Help sanding rounded edges!

[rabtoy]

Hi there! Newbie woodworker here! I'm after some advise on the easiest way to sand round off edges inside a 60mm arch (think the top of a castle). Im using 19mm thick pine and have a tonne of these to sand! It doesnt need to be perfectly sanded but the pine is quite rough and theres lines from using the router. Thanks in advance for answering :)

[Chief Tiff]

Hi Rabtoy; and welcome to the forum.

If I'm reading you correctly then the best machine for this job is an oscillating spindle sander; like this one: https://www.carbatec.com.au/sanding-and-finishing/sanding-machines-and-accessories/spindle-sanders/oscillating-spindle-sander-single-carton-435x425x530-mm

A cheaper way though is to use a drum sander in a drill press, like this one: https://www.bunnings.com.au/haron-rotary-drum-sander_p6313841

Does this help?

[ian]

If rabtoy has a "tonne" of arches to sand -- and the arches are rough because they were cut with a router -- perhaps rabtoy's first step should be to make himself a new template and recut or trim all the arches using a spiral bit in his router.
Then sand with an oscillating spindle sander.

[woodPixel]

Any chance of a picture?

I do these for kids castle doorways and agree with Ian... a nice template with a spiral router bit does a fantastic job.

After that I made up a jig to fit into drill press that closely matched the diameter of the thing I wanted to sand. It is just a bolt attached to a large circle. The circle has a slot that a strip of sandpaper is inserted into (so there isn't a lump and its all flat). The table of the press is raised so it's quite flush with the circle (I should make an dust table and insert the circle slightly into it).

This lets me sand large diameter circular gaps very nicely. I found using a bobbin sander, even with the 50mm bobbin, that I would get little ridges and mis-sandings if my concentration wasnt focused of the wood hit a relative soft spot.

The reason for the excessive design is the client wanted doorways too, so the curvature needed to match. If the sanding was out, then it was obvious.

The jig didn't take much time to make.

[graham.murfett]

Hi Woodpixel
Any chance of a picture?