Boom end clean up

[Nick J]

I'm lazy and interested in technology. That can be an expensive combination.

I currently have the boom pulled apart in preparation for painting and the current task at hand is cleaning up the boom ends. Most of the large easily accessible surfaces cleaned up easily with a sander. Now I'm left with the detail sections.




I've been looking for a media blaster and found a company that specializes in dry ice blasting. I called to request a quote and they said they didn't recommend dry ice blasting because itvwasnt abrasive enough, but they offer a laser cleaning service that may help. He hadn't worked on a sailboat before, so he was excited to try and potentially open up a new market.

Unfortunately it didn't work. The laser removed the paint week, but left the corrosion below want removed and would still require sanding. It was interesting to watch and might have some other applications on our boats. The dry ice blasting might be a good solution for bottom paint and could potentially be an envirinmently friendly alternative. I told him I'd give him a call next time we're out of the water if he wanted to give it a try.



So, now I'm back to hand work with a dremel. My experience with a few manufactures of wire wheels is horrible. I haven't found one that lasts longer than a few minutes. I went through a box of 50 cleaning and painting the transmission and ended up with tiny wires impeded in my cloths and exposed skin. Not fun. I didn't learn my lesson and tried again on the mast afew days ago with the same results. Does anyone have a recommendation for a more reliable wire wheel for a dremel?

 

[Prairie Schooner]

Hi Nick,

I admire how thoroughly you're going at this. Thanks for the great documentation.
Danger: Data Torrent Ahead

For fine scale detail sanding there are a bunch of tools used in metal finishing and jewelry that might work well for you.
Somewhat scattershot are:

There are variations you can do for a sanding mop with a mandrel and sand paper.
- https://www.instructables.com/Make-your-own-Sanding-Mop/


Smaller mandrels are available.

For a smaller mop to use in a flex shaft I take a one inch strip, fold it over itself in 1" laps as many times as I like and punch a hole in the middle. I don't cut radial strips like the mops show in the link. I don't even slice the folds. A few passes on something coarse will break the corners and regulate the edges.


You can use a split mandrel with a strip of sandpaper wound around it. This is great for honing holes or inside radii. It's not a precise hone, so I wouldn't use it for tight tolerance compression cylinders, but otherwise quite handy.

All these things can be scaled up or down for your needs.


Sanding sticks:
Get wooden, plastic, or ? shapes that are the negative form of what you want to sand and apply sandpaper. I've used rubber cement, spray mount, or double stick tape. Foam double stick can be useful if you want to add a little flex to the contact.
Shapes can be flats, dowels, complex curves, little 'fingers'.

This guy's 4 minute video is pretty much summed up in this screen shot. And I'd use something more robust than a glue stick. Slice them apart with a utility knife.


Shapes/tools like this are available commercially. I've made similar.

If you Want to use technology, you could 3D print out some custom shapes:

There have got to be digital files available out there.

But I've used these types of tools and like the glued on wood forms better.


You really don't even need to glue the sandpaper on. You can just tear/cut it to size and hold it on by hand.


There are shapes made of elastomers embedded with abrasive, available in different shapes. One long-running brand is Cratex.
- https://contenti.com/finishing-abrasives/arbors-n-mandrels
- https://contenti.com/finishing-abrasives/abrasives/mini-rotary-abrasives
Rio Grande is another jewelry supply house with even more selection, but you may need to start an account there.


A spiral mandrel is needed for some of them.



On Amazon look for "Dedeco Sunburst Radial Bristle Discs". Those spirals are useful, but then scroll down to "products related to this item". You'll find a bunch of other options. I picked Dedeco randomly. No particular brand recommendation implied.


I've used these abrasive buffing wheels, essentially scotchbrite, to good effect. They're available in different sizes and shapes.

https://www.amazon.com/dp/B07D7XJ5LQ?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_2

Continued in Part 2

 

[Prairie Schooner]

Data Torrent part 2

Scrapers can be quite effective. Just an old pocket knife works. For some extra control, hold it with one hand and push with the other thumb. More specialized is a triangular scraper, sometimes called a machinist scraper. For a proper edge you'll probably need to hone the faces of anything you buy at a moderate price.


For more precise scraping you can use gravers:





This page has some great tips, including some I want to try out:

35 Genius Sanding Tips You Need to Know

Save yourself some time and hassle during your next woodworking project with one of these genius sanding tips.

www.familyhandyman.com

I just sort of belched all this out. Some may need further explanation. Hopefully something will be of help.

Cheers,

Jeff