Question concerning end-grain chopping board

[dance]

I have a question about milling stock for an end-grain chopping board I'm making. I'm ripping and cross cutting stock on my TS-200 with upgraded fence.

What's odd is that two or three of my eleven strips of stock are 1mm wider than all the rest - which (for an end-grain chopping board) makes tidying up post glue-up a nightmare because it can't just go through the thicknesser.

Why do you think I'm getting this result? The pieces seemed to be pushed up against the fence during cutting and the fence was locked down and didn't seem to move. Confusing. I understand if nobody can offer a solution for this!

Thanks

 

[Tom K]

When you passed the last pieces through your saw were you trimming an almost to size piece or were they almost to size remainders?

Not sure if I'm making it clear as mud :?
If you measure off the fence all the parts need to be off the same side of the blade.

 

[dance]

When you passed the last pieces through your saw were you trimming an almost to size piece or were they almost to size remainders?

Well first I was ripping strips off my timber so the stock began wide and then got narrower and narrower as I ripped off inches and turned the stock into strips (always using the same side of the blade!). I was then cross cutting - again cutting inches and using the fence.

 

[Tom K]

Well without being impolite do you think it expanded or that some one glued an extra 1mm on for a laugh? It has to be ripped wrong or thicknessed wrong wouldn't you think?
Your crosscutting only affects the height of the board.
It is all showing as endgrain isn't it?

 

[Peter Sefton]

Was the timber square ie 90 degrees, it sounds like an accuracy issue.

Cheers Peter

 

[Tom K]

Was the timber square ie 90 degrees, it sounds like an accuracy issue.

Cheers Peter

Agree thought it would have been a kerf discrepancy. What is the thickness of your blade?

 

[dance]

Blade thickness is 2.5mm. What I'm wondering is if when I got to the last piece (which was almost correctly dimensioned, due to the use of CBDesigner to minimise waste) I wonder if that was cross cut from the wrong face. I'd be certain that's what went wrong were it not for the fact there is more than one piece that's 1mm out. It IS the height of the board that's the problem because with it being end-grain (and yes, it is all end-grain facing up) when you look at it at table level, it undulates slightly. Could blade run out cause this? I guess if I used vernier calipers at both ends of the cross cut strips I could eliminate this as the problem as there would be a taper, right?

Thanks for your help.

 

[dance]

Was the timber square ie 90 degrees

Yes, I made a squaring cut on my SCMS and then checked with a square for true afterwards.

 

[Tom K]

So all of the components are exactly square i.e 25mm x 25mm but now you have glued all of the long grain there is a discrepancy in the flatness?
So minor differences in chopped lengths and the perfect flatness of your assembly area
wouldn't cover it ? Were you expecting to finish straight off the saw ?

 

[dance]

Hi Tommo, I am a bit surprised at the difference in the height amongst the pieces is all. I was expecting to finish off the saw, yes. Would you prefer I expected to use a shooting board or something else?
Thanks

 

[Tom K]

Dance, even if every block is perfectly cut to length and you assemble it on a granite surfacing plate you can still get creep with your adhesive on each joint.
I think it is usual practise to flatten the board after assembly. Block plane maybe?

 

[dance]

Thanks Tom. I'll try and source a decent block plane!

 

[Tom K]

Sod that I'd use a belt sander mate!

 

[Jacob]

...What's odd is that two or three of my eleven strips of stock are 1mm wider than all the rest - which (for an end-grain chopping board) makes tidying up post glue-up a nightmare because it can't just go through the thicknesser.

Why do you think I'm getting this result? ..

Not intending to be sarky - but basically you dunnit wrong.
This is normal; we all do it.
It's up to you to find out why, mainly by looking more closely at what you are doing, next time.

 

[dance]

Thanks Jacob. You're right. I guess what I was looking for was whether or not this is to be expected with the tolerances of the Axi TS-200 or if I should expect slightly better. I'll take a picture to illustrate what I mean. But yeah, you're right. Thing is I was being careful and there were two pairs of eyes on what I was doing....