Planer Thicknesser Keeps Cutting Tapers

[billycat82]

I have an Axminster AWEPT106 Planer Thicknesser and have been having problems getting the Planer to cut a flat surface without causing a taper or bow in the wood. I understand that there will always be some degree of taper but sometimes I'm ending up with a 1/2 inch difference between one end of the board and the other.

The Outfeed and Infeed tables are coplanar although there is some slight discrepency in the machine finish but the Planer has cut fine in the past.

Could blunt blades cause this kind of problem or is it more likely there is something wrong with my technique? The blades haven't been changed for about six months but up until recently I have only been using it for about an hour per week.

I have read different things about technique from some people saying to apply minimum pressure on the wood and simply guide the stock through whilst others have suggested applying pressure on the Outfeed table.

If I apply minimun pressure the wood seems to either vibrate or not cut at all unless I increase the depth of cut to over 1mm and then I have to apply a significant amount of pressure to prevent the piece from vibrating and rocking. However, I still end up with a taper or bow in the wood.

When I've tried applying pressure on the Outfeed table I end up with a huge taper at one end as all I'm doing is taking off wood at the end that goes through the Planer first and waiting for the flat finish to increase enough to reach the other end.

Any advice would be appreciated!

Cheers,
Mike

 

[Billy Flitch]

Hi Billy check the height of the blades and re set. Incorrect height often causes the piece to become bowed or wedge shaped.

 

[heimlaga]

I have once had problems much like yours and with sharpened knives and the outfeed table properly adjusted the problem disapperared. That is all i know.

 

[Chrispy]

From what you've said I think it's safe to say it's time to sharpen the knives, basically they are not removing as much wood as they should be so the bit that's left is lifting the work piece off the out feed table giving you your taper, try lowering the out feed table if you can, it should reduce the tapering but it wont improve the finish!

 

[andersonec]

Make sure the bolts holding the lower bed to the rising shaft are all tight, if any are loose this will cause the table to tilt.
Do not press down on the timber onto the out-feed table, this will cause the rear end to rise and cause sniping, if anything lift the timber slightly to keep it pressed onto the table under the blade, also if the holding down bolts are loose then pressing down will also exaservate the problem.

Andy

 

[John15]

Hi Billy,

After setting the height of cut are you locking the bottom table? If not the bottom table will slowly lower giving an unequal thickness.

John

 

[deema]

There are normally only two things to create the problem you hav

1. The knives are dull and as a consequence the cutting height has dropped and the knives are no longer just above the top of the plane of the out feed table.

2. The tables have moved and are no longer co planer along their length. Set the I feed table to exactly the same height as the out feed and check with a straight edge that they are actually co planer. With lifting tables they move...a lot in my experience!

 

[blackrodd]

By you're description of vibrating you're planer knives are well due a sharpen, but you can get an almost similar
symptom if the machine is clogged up with chippings, banging and vibrating
Also the tapered finish is quite possibly due to the cutters either being too low, (no cutting at the end of the workpiece),
Or too high, giving the tapered finish, It's also possible the two beds should be checked, corner to corner and length
ways for alignment, and they may need adjusting.
I suggest, you Check the cutters first.
Regards Rodders

 

[billycat82]

The problem now seems to be solved!

I changed and reset the blades as suggested and the old blades were nowhere near above the outfeed table!

Thanks everyone for the replies.

Mike