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USNR Multi trimmer

PostPosted: Sun Jul 18, 2010 1:16 pm
by A.McRae
Hi all,
We have installed a 21 saw USNR multi trimmer in our Drymill.
We have issues with poor finish on the timber and tearout on the corners.we are trimming 3x2 up to 12x2 Radiata pine.
The faster the lug speed the worse the finish gets, to the point of washboarding.
Saws are 22" dia 140tct doing 3316rpm at the arbor.
This machine originally came out of a greenmill operation.
Does anyone out there experiance the same issue?
My gut feeling is we need to spin the saws faster?How much I dont know?
Any correspondance would be much appreciated.
Regards,
A.McRae

Re: USNR Multi trimmer

PostPosted: Mon Jul 19, 2010 5:34 pm
by A.McRae
Sorry guys, RPM is incorrect! it is doing 1361rpm and 2609smpm

Re: USNR Multi trimmer

PostPosted: Tue Aug 17, 2010 11:41 pm
by wbsaws
Hi A. Mcrae
What is the feed speed of the lumber? This will determine your bite per tooth and how many teeth per minute you need to saw smoothly. Also, washboarding could indicate a lack of clearance angles on the sides( 3 degrees tangential & 1.5 degrees radial are standard ). Also, Top bevel angle,hook and the quality of the grind can all play a part. Use at least 240 to 320 grit diamond.The finer the better
Regards
Tony

Re: USNR Multi trimmer

PostPosted: Sun Aug 22, 2010 5:02 pm
by John M. McCullough
Alternate face bevel may help some also.

Re: USNR Multi trimmer

PostPosted: Thu Sep 23, 2010 12:18 pm
by A.McRae
Thanks guys,
We found that the hold down slippers were still set up for green mill application and the timing in the PLC was set incorrectly.lifting to early etc..
Dropped the height of saws to pass through the cut deeper also.Finish is now very good.