DTS400 problems

[teemacs]

Was the material that was being sanded at the dealer the actual surface of the MFT or something placed on the MFT?

Were you sanding pine or something else placed on the pine surface?

Seth

Hello, Seth. The surface the dealer tried was the MFT itself, and I'm sanding raw pine (a new bookshelf).

 

[teemacs]

If you can, take your workpiece to the dealer and try once more with your and another DTS.

Unfortunately, Oliver, the "workpiece" is a bookshelf, which currently occupies all the space in the garage that the car doesn't!

 

[grbmds]

The surface you are sanding probably makes no difference. What might be the difference, however, is that in the test on the MFT, the sanding was being done on a solid, firm surface (if I understand correctly that the test was done directly on the MFT and not with another piece on top of the MFT). What I have found is that, in some cases ,with both the ETS125 and the DTS400, the piece being sanded vibrates somewhat unless it is tightly clamped down on all sides. Since I use the VacSys and the pieces are clamped tightly, I have almost no problems sanding with these two sanders. So, if you are sanding a bookcase that is partially or completely assembled, the part being sanded might vibrate enough between supported areas that the sander would jump around. If the parts being sanded are not assembled, try clamping it more securely across the whole piece and see if the problem still persists. If so, I'd return it.

 

[semenza]

  What he said ^  Plus the MFT has holes which could be altering the suction / air flow.  Also the MFT would be very flat and smooth. The pine may have some undulations causing added vibration. 

  Seth

 

[teemacs]

Again, thank you all for comments and suggestions - much appreciated! I still have the sneaking suspicion that I'm doing something stupid, but I'm too stupid to see what it is! I shall experiment further this coming weekend and report.

 

[Tinker]

Is the piece you are sanding lying flat on the surface of your bench? or does the piece have a bit of cup, twist or warp to it?  An earlier poster suggested clamping the piece to the table you are working over.  Did you try that?
Tinker

 

[grbmds]

Again, thank you all for comments and suggestions - much appreciated! I still have the sneaking suspicion that I'm doing something stupid, but I'm too stupid to see what it is! I shall experiment further this coming weekend and report.

[member=8210]teemacs[/member] Not stupid at all. If you haven't already, try clamping it firmly if you can do that and see if that makes difference. I'd say that, if it doesn't make a difference, take the sander back. There is something else wrong. Since it's not clear whether the piece is already assembled or not, I'd just say that finish sanding a piece like a bookcase that is already assembled would be a challenge with any sander and the DTS400 would like act just like you indicated since there would probably be spots that aren't supported firmly. Not trying to tell you something you already know but, if the piece i already assembled, on the next project try sanding the parts before assembly. It's such easier. If you already do this, didn't mean to suggest the obvious, but I didn't see that this information was part of your post.

 

[Cheese]

FWIW...I always clamp single items or even complete assemblies solidly to the bench for sanding chores, otherwise you just chase them around.

If you do go back to the dealer, bring a sample of the wood that you're having a difficult time with. That way you can compare apples to apples. Also, test drive the dealer's DTS 400 on your wood sample and you can compare the 2 sanders to each other and make sure the 2 sanders are using the same grit of sandpaper.

 

[teemacs]

So I had a go today - and the problem is the workpiece itself. I tried the DTS400 on a piece of the shelf wood on the bench, and while exhibiting a bit more "wanderlust" than my other sanders, three would be no problem living with that. However, on the bookshelf, it went slightly mad. I've never encountered anything like this before - the shelf seems pretty flat and, as the bookshelf is double-sided with a  common 18mm board as backing for both and the shelves fitted into it with housing joints, I would have thought that the shelves would be immune to vibration.

However, lesson learned - Festool, I take it all back. Well, nearly all. I usually sand the finished article and I've never had this problem before, so why is this sander so sensitive? And why should it be? 

 

[Grakat]

Are you getting a minor vibration in the bookshelf which is then transmitting back into the base of the sander?

Is there an option to fit a softer base pad to the DTS400. I don't own one but I am considering one. I currently have a cordless Ryobi I could use to vibrate concrete.

 

[grbmds]

You could try the softer pad, but I doubt that would change anything and I believe the soft pad would likely result in some accidental rounding of edges and other undesirables. I don't know about others, but I found that, when I'm sanding something that is supposed to be flat in the end, the hardest pad available is the best choice.

Don't know why the DTS400 is a little more prone to vibrate when the piece being sanded isn't firmly supported, but the ETS125 seems to be more likely to do that for me also. I have always believed that it is a combination of the height of the sander and the fact that these sanders are vey light. When the pad is tipped just a tiny amount (not noticeable), then the sanders seem to vibrate. However, after using my ETS125 more, I found that I get much less of that, so it may just be getting used to the sander. Every sander (including those of other manufacturers) seems to have its own quirks.

 

[AlexThePalex]

There is only one pad for the DTS, no choice.

 

[Tinker]

You could try the softer pad, but I doubt that would change anything and I believe the soft pad would likely result in some accidental rounding of edges and other undesirables. I don't know about others, but I found that, when I'm sanding something that is supposed to be flat in the end, the hardest pad available is the best choice.

Don't know why the DTS400 is a little more prone to vibrate when the piece being sanded isn't firmly supported, but the ETS125 seems to be more likely to do that for me also. I have always believed that it is a combination of the height of the sander and the fact that these sanders are vey light. When the pad is tipped just a tiny amount (not noticeable), then the sanders seem to vibrate. However, after using my ETS125 more, I found that I get much less of that, so it may just be getting used to the sander. Every sander (including those of other manufacturers) seems to have its own quirks.

There is only one pad for the DTS, no choice.

I was gong to make the same comment as [member=19734]grbmds[/member].  I don't have the DTS, but I have found a problem with trying to sand flat surfaces with a soft pad on my RO 150.  When I changed to the hard pad, I was able to keep flat over even large areas.
Tinker