DIY: Make your thick shims thinner
 

There have been plenty of times where I have needed to finish a transmission and I have needed a shim that I did not have, or I needed a shim that was not available.

In these pictures I show a trick that I did using common DIN 988 shim that I ordered from mcmaster.com that allowed me to use a certain 5th gear as a 6th gear. There does not exist an off the shelf shim that is available for me to order that fits the dimensions that I needed. However, I was able to find some that had the correct ID, OD, but were a little bit too thick.

Using just my press, scrap pieces of wood, packing tape, sand paper, and a very smooth surface I was able to procure an appropriate sized shim fairly quickly. The particular project that I was working on required me to do something like this, however there have been times when this trick would have allowed me to finish a transmission and get it shipped out. Hopefully some of you may find this useful.


1. Shim that is too thick:
https://cimg4.ibsrv.net/gimg/honda-t...bd38a4e461.jpg


2. Place thick shim on block of wood in press
https://cimg5.ibsrv.net/gimg/honda-t...a6512507a2.jpg


3. Place block of steel on top of wood + shim.
https://cimg6.ibsrv.net/gimg/honda-t...b2ee7a92f9.jpg


4. Press down and create shim sized indentation into scrap block of wood. This can probably be done using a vise.
https://cimg6.ibsrv.net/gimg/honda-t...594a023bd0.jpg


https://cimg6.ibsrv.net/gimg/honda-t...1bb4bb97fc.jpg


5. Tape down sandpaper onto a smooth surface. You will not need this much. I was experimenting in this picture. You will most likely want to use sandpaper that is 180-400 grit.
https://cimg4.ibsrv.net/gimg/honda-t...71ff5642b2.jpg


6. You now have custom 'shim holders' that will hold the shim in place, thus allowing you to apply enough even pressure to sand this down quickly.
https://cimg0.ibsrv.net/gimg/honda-t...eec5d15fca.jpg


7. Now, just like Method Man in 'Gravel Pit'
https://www.youtube.com/watch?v=Of-lpfsBR8U#t=1m50s
'Back, back and forth and forth'
'Back, back and forth and forth'
https://cimg3.ibsrv.net/gimg/honda-t...0db8df87c9.jpg


8. Measure throughout the process until you have produced a shim that is in your desired thickness.
https://cimg6.ibsrv.net/gimg/honda-t...320a27d1c2.jpg

Re: DIY: Make your thick shims thinner
 

Update: You're absolutely going to want a higher quality sand paper. Otherwise you'll be spending most of your time removing worn sheets + spraying glass surface with rubbing alcohol to remove glue / adhesive residue from tape / scraping residue with razor, and then taping on a new sheet. I spent more time than I care to admit researching sandpaper options / brands. The conclusion that I reached was that the '3M Pro Grade Precision' sandpaper was the best option for me. I placed an order on line for a few 20-packs of the 9x11" sheets in various grits, but then a few weeks later I realized that home depot carries bulk packs (15 sheets) of this in every grit that I ordered, and for less.
https://www.homedepot.com/p/3M-Pro-G...P-15/205415971

I haven't used any of this yet for sanding down shims, but the sandpaper feels higher quality than what I got from Lowes.

Good luck.


https://cimg0.ibsrv.net/gimg/honda-t...925890ab1a.jpg