Rebuilding my pt104 bender w/air over hyd.

[Rob G]

I was given this bender about a year ago from work. It was used mainly for fence and railing jobs. According to the guys at work, it`s probably around 15 years old, and, pretty beat up. It appears that someone liked to use a waffle faced hammer to drive in and remove the pins and also to loosen the tube and/or pipe. ( It had a 1 ½” x 6” radius pipe die in it when I found it. Then while doing some cleaning up/scrapping of old press dies a couple of weeks ago, I scrounged up a 1 ½” x 6” radius tube die for it also.)

Needless to say, but, it was pretty beaten up. The main die/pivot pin hole was wallowed out slightly along with one of the follower die pin holes. Also, the edges of the swing arm were dinged up pretty good from being hit with said hammer. The stand that it was mounted to was bent and the mounting foot was ripped about halfway off.

The rebuild: ( The pictures don’t follow the timeline but are relevant to each post.)

I knew that I wanted it to be portable and also wanted to use an air over hydraulic shop crane ram. I was going to modify my old engine stand and mount it to that, but at the last minute my dad said he needed to barrow it for a while. So, after taking some measurements and digging thru the scrap pile I came up with enough square and rectangular tube to build a cart with.

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture027Medium.jpg

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture030Medium.jpg

I started on the bender itself by blasting it to remove the paint and crud build-up, and also, to see what exactly needed to be fixed. ( I should note that the arms are only .500 thick.)

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture086Medium.jpg

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture0203.jpg

The dents on the edges were cleaned up with a file and a flap disc. The main pivot pin holes were egg shaped, so I drilled and then bored them out to 1.125”. The follower die pin hole was not as bad as I thought so I decided to leave it as is for now. Now it was time to start turning the oil-lite bushings to be pressed into the now over sized holes in the main frame arms. I started with some 1.500”0.d x 1.00”i.d oil lite bushings, turning the o.d down to 1.130 also leaving a .250 thick shoulder on the end.

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture009Medium.jpg

[Rob G]

The swing arm bushings were turned from some 1.250” o.d aluminum/bronze bar stock. The upper arm bushing was turned to the same dimensions as the others except that it has no shoulder. The lower arm bushing is the same with the addition of a .215” tall shoulder to keep the die centered in the frame. All bushings were then pressed into the arms.

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture0206.jpg
Lower swing arm

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture015Medium.jpg

The ram mount:

I made this based off of a design I saw (I believe) here on pirate. I started out with a piece of tube with an i.d slightly smaller than the o.d. of the ram body and about 4” long. Then cut it open lengthwise.

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture016Medium.jpg

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture010Medium.jpg

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture019Medium.jpg

[Rob G]

Next, cut 3 pieces of ¾”x .120 wall d.o.m tube 2” long. Spaced approx. 1” apart across the cut then tacked them in place. Then using a cutting wheel I cut them in half along the cut in the tube. Spreading the tube apart it was slipped over the ram body, the clamping bolts were installed then they were welded in place. Note: ½” bolts are a very snug fit. I had to tap them out with a hammer and punch. Ended up using 7/16 bolts instead.

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture087Medium.jpg

Next I chucked up one of the main frame spacers in the lathe and shortened it by .060” to allow the ram to pivot on the bolt. The ram was then positioned in the center of the frame and the mount was tacked to the spacer.

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture088Medium.jpg

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture090Medium.jpg

Next up, a 5/8”to ½” bushing was machined for the hole in the end of the ram. The “eye” pivot mount started out as a piece of 2 1/4” round stock 1 1/4” long. An 1 ¼” hole was drilled/bored thru it in the lathe, then, a ½” hole was cross drilled thru it.

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture103Medium.jpg

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture094Medium.jpg

Next post

[Rob G]

Next a swing arm spacer was machined the same as above, then the “eye” was slipped on the end of the ram, bolted in place, and then tacked to the swing arm spacer.

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture104Medium.jpg

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture105Medium.jpg

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture113Medium.jpg

Everything was mocked up and a dry run was done to check for any binding. Then it was taken back apart for full welding and paint.

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture006Medium-1.jpg

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture114Medium.jpg

[Rob G]

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture020Medium.jpg

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture021Medium.jpg

Finished !

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture038Medium.jpg

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture036Medium.jpg

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture043Medium.jpg

[Rob G]

1 1/2 x .120 dom

http://i159.photobucket.com/albums/t150/robg_010/th_bendervid.jpg (http://s159.photobucket.com/albums/t150/robg_010/?action=view&current=bendervid.flv)

Repinned die once to get 90*.

http://i159.photobucket.com/albums/t150/robg_010/Bender/Picture072Medium.jpg

[tech201]

are the T handles near each caster to level the bender? where did you get the spring.

[stealthcammo1]

any vids of the return using what looks like a door spring. and do you remember what id. and od. the piece of tubing (you used to pinch the ram) was? im just about to build one the exact same thing except the cart is gonna fit my welder and plasma on it also.

[Rob G]

are the T handles near each caster to level the bender? where did you get the spring.

Yes, the T-handles are for leveling. The spring came from the local hardware store.

any vids of the return using what looks like a door spring. and do you remember what id. and od. the piece of tubing (you used to pinch the ram) was? im just about to build one the exact same thing except the cart is gonna fit my welder and plasma on it also.

No other vids at the moment. I will say that the spring is not strong enough to close it by itself, but does make it easier to close by hand. I think that I`m going to swap it for a short garage door spring. The piece of tubing is 3 1/2"od x 3"id x 4" long.

[stealthcammo1]

thanks. and awesome write up btw