Hegner springs

[Jaco]

I have 2 Hegners, both very old, purchased maybe 5th hand ?
Refurbished both machines a couple of years a go.

The small one is an M1 used for light weight cutting.
Then the spring started jumping off.

The large machine is a Polycut. All heavy duty cutting.
I had to replace the motor last year.

Getting back to the problem on hand - spring jumping off.
I ordered new springs for both machines and had them shipped pot from Hegner UK.

M1 - installed new spring. Fitted blade and started cutting. Blade jumped off and disappeared into one of the off cut bins.

Polycut - spring was still ok, but I installed the new spring, and started cutting some pine. Spring jumps off.

Anybody experienced something like this before? What could be possible cause?
No good asking Hegner as it was a mission just placing an order.

Thanks in anticipation
Cheers

 

[eribaMotters]

Firstly I bought some new bellows for my 35+ year old Hegner form this company:- Ostia Tools | eBay Stores
The spring at the back is around the tension bar. This has a v block top and bottom that sit into a couple of v cradles
I found on the school machines we had that the edges of these cradles broke and thespring tension bar could jump out. I cannot recall if it was top or bottom.

Colin

 

[Jaco]

The cradles and tension bars are all in very good condition.
I have tightened up the arms, fitted old spring, but it still jumps off.