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I'm making a home made sander as most of you would have guessed from my recent threads, and know I'd like to know what grit sandpaper you use on your drum sander and why? Also I assume you use different grades for different jobs and wondered a sort of what and where

I have some 60 grit which I assumed would be fine for roughing out backs and sides before moving to say 120, and I thought I may get some 80 to rough out tops and finish those with 120 too.

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Formerly JJH

I learn more from my mistakes than my successes

John buddy I use 80 grit for hardwoods and 120 for spruce/WRC and sometimes hardwoods when I am too lazy to change the paper and the paper is near the end of it's life anyway.... I wouldn't recommend 120 for hardwoods - just telling you about my reality here....

What I like to use is 80 grit for hardwoods and 100 grit for spruce.
Then final thickeness with scraper, hand sanding up to 180 grit before it goes to the brace fitting stuff.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Mine came with a big box of 80 and that's all I've ever used. I use a safe-t-plane for removing significant stock and use the drum sander to creep up on the last bit. Then I hand sand or scrape. Sometimes I think 100 or 120 would be good, but I bet it slugs up or burns pretty easily. I probably just need to get better at sharpening my scraper.

Mike

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Mike Lindstrom

A drum sander isn't a finish sander . Any thickness sander will build up more heat with the finer grits. Once that happens you glaze over the sanding surface of the paper. I now have a belt sander for this but I had a 2 drum thickness sander I would do a batch of tops and backs I would use 36 on the first drum then 60 on the back to start as this can hog down plated pretty fast. Keep in mind that you don't want to feel the piece heating up . The heat should be in the dust.
When I was .025 to finish I would swap to 60 front and 80 rear and finish off to the desired thickness. I stopped to within .005 to allow me finish sanding. The key to this is to match the feedrate to the cut rate of the paper. Once you feel heat building in your work cut back the amount of cut and increase feed speed .

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

60 or 80 to hog stuff down. 120 to finish it with very careful raising of feeder so just taking little off and taking out big sand marks at that stage. Since build in batches, doing plates, braces, finger boards etc. is a long full day at the sander. I can tell because end of day my back and legs are wasted.

I have always used 80 grit only. Thinking, as John said, that a thickness sander is not a finish sander. Works fine for both hardwood and softwood for me.

Chuck

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I just use 80 grit, but it leaves deep scratches in softwoods. I leave .010" at least to scrape or sand them away.
Thickness sanding "tip of the day"... I have found I get a much better finish & less heat buildup if I pass the workpiece though without raising the table, about every third pass. This is especially important when you are getting near your target thickness. Probably not necessary with the big dual drum manufactured units, but it really helps with my shop built sander.
Most people expect too much from a thickness sander... take really light cuts & be patient.
I use a safety planer to hog off the bulk on oily woods like cocobolo. Saves a lot of sandpaper.

80 grit is most commom here as well , dont try and jump more than 2 grits at a time IE 80 to 120 ok 60 to 120 not good , 120 wont take out all scratches from 60 g. Small scratches will show up in finish .

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Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
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Never met a STRONG person who had an EASY past !
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I know an abrasive expert who says and this was for metal "you can never jump grits more than double" ie 120 to 240 max or 60 to 120 like i say this was for metals and this is the guy I intend to by my papers from, do they have to be cloth backed the abrasives?

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Formerly JJH

I learn more from my mistakes than my successes

"I have found I get a much better finish & less heat buildup if I pass the workpiece though without raising the table, about every third pass. This is especially important when you are getting near your target thickness."

Ditto.

Chuck

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I use 36-80-120 for hard woods, and 80-120-220 for softwoods.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

From what I have picked up cloth backed abrasives stand up much better with drum sanders. My drum turns at 1400 rpm and I don't think paper backed word stand up to the abuse very well.

_________________
The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Cloth Backed . Jwt is good on finer grits . Xwt is alot stiffer .

_________________
The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/