Hints and tips that some may not have heard of. #36: Thinning Thin Stock…

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Boys and Girls,
 
Sometimes the most obvious is not so, especially when you are a relatively newcomer to the world of woodworking.
 
Thicknessers (planers in Yankee speak) and drum sanders (drum sanders in Yankee speak) are renown to object to thin stock…
 
Get it up and "off" that in-built tabletop, for that shaving cut.
 
Fort the thicknesser, I made this static platform out of 18mm MDF,  laminated with some offcut laminex,
and padded out to 20mm using some walnut strip packers underneath,
with a couple of strips of pine on the ends keep it firmly on the tabletop.  I just have to remember to add 20mm on the depth gauge to my desired thickness.
 
I do not have faith in my built in depth gauge, so I go a tad thicker than my stock and lower till I take a shaving.  I then use a calliper to measure thickness, look at the gauge, 
get out my slide rule,
(must be solar powered as no battery required) to calculate the difference and adjust depth accordingly.
  
When it comes to the drum sander, I’ve made a number of sleds of different sizes.  
The thickness is immaterial, however, the thickness of the stop block on the end must be less than the stock you’re working on if you don’t want it reduced… not an issue on the first pass but consider repercussions if needed at a later date for thinner material.... etc.  With multiple sleds, chose the one with the appropriate backer… and the width of course.
I have a swag of sleds stored,

Nothing worse than having to make up a new sled and interrupting the project build flow.
 
Just don’t go by the inbuilt depth gauge

(they are seldom accurate) and an unfitted Wixey gauge,

even after 10 years, is bugga all useless.
Calibrate for the 1st pass by manually spinning the drum over the loaded sled,
then measure with calipers after each pass and I use the diagram on the machine,
for “micro adjustment”... 90° raises/lowers the drum by 0.4mm... lucky I don't read imperial.

****************************************  Late EDIT **********************************************

For those that tend to skip over the comments... Make sure you read SplinterGroup'scomments below... he bring up some great points/tips.

If your first cut is too short... Take the second cut from the longer end... LBD

Good tips Duck! They really should be called thinessers since that's what they do.

I almost exclusively used sleds for all my thining needs. Bonus is that any compression of the conveyor belt with narrow stock is eliminated with the large sled surface area. Also the sled area gets a good grip to the conveyor so no annoying slipping.

Helps reduce the snipe when the drum makes first contact and allows for shorter stock to pass through.

The fence only needs to be high enough to catch the stocks edge. My fence is at about 1/4" (could be lower) so when I'm sanding something thinner than 1/4", I will place a square of 3/16" masonite hardboard underneath to raise the stock up. 

Keeping an air hose handy is good to blow off the sled after each pass. This clears the sawdust (sandust?) away so the stock sits flush for the next pass.
Good points there Splinter...

I'm far from an expert, however, felt I should post something as I have been asked a few times by newbies of how the hell do you machine thin stock... usually talking 2-3mm.

If your first cut is too short... Take the second cut from the longer end... LBD

The thin stuff can be a bugger. Usually it's the leading edge that can make or break the process.

I've done 1/16" (1.5mm) by using a fence-less sled and using DS tape to hold the leading edge. The leading edge over the tape gets thinner so I consider that scrap when I lift off the wood (usually just slice it off with a box cutter, then pick the tape off the sled).
Interesting points here LBD. Thanks for sharing.

Main Street to the Mountains

Duck - that's a pretty good tip. Thank you.

A board with a stop.  Brilliant!

I am going to make one.


Petey

All terrific ideas that only come to those who have suffered with the insufficiencies of the machines we use.  A great lesson.  And the last photo in the group proves you know U from D!!!!!!   :-)



 PapaDave 
...  And the last photo in the group proves you know U from D!!!!!!   :-)

That's cause it's written in metric.

If your first cut is too short... Take the second cut from the longer end... LBD

I never thought about the compression of the conveyor before. Do you think that has anything to do with why if I place multiple narrow boards on the conveyor side by side, the ones closer to the motor side will bare the weight and the ones on the other side will sometimes slip or just not sand. I always see people do it on videos, but when I try it I never get it to work accurately. I've checked that the drum is parallel several times and it appears to be correct.

.................. John D....................


 awsum55 
..... 
I've checked that the drum is parallel several times and it appears to be correct.

There may be a tad difference between appears and actual...  I've never considered compression as my belt is not rubber, but more like sandpaper...
Either way, single feeding hasn't seem to make me age any quicker.

If your first cut is too short... Take the second cut from the longer end... LBD