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previous: Jason Lollar No worries.I just posted the bo... -- 11/15/2002 9:33 PM View Thread

Re: Real newbie person guy man

11/15/2002 10:10 PM
Dr. Strangelove
Re: Real newbie person guy man
Jason Lollar wrote:
"I just posted the bobbin schematic pages, its kind of buried in my site and I think alot of people miss it including the working with forbon notes."
Your Forbon notes are good stuff and I'll add a few small notes (read: whining and complaining) of my own.  
There are many distributors for vulcanized fibre but only two US manufacturors.  
NVF sells vulcanized fibre trademarked as Forbon.  
LMC Plastics calls theirs "Dynos."  
I think the commercial Dynos is slightly denser and tougher than the equivalent Forbon. LMC claims to use a higher rag content in the mix.  
Both sell 1/16" thick 4'x8' sheets for between $60 and $80 in 1-sheet quantity, but the price drops rapidly after 4 sheet quantities. You can cut at least 500 bobbins from one 4x8 sheet, so the price break is academic at small production volumes.  
Cutting Forbon is easiest with a table saw. A 10" "thin kerf" blade with 60 teeth works well and leaves a nearly smooth cut. The cut edge needs minor finishing with #400, then #600 wet/dry sandpaper. An 80 or 100 tooth blade would be a little better.  
SK recommends reversing the saw blade, lowering the blade, and using Zero-clearance inserts around the it for the cleanest possible cut. Haven't tried it yet and can't find the right inserts for the table saw.  
I round off the square edges with a stationary sander.  
Drilling holes in Forbon without a drill guide jig is a vexation.  

Ali S Ooooo! Thanks guys! Helps me bunche... -- 11/15/2002 10:36 PM