The Forestry Forum is sponsored in part by:

Draw for handbuilt acoustic guitar get your name in


Forestry Forum
Sponsored by:


TimberKing Sawmills



Toll Free 1-800-582-0470

LogRite Tools



Norwood Industries Inc.


Sawmill & Woodlot Magazine



Your source for Portable Sawmills, Edgers, Resaws, Sharpeners, Setters, Bandsaw Blades and Sawmill Parts

EZ Boardwalk Sawmills. More Saw For Less Money!

STIHLDealers.com sponsored by Northeast STIHL


Woodland Sawmills

Peterson Swingmills

 KASCO SharpTech WoodMaxx Blades

Turbosawmill

Sawmill Exchange

BRUTE FORCE Authorized Dealer

Woodshax Outdoor Vending Solutions

FARMA


Council Tool

Baker Products

ECHO-Bearcat



Author Topic: Cull Factor for Estimate Calculations  (Read 2249 times)

0 Members and 1 Guest are viewing this topic.

Offline Ga_Boy

  • Senior Member x2
  • *****
  • Posts: 1018
  • Age: 56
  • Location: Purlear, NC
  • Gender: Male
  • Been rode hard and hung up wet; more than once.
    • Share Post
Cull Factor for Estimate Calculations
« on: January 18, 2006, 10:27:10 AM »
Hello All,

I'm preparing an estimate for a job that calls for S4S material.

The job calls for Red Maple, finished to widths of:

12"
11.25"
9.25"
7.25"
5.5"
5"
1.5"

All material will be in 10' lenghts.  After I sawmill it and kiln dry it, I'll send it to a local mill shop for S4S finishing.

My question is what cull factor should I use?




Mark




10 Acers in the Blue Ridge Mountains

Offline beenthere

  • Senior Member x2
  • *****
  • Posts: 26964
  • Location: Southern Wisconsin, USA
  • Gender: Male
    • Share Post
Re: Cull Factor for Estimate Calculations
« Reply #1 on: January 18, 2006, 11:42:06 AM »
Not sure what you refer to as "cull".  I'd take 'cull' to mean wood volume removed because of holes, splits, or rot, etc.
  Usually thought of as a class of quality that is below any usable grade (of logs) and referred to as 'below grade' in lumber. 
Are you thinking of the loss in volume (bd. ft. ) as a result of edging and planing dry, rough-sawn lumber into S4S boards?

    :)
south central Wisconsin
 It may be that my sole purpose in life is simply to serve as a warning to others

Offline Ga_Boy

  • Senior Member x2
  • *****
  • Posts: 1018
  • Age: 56
  • Location: Purlear, NC
  • Gender: Male
  • Been rode hard and hung up wet; more than once.
    • Share Post
Re: Cull Factor for Estimate Calculations
« Reply #2 on: January 18, 2006, 12:59:59 PM »
OK let me define cull for my purpose.

How much material I should expect to loose due to excessive cupping, warping, twisting or some other reason that the baord can not be planed or edged in to its final dimension.

I have assumed that there will be a loss factor when I unpack the kiln charge and inspect the material that I will take to the planning mill for finishing.  This assumption is based on; to-date, in each charge there has always been a losse of material to the conditions mentioned above.  Usually not that great, but on this job I need to provide a specified amount of material in each of his defined dimensions.  I want to make sure I have enough to send to the mill for planning.  But, I do not want to kill my profit margine by sending too much. 

The whole order comes to a little over 2Mbf or a little over 3,000 linear feet.


Does this shead more light into my question?



Mark




10 Acers in the Blue Ridge Mountains

Offline Tom

  • In Memoriam
  • *
  • Posts: 25854
  • Age: 75
  • Location: Jacksonville, Florida
  • Gender: Male
    • Share Post
    • Toms Saw
Re: Cull Factor for Estimate Calculations
« Reply #3 on: January 18, 2006, 01:08:58 PM »
Ga-Boy,
I read once, long ago, that the expected degrade of hardwoods from air-drying to finishing was 60%.

That seems a little excessive to me and I think they weren't considering the salvagable material but rather the entire board.  Some people cull more than others.  I don't.  Age has me culling less, I think.  All the girls are pretty.  ;D

I wouldn't suggest that you use the 60% figure but I would suggest that you be prepared for a pretty good hit. :)
extinct

Offline beenthere

  • Senior Member x2
  • *****
  • Posts: 26964
  • Location: Southern Wisconsin, USA
  • Gender: Male
    • Share Post
Re: Cull Factor for Estimate Calculations
« Reply #4 on: January 18, 2006, 02:14:11 PM »
Ga_Boy
Thanks, as we have a better idea now what you are looking for.

Much depends on the grade of the lumber in the kiln, the amount of warp you get from drying (sticker spacing, top weight, drying conditions, etc).  Red maple may warp more as it likely didn't come from real straight trees (another variable) than some other species. I think I'd go with Tom's 60% and hopefully be on the safe side this time. Sounds like you don't have any numbers from previous kiln loads of red maple, but you will get some good experience from this one. If you do have some previous experience, or a pic. of the lumber stacked in the kiln, that would help. 
south central Wisconsin
 It may be that my sole purpose in life is simply to serve as a warning to others

Offline mur

  • Full Member
  • **
  • Posts: 94
  • Age: 68
  • Gender: Male
  • I need to edit my profile!
    • Share Post
Re: Cull Factor for Estimate Calculations
« Reply #5 on: January 18, 2006, 08:33:52 PM »
Hello Ga-Boy:

I have a German woodworker friend who uses the term - "fifty percent of your fibre will usually make your target - the other fifty percent will be fall-down of one sort or another."  So Tom's numbers are in the ball park. 
Don't dream it, be it.

Offline Ga_Boy

  • Senior Member x2
  • *****
  • Posts: 1018
  • Age: 56
  • Location: Purlear, NC
  • Gender: Male
  • Been rode hard and hung up wet; more than once.
    • Share Post
Re: Cull Factor for Estimate Calculations
« Reply #6 on: January 18, 2006, 09:01:12 PM »
This exercise is for a quote.  If I get the job, I'll buy 4Mbf of 1or 2 Maple logs, I want to make sure I have enough to send to the planning mill for surfacing.

What I do not send to the mill, I'll add to my inventory for sell as rough sawn....

If nothing else this is a good exercise in estimating for jobs....



10 Acers in the Blue Ridge Mountains

Offline Coon

  • Senior Member x2
  • *****
  • Posts: 2718
  • Age: 39
  • Location: Wynyard, Saskatchewan
  • Gender: Male
    • Share Post
Re: Cull Factor for Estimate Calculations
« Reply #7 on: January 26, 2006, 11:25:57 PM »
When sawing maple of any kind for kiln drying and to meet the highest grade possible I do suggest that you keep the side lumber separate from the rest of the lumber.  The side lumber tends to be the better grade lumber.  We also do this with white birch. 
 
So when buying your logs make DanG sure that you buy enough logs to get  atleast double of what your order is in side lumber.  The side lumber will also cup and twist less.  Now I do not know how straight or twisted your logs will be but I do know that when sawing other maples and white or red birch that a 10 foot length is hard to come by straight enough to meet  select, number 1, or number2 grades.

Brad.
Norwood Lumbermate 2000 w/Kohler,
Husqvarna, Stihl and, Jonsereds Saws

Offline FeltzE

  • Senior Member
  • ****
  • Posts: 544
  • Age: 56
  • Gender: Male
  • Fayetteville NC, Stop by and visit some time!
    • Share Post
    • Feltz's Sawmill
Re: Cull Factor for Estimate Calculations
« Reply #8 on: February 07, 2006, 07:02:07 AM »
Mark,

A local mill here in NC was making furniture blanks and other stuff for the no longer existant NC furniture manufactureres. In talking with the manager he noted a 25% loss of material from the saw to the finished product. At the time I was appalled but my experience is that it's probably even more unless you are starting with some perfect logs, but you will still loose some of the heart wood anyway.

Eric


Share via delicious Share via digg Share via facebook Share via linkedin Share via pinterest Share via reddit Share via stumble Share via tumblr Share via twitter

xx
are these cull trees?

Started by MILL BRANCH FARMS on Forestry and Logging

13 Replies
2826 Views
Last post March 05, 2013, 06:12:27 PM
by Ron Scott
xx
How do I choose which to cull?

Started by Dave_Fullmer on Ask The Forester

19 Replies
3553 Views
Last post December 13, 2003, 01:37:02 PM
by Tobacco Plug
xx
can you straighten cull lumber?

Started by mountaineer on Drying and Processing

7 Replies
4651 Views
Last post September 20, 2009, 10:45:58 AM
by solidwoods
xx
When buying tie logs do you cull

Started by just_sawing on Sawmills and Milling

10 Replies
2758 Views
Last post May 08, 2012, 09:05:48 AM
by NWP
 


Powered by EzPortal