How long do disposable thickness planers last in hardwood

[tibi]

Hello,

I have disposable HSS plane blades for my Makita thickness planer. I have already switched both sides and they got dull pretty quickly (as I was planing some old wood with former paint and traces of soil (which I have cleaned to the best of my ability before planing). I was searching online on how long should HSS knifes last in hardwood and I have found on another forum that it is normally acceptable to last 1 - 2 hours of constant use in hardwood. I was disheartened to pay 40-50 Eur for an hour of planing. I know that my wood was not in pristine condition, but getting blades dull in 1 hour seems to be a very short time.

I have made a jig to sharpen them and if that fails, I would need to buy sharpenable blades for 100 Eur / set instead.

How long on average do your blades last in hardwood before sharpening/replacing?

Thanks.

 

[MARK.B.]

I guess it would depend on the species of wood that you are using, some hard woods have Silica and other abrasives in them and will dull your blades on a planer or Table/Band saw quicker than you can say Jack Robinson . You could try taking less off in a single pass and see if that helps but i think that if your wood is dirty then you will just have to accept that your blades will dull quicker because of it.

 

[Terry - Somerset]

A Makita 1650W thicknesser has a feed rate of 8.5m per minute - 510m per hour. Other machines may have a different rate.

Assuming 3 passes through the thicknesser for each board = 170 metres thicknessed.

Assuming 300mm wide = 51 sq. m. As knives can be reversed = 102 sq. m.

At £50 a replacement set = 50p per sq. m.

I also find it annoying to replace expensive consumables - as an occasional user the cost seems disproportionately high compared to a typical wood purchase.

But this is a lot of wood planed unless running a business or a major project. If (say) 40mm thick you would need ~2 cu. m. at a total cost of £2k ++ depending on type, grade and sizes and supplier.

I hope you can find some cheaper blades, and/or the sharpening system works. But in the grand scheme of things it should not be a major issue.

 

[clogs]

if the wood is dirty I just give it a quick sand with a belt sander....paint will be a problem tho.....
if u do this kinda thing regular, perhaps a home made thickness/drum sandermight be the way to go.....
look at
this is on the short list of things to do for me....
Ive looked at the TERSA system to get carbide blades to upgrade/fit my big machine (400mm)
but they cost as much as a spiral head conversion....both custom made at around £1,500....ouch...
I was lucky to buy a Kitty blade sharpening machine....blades up to 250mm wide.....
they stopped making the machine years ago.....perhaps u could get lucky....
looks easy to make with some metalwork skills....
here in Crete we pay 7euro's to sharpen 2 blades x 250mm wide (single edge)......
I just made a few items in Oak dried from a prof lumber pile....door frame etc....
blades junk after less than an hour....and I did belt sand it to get rid of any grit first....
got almost to the finish size and then used the spare sharp set to finish off....
our sharpener is on the way to the shops so she drops em off and collects later........
it's just a bind fitting sharp blades.....sorry no easy answers.....

 

[clogs]

just had a look on utube for DIY plane blade sharpening machine.....
this is almost a direct copy of the KITTY machine....
thought u guy's might be interested....
def worth a look "tibi".....
hope this helps somebody....

 

[clogs]

oops a grey moment....lol....
utube.....

 

[tibi]

Thank you all, I have successfully managed to create a wooden jig for sharpening the blades.

I clamp it in the vice so that it overhangs the edge of the workbench and then place the blade in the groove. I rub the diamond stone/natural polishing stone/strop against the inclined face and after the bevel is done, then I turn it do the other side. Finally I turn it upside down and do the flat side.

It takes like 20-30 minutes to do both blades, both sides.

Maybe I will be able to sharpen them 5 times before they become too short to engage in the wood.

 

[kinverkid]

Any dirt left behind on used boards will blunt blades in minutes. You only need to miss a few areas when cleaning. I use almost exclusively used timber. If it is dirty I would usually take off the top 1mm with a scrub plane before putting it through my thicknesser. Otherwise, the two 200mm HSS blades and disposables on my Kity Bestcombi planer thicknesser will get through a few hundred metres at a guess before I re-sharpen or dispose them.

 

[tibi]

Any dirt left behind on used boards will blunt blades in minutes. You only need to miss a few areas when cleaning. I use almost exclusively used timber. If it is dirty I would usually take off the top 1mm with a scrub plane before putting it through my thicknesser. Otherwise, the two 200mm HSS blades and disposables on my Kity Bestcombi planer thicknesser will get through a few hundred metres at a guess before I re-sharpen or dispose them.

Thanks for the reply. I have only a few boards left for thicknessing from the dirty batch, so I will use the scrub plane and vacuum the surface. After that I should not be working with used wood anytime soon, so I can keep my blades sharp.

 

[Orraloon]

Dirt and old paint is hard on blades so any old wood I use first gets a clean up with an electric hand plane. The tungsten blades for these are quite cheap compared to thicknesser blades so I clean back to bare wood with that first then it can go in the thicknesser.
Regards
John

 

[Simon89]

Can you not get cheaper blades?

I think mine cost around £15 a set, once I have planed all faces of my reclaimed timber once I flip the blades over and carry on.

 

[tibi]

Can you not get cheaper blades?

I think mine cost around £15 a set, once I have planed all faces of my reclaimed timber once I flip the blades over and carry on.

I did not find any alternative non-original blades that would fit Makita 2012NB. I can either buy disposable blades (cheapest 34 Eur, sharpenable blades - cheapest 87 Eur or helical head - 500+ EUR). But as I have mentioned above, I have successfully sharpened disposable blades, so the problem is solved for the moment. I just need to figure out, how many sharpening can I take before blades become too short to engage in the wood.

 

[DBC]

I feel guilty sometimes when potential customers request reclaimed timber or even bring some down to the workshop to request furniture/joinery items be made from them. I have been talked into it a few times - one was a bar countertop in a British Legion and similar for kitchen and bathroom units I’d made and I even once make a tiny table for someone out of a piece of timber from an old shipwreck - but I typically just refuse this type of work.

For some reason over the past few years it is often old floorboards I am asked to use and the old tapered cut-clasp nails have often broken off at the thin end and remained in the middle of the timber and can be difficult to find even with a magnet. Well you do find them eventually when they hit a blade.

Everyone hates to turn work away but this thread has made me feel a bit better about turning this sort of thing down. It would be different it I was just milling this timber for my own use but how can you give an honest quote for proposed work when you don’t know how long you may spend removing old finishes, old fixings and so on not to mention the costs of changing/sharpening/replacing blades etc.