DIY Lap machine

**ALIEN!** · 09-07-2010, 11:54 PM

save a small fortune and build a sweet one yourself! Really easy build if you can weld and do proper fitup. You can find the motor for $100 or less on ebay. Imma build one myself as soon as I gots some fundage. Its pathetic that I cant afford to build this right this minute as cheap as it would cost. Really, this build would be under $200, take a morning to build. The diamond wheel costs more than it would to make the machine. I can't wait. Finally found a use for them old tires laying in the yard that came off a truck I don't have anymore, heh. Shit, man, sometimes you strike gold whilst surfing the interwebs.

I hope some of you put this to good use, I know I will:

http://www.hisglassworks.com/files/lapplans.pdf

**LTD** · 09-08-2010, 12:41 AM

that rocks

**dewalt** · 09-08-2010, 03:48 AM

Yep nice find

**Bo Diddles** · 09-08-2010, 04:53 AM

Wow, the timing of this thread is amazing... last week I turned my drill press upside down, attached the 8" wheel from my combo belt / disc sander, and put an angel food cake container around the shaft to catch the water. A bucket of water, a small fountain pump, and a 600 grit disc from His Glassworks, and I made me a geode!
I guess I'm going to have to take some pictures now...

**Bo Diddles** · 09-08-2010, 06:24 AM

Okay, here goes.... Snake, I hope you don't mind me completely taking over this thread, I can maybe get this moved to another thread if you'd rather....

This grinder was made from a small drill press I had attained from an auction house in the city I live for $17. I stole the wheel from my combo belt / disc sander, and ordered the lap disc to fit it. I already had the fountain pump which was $7 at a local surplus store. The angel food cake mould was also $7.
Here's what it looks like:

This is a pic of the wheel removed:

And here's the wheel with the shaft I rigged up - the shaft is almost perfect, but not quite, which makes the wheel wobble a bit. I would have thought that any wobble at all would make the grinder unusable, but it doesn't seem to cause much of a problem.

This is a pic of almost the exact same drill press... when I built the grinder, I tried to do it so I could put my drill press back together and still use it (I didn't really think this was going to work). I was at the same auction house last week and ironically I found my drill press's big brother - and got it for $17 as well!

And here's my first project with the grinder....

**Bo Diddles** · 09-08-2010, 06:28 AM

Oh yeah, I meant to mention that the geode was first cut with my shitty tile saw, then I ground it which took a long time, then I flame polished it. I'm going to order the rest of the discs I need to make this process faster. Now that I have a replacement drill press, I'll probably rebuild the whole grinder to make it less of a 'proof of concept' and more of a real grinder.

**Mecha** · 09-08-2010, 06:29 AM

Holy shit Brad. Nice build man...

Cool piece too.

**Bo Diddles** · 09-08-2010, 06:42 AM

Thanks man, I was kind of shocked when I was done and it had actually worked out like I wanted... sometimes stuff just comes together I guess...

**LTD** · 09-08-2010, 07:57 AM

Sweet!! Good job!!

**ALIEN!** · 09-08-2010, 09:32 AM

Nice work man! Gotta love home made tools!

**STROKER** · 09-08-2010, 09:50 AM

great link alien and brad that is for sure a nice homemade unit.

gotta make myself one of these.

**Uriel** · 09-08-2010, 02:29 PM

daymn, cant rep you brad,, uber awsome,, I got a stack of geodes I havent been able to cut.
Repped you in my head instead!

**LTD** · 09-08-2010, 03:18 PM

@~Diddles-
Which wheel did you get from HIS?

**Bo Diddles** · 09-08-2010, 03:32 PM

If you mean the lap disc, I got this one (600 grit).
The wheel that the lap disc attaches to was stolen from my combo belt / disc sander (for woodworking); I just took it off. This is a key part - if you (baylie or anyone) happens to find a place to buy that part, please post here... someday I've got to put my sander back together...

**LTD** · 09-08-2010, 04:45 PM

What brand sander is it? You could probably source one from the manufacturer? I would need that part as well. My cousin is a manager at HF so I was debating just having him grab a drill press from work.... just need to get the rest together. So many possibilities.....

**CoyleCondenser** · 09-08-2010, 05:20 PM

Macgyver style! I love it diddles.

Hey ALEIN!, you could modify that design so it uses grinding compound instead of a diamond wheel to save ca$h.

**menty666** · 09-08-2010, 06:09 PM

How do you keep the inverted drill press steady while you're using it? Clamp?

Awesome work....I'm going to have to start watching craigslist for a cheap drill press.

Wonder what I could find in a pawn shop..hmm.

**ALIEN!** · 09-08-2010, 08:01 PM

Originally Posted by CoyleCondenser

Macgyver style! I love it diddles.

Hey ALEIN!, you could modify that design so it uses grinding compound instead of a diamond wheel to save ca$h.

I was thinking about just ordering a replacement wheel for a regular factory unit and make a slurry grinder. From what Ive read, they're the way to go, on the other side I am wondering about what a pain it might be to switch grits for grinding/polishing. Then again a homebuild is so cheap, could make 2 or 3 dedicated grit machines for less than the price of 1 still.

**CoyleCondenser** · 09-09-2010, 05:49 AM

Oh no, it is a pain in the ass to switch grits, but unless you want to recover all the grit you can move from bigger to smaller sizes while only cleaning the hopper and the wheel. I must say that stuff is messy though......

**Bo Diddles** · 09-09-2010, 05:59 AM

Originally Posted by menty666

How do you keep the inverted drill press steady while you're using it? Clamp?

I took the bottom 'foot' off the bottom of the press and then bolted the bracket to the underside of my work bench. I still plan to make this into a better set up... this was kind of temporary to see if it would even work, and at that point I didn't want to do anything to the press that I couldn't undo later. It was more stable than I thought it would be, and I was really leaning on it at times.

What about a bench mounted woodworking sander? Maybe they rotate too fast... the beauty of the drill press is that you can change the belt placement to produce three different speeds.

I think the most important parts are the wheel and a shaft to fit the wheel. If you could find those parts, maybe with a belt wheel to go onto the shaft, the rest should be pretty easy to get together. No luck for me yet, but I haven't searched as much as I could...