flat lap questions

[David Williams]

Hey Paul, Steinert will sell you those parts to build the HIS grinder. They are about $1300.00 though. I recently went ahead and bought the 24" Steinert flat lap which is probably on the water right now. Without pads it cost me four grand including crating and shipping to Hawaii. If I had to do it over again I probably would have gotten the SW machine. Its about the same price, but includes a complete set of disks. Which I think is the best deal around.

[Jack Bowman]

Paul,

Go to a local machine shop to have the plate made. Cast iron is great. Should be a few hundred.



Ron,

How thick is that bowl?



Jack

[Brian and Jenny Blanthorn]

Okay - still looking for a solution for bowl edges.

I looked at the flat lap plans on hisglassworks.com -- it is straight forward enough but I'm not sure where to get the 23.5" x 0.5" steel circle.

I'd also like to hear who has experience with one of these:

http://www.hisglassworks.com/pages/air658.html

and what your thoughts are.

Thanks,
Paul

Try n buy a second hand machine

I got my top cast in cast iron 36 " x2"

Brian

[Ron Coleman]

Paul,

Go to a local machine shop to have the plate made. Cast iron is great. Should be a few hundred.



Ron,

How thick is that bowl?



Jack

It's two layers of 1/4 inch float. The shallow angle really makes it look thick.

Ron

[The Hobbyist]

Ron, As usual, the bowls are beautiful. That big float bowl is part of my motivation in building a lap grinder. The vanilla bowl is new isn't it? I love 'em both. Got any more pictures that we haven't seen?

Paul, I bought a 24" x 1/2" steel plate at a local machine shop for $80. He just ordered it from his supplier. It is heavy, naturally, and quite flat. I'm building the grinder as per Ron Coleman's plans although they are not that different from HIS. The big difference is the final rpm of the disc. With grit, according to Ron, you need to spin it much slower than for diamonds.

I'm getting real close to having all the parts and will begin the actual construction very soon. I'll try to go slow enough to take some pictures and maybe even post a tutorial someday. I have managed to get most of the parts on eBay or through my local machine shop. (We did a nice trade, glass for bearings.) So far I have only spent about $150 but I already had a 1/2 hp motor. Since I'm a Hobbyist the goal is to build it cheaply.

Anybody got a spare sprocket laying around?...................Jim

[Ron Coleman]

The vanilla bowl is an old one from last fall. And yes, there are a ton of pictures you haven't seen. If I can get a spare minute I'll post one this evening. A little something different maybe.

Ron

[charlie]

Okay - still looking for a solution for bowl edges.

I looked at the flat lap plans on hisglassworks.com -- it is straight forward enough but I'm not sure where to get the 23.5" x 0.5" steel circle.

try talking to local machine shops. it has to be machined flat, and balanced. otherwise, it could be deadly.

I'd also like to hear who has experience with one of these:

http://www.hisglassworks.com/pages/air658.html

and what your thoughts are.

Thanks,
Paul

hope you have a LARGE compressor. there's an electric one out there that quite a few people on here have. fleshetti or some such is the name, but i forget the exact spelling.

[charlie]

Anybody got a spare sprocket laying around?...................Jim

bike stores (both motorcycle and bicycle) have boxes of them they take off used bikes.

[The Hobbyist]

Charlie, I need a heavy sprocket (#40, #50 or #60 chain) like the one Ron used to attach his shaft to the steel plate. I bought one on eBay that would have been perfect except the idiot seller mismeasured the bore. Apparently he couldn't tell 1 1/2" from 1 7/8". Here's a picture of it.

Jim

[charlie]

that really looks like a superbike m/c chain sprocket to me. my m/c has a shaft, so i haven't seen any chains in a long time, but the newer m/cs have enormous chains to get the power to the back wheel.

[scooter riegelsperger]

Boston Gear has every immaginable gear or sprocket. They are a little on the expensive side but they have always had that hard to find item when I needed it.

[Nikki ONeill]

Paul: Check Granite City and HIS for angle grinders. Felissati (Italiian), Flex (Ryobi), Alpha, and a very expensive one whose name I can't remember are options. Most are around 6 pounds, the Flex is 4+pounds. Some variable speed, all with water feed. Six pounds doesn't sound like much, but I bought Beth's Felissati and it's not light. If you get a pneumatic model, it'll be a lot lighter. A few people on the board posted last year that they had the Felissati, so I went with it. But evidently the bushings may need replacing at some point.

Have fun.
Nikki

[Paul Tarlow]

hope you have a LARGE compressor. there's an electric one out there that quite a few people on here have. fleshetti or some such is the name, but i forget the exact spelling.

I have a 7HP 80 gallon single stage quad cylinder Campbell Hausfeld that puts out 16.8 scfm @ 90 psi. Oooooh - it makes me shiver just saying it

The electric version is actually cheaper -- I was just thinking that water and air go together better than water and electricity. Seems like the air version would be more reliable.

- Paul

[Paul Tarlow]

Just curious what type of bowl edges you're after Paul. I don't remember if you have a wbs of not?

If you're after an edge like this bowl you need the flat lap grinder. I call this one a flat grind, very time consuming if you polish it to a mirror finish. It takes more than an hour of hard work to get this type of edge.

I have a small wbs.

The 1/2" float boal is exactly the kind of edge I want. I guess I just need to decide if I want to pay for it

What sequence of grits did you go through to get that edge?

Thanks,
Paul

[Ron Coleman]

Just curious what type of bowl edges you're after Paul. I don't remember if you have a wbs of not?

If you're after an edge like this bowl you need the flat lap grinder. I call this one a flat grind, very time consuming if you polish it to a mirror finish. It takes more than an hour of hard work to get this type of edge.

I have a small wbs.

The 1/2" float bowl is exactly the kind of edge I want. I guess I just need to decide if I want to pay for it

What sequence of grits did you go through to get that edge?

Thanks,
Paul

Rough grind is with 80 Grit, then 180, 400, 600 and then cerium. Pumice would help after the 600 and before the cerium.

This is all with silicon carbide grit and water drip. Diamonds would be nice but costly and you need lots of running water, which I don't have in my studio.

Looking at the specs for the air grinder, it would take all the air your compressor could muster to keep it running. The big problem with air is it is terribly inefficient. You need all your big compressor can put out to run the grinder. The electric grinder is a lot more efficient.

The noise is something you need to consider too with the air grinder. Compressor running full blast, air grinder screaming at the top of it's lungs, be sure and buy extra ear plugs.

Ron

[Paul Tarlow]

Rough grind is with 80 Grit, then 180, 400, 600 and then cerium. Pumice would help after the 600 and before the cerium.

This is all with silicon carbide grit and water drip. Diamonds would be nice but costly and you need lots of running water, which I don't have in my studio.

Thanks Ron.

Is the grit loose or is it adhered to a backing?

If loose, I'm guessing its a signficant effort to clean between changing grits.

[Ron Coleman]

Rough grind is with 80 Grit, then 180, 400, 600 and then cerium. Pumice would help after the 600 and before the cerium.

This is all with silicon carbide grit and water drip. Diamonds would be nice but costly and you need lots of running water, which I don't have in my studio.

Thanks Ron.

Is the grit loose or is it adhered to a backing?

If loose, I'm guessing its a signficant effort to clean between changing grits.

The grit is loose, I just sprinkle it on the disk and add a little water. It's a lot of work to clean the disk during a grit change and one little loose piece of old grit and it's back to square one. Been there and done that many times.

Ron

[Ron Coleman]

Here's a shot of my lap grinder doing a bowl bottom. You can see the slop and mess from the grit.

I tape the bowl to the bottom of a board and use side boards to control the bottom grind. Some people freehand this operation, but I've found if you make just one little slip the scratches will show up on the back like a sore thumb. Can't have that so I use the fixture to hold the bowl.



If you stay tuned for a few days, I'm doing a write-up on cold working you might find interesting.

Ron

[Brian and Jenny Blanthorn]

Charlie, I need a heavy sprocket (#40, #50 or #60 chain) like the one Ron used to attach his shaft to the steel plate. I bought one on eBay that would have been perfect except the idiot seller mismeasured the bore. Apparently he couldn't tell 1 1/2" from 1 7/8". Here's a picture of it.

Jim

I would advise against a tooth driven flat bed

The torque on start up is immence

A bit of belt slip on start up give a gradual start

I had a friend get made a big flat bed with a toothed system

Had 2 put a expencive slow start motor when a bit of belt slip would have been a cheeper option

Ron

Bit of water technology 4 U

Drip n Go tm

If U attach a thin pipe 2 the one U got bore is about 6mm or so may B a bit more

U get better drip control as it does not glug back up the pipe

As well as this on my wet / drip machines I got a big dustbin with ball cock on so got constant water pressure

Brian

[Ron Coleman]

The reason for the sprocket.



You can just see the sprocket at the top of the picture.



Belt boy