Lumber Question - Using Cupped Boards

[wcndave]

Just watched the Video again by Steve: he talks about getting rid of snipe.

My movement test is < 4mm, and I had thought I was getting this with short pieces.

As I said earlier I will have another try.

Maybe where I've seen others have more difficulty was with long and heavy timbers, where support cannot be done. Rollers at exact height tend to get pushed over by the board, so you have to put them slightly low.

Off for a play now!

 

[mailee]

Snipe really does depend on the machine. I used to have an Elu 1161 P/T and could guarantee I would get some snipe on most boards. To help with this I used to support the timber by pushing up lightly on the end of the timber exiting the machine, it did help. I now have a large dedicated thicknesser (Axminster TH 410) and get no snipe with this machine. :wink:

 

[rafezetter]

for removing the bad cups / twists etc - watch this vid - I found it a while ago and it talks of removing cup with minimal reduction of thickness - made a lot of sense to me.

https://www.youtube.com/watch?v=W-MyiEQhzuU

 

[RobinBHM]

Minimising snipe can be difficult to eliminate and some machines are more prone than others. And thin sections can suffer from bounce causing a snipe, depending on chipbreaker pressure

On a thicknesser snipe is more likely to be at the end than the start. If you can machine in longer lengths for multiple drawer sides that will reduce the amount of waste, although probably not possible on that timber! If you feed the pieces in a continuous run, ie backing up, that can reduce sniping.

 

[RogerBoyle]

I have an older 2001 Scheppach planer thicknesser hms260 its very rare that I get any snipe with it Most of the stuff I plane down though is no less than 18mm Its usually 23, 37 and 46 mm thick stock that I Thickness down to.

Roger

 

[wcndave]

So, finally did some planing of the 34mm boards, and first few were great, retained most of the thickness and was able to resaw a couple of smaller ones.

Then when edging one I was in the zone and only realised after a minute that I had tapered the board without ever getting a full pass on the edge.

One end had 1cm removed and the other none. Perhaps the board was concave along the edge?

The board is 18" and so shorter than both the beds.

I then decided to check setup again and found that although i'd aligned the beds (using spirit level), they were quite out, more so on one side.

Using my newer and better veritas straight edge, I went through the very difficult process of aligning. I am not sure about others, but on the scheppach you have to loosen 4 hard to reach bolts, lift the table to position and then tighten whilst lifting. Why there can't be levelling feet or some other simple mechanism I am not sure.

I did loosen only slightly, ant try with rubber mallet, for final adjustment, and then the act of tightening shifts the table.

So it was slight tighten of one bolt, then check the four positions (two on each table) with feeler gauge, and then slight tighten next one etc. also raising and lower the infeed each time after it was fairly tight to check the effect of moving the tables.

One side, one hour. Next side, thirty minutes.

Put everything back together, checking all the time.

Put fence on, and one table is square, other not.check again, have gap on one side that is quite significant!

After repeated checking each slight tighten of every nut i was pretty peeved... And that's where it is...

I also noted before it went out of alignment again, that with straight edge straight along table, i could not get a 0.05 feeler gauge under any of the four points which are extreme ends and the mouth.

However on a diagonal there were always gaps. Not sure how this can be, when it's straight across and along in all places!

Also on infeed on fence side I notice that a straight edge from end to mouth allows a 0.08 gauge under two thirds of it's length, and quite close to mouth.

Not sure if that's significant, and not much I can do about it anyway.

Some days can be very frustrating!