Well I recently Got some mandrel bent piping. Ordered a bunch of stuff.

I wanted to acquire the material first for the project.

I was wondering what everyones suggestion is on the way to cut this stuff.

I wanted to section out the 180 * bend for some 30* and or possibly a 40. Depending on what it is. I looked into abrasive cutting saws with a largre 14 inch disc and noticed it wont allow be to cut 180 properly. Also I see some "cheap" models offer a protractor, and now that i look further its only a 45/90 setting. I thought it was a protracator with diffrent increments.

I also looked into a Small horiz band saw.. And noted how that wont work as I do Have a Porta-ban that can cut some of the smaller 180* bends I have.

I also looked at a vertical band saw and know how they work and whats up with them. I just dont have the money to buy a large saw that is good for cutting stainless. I bounced back to my idea -(easiest) with the abrasive cut off saw. Whats everyones take on how we cut this with angles. I know a vertical band saw makes the most sence..

Attached are a few pics of what I am talking about/working with. THanks in advance

 

band saw FTW

 

Ok, Well a Horizontal band saw will now work. I need to be able to cut angles out of the 180* bend. Within the 180* there are 2 90* fittings.

I may need to harvest a 30 or 40. Out of the 90* a band saw has a jaw that only clamps and does not angle.

A vertical band saw my be my best bet but I dont have one.

I thougt a chop saw would work best- But i have never done this type of fabrication as the bends are $$ and its basically a 1 shot deal cutting.

 

Hot saws don't cut particularly straight and there will be quite a bit of flex in the blade (even if you use a 3/32" blade - which flex's enough to take out a good 1/4" or more). The result is you end up having to sand them quite a bit and you've eaten up a lot of material. Your worst issue with hot saw is if your down force is too high you will distort the blade and cut the material at an angle.

I would suggest a 4.5" cut off wheel on a 4.5" right angle grinder and just pre-mark the tube well and follow your line. You will need to sand afterwards, but those discs are so thin (1/8" or less), that you barely will waste material with a blade that thin.

The only really good way of doing this is with a vertical tilt (traveling) band saw. U-bends are clamped down to a t-slot table, the saw doesn't exert a ton of force on the material so clamping isn't a big problem, and the saw comes forward and cuts through your material at specified feed rate. Works like a charm.

I've also experimented with cutting u-bends on our waterjets and it was a disaster. Cold saws require too much clamping force unless you have machined clamps. CNC mills give you a great 90 but just ruined the other half of the material. ETC.

 

Went and got a chop saw. Invested in a better blade @ the welding shop.

spend like 100 today on saw/blade. No biggie. Project is months bhind.

I have to work on my angles and transistions.

ended up having to stop becasue I could not figure out the offset I needed.

In not long I had things tacked up.

Also had time to square up with my bro, ANd fab his wastegate

 

You can mark your angles with just about anything that can measure in degrees. Mark your line and cut them dead down the middle with the chop saw. Make sure you are cutting the pipe SQUARE in the bend, otherwise when you go to meet up a straight to your curved section your curved will be taller than your straight.

In all honesty, when I do fab work like pipe routing I have an angle finder and a measuring tape. The rest is a lot of eyeballing, test fitting, and fine tuning with a sander/grinder. I've found that trying to use a bunch of angle finding tools and whatnot never accounts for small angle deflection of blades, or the car being a little crooked on the lift, etc etc etc and I end up having to make small adjustments and a bunch of test fitting anyway. I use them to get me close, then I work from there.

 

Yea it is tricky. I am looking @ a picture, and just buying material.

I made it pretty far, but had to stop to pick up on the other project.

Did you see the pics. The first one I cut a 1.5 inch spacer and than transition it into the 35* bend... I think it looks pretty strait as far as cut-

I have to create something that takes almost a cork-screw turn becasue i guess i did not think it over to well.

 

First cut looks good, fitment is pretty much perfect. Don't really get any better than that. Was kind of just going over the basics of how I do it in my post.

If you have a corkscrew, what I usually do is take 2-3 ~35* bends, one of which has a straight attached to it. Then I just kind of work them around in all different directions until I get the straight on the end to point where I want. Mark, tack, check. Rinse repeat lol.

PS, Bucks as in bucks county PA?

 

Yea . PA BUCKS

I made it preetty far but had to stop.

 

Nice work man!

 

Hey- Chimmike- Thanks!

 

So some of you other guys wanted to chop me up in the other threads I had posted. I went to school for welding.. I can do it all. I just mainly focused on welding stainless. When I was younger I welded every process possible. After doing it all, I realised I like stainless. I knew How it was clean. Thats all I liked. I didnt like handling steel.

I landed a pretty decent job right out of high school. majority of stainless. Exposed to some navy/goverment work.
Anyway I left welding job years ago. worked at other heavy equippment places repairing large earth movers, buckets, arms for backhoes. basically welding and line boring. Ended up giving up welding as a job. Started doing it more for my self and doing projects. Anyway I recently purchase a miller Maxstar 140STR about 2 years ago. I used it to stick weld a few times and spent alot of $$ on the TIG setup to match my WP20 setup on my syncrowave.

Havent touched a TIG torch in a few years. Welded my downpipe up No problem. Used .30 filler to weld the V band and I knew I still had stainless in me. All i ever focused on was stainless and almost went to a space oriented program to start welding Titanium

This was welded with my 140- hooked into 230V its got that special ****. Amazing technology. 3/32 tungsten, .30 filler. filler is hard to even use/handle. I weld with out a glove

 

a vertical bandsaw is what you'd really want.

I have a Dewalt portaband that is attached to a special mounting table and foot pedal to make it a mini vertical bandsaw. the bracket it mounts to is made by some offroad company and is pretty sweet. you can probably google and find who makes it.

 

I have a portaban band saw- But I already cut my pipes and done the project

I was considering a band saw- I purchase a abrasiv chop saw, ended up having to use a end mill and mill a 50* angle which I could not get on the saws I had.

 

just for future reference. if yours will fit onto that bracket that I was referring to, I would highly recommend it.

 

I use a vertical bandsaw then hit it on a belt sander to get it perfectly flat