How thick rough boards to start with before planing

[sams93]

Hi

So I am wanting to order some oak, I need 2.4m long, 150mm wide boards at 38mm thick, but the cost was extreme for PAR. (8ft x 6" x 1.5")

I am thinking of buying them rough sawn and then planing and thicknessing them at home, but I was wondering what a guide starting point should be for the rough sawn thickness to order, as I appreciate there is going to be twist/bow/cup that I am going to have to get out.

Thanks,

 

[Jameshow]

2" would be 1-7/8 sawn max leaving you 3/6 each side you plane off presuming you have a P/T

Others will be along with more experience.

 

[Bingy man]

All depends on what condition the boards are that you purchased and what equipment you have . I’m no expert but it’s a lot of work to get rough sawn to a decent finish. Yes the cost for par oak at 2.4 m is close to a £100.00 but how long will it take you to get a 20mm rough board to say 16 mm . Have a look at selco builders who carry oak par but 15-20 £ per meter + vat .

 

[Jacob]

Hi

So I am wanting to order some oak, I need 2.4m boards at 1.5" thick, but the cost was extreme for PAR.

I am thinking of buying them rough sawn and then planing and thicknessing them at home, but I was wondering what a guide starting point should be for the rough sawn thickness to order, as I appreciate there is going to be twist/bow/cup that I am going to have to get out.

Thanks,

Ordering 1.5" PAR means taking it from standard sawn size of two inches so are wasting a lot of wood. PAR is not a good way to buy timber - it'll be bent in a few days or so anyway.
Rule of thumb says you probably loose 1/4" in planing sawn stuff
But it depends on the lengths of the finished pieces. If long you will lose more thickness in getting them straight, and vice versa. This is why you cut them to length from cutting list before starting any planing.
You might have to adjust your finished design sizes depending on the stock and how the planing goes. Or if you are committed to the design sizes then order stock thick enough to cover all eventualities

 

[sams93]

I have a small planer and thicknesser. I appreciate that I will need extension tables to manage boards of this size.

I need 10 boards at 38mm thick, 150mm wide, and 2100mm long.

 

[Blackswanwood]

That’s a difficult question to answer as it depends on the Extent of any twist and cupping in the sawn board that you are starting with.

I’ve only used sawn boards at 27 and 54 mm thickness and would estimate that 3mm per face is lost as they go through the planer thicknesser.

 

[Jameshow]

What are you doing with the boards? If table or unit top, could you put a chamfer on the boards to disguise the thickness.

 

[sams93]

Making a super-king size bed - hence the need for them to be so long!

 

[D_W]

I have a small planer and thicknesser. I appreciate that I will need extension tables to manage boards of this size.

I need 10 boards at 38mm thick, 150mm wide, and 2100mm long.

I rarely use power tools, but I'm not above using them to size cheap lumber used for a painted bed frame (I have done this - your materials may be much nicer.

It's a lot easier to deal with big stuff like this putting the planer on the floor than it is to have it coming out pushing over outfeed, etc. this may be different if you're well kitted with outfeed tables, etc. I'm not - the whole rarely use them things. It's pretty easy to find something about the height of the tables with the planer on the floor and nothing falls much.

 

[Yojevol]

That's a really big ask for your small kit. I would recommend finding a timber supplier and go and discuss it with them. They will able to show you what their stock is like.
Seek advice from the members here for suppliers near you.
Brian

 

[Jameshow]

That's a really big ask for your small kit. I would recommend finding a timber supplier and go and discuss it with them. They will able to show you what their stock is like.
Seek advice from the members here for suppliers near you.
Brian

Agreed not worth the effort, time or wear and tear on a hobby machine.

 

[Bingy man]

I have a small planer and thicknesser. I appreciate that I will need extension tables to manage boards of this size.

I need 10 boards at 38mm thick, 150mm wide, and 2100mm long.

You may also need a set or 2 of spare blades for you planer as those are pretty hefty dimensions- I sent 200mm x 150 mm approx of reclaimed rough sawn 2.4 m long through my makita nb2012 and got reasonable results for a greenhouse base . I have a roller infeed and outfeed table and I struggled physically lifting the timber from in to outfeed .at 0.5 mm per pass it was a days work to prepare 4 pieces. It felt like I’d run a marathon.. good luck

 

[D_W]

(i made a comment about working the wood on the floor - I can't answer the comment about rough to finished, especially if you're using power tools, because it's going to be massively dependent on how straight the rough wood is.

The comment above about this being a little hard on portable tools is true. I'd still put the wear on the portable tools. Block out an hour or two to run the wood through, and if you don't have a facing planer, decide your cuts on the rough wood based on how you get the straightest wood out of it. If you're buying rough, buy straight timber and pay what it costs. You'll not regret it vs. buying common ungraded wood or something to save a few bucks - especially on a bed.

I've got a pail with a monster planer and he's got a pal who has a setup that makes his 20" DC580 planer look like a toy - it's fun to smash wood through their machines, but it still takes less time on the odd occasion that I do hardwood through a planer to let my poor little dewalt planer struggle through it than it does to load and unload to someone else's location.

I have beaten a dewalt 734 relentlessly about once a year with no mercy figuring that my days of babying power tools are over, and it has stalled and done all kinds of things once in a while when I set something wrong, and slowed down and chugged, and it's still going fine.)

 

[Jones]

Rough sawn will usually come in 3/4, inch, inch and a half and two inch. You won't get 38 mm from inch and a half and probably won't be offered inch and three quarters so it'll have to be from 2 inch stock. Ten 6x1 1/2 at 8 foot sounds like a lot of timber to make one very heavy bed, a redesign might save you a lot.

 

[Drifter2406]

Depending where you get it from a lot of it depends how they are dried in the first place and stored, the thicker they are the less the movement but I ordered 2.5" thick by 1500mm I think it was and the cupping was quite bad, these were wider than you are getting though, to get those flat I would have had to have taken off about 1/2 inch in total. Best to have a chat to your supplier.

 

[sawtooth-9]

To get 1 1/2 inch finished, you will probably need to start with 2 inch rough sawn.
Although your equipment is small, you can do this - just take a few more smaller cuts.
Take the warp and twist out on one side with the planer - about 1/2 mm passes.
Then thickness at about 1/2 - 1mm per pass.
2.1 M is not that long and I would not think you need any table extensions - just support the timber at the feed end.

 

[Just4Fun]

As others have said, suppliers typically sell in fixed thicknesses and the smallest standard thickness you can probably use is 2 inch / 50 mm.

The discussion about work and machine wear to get the material down to your required measurement is interesting because I often don't do it that way. Getting down from 50mm to 38mm is going to be a lot of work no matter how you do it. I avoid working to fixed dimensions as much as possible.

I use hand tools only. Very often I find the thickness of the piece is quite arbitrary and it doesn't much matter how thick a part is. So long as it is thick enough to be strong enough and any extra thickness doesn't adversely affect the looks, that is OK with me. For example, I am currently preparing some table aprons that are coming out thicker than I need but what does it matter? Nobody will see that unless they climb underneath the table, and I am far too lazy to plane a few mm off just to reach some pre-determined thickness.

I expect the same thing will apply to many parts of your bed, so I would reduce the work required and the wear on your machines by just removing enough material to get the boards flat, straight & smooth (enough). What harm would it do if your finished pieces were 44 mm instead of 38 mm? What harm would it do if the left side of your bed was 43 mm and the right side 39 mm?

Or am I the only lazy sod here?

 

[Jacob]

....

Or am I the only lazy sod here?

No not at all it's common sense. You have to work with what you've got and if necessary have changes of plan.

 

[Hornbeam]

How much thickness you loose will be very dependent upon the quality of the timber you buy, The longer the boards the more work you will need to do on the planer to get one side flat. On a 600mm length you might only lose 3mm but on 2.4m lengths you could easily lose 6mm +. Once straight you will lose another 3mm through the thicknesser. My general rule of thumb id a 1" nominal board will be 18 - 20mm once finished
Having just planed up 24 boards for some cottage style doors, I can confirm it is a lot of work and you will need a solid planer thicknesser

 

[Jacob]

How much thickness you loose will be very dependent upon the quality of the timber you buy, The longer the boards the more work you will need to do on the planer to get one side flat. On a 600mm length you might only lose 3mm but on 2.4m lengths you could easily lose 6mm +. Once straight you will lose another 3mm through the thicknesser. My general rule of thumb id a 1" nominal board will be 18 - 20mm once finished
Having just planed up 24 boards for some cottage style doors, I can confirm it is a lot of work and you will need a solid planer thicknesser

Yep
It's quite common to find boards which are unusable at full length, where the deviation is greater than the thickness. But a 10mm twist in a 3 metre board is reduced to 5mm if you cut it in half, and it may be fine for short lengths - typically noggins in stud frames, muntins in a door, etc