Shrinker Stretcher

**Charst** · Jan 20, 2018, 12:04 AM

Hi Folks

Just wanted to show the result of the last days of work on FREECAD on my Shrinker/Stretcher.
Waterjet cutting is already in progress and abt. 90% of the other parts are in my workshop and waiting to be assembled.
Apart from the 300 mm throat depth, one special feature are the swiss made jaws from ECKOLD with quick release mechanism. The machine is designed for 1.5mm mild steel sheet metal or 2mm aluminum.
Machine uses a pneumatic membrane cylinder from a truck brake system. It will bring 3 tons of pressure on the jaws by putting 5 bar of air pressure on the cylinder.
Will post photos when it is finished (hope this is done sometimes in March 2018).

Greetings from Germany

Charst

Shrinker Stretcher-shrinker-stretcher.jpg

**bimmer1980** · Jan 20, 2018, 06:29 PM

Looks like a nice design!

I'd be interested in a set of the .stp files. I just got solidworks, so should be straight forward to open the files.

I'll be interested in seeing some pictures as you get all your parts together and start assembling it!

Thanks for posting!!

**mwmkravchenko** · May 24, 2018, 06:02 PM

I'd be interested in the step files. If they are available.

mark at kravchenko-audio.com

**Mi Tasol** · May 25, 2018, 12:07 AM

Hi Charst

Any project photos and finished parts to show to those of us who are interested and jealous yet?

Mi

**KustomsbyKent** · Sep 27, 2018, 07:19 PM

Any progress updates?

**Charst** · Oct 4, 2019, 11:34 PM

Hi Folks! It's been a while...

Here are some pictures of my finished Shrinker/Stretcher. Works great. I optimized the working speed (cycles per minute) by implementing a quick pressure release valve on the pneumatic membrane cylinder. Depending on the work piece it can be up to 30/min now. I also figured that the forces required for shrinking are way higher than for stretching. With the current setting it easily shrinks 1,0mm mild steel and stretches up to 1,5mm. If I had to do one again, I'd use a larger membrane cylinder and a stronger material for the excenter (see 3D pic) which is 2x 12mm plates made of S235, bolted together.
Just ask if you have any questions...

Charst

**juan_alberto_13** · Oct 10, 2019, 06:19 AM

Hello charst, incredible team that you designed, please let me know to do it for my workshop and I want to know if it is possible to obtain the information of plans and measurements and where you got the Eckolds, sorry my English is quite bad and I use a translator since I only speak Spanish

Thank you

Juan Alberto

**ianinsa** · Oct 10, 2019, 08:25 AM

i too would be interested in drawings etc. if you would be so kind.
ian214@live.com-thanks in advance

**arthurinatasha** · Dec 21, 2022, 11:54 AM

Thanks Charst for that great device! I am interested in step files. Is it any chance to get ones?

**mwmkravchenko** · Oct 5, 2019, 07:42 AM

Awesome pictures! I see a quality tool that you have made. Something like this can be very useful for panel work and even bending bar and angle iron. If you were to do it over what metal thickness do you think it would be capable of shrinking or stretching?

Did you ever release the STEP files? I use FreeCAD to!