how do i stop sandpaper from loading up ?

[tunnels]

.

The grit in sand paper is bonded with a resin make coat so soaking it in acetone will only wake the grit fall off.[/QUOTE]

I first started using acetone to soak and clean sand paper in 1984/5 and still do the same thing to this day i have never ever had sand paper fall apart or the grit come off or any sand paper soften ever in all this time in all the differant coutries i have worked in and am still working in !!

[Herman]

Still, are we talking epoxy or polyester?

If epoxy, then the resin is still too fresh to sand. Try and heat it up a bit to get a better cure.

Use a very open sandpaper, like Mirka Abranet or Autonet, and a good dust extractor.

[jiggerpro]

I tried acetone yesterday and acetone destroyed the velcro backing of the the back of our orbital sanders so now they do not adhere to the sander .........

maybe we should switch to epoxy resin for our shop made putty .........

[Herman]

I once posted about using a lubricant (Mc Lube), sprayed on the disc, which prevented clogging of dust.
Although when we did this, we never had problems with adhesion, I still feel a bit hairy about it.

[tunnels]

So we can all live and learn !
The orbital sanders that we use are always the ones with clips each end and use just plain sand paper off the roll not velcro backed !!. even long boards with plain sand paper just lay a rag on the sand paper and pour a little acetone on the rag . A short time later pick up the long board and hit on the floor and all the crap falls off ! and blow dri with compressed air and away you go again .
Maybe my life is to simple for most !

[Landlubber]

...nup, Tunnels is right, we used to do that too with the acetone, never had any problems, but we certainly did not use velcro papers...too dear anyhow for production work.

[tunnels]

Long boarding is the only way to get a good fair and true job 4 guys ,long board 2.4 mtrs long ,40 grit sand paper, and spend 5 days sanding continuously . The designer could not believe how smooth and fair the boat was . When the plug was polished every line of reflection was dead straight . It sure showed in the finished boats and we had good reports from all the guys that sailed on the boats how good they were appearance and performance !.Have seen all manner of fancy gadget but never been able to match a good long board .Our sand paper used to clog because we sanded as soon as it was possible to get in and rough sand off the surplus fillers and undercoats etc etc , Then when the high build went on its then spend time going through the grades of papers !.Been there done that a few times .

[oops!]

the paper is loading due to using un waxed poly resin.

air unhibits the cure of resin.....so the very top layer is actually still wet.....thats why its sticky...some times even after a few days.

some of the guys are using a pva spray over the new glass or gelcoat. this will let the glass/gellcoat cure.
it acn then be washed off with soap and water.....then the paper will not load as bad.

however,,,,pva or not......when you get thru the first layer of uncured resin, parer loading is far less.

resin backed grinding discs can be thrown in acetone....that works.....but you canot just throw any sand paper in acetone...lol

someone posted above that a long board will produce a really good surface....yuppers.....but an 8 foot long board is a real pain to use, the two guys running the thing must be in perfect sync or they end up fighting them selves, and tuckering out in just a few minits!

i use a hand help 24 inch long by 6 inch wide long board for fairing flat surfaces.......works like a charm.

cheers
oops

[Frosty]

Has someone not yet invented a long board machine? Everytime I look at a Fedships 100 meter sides I think of the faring invovled.

I cant believe its still done with 2 guys and a railway sleeper with some 40 grit nailed on it standing on step ladders.

Perhaps its not!

[tunnels]

We always made long board with 3 mm ply ,20mm thick polystyrene, and 3mm ply all glued together ,do them in 2.4 mtr strips so can cut to what ever length you want and attach a balsa handle each end . Light and strong and easy to use for long periods of time can even use 5 mm foam if you need a bendy board just still a little stuff for places less rounded 4 mm 0r 5 mm depending the shpe of the round . The lighter the board the easyer to sand with for hours .