Speed reducer

The saw barely cuts thin sheet metal. The blade is a 14 tpi bi metal. New. I think that the SFPM may be too slow. Or that the teeth at 14 tpi is too fine.

Suggestions please.
 
Make sure the teeth are pointing in the right direction? Does it cut wood?

John
 
I think the minimum recomendation is three teeth on the stock at all times.

What is the thickness (inch dimension or gage) of your "thin sheet metal".

If your "thin" is roughly equivalent to my "thin", 14 TPI is way too course.

This information explaines it pretty well.
 
The sheet metal is thin and doesn't meet the 3 teeth guideline but it will cut it if I go slow on the feed. It won't hardly make a dent in steel. I have tried different thicknesses up to 1". All I get is a shallow groove maybe 1/64 to 1/32 deep.

I thought about the teeth going the wrong way. I am pretty sure I have the teeth pointed in the right direction. Maybe I should flip the blade.
 
The teeth are going in the right direction. Sliced right through a piece of 3/4 x 1 1/2 pine. No go on 1" steel.
 
14 tpi on 1" steel would be really slow and likely plug with chips. I'd use a 6-10 tpi bimetallic and 120ft/min, if there is pressure and speed, it has to cut, imo.
 
Been looking a saw blades. Only found one source for a bimetal 80" 6-10 tpi blade. Price isn't bad at $24 plus shipping. Also thinking about changing the driven pulley from 7" to a 3" or 4" pulley. A 3" pulley would give me a sfpm from 98 to 261. A 4' would be 73 to 198. Will try what I have first to see how it cuts.
 
I was using my 3x6 horizontal today and it slices through whatever I put in it. Checked the manual. It runs at 133 fpm with a 14 tpi blade. Confirmed that the blade has 14 tpi. Counting the teeth was not easy between holding a flashlight and a ruler. Then trying to keep track of the teeth count. So just for grins I got out a thread gauge. A 14 tpi gauge fit the blade. 12 tpi or 16 tpi didn't fit. I bet all you old timers at this new that trick.

My next step is going to be to increase the fpm by swapping the 7" driven pulley with a 3" pulley. This will get me 130 fpm
 
Needed to round the corners on a 3/8" thick exhaust flange for the header on my 66 Midget project. Decided to give the band saw another try. It was slow going and I needed to keep the right amount of pressure. It did cut slowly through the flange. Still going to get a smaller driven pulley to up the speed some more.
 
I cut a sheet of 1/4" CRS Friday and used 180 ft min. Starrett recommended 230 ft min (on the chart and from memory). I did call Starrett the other day and was put in touch with their local tech rep. He said to slow the speeds some for running dry. He suggested 175 ft. I can't say I had the highest confidence in his advice. I think dry sawing isn't something they deal with much these days.
 
You must log in or register to reply here.
Back
Top