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Best way to cut off Therefore sewer fitting and replace with standard 3" fitting

December 22, 2016, 08:58:23 am

I have had nothing but leaks using the original sewer connector fitting with a flimsy adaptor  on our 97 U320.  So I ordered a new glue on fitting (ABS I think) but cutting off the old white Thetforb fitting looks difficult due to not much clearace around the pipe.  Anyone who has done this might have some advice.  Thinking of trying the Dremel tool with a metal circular saw blade.  No room for a sawzall.  Will a hacksaw blade taped up do it? Advice?

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Re: Best way to cut off Therefore sewer fitting and replace with standard 3" fitting

Reply #1 – December 22, 2016, 09:18:30 am

Hacksaw blade taped up will work fine or this handle Problems viewing Target.com?
Once you get through the wall thickness it goes pretty quick. Just take your time and keep the blade straight as possible. I used the clear cement from home depot it says on the can can be used for ABS.
If you can do a dry fit and make sure all your adaptors and hose whatevers have enough room then glue er'up!

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Reply #2 – December 22, 2016, 10:17:12 am

If the above solution will not work, then you might try a "wire saw".  These can usually be found in big sporting goods or camping stores.  They are called "wire saws" or "survival saws" and are inexpensive.  I have had one in my tool box for decades, and every once in a while it comes in handy when NO other cutting device will work.

Rothco Camping/Survival Commando Wire Saw - Walmart.com

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Reply #3 – December 22, 2016, 10:24:41 am

A Gerber folding saw might work--has two different type blades.
ACE has a very nice compact hacksaw that uses blades about 1/8" high x 6" long in a very compact holder.

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Reply #4 – December 22, 2016, 11:06:04 am

+1 on the wire saw, although I could not find mine when I made the same change you are preparing for and a sawsall worked fine for me.  You just have to make sure the tip of the blade doesn't hit the wall.  I had enough room for it.  I replaced the Thetford fitting with a Valterra valve, not just the Valterra fitting.  That's an upgrade worth considering.

Any hardware store plumbing dept should have the wire saw.  Plumbers use them to cut pvc that is in hard to reach areas.  It's just a piece of steel cable that has no teeth but uses friction to melt the pipe.  Works much better than it sounds, once you get it started.

Eastman Galvanized Steel PVC Cable Saw-45092 - The Home Depot

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Reply #5 – December 22, 2016, 11:15:47 am

They actually make a wire saw for this purpose, look at HD or Lowes in the plumbing dept.  You need to keep the pulling ends square to the pipe for best results but a not quite square or perfect cut won't make any difference.  Plently of coverage with the new fitting.

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Reply #6 – December 22, 2016, 11:26:38 am

I just removed mine from the gate valves and took it over to the miter saw. Easy peasy!
 
Trent

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Reply #7 – December 22, 2016, 11:53:32 am

I used a piece of string! It was the kind a bricklayer uses to keep things straight. Wrap it around and pull back an forth. It goes quickly an straight. I saw it on you tube. It works.
Raymond

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Reply #8 – December 22, 2016, 12:27:50 pm

If you need to save the length of pipe (so you will have enough room to glue on your new fitting) rather than cutting the pipe off we cut 3 slits across the white Therefore end piece with a rotary tool. We take a Mack Daddy hair dryer (real heat gun) and heat one white plastic section at a time. Once one section is hot you can take a flat screw driver and a pair of pliers and peel the section off.  Now all you need to do is clean up the area with emery cloth and glue on the new end with the proper glue.

Pamela & Mike

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Reply #9 – December 23, 2016, 09:13:43 am

I second Pamela and Mike.  I slit my Thetford fitting in several places and it broke off without heating and without damage to the pipe.

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Reply #10 – December 23, 2016, 09:19:28 am

If you have access you could try a die grinder or the equivalent from the inside of the pipe.

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Reply #11 – December 23, 2016, 12:05:26 pm

As said earlier, a piece of string.

Read about the salvage operation of the MV Tricolor, same concept. You don't need abrasives for plastic cutting.

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Reply #12 – December 23, 2016, 05:14:42 pm

Makita reciprocating saw, no muss no fuss its gone.

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