Thinning resin walls?

Use a razor saw to cut the large slab into smaller pieces that are easier to sand. You can even saw them into almost-individual pieces, and then just file away the excess.

MAKE SURE you wear respiratory protection!

the doog wrote:

Use a razor saw to cut the large slab into smaller pieces that are easier to sand. You can even saw them into almost-individual pieces, and then just file away the excess.

There are no pour slabs. From what I can tell, the mould was designed such that in a perfect world, the top of the pour would be flush with the back side of the wall. In this imperfect world, the mould was sightly tilted, so the wall is uneven. The wall is intended to be about 1 mm (1/16") thick, but is in places 2 mm (1/8"). There is just nothing to saw.

DoC 

Hi,

I work in a shop where we master and cast with resin everyday.  Unfortunately, there really isn't much of a trick to fixing your problem.  If you have a belt sander it does go quicker/easier but sanding is really your only solution.

Rick

~Both Doog & Rick make good suggestions. A die grinder(cheap tool if you have a big air source) can be great for this, but like the belt sander,, you gotta be able to grasp the part from the front somehow. Cutting the fat part of the slab into sections, like Doog suggests is a good idea,(cut the unwanted material into a waffle pattern of destruction) and makes use of a smaller sanding/grinding disk work better. Cut down on the thick side to (near) where  you want the flat side, then cut/grind off those chunks and you should be close enough to sand away the rest on a block !

Good Luck !                 Indy

 ~~oh yeah, and wear at least a mask(respirator if you got one), gloves, eye shields,and AIRFLOW !

RickLawler wrote:

I work in a shop where we master and cast with resin everyday. Rick

~Interesting Rick, just what kind of work do you do?  I work in a shop also, where we master in (mostly SLA) resin and cast(mostly in various urethanes) everyday.

The tool the gentleman really needs here(we make our own in the shop) is a

Dremel disk sander Dremel doesn't sell

They DO sell the blank mandrels. we then attach a small cutting of ultrafine 3M Sanding Pad with C/A or hotglue, spin it in the flexshaft against our knife-tip to get it round, apply 150 or 220 grit sandpaper(adhesive-backed or with a shot of #77 spray on reg. paper) and cut the paper while spinning or rough-cut it with scissors and spin the disk edge against a sanding stick.    ~This tool can be held flat to the work to get VERY good results for the above kind of job. As You said Rick "sanding is about the only way" , but this is a great sanding tool for the job!  {look for this tool in an upcoming tips&tricks in FSM}

~Indy

Indy,

Some of the things I do - in the shop that I mentioned - is work for a scale modeling company.  My recent projects have included building four 1:16 scale shadow box dioramas to be placed in the Museum of the Marine Corps in Virginia.  I have also been working on two 1:1 scale Mars Rovers, one to be sent to an air & space museum and the other for a traveling exhibit, along with a number of smaller projects.

Also, the company recently purchased Custom Dioramics, a part of the old VLS corporation, and I have been refurbishing and remastering some of the line - as well as working on masters for new releases.

Rick

~Fantastic Rick ! Just completely FANTASTIC  sounding stuff, Thank you for the reply!

~Is it permitted for you to show the 1/16 scale shadowboxes? If so Im sure the guys here would love to see such a project. If not, I understand. The nature of my work,( in Rapid Prototyping) means there's very little in the way of specifiic jobs I am allowed  to reveal.

Let's see if I can sneak a photo....

The four exhibits represent important events in early Marine Corps history from 1800-1900 - the events are:  Cuzco Wells (Cuba/Spanish American War), Mexico City (Mexican American War), Bladensburg (War of 1812), and Harper's Ferry (American Civil War).

This is a WIP shot of the firehouse exterior for the Harper's Ferry scene as it stood around the end of August.   This is all I can show at the moment, I know you will understand.  Enjoy.

Another tool you might want to consider is a rasp.  A rasp is shaped like a bastard file but is much more coarse.  It will chew through wood very quickly.  You use the rasp to remove most of the excess material and then you finish by using a regular bastard file.  You can buy one at Home Depot or Lowes for around $10.00  Here's a nice picture of a rasp:

http://www.amazon.com/Nicholson-21860N-8-Inch-Hand-File/dp/B00002N5L7/ref=sr_1_4?ie=UTF8&s=industrial&qid=1255265912&sr=8-4

-Jesse 

Thanks for the suggestion. I'll go looking for rasps in the HW stores tomorrow.

DoC

Hey Doc-

             sanding it on a belt sander will get you close and save a lot of hand sanding. But holding a thin piece still on a belt sander is tough- 

I know this wil sound crazy- but I would use some two -sided tape. Wrap your thumb and fingertips in it. That way you have a much better hold, and better control of the part.

 Could you cut of the details and glue them to a sheet of styrene- then use spacers to re-establish the 1/16th thickness?

 Steve