Gumming

A forum about crosscut saw filing
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sumnergeo
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Gumming

Post by sumnergeo » June 14th, 2019, 8:12 am

During our saw filing class last year we found that much of our filing involved cleaning out and deepening the gullets.

I helped Mike Siemsen (http://schoolofwood.com/) design and build a motorized gummer. We used a 1725 rpm motor with 1:1 belt drive to a fiber wheel. It certainly has saved a lot of filing - and files!
gummer1.jpg
gummer2.jpg
gummer3.jpg

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Jim_Thode
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Re: Gumming

Post by Jim_Thode » June 14th, 2019, 11:21 am

Cool!

It looks just like this one:
Gumming EC745 Fitting the Farm Saws - viewcontent.jpg

Arthur
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Re: Gumming

Post by Arthur » September 19th, 2019, 11:05 pm

Looks like a good way to extend the life of a blade.

Does the fiber wheel heat the blade significantly? Do the gullets end up “U” shaped, or can the original shape be duplicated?

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Jim_Thode
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Re: Gumming

Post by Jim_Thode » September 22nd, 2019, 9:36 pm

Arthur wroteCOLON
September 19th, 2019, 11:05 pm
Looks like a good way to extend the life of a blade.

Does the fiber wheel heat the blade significantly? Do the gullets end up “U” shaped, or can the original shape be duplicated?
Since the metal is relatively thin and it cuts fast the heat build up does not seem to be a problem. You can grind them to any shape you like, normally that would be U shaped.

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sumnergeo
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Re: Gumming

Post by sumnergeo » September 30th, 2019, 12:51 pm

It is possible to get the saw too hot to touch if you agressively remove material. We found that "easy does it" is a good approach so the steel doesn't get too hot.

I'll attach a photo of a foot-powered gummer from the Forest History Center in Grand Rapids, Minnesota.
image1.jpeg

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brianthehurdler
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Re: Gumming

Post by brianthehurdler » October 5th, 2019, 7:46 am

Could you elaborate on the wheel used? Is this just a standard cutting wheel for an angle-grinder? Looks like about 6mm / 1/4" thick?

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sumnergeo
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Re: Gumming

Post by sumnergeo » October 7th, 2019, 7:57 am

1/4 x 7 inch reinforced wheel. I would guess 60 grit. This is a straight wheel but depressed center should work. It doesn't have any info on the wheel. I wouldn't over think it.

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sumnergeo
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Re: Gumming

Post by sumnergeo » July 1st, 2021, 12:06 pm

Here is a short video of The Gummer in action on a Simonds No. 223. Only removing about 1/8 inch in the gullets. I use a die grinder to get the rakers closer to the desired shape.
gummer.MOV
(2.21 MiB) Downloaded 35 times

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