Re: [Harp-L] Micro Mart Sprue Cutter

[Vern <jevern@xxxxxxx>]

A sprue is the channel by which liquid plastic enters the mold or through which air is vented as the mold fills.

There are no sprues on the surfaces of the SP20 comb that are visible or that make contact with the reedplates. For that reason, I don't understand what sprues you wish to remove.

I suspect that you are referring to the supports that run across the chambers.  They are there to keep the partitions from warping while the comb cools immediately after de-molding.  Although they serve no purpose after the comb has cooled, they do not affect the acoustical performance of the harp... so why bother removing them?

If you have a reason for removing the supoports, The MicroMark tool may or may not reach them. The blades may or may not be too thick.  You can't tell by looking at the picture.  If I wanted to remove the supports, I would saw them out with a fine-toothed jig saw blade Item # 15244.  A little scarring of the inside of the chamber won't be visible on the harp.

There is nothing that you could remove with that tool that would affect the appearance or function of the comb.  I would forget the whole thing and save my money and time.

I was amused by the MicroMark claim "Guaranteed for a lifetime of sprue cutting use." and their listing of replacement blades for $28 immediately below!   

Vern
  
On Jan 22, 2011, at 8:06 AM, Daniel Kowall wrote:

> I am considering buying a sprue cutter from Micro Mart,item # 15212 to cut the sprues in Special 20 combs.
> Any opinions on this tool or other recommendations.
> 
> Thanks
> 
> -- 
> Daniel Crash Kowall