Heidelberg GT 13x18 grippers are too low

Hello friends,
Few days ago I buy this press,after cleaning and oiling I try to run the press by hands (press didnt work for last 15 years).Previous owner only did numbering on the press.When I remove paper packing I notice that grippers are rubbing on the base plate.I thought the grippers are bent so I order new ones.Yesterday when I try to replace old one with new I notice that old one are thinner because someone use rasp and made them 5mm thick (only part where they attached to gripper carrier).Old grippers have gap 0.3mm from main plate so I’m unable to use any kind of cutting plate.I try die cutting without any plate (with old grippers) and registrations is good so I think the head is OK. There is difference in cutting between first and second gripper but 1,3,5,7….sheet are same and 2,4,6,8… are same.
My question is what should I do? Disassemble the head and raise up with another distance washer T1432 (in my case 1.5mm thick and dont know is it original or not) or try to bent gripper carrier to get more space between grippers and plate
Or anything alse?Any sugestions
I forget to write I try die cutting and I put 1mm sheet behind chase, pressure are even and pressure on machine was at 7 (can go to 22)

Thank you in advance and sorry for my english

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I had one of these presses, and normally I’d ask if you already had a diecutting plate attached, but it looks like just the bare platen. My next step would be to look at another GT to see what that setup is, to compare. Since your pressure was even top to bottom, raising the grippers may not be a bad idea.

thank you for replay
Today I have some spare time and after few hours I notice that gripper carrier are bent. cant see with naked eye but after some measuring we notice 1mm difference.After we straighten carrier everything is ok, have 2mm between grippers and bare plate

Im gonna make die cutting plate because I dont have one.When I tested I put 1mm sheets behind chase and pressure was even. Should I make 1mm plate or 0.8? What is the thickness of die cutting plate for GT? On my windmill 10x15 is 0.8mm

Start with your packing thickness for printing. Try that minus a few thousands for your plate. You can always add packing, but harder to subtract. Rather than make your own, I would buy a premade plate-Barplate has a .030 cutting plate for the GT.

ok thank you

Bozidarts,, Just returned from Our Museum print shop, where they run several letterpress Machines including Heidelberg Platen only the 10 x 15 unfortunately, but my observations may help,?

The 13 x 18, is generally regarded as just bigger but in essence same operations.

On the 10 x 15 the grippers were clearing the face of the Platen with no packing by more than 6 m/m, both exactly the same at every revolution and sweep.!

The packing that was removed for inspection, was in the order of 2/3, sheets of news print, one sheet of blotting paper and the top sheet of genuine Oiled Manilla (tympan) and there was still 4 m/m. gap.

Appreciate that, this is the 10 x 15 and not the 13 x 18, but looking closely at Your original post and THE links & Your assessment i.e. the difference between first and second gripper results, there is a good possibility that the whole assembly has been damaged previously. (not unusual in the time scale) generally the 10 x 15 and the 13 x 18 have malleable heads that carry the gripper arms, meaning that they deform on a *Pile Up* by design and are usually straightened/realigned by H/berg Engineers with a special purpose tool, in the form of a >Bending< bar around 1 Metre long, with a Boss/Adaptor head that fits over the stub(s) for the grippers.

Given the request could probably access, one of 3,
13 x 18,s locally, mid week, coming. - Good Luck.

for now everything is ok but ty for your replay Mick