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View Full Version : Resawing v. Thickness Planing



orbb
10-12-2012, 09:21 AM
I need to reduce some 4/4 rough boards down to 5/8. I have done some with the thickness planer, which has worked, but the process is slow because of the need to take small bites. I still have a lot to do. I was contemplating resawing to 3/4 and then passing through the thickness planer to get smooth surfaces and down to size. However, I have read some issues about resawing releasing inner stresses, which may cause the boards to warp. Any thoughts on this?

Gold Rock
10-12-2012, 09:49 AM
You risk destablizing wood any time you machine it. If you take all the waste from your 4/4 boards in a single pass from just one side, you've maximized the risk of distortion. If you remove equal parts of the waste from both sides of the plank during resawing you've mitigated the risk as well as if you flip sides for each pass through the t.planer (which you are doing).

ARW123
10-12-2012, 12:19 PM
I have done both and offer the following:-

I have 3/4" to 1" sawn Oak boards that need to be finished to 1/2". I tried the resaw method and was disappointed with the level of saw wander - these 3/4" to 1" boards were resawn from larger boards (mind you these were 20' x 22" x 3" qtr sawn 5 y.o. air dried English Oak) - so much so that I lost 2 valuable planks as a result of the blade bowing and producing scooped boards. Now I'm not saying I was using top of the range resaw installations, but it was an approved piece of kit for the purpose. It did however set me thinking about the benifits of resawing on this scale ( I needed to split 4 of the larger boards to get 12 thinner ones and ended up with 9; that's some loss to my mind at over 40 per cu. ft....).

For my second batch I got the sawmill to resaw 23 ft 3 1/2" boards to 3/4" - they would have had the best equipment, they are not a small enterprise and specialise in Oak. Whilst the resultant boards should have been 3/4", the worst ranged between 1 1/8" and 3/4" in the same board - but I didn't lose any. My point being that to my mind you're not leaving much tolerance for blade waiver; but I'm no sawyer and there will be plenty on people lining up to shoot me down; but if it was my timber I wouldn't risk it - notwithstanding the internal tensions in the boards, which I am not qualified to comment on.

Now, I tend to cut the plank from the oversize board from the template really close to the line and run that through the thicknesser. I am running a new-ish Makita and the boards I shove through it are up to 20' long and just shy of 7" wide; yes it takes a bit of time to get from 7/8" or so to 1/2" and I weep at the pile of shavings on the floor, on the plus side I haven't lost a board through resawing and I have plenty of shavings to hot smoke the odd chicken or salmon fillet....

Dusty Yevsky
10-12-2012, 04:06 PM
'twer it me faced with the same job, I would resaw everytime. As Gold Rock pointed out removal of stock is what releases stresses, not the means to accomplish it. I've had good luck dealing wth this issue by resawing to an 1/8" of the desired thickness and leaving the boards to sit for two or three days and let the stresses "settle out". Then a trip to the jointer to remove any cup and then into the planer for the final thickness results in a stable flat board.

ARW123, if you're having problems with wander, you need to take a close look at the bandsaw setup. In my experience the bandsaw is the hardest shop tool to master but, regardless of brand, with enough fiddling and tweaking you should be able to get it to cut straight. Wander is usually an incorrect tension. Also, get the best blades you can afford. I put premium blades on my old Delta and can produce 1/16" veneers off an 8" board.

Ron Williamson
10-12-2012, 06:52 PM
Like everything else,it depends.
If you've got a good bandsaw,then go for it.
If your planer is capable,then it is a sure bet,even if it's a bit slow.

I'd plane it.
R

ARW123
10-13-2012, 03:03 AM
Dusty; wasn't a workshop bandsaw I was using in the 1st instance - it was one of the better "Woodmizers"; the boards were nearly 2ft wide !! In the 2nd instances a professional sawmill did the job. Rightly or wrongly I assumed they new how to set up their own equipment.

Mrleft8
10-13-2012, 09:15 AM
A 4/4 board rough sawn, won't yield any useful wood from resawing it down to 3/4" and then cleaning it up with the planer.... After you get your first clean face planed it'll already be down to 7/8" and your saw kerf'll eat up the remainder. I'd definitely just run it through the planer a few more times, flipping it each pass if you think it'll help, but there really shouldn't be that much tension wood in such a skinny board if it was properly dried.....

Boston
10-13-2012, 09:31 AM
I'd cheat and if the boards aren't to wide use a table saw instead of a band saw. Your not saving any cut offs anyway so whats the point. The table saw has a thicker blade so no wander and you can rip whatever you want off each side to keep things straight. Then make a pass or two on each side in the joiner, should clean up nicely. Or at least thats what I'd do if I was dealing with stock of say 6" or less.

Cheers
B

Desert Sailor
10-13-2012, 12:04 PM
How large (long, wide) are these boards? What species? What are you going to do with them--is there something special about 5/8", or could they be left a little thick? Is grain running in every direction, or is the stock of good quality?

The advice to rough mill, let them sit for a few days, then mill to final dimension is worth heeding, no matter how you dimension the stock.

But we're defaulting to big iron methods. If the boards are of reasonable length, hand planing is just as effective. It might take a little longer, but you'll get what you want, burn a few calories, and have a bunch of cool shavings on the floor to show for your work.

Chip Chester
10-13-2012, 03:06 PM
Get a couple of buddies with portable planers, set 'em up in the driveway, and make some chips. With four planers, you could be done in no time. Buy enough beer for your poor neighbors, too, when it's all done.

orbb
10-13-2012, 07:59 PM
How large (long, wide) are these boards? What species? What are you going to do with them--is there something special about 5/8", or could they be left a little thick? Is grain running in every direction, or is the stock of good quality?

The advice to rough mill, let them sit for a few days, then mill to final dimension is worth heeding, no matter how you dimension the stock.

But we're defaulting to big iron methods. If the boards are of reasonable length, hand planing is just as effective. It might take a little longer, but you'll get what you want, burn a few calories, and have a bunch of cool shavings on the floor to show for your work.

14 of the boards are 2 1/2 to 3 inches and 48 inches long. The others are 6 to 8 inches wide and 48 inches long. They are Ash. There is nothing special about 5/8 (aside from weight - Ash is heavy) and I am settling on 3/4. I planed one of the 2 1/2 - 3 inch boards down to 3/4 inches this afternoon, and it took around 15 minutes. I resawed all the rest in the next 15 minutes. Resawing won.

I am resawing on the table saw, so the wider boards are proving to more of a challenge. I am not opposed to hand planing, and actually prefer it. I have been planing one side flat so I can put them through the thickness planer and have multiple bags of shavings, which will be used to start the outdoor fire pit. I recently bought a used Bailey No 4 (http://forum.woodenboat.com/showthread.php?153384-quot-the-blade-is-pretty-sharp-only-with-very-very-small-knicks-quot) and after getting a new Hock iron, it works really well. Much fun.

I also think it is time to change out the planer knives - I am getting a lot of burning (although ash seems to burn no matter what you are doing).

Gib Etheridge
10-13-2012, 08:12 PM
If it takes 15 minutes to plane 1/4" off of a 4 foot 1x3 something is wrong with your planer. You should be able to do it in 4 or 5 passes in about 3 or 4 minutes max. I would put in some sharp knives.

If the ash is burning on the table saw as well you probably need to change to a sharp blade there too. Get a ripping blade. If it's burning more on one side than the other your fence is not set parallel to the blade.

Mrleft8
10-13-2012, 09:23 PM
Burning?!
Are you sure there are even any knives in the planer?

W Grabow
10-13-2012, 09:45 PM
My experience agrees with Dusty Yevsky. I recently resawed many feet of 1 1/4" African mahogany into 6mm thicknesses, then planed into smooth 5mm thicknesses. I initially had some problem with blade wander on the band saw until I got it set up correctly and got some practice. Little waste when you get it set properly.

orbb
10-13-2012, 10:11 PM
Burning?!
Are you sure there are even any knives in the planer?

Yes, knives are there. I am swapping them out tomorrow.

I have worked a fair amount with ash and it seems to burn with power tools. Saw, planers, drills - always some smoke. Remind me of an old Appalachian folk song:


Love is a precious thing I'm told
It burns just like West Virginia coal
But when the fire dies down it's cold
There ain't no ash will burn

Boston
10-14-2012, 10:05 AM
Not sure what kinda plainer you have but if you can, get the carbide blades, they're more up front, but if your going to be shaving that much wood they'll pay for themselves pretty quick.

Just a thought, although if you use the table saw trick as suggested, you'll save on planer blades as well.

orbb
10-14-2012, 07:52 PM
It was the planer blades. I swapped them out and worked like a charm. Filled a garbage can with shavings.

heimlaga
10-17-2012, 06:20 AM
To me this whole discussion seems to indicate slightly inderdimensioned machinery. You are removing 10mm and want both sides planed. When I do joinery work I normally resaw to finished thickness plus 5-10mm.
I usually face joint thereby loosing 2-5 mm and then it goes througt the thicknesser set to remove roundabout 3mm and then 2-3mm on a second pass. The second pass through the thicknesser gives me a chance to clean up tearout on one side by reversing the direction of the board. It also helps me set the thickness correctly beacuse this old model has no accurate scale but be measuring with calipers ofter the first pass and count the turns on the crank I can get it right on the second pass.

Just my thoughts.......

Boston
10-17-2012, 11:44 AM
thats one old machine, these days they have very good depth calibration as well as finish and rough settings. IE two speeds. Two passes is standard, the last taking maybe 1/64. The C&C machines are even more accurate.

If I've got more than a few passes to make, I'll rough it on a table saw, depending on width. But it sounds like he had some dull blades that weren't helping him much. Even so those blades will last longer if he doesn't overwork them.

Canoeyawl
10-17-2012, 11:53 AM
My old powermatic doesn't even flinch at an 1/8" cut in softwood. Although I wouldn't do it in this application.

orbb
10-17-2012, 02:04 PM
But it sounds like he had some dull blades that weren't helping him much. Even so those blades will last longer if he doesn't overwork them.

It was the blades. The machine is a Ridgid 13 inch bench planer. It's the only one I have had, but it seems like a pretty good unit. I planed a lot of white oak and ash with the old set of blades and I think that is what wore them down. They were pretty scuffed up when I took them out.

As for the depth gauges, I generally do that with a set of calipers. I set the planer for the first bite, and then turn the wheel that raises and lowers the cutter by 1/4 to 1/2 turns and run the boards through. It doesn't seem to bog the machine down by doing it that way.

heimlaga
10-17-2012, 03:19 PM
The most important thing is that you found out what was wrong. Planing away that amount of wood should be no problem at all when everything is in good order. I know very little about those new fancy machines but in your case I would also check the bearings if they have a bad sound. Worn bearings steal a lot of power.

Good luck.

Boston
10-17-2012, 10:31 PM
It was the blades. The machine is a Ridgid 13 inch bench planer. It's the only one I have had, but it seems like a pretty good unit. I planed a lot of white oak and ash with the old set of blades and I think that is what wore them down. They were pretty scuffed up when I took them out.

As for the depth gauges, I generally do that with a set of calipers. I set the planer for the first bite, and then turn the wheel that raises and lowers the cutter by 1/4 to 1/2 turns and run the boards through. It doesn't seem to bog the machine down by doing it that way.

That particular machine can need calibration from time to time, the mechanicals can get out of parallel with the table under it. there are four large actuators that operate on a chain drive that can be adjusted. If they're out of whack, it eats blades. That was my first planer and I've run thousands of bf through that thing.

Best of luck
B