Click here for a PRINTABLE version of the above blueprint.
I like Sanding Backup Pads (mandrels) that are thin, low profile and HARD. I add (attach) firm or soft foam interface pads to make them softer as needed.
I don't like thicker pads. Low profile pads are better at getting into the tight space between headstock and bowl.
I started making my own Sanding Backup Pads a couple of years ago when the price on commercially available ones went to $12. Way to much! I now just replace the velcro on my big collection of DIY sanding backup pads as needed. See Repair Worn Out Velcro below.
I make my backup pads out of 1/4" plywood and 1/4" flat head bolts.
I ALWAYS use a interface pad because it allows me to quickly switch between sandpaper grits. I have one FIRM and SOFT interface pad for each grit. See my Handy Sandpaper blog entry.
1. Gripping the threaded part of the bolt in a drill chuck is not a problem. It works just fine.
2. If you are using interface pads to adjust the softness of pad then you don’t need and really don’t want a thick back up pad with lots of flex/foam.
Make Your Own
I make backup pads for 2" and 3" sandpaper.
I like my backup pads to be a little smaller than the interface pads. Thus, I really make 1-7/8" and 2-7/8" backup pads.
I layout 2" and 3" backup pads. They end up being 1/8" smaller after truing them up on the lathe and sanding the edges smooth.
Note: I normally make 6 new backup pads at a time. I keep a bin of new ones and worn out ones. The worn out ones need new velcro. I replace the Velcro when I run out of new ones. See Repair Worn Out Velcro below.
I layout 2" and 3" backup pads on good 1/4" plywood. Use a compass or template. See photo.
Drill a countersink hole for 1/4" flat head bolt. Then drill a 1/4" thru hole. See photo.
The countersink in the photo is a cheap and very common Vermont American one.
Use what every you have to ROUGH cut the circle. Cut OUTSIDE of the line.
I use my small wood cutting bandsaw. See my Small Wood Bandsaw bog entry.
I use a FULLY THREADED 1/4" by 20 flat head bolt that is 1-3/4" long from local hardware
store. With a nut and washer.
The plywood will eventually just spin on the bolt if you don't put some 5 min epoxy in the joint. I put 5 min epoxy above the bolt head and below the nut to create a rock solid joint. See photo.
Turn the 1/4" plywood circle round on the lathe.
I use a drill chuck in the headstock with a 1/2" scrap of plywood jammed up against the backup pad on the tailstock side. See photo.
The 1/2" scrap of plywood prevents tears out. I turn it down to 1-7/8" or 2-7/8" on the first backup pad I make. Then, I use it over and over.
I use a 1/2" bowl gouge to turn the plywood round. Cut half way in from both sides to avoid tear out. Then use the 1/2" bowl gouge in scrapping mode to round the back side of the 1/4" plywood. See photo and my Blueprint.
I don't allow any sharp edges in my studio that can accidentally cut me. Thus, I sand the 1/4" plywood smooth with 120 grit sandpaper. Red Siasoft Sandpaper works good.
Purchase Hook Side Only Velcro
I purchase a 6" wide roll of Sew On "Hook Side Only" velcro from you guessed it. Amazon. See
I attach the velcro with 5 min epoxy. Sticky back velcro is to wimpy for me. It does not work.
Google "6" Sew On Hook and Loop Fastner Hook Side Only"
Note: I like HARD backup pads. This makes finding velcro cheap and easy. I DO NOT need to find velcro with a firm or soft foam backing. I add (attach) interface pads to make them softer as needed.
I cut out 2" or 3" circles of velcro with scissors. Cut OUTSIDE the line. It should end up
being a 1/4" oversize.
Remember, to ALWAYS use your wife's best sewing scissors in the shop! 🙂
Glue the velcro on with 5 min epoxy.
I spread the epoxy and plywood then clamp it in place with a scarp piece of plywood. Or glue up two at a time and clamp them back to back. See photo.
I mount the backup pad in the lathe with a drill chuck and trim the velcro down to match the
plywood size with a spindle gouge.
I use a scrap of plywood that is bigger than the velcro on the velcro side to backup the cut. The scrap is just jammed in place by the tailstock. See photo.
Repair Worn Out Velcro
Sooner or latter the velcro wears out and needs to be replaced.
Well, it wears out because I forget to put a piece of sandpaper on it before trying to sand with it. 😮 But, you are never going to do this!
When the velcro wears out, I remove it with a belt sander. See photo. Then I go thru the above process to glue on a new piece of velcro.
I have a big collection of DIY sanding backup pads. I keep a bin of backup pads with new velcro and a bin that are worn out. I replace the velcro in a big batch when the new velcro bin is empty.
Blue Flex Sanding Disks & Interface Pads
See my Blue Flex Sanding Disks blog entry for more information.
Mirka Autonet Sanding Disks & Interface Pads
See my Mirka Autonet Sandpaper blog entry for more information.
I like to use a low profile angle drill for my sanding on the lathe. See the bottom of my Blue Flex Sanding Disks blog entry.
Sanding Cheat Sheet
Check out my Sanding Cheat Sheet. It ties all of my sanding blog entries together. Wet Wood? Already Finished? Spindle Turning? Bowl or Hollow Form? Then use …