad or if it's thick enough you can surface it down and keep using it. We used to offer that resurfacing service as we had a special machine for cutting the pads down. It had a carbide insert milling head like a face mill that was attached directly to a motor on an articulated arm that the operator could swing around to hit the whole surface and then adjust the arm down to cut more. It took forever and we were losing money (in time) as new pads were not that expensive, but an ex-employee got ham-fisted tightening a pad down and broke the machines cast iron frame. We could have fixed it but took it as a sign, scrapped the machine and discontinued the service until we could find a more economical way to do it.

I've been looking at Plainers, but was recently fixing up an old 6" Oliver Jointer of ours and am thinking that they might do the job too. We would need something with a cutting surface around 24" wide, as most of the pads ar 18 to 20 inches wide and are anywhere from 3 ft. to 6 ft. long. The pads are 1 to 2 inches thick, but often are glued down to big maple cutting blocks or plywood pads, so they'll be anywhere from 1 to 6 inches thick. We would only be cutting 1/8" to 1/4" down in as many passes as it would take. Our old cutter used to have a HSS cutting head, but we switched to the carbide head as we had a few pads with bits of broken dies embedded in them, which were a pain to find.

So I guess my question is could a 24" Plainer or Jointer handle cutting these big plastic pads? Would there be any risk of kick back? I think the pads weigh from 20 to 70 lbs. My understanding is that a Plainer will make them thinner but not fix any bow in the surface, but are somewhat automatically fed, while a Jointer is simpler and will be all hand fed, but will cut out any bow in the pads in addition to making them thinner.

What What should I look for in a machine? I'm used to building spare parts so I'm inclined to look for old American Iron. I suspect that both would be fairly loud and will require some level of debris removal. Our old machine just pushed all the shavings to the floor where they would be swept up between shifts (and it made a lot of shavings).
 
Carbide will be your friend, also I would not want to run one over a jointer.

I hate to say it, but a new grizzly with carbide head may be the cheapest option.

You can find a 30" top and bottom if you want to do both sides, but i still don't recommend planing plywood.

Older planers are probably better, but you can easily wrap up some money.




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There are combination jointer/planers (mine is a festool) which turn out to be a way to get a jointer that is really wide (16" 20" that sort of width) Not sure how "rubber" will behave on a jointer however...

edit: i mistyped it's actually a felder
 
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Just how "flat" do these have to be? Does the bottom have to be flat also? Does the pad need to end up with uniform thickness?

Need to answer these questions to pick one machine over the other.

But I'm thinking a cnc router might be the best bet, using a facing head. Wouldn't need to be really heavy or stout, that's a pretty light cut. If you need parallel faces, just flip and repeat. Neither a planer nor a jointer can do that alone, need both.
 
Flatness and parallelism would depend on the customers application, but anywhere from +/- .010 to +/-.050. The dies will flex a little, but it's best that they don't. In most cases, the bottom will be flat and we would just need to cut the top to be parallel to it, but we have run into some that warped or deformed from excessive use, so we would cut the bottom first. The maple block is meant to mitigate most of the bowing. In cases where the pads are not glued to a block, they're advised to flip the pad around frequently so it gets even use top and bottom. It wears out faster, but doesn't bow as bad as if you did all the cutting on one side.

I'll add too, that our way of checking these things was seeing if it would rock (if it bows it'll always be convex on the bottom), and using a ruler to check thickness. So we're not talking about super high tolerances here.
 
If you need to eliminate rocking, the planer won't do that. But pushing something that wide across a jointer requires a lot of strength. I had a 24" Yates, and it was all I could do to joint 20" panels.

If you need any kind of parallelism, you'll need a planer too.

Forgot to ask, what kind of budget do you have? And would you have other uses for those machines?

I'm still thinking a cnc might be the way to go. Would do pretty much everything the planer & jointer can do, but without any exertion or risk.

Just my 2 cent, I've never cut polypropylene, only UHMW, which is pretty mild.
 
My biggest concern with a CNC router is that operator skill and maintenance would be higher. Typically these pads were cut by shop help. If we had other jobs to do on a router (which we might), it would be a possibility, but not for this one alone.

Budget would be $2000-6000, and it would take awhile to pay for itself. We used to charge $35-45 a pad (depending on how much material needed to come off), and we used to see 10-15 pads a month on average. We would need to be able to do a pad in 20 minutes or less to justify the time. It obviously was not a cash-cow job, just a service offered, but one with a narrow profit margin. My hope is that a plainer/jointer would still keep the operator skill level down, but speed up the process.

I'm thinking now that a 24" Plainer would be the best option. We have some other options to fix a severely bowed pad, or we could turn them down. Honestly they only get that bad due to over-use anyway and we can't save them all.
 
Personally i would try to fix the old machine if that process worked well. 6 grand would go a long way towards a repair.
Running 20" plastic over a jointer sounds terrifying! Imagine leaning over a 20" wide piece and having it kick back!!

The cutting action between wood and plastic is entirely different, wood chips out soft plastic does not. There will also be a great amount of surface friction when sliding the piece over the table, you would need to use tremendous down force to keep that piece cutting.

Or it might work just fine. I would be interested to hear how a test piece performs.
 
That's pretty funny -
The last uses for Daniels style planers, was to surface the maple backer blocks for clicker presses in the shoe and fabric industries.
Many larger old shoe factories (remember those???) had a Daniels just to keep the blocks faced. I saw some auctions that included Daniels planers in the list, at least as late as the 1970's

A daniels was a very early style planer, in principle kind of a cross between a metal planer and a milling machine. It was sometimes mostly made of wood except the mechanical parts. The bed traveled. The vertical spindle had an insert (carbon steel in those days) cuttrerhead as wide as the bed. So it would make a wooden part dogged to the bed flat on the face as well as reduce the thickness.

I like the idea of a router, as Richard mentions, out-fitted with a spindle that could take a large dia (12"?) insert face mill, if possible.
The reason is your mention of metal in some of the blocks. The cost to constantly sharpen or change insert blades in a conventional planer, even a Shellix head could kill the profit in a few jobs. Changing them in a face mill with only a few inserts should be more cost efficient.

If you can find a short bed wide metal planer, i run that type of work on mine. My planer has a VFD on it, and the option of a very slow cone. Given the tolerances mentioned, your choice could be an archaic machine. You would have to slow the bed travel down commensurate with the cutter & spindle capability & crank the infeed up to whatever step-over is max. Or put a separate motor on the rail screw to step the router separately, signaled with an air or electric switch.
Mine is only 24" wide, and I only have a standard router head on it, so the largest cutter it can swing is about 2" dia. I use regular router bits, since i am doing the work for in-house applications and not usually for pay. Mine will step about 1" on auto, or i can stand there and crank it a couple inches per table reversal. With a router, it will cut coming and going.

smt
 
In this recent photo, i am using the planer-router combo to make 12:1 scarf joints on 16' long boards to make longer boards. This is for a personal construction project, but I used the method a lot for millwork, including wide redwood in the old days. It is also applicable to aircraft spars.

As you can see, without the wedge block sled, the planer could be facing wide non-metallic parts flat. It can be contrived to work rather rapidly.

What has happened to the photo manager - I don't seem to be able to add any?

smt
 
Personally i would try to fix the old machine if that process worked well. 6 grand would go a long way towards a repair.
Running 20" plastic over a jointer sounds terrifying! Imagine leaning over a 20" wide piece and having it kick back!!

The cutting action between wood and plastic is entirely different, wood chips out soft plastic does not. There will also be a great amount of surface friction when sliding the piece over the table, you would need to use tremendous down force to keep that piece cutting.

Or it might work just fine. I would be interested to hear how a test piece performs.
We opted not to fix the old machine because to took too long to surface a pad, compared to the cost of a replacement pad.
 
That's pretty funny -
The last uses for Daniels style planers, was to surface the maple backer blocks for clicker presses in the shoe and fabric industries.
Many larger old shoe factories (remember those???) had a Daniels just to keep the blocks faced. I saw some auctions that included Daniels planers in the list, at least as late as the 1970's

A daniels was a very early style planer, in principle kind of a cross between a metal planer and a milling machine. It was sometimes mostly made of wood except the mechanical parts. The bed traveled. The vertical spindle had an insert (carbon steel in those days) cuttrerhead as wide as the bed. So it would make a wooden part dogged to the bed flat on the face as well as reduce the thickness.

I like the idea of a router, as Richard mentions, out-fitted with a spindle that could take a large dia (12"?) insert face mill, if possible.
The reason is your mention of metal in some of the blocks. The cost to constantly sharpen or change insert blades in a conventional planer, even a Shellix head could kill the profit in a few jobs. Changing them in a face mill with only a few inserts should be more cost efficient.

If you can find a short bed wide metal planer, i run that type of work on mine. My planer has a VFD on it, and the option of a very slow cone. Given the tolerances mentioned, your choice could be an archaic machine. You would have to slow the bed travel down commensurate with the cutter & spindle capability & crank the infeed up to whatever step-over is max. Or put a separate motor on the rail screw to step the router separately, signaled with an air or electric switch.
Mine is only 24" wide, and I only have a standard router head on it, so the largest cutter it can swing is about 2" dia. I use regular router bits, since i am doing the work for in-house applications and not usually for pay. Mine will step about 1" on auto, or i can stand there and crank it a couple inches per table reversal. With a router, it will cut coming and going.

smt

I've never heard of a Daniels Planer, but it sounds similar to what we had. Ours was made in Denmark and was probably new in the 1950's or early 60's. Before we found that, we used an old worn out USMC Model C clicker-press that had all the mechanical parts removed and had a special resurfacing head mounted to a gear rack on the side of the swing arm. It took even longer to use than the Danish machine though.
 
They make similar things now for this stupid slab craze to flatten them for the guys that have no means to buy or run a facer.

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..never heard of a Daniels Planer, but it sounds similar to what we had

Not from your description.
A Daniels is one pass and done, under power feed.
No operator input except to set the work on the platen, lower the head, and trip the feed.

Your description sounded like what we called a broken arm drill, only outfitted with a router.
Actually, there were broken arm pattern routers, but they weren't call that.

Here's my metal planer, sometimes fitted out with a wood router.
As per previous note, making 12:1 scarf joints. This is only a 1" wide cutter as it was making 1" deep roughing passes at the starting end. The planer/router will take heavier cuts, but the wood will split.

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You can probably see that it can face anything laid on the table. Up to 24"w x 80"L on mine.

I do have a 30" wide facer (power fed wood jointer)
Don't think that is the way to go for your plastic app.
However, if you disagree, someone on here was selling one 20" wide within the past week.

If you can control for tramp metal & have a means to flatten the bottom, a regular wood planer should work. It might or might not be necessary to slow down the feed rate. An insert style cutter head would probably minimize maintenance. Some have visible striations, but the geometry is still within your flatness tolerance.

smt
 
I would pick up a used cnc router like a Shop Bot or similar. These usually have a single spindle, no tool changer, but they likely have an auto tool setter.
I'd write a parametric program so that the operator only enters the length and width of the pad and they'd use the auto setter to get the thickness, then press cycle start. It will probably be the upper end of your budget, but would be pretty slick long term. I would think that unless you use it for other things, it would be under your 20 min cycle time even with multiple passes.

If you happen to find a heavier machine, you could swap out spindles to one that would take a huge cutter,

I don't see an easy way to maintain parallelism with a jointer, a planer would be better, but it too may not be the easiest machine to turn a shop hand loose on without getting snipe etc.

One machine that may be worth looking for that is manual, if I recall some automotive cylinder head surfacers have a large insert flycutter on it. I think some of them are very large diameter, they have a nice fixture table to clamp heads to that you could pretty easily put the pads on. Doubt they have any that are 6ft long though...
 
My vote is for a 24" wood planer, helical head if possible.
A 24" jointer is a rare beast and not for the faint of heart, certainly not for "shop help".

To flatten a warped piece on a planer you just need a sled under the part and then shim up the centre, send it through until it is flat and then flip it and run it through on the now flat top side.
Easily doable with 3'-6' lengths, 1-6" thick.
Once you get set up with the planer it shouldn't take more than 10 minutes to complete the job on a single cutting pad. You will need a good dust collector for the chips/dust that will be created. You should be able to find an older planer and dust collector for your budget but it won't have a helical head. A 20" wide cut makes a lot of shavings.

Get a machine with a built in sharpener as that will save you a lot of time. I have a 20" SCM planer with built in sharpener and in about 5 to ten minutes I can have razor sharp blades. I can resharpen 8 or ten times and then have to reset the blades a little bit higher. It take about 30-40 minutes to change out the blades. Hitting any steel will be trouble and that is where a helical will shine, just swap out the nicked cutters and go again, inserts vary from $10 to $20 depending on the style. Not sure of the current pricing on a replacement helical but it should be in the $12-$1500 range for a 24" arbor, plus the swap out time.

If you have a machine shop then one option is to turn the planer head down and install shorter helical heads and stack them up to get your width. I have a 4" diameter x 4" long helical head for my shaper that I use all the time and I seem to recall there was an ad or two that I saw selling stacked heads for planers and jointers. If you opt to change to a helical then there is no need to get a planer with a sharpener. Don't go too old with the planer even if it is a good deal, get one with power table raise and lower and a good analog or digital height readout or ad one on if needed.

I think it would be prudent to get or make a small sample of a cutting pad and find someone with a helical planer so you can do a test cut to make sure that it cuts the plastic well. You were cutting it with a carbide rotary tool so it should work but does need a test before spending the cash.

An extra tip for you....I have a separate adjustable height outfield table on my planer that makes handling heavy pieces easy, it is just an old dental chair with the chair removed and a flat table added, works like a charm. I can post a pic if you or others want to see it in action.


Good luck,
Michael
 
Michael, last time I looked, a Shelix head for my SCM 20" planer was around $2700. I have the knife grinder also, so I declined. Knife grinder is great, had one for my 24" Yates jointer. I sold the Yates, as making just banjos now, nothing needs to be very wide, so I use a 6" Ppwermatic with a shelix head. That machine made me a fan of those heads, it can handle the most highly curly hard maple without tearout.

I also have a shelix shaper head, but that one left discernible and annoying scallops, about .005 deep, 1" apart. Otherwise a great cut. Talking to a dealer who sells a lot of shelix heads, he mentioned that Byrd did a better job on journal heads than heads for arbors. I indicated mine and got .005 TIR, which explained the scallops. Went down the rabbit hole - bored the head oversize, bushed it, and re-bored it correctly on my mill. A real PIA to hold the sucker, but I got it! Just had to shim 2 inserts w/ paper and scallops were eliminated! Maybe Byrd has it down better now, mine was bought over 10 yrs ago. But that would make me wary about stacking up a bunch of them on an arbor for a 24" planer head, plus it would almost certainly need to be balanced after assembly, Gotta be better to bite the bullet for a proper head, or just buy an import planer with a helical head.
 
Richard,
All good points and hopefully the OP will chime in with an update. I was just throwing out some ideas to try and get the job done within budget. A helical 24” planer may use up the budget and then some and without other work for such a large machine it may not work out too well when you consider the install costs plus a proper dust collector.
Perhaps with patience a suitable machine could be found at the right price.
 
I want to toss out a possible alternative. Wide-belt sander, like a Timesaver. That's assuming you can find a belt composition that will effectively work the plastic/rubber.
 








 
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