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larry merlau
07-07-2004, 9:10 AM
i have a delta 18-36 drum sander and ran some oak panels threw it with i believe 80 grit or 100 to get the panels close and then hand sanded with 120 then 150 saw no problems and felt none,, but the stain said i had plenty:eek: // it appears to be a combination of troubles. the first one is they appeared to have snipe on them although i couldnt feel it? also the other panel had major lines as though i had groves in it like a planer might do with a bad knife. any one got some answers as to what i need to do to correct the delta sander or my procedure. really didnt need to see that last night but i can resand and start over on the panels in question. thanks for the help :confused:

Bruce Page
07-07-2004, 1:19 PM
Larry,

I have one of the early Delta 18-36 drum sanders and have learned a few tricks. The DS does sometime snipe - see #'s 6 & 8. I suspect that the groove you are seeing is caused by some sap on the sanding strip. The sap or "load up" can be removed using an eraser or by carefully picking it off with a scribe.

Here are a few tips that I have learned about the machine:

1. After changing sanding belts, always re-check the belt tension after using the belt for 5-10 min. Often times, they will stretch and loosen up near the clips.

2. Occasionally blow off or otherwise clean the belt to keep it from loading up. I sanded some sapwood one time and had to actually pick off little chunks of crap from the belt.

3. After a little practice, you will be able to tell by the sound if you are taking too heavy of a cut . If you are in the middle of a cut and the machine sounds like it is starting to strain, just lower the table a half turn and let it continue on.

4. When you blow a belt - and you will, don’t panic, just quickly lower the table a couple of turns and kill the power. When you do blow a belt, it will likely mar the board a little, so for that reason, I take light cuts when I’m getting close to the finish thickness. I also took a Sharpie and drew arrows by the crank to remind me of which direction is up & down. I still use those arrows every time I use the machine.

5. When setting the table height for the first cut, I lower the table and run the board under the drum, then I spin the drum by hand until it just touches the board, close up the top, hit the power and go.

6. My machine does snip a little. I always try to leave a few sacrificial inches on each end of the board just in case. If I don’t have any extra length to sacrifice, I will grab a couple of pieces of wood from the scrap pile and use them as a lead-in and follow-up boards. It’s really nice to have some help when doing this.

7. It is much easier to do one long board as opposed to several short ones. For that reason, I try to do all my TS cross-cutting after sanding.

8. If I do have to do several shorter boards, I set the table height as mentioned earlier and have each following board in direct contact with the previous board creating a "train". You will still be able to increase the cut, even when the drum is in contact with the board, but you will have to take smaller cuts. When I get all the boards in the "train" to the thickness that I want, and while everything is still moving along, I slowly lower the table a few turns and kill the power.

9. If you don't have the infeed & outfeed tables, bite the bullet and get them. They function well at reducing snipe and make sanding a lot less hectic - particulary on the shorter boards. I went a year before buying them and wish I had bought them when I bought the DS.

Chris Padilla
07-07-2004, 1:56 PM
Nice write-up, Bruce! There was an article in WOOD or AW not too long ago describing how to work with drum sanders. The gist was to go with light cuts with a drum sander...it isn't a planer after all! You'll need patience and practice. Gee, why does that sound familiar? :)

larry merlau
07-07-2004, 2:20 PM
[QUOTE=Bruce Page]Larry,

I have one of the early Delta 18-36 drum sanders and have learned a few tricks.////

thanks bruce// i havent had the blown belt yet and had used the eraser to clean the belt but will definatly employ your hints and tricks. thanks alot for your reply.

larry merlau
07-07-2004, 2:25 PM
Nice write-up, Bruce! There was an article in WOOD or AW not too long ago describing how to work with drum sanders. The gist was to go with light cuts with a drum sander...it isn't a planer after all! You'll need patience and practice. Gee, why does that sound familiar? :)


i think i had read that article bt this was sanded before then,, and i have chnaged my methods and even have acheat sheet on the machine to remind me of some of what i read and the wood has come out better since but i didnt see this coming till last night.. i hope i can resand and get them out, is that a possibillty bruce or do start over completly

Bruce Page
07-07-2004, 3:24 PM
i think i had read that article bt this was sanded before then,, and i have chnaged my methods and even have acheat sheet on the machine to remind me of some of what i read and the wood has come out better since but i didnt see this coming till last night.. i hope i can resand and get them out, is that a possibillty bruce or do start over completly
Larry, if you can see it but can't feel it, the snipe is usually only a few mil's deep, the snipe should sand out easily usuing your ROS.
Whether or not you have to start over depends on how deep the grooves are & how critical your thickness is. It's likely that the grooves aren't as deep as they look. I would use the ROS to try to sand out grooves. If you used an oil based stain, I wouldn't recommend the DS for fear of loading up the sanding strip even more and making things even worse.
If you're making raised panel doors and the panels end up too thin you could try shiming the backside of the panel to keep it from rattling.

Joseph N. Myers
07-07-2004, 4:12 PM
Larry,

I have an older Performax 16-32 but I would image that it basically the same as the Delta. On mine, the sanding drum is on top, the conveyor belt is on the bottom.
The difference between 80 and 100 grit is significant; it you can't really tell, maybe the belt is to worn to be effect. In my experience, the belt sander is equal to the next level of RO sanding, i.e., 100 = 120, 120 = 150, etc. So in your case, your should have gone to at least 120 (to get the 150 RO).

And I would use the erase (abrasive belt cleaner) every minute or so. On my Performax, the top lifts up revealing the sand paper so it is easy.

(I have a WoodMaster 18" 4in1 that has a sanding function. You can not lift the cover up easily, bolts, weight, etc., so I've held off using it. If I do, I've seen a "large" piece of something in different catalogs that you put thought the machine and it cleans the sand paper --- I might have to try it).

If you have a grove in the wood (raised from the wood) like a planer, it would be because the "grit" has been removed from the paper, maybe by hitting some metal like a nail. Turn the board around or shift it to the side and it should go away. If it were "sap" that you hit, it would leave a sap strip along the length of the wood. I've never had any luck removing the sap from the sand paper but have heard by soaking it in something, you can remove it. Because of that, I very rarely use it on pine or wood that contains sap.

Regards, Joe

Bob Reda
07-08-2004, 6:48 AM
You may also want to check to make sure your sanding belt is not overlapped.

Chris DeHut
07-09-2004, 5:11 PM
Hi Larry,

All the other advice is spot on good advice. The only thing I see missing is the #1 problem with "snipe" on our machine. It happens when feeding the stock in, and getting it going. The feed belt pulls the stock along fine, then as the leading edge of the stock hits the outboard presure roller, the stock will pause feeding for a moment. This will cause a line that looks like snipe and actually can't be felt in most cases. It is caused by the short dwell in feeding while the sanding drum continues to sand away the materal. In the metal working industry this would be similar to "Spark out", but since no sparks are caused with wood, not sure what to call it.

I can't say for sure when this occurs most often (feeding thick stock or thin stock, light or heavy, etc). I just know that I now watch for this closely and if needed, I push a little on the board to help feed it past that second roller. Once the stock is past it, all seems well.

Hope this helps you!

Chris DeHut
www.WoodworkingatHome.com