Sanding a sculpted seat

[EitanS]

Hello,
Messing around with this sculpted seat/stool. I've used my angle grinder with a carbide disc to hog out the rough shape but need to refine and smooth it. My original (poor) plan was to refine with RO150, but it's way too large to manage these curves. Any opinions on if the interface pad can manage these curves? Or would it be too soft to level/fair the bumps left from uneven grinding? I know another option is the RO90 but that's not really in the budget right now. Hoping the wise FOG chorus can encourage that this is possible with either the soft or interface pad.
Thanks for any advice!
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[wow]

Have you considered the RO90? It seems to me that it would be perfect for what you are doing.

 

[Scott B.]

Interface on RO90 all day long.

125 not so much. You'd be edge riding. Waste of abrasive.

 

[jacko9]

RO90 for me, it's a great little machine.

 

[Scott B.]

This is a buddy of mine using the 90 on a log bench we made last summer. #rotex

 

[mouppe]

I used my RO125 with an interface pad to sand a carved seat. Turned out well for me. The 150 might well be too large, but if so I would go ahead and use it anyway and then come back with a hand plane to re-level the flat areas. This will leave your edges sharp again.

 

[sae]

You can get flap discs from 24 to 120 grit for a 6-7 bucks a piece at Home Depot.

If all else fails, it's not a huge piece, I'd just hand sand it.

 

[Wuffles]

Oooh, carbide disc? Off to find one of them now.

I've got a 2ft cubed lump of oak that's probably considerably dryer than the day I bought it that could make a lovely sculpted seat like that. And given I have no imagination I quite fancy copying what you're done there.

I am also (coincidentally) looking at an RO90. Would I need the interface pad too? What's that do, make the soft sanding pad even softer or something else.

Cheers.

Edit: Don't even know how to describe what the OP has attached to that grinder, all I seem to be able to find are flatish coarse sanding discs. Anyone any ideas?

 

[G3Trim]

I found this on woodcraft site wuffles, http://www.woodcraft.com/Product/149989/Holey-Galahad-See-Through-Disc-Round-Coarse-Blue-78-Arbor.aspx

 

[Scott B.]

Oooh, carbide disc? Off to find one of them now.

I've got a 2ft cubed lump of oak that's probably considerably dryer than the day I bought it that could make a lovely sculpted seat like that. And given I have no imagination I quite fancy copying what you're done there.

I am also (coincidentally) looking at an RO90. Would I need the interface pad too? What's that do, make the soft sanding pad even softer or something else.

Cheers.

Edit: Don't even know how to describe what the OP has attached to that grinder, all I seem to be able to find are flatish coarse sanding discs. Anyone any ideas?

The interface pad creates a large cushy section between the actual basepad and the abrasive, allowing conformity to odd shapes.

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[Wuffles]

Thanks both of you. I'll try and find something like that in the UK.

 

[Scott B.]

Thanks both of you. I'll try and find something like that in the UK.

Sure thing.

Just so as you know, the picture I posted is actually 2 interface pads. They are stackable for depth.

 

[Wuffles]

Cool. Found a set of discs from Saburr Tooth at a place in the UK, just need to verify whether I ought to be looking at coarse, or extra course.

 

[G3Trim]

Why not both wuffles, two is always better then one  [big grin].

 

[Wuffles]

I think if I were given something too coarse mounted to an angle grinder and a long enough power cord, I'd be bothering the Australians within a short period of time.

Seems the "red" disc pictured may be a medium 70 grit.

 

[EitanS]

I do have a some flap discs that will get the surface a little closer. My hope in using the Rotex w/ the interface is to maximize the flat surface of the disc to the curves of the seat. Using the grinder w/ the carbide disc or flap wheel still forces me to hold it at an angle. I think I already know the RO90 will be better, but will order the interface pad for the 150 and see what happens. OR, anyone close to Detroit have an RO90 I can borrow for a day?

 

[AlexThePalex]

If the RO150 was all I had at hand, I'd use it, the job's got to be finished, right?

OK, it's not an ideal situation, but if you keep it at an angle so only the outer edge of the pad touches the surface you can still do some useful sanding. I've worked like this on curvy pieces many times.

Just keep the sander moving.

 

[rizzoa13]

Scott, when you use the interface pads stacked like that it seems you have it on Rotex mode. That doesn't sand unevenly on the top and bottom points where the pad is touching first? I'd think putting it on the delta setting would be safer but I haven't tried it so let us know your opinion!

 

[Scott B.]

Scott, when you use the interface pads stacked like that it seems you have it on Rotex mode. That doesn't sand unevenly on the top and bottom points where the pad is touching first? I'd think putting it on the delta setting would be safer but I haven't tried it so let us know your opinion!

No, delta mode just vibrates with little effect through the interface pads.

Rotex is perfect. Keep in mind, the eccentric motion is very much softened by the stacked pads. In the picture I posted, the pads conform well into the crown. I was sanding nail filler in that picture.

Grit, as always comes into play.

 

[festoolviking]

Hi

Here is some shaping created with the RO 90 and RO 150. It's the legs on a coffe- table I finished the other day. I started with the RO150 with the normal pad and then moved on with the interface-pad. After that I continued with the RO90 with the interface-pad for the fine details. I will eventually make a separate post presenting this table. I just need som better lighting and photo-skills.  [smile]

https://www.dropbox.com/s/4sv7vurrexjwaj6/Foto%202015-02-07%2016%2038%2026.jpg?dl=0

Festoolviking