The Crispin Colloquy

I only have a Gritzner manual, but it looks pretty much the same as my machine. I got the manual from someone on Leatherworker.net, and I can ask if it is okay to share it here.

The Frobana models I see on the internet are mostly different from mine, reflecting the changes the company made over time. Mine does not have a cutter on the feed dog as some do. The manual I have advises to groove before sewing. Re. the thread, likely the later machines could take heavier thread, I dont have a manual for my specific model, nor is one obtainable at this time. Thats why I'm so grateful to get the opinions and experience of others who have restored their various machines to working order. I hope what I write here will help someone else who finds themselves with an old machine and no specific manual.

The junker ruh pdf manual (actually a Pedersen manual) on DW Frommer's Bootmaker website is also helpful. That machine uses Gum Tragacanth in the upper thread reservoir and waxed thread in the bobbin.

Regarding wax/heater: This machine has only an oil (gum trag) reservoir, and the stem and eye to hold the thread inside is corroded, so I'm reluctant to try the Sellaris at this time. I'll try to get a photo of the damage. I'll see if I can get my car mechanic to figure out which way to push the lever without breaking it to release the gnurled wheel. He unstuck one of the screws on the reservoir already! The lever & mechanism has one heck of a spring on the bottom.

The knurled thing looks (guessing) like it cuts a vertical channel in the outer sole for stitching in before it's stuck/mounted to the welt. That knurled wheel would make a mess of a welt, it probably bears on the flesh of the sole. Seems odd still, because the channel cutting feed-dog does a fine job, and is adjustable for depth of cut and everything. History's Mysteries.

The knurled wheel would make a mess of the shoe too, its wide. I'll experiment once the mechanic gets it unlatched. At serial number ~6000 this Frobana was one of the early models and there were likely many changes made over the ensuing years. The channeling feed dog either wasn't purchased or wasn't invented when Frobi was made.

Now, just a few miles up mass ave. Cambridge Robotics / Boston Dynamics is making robot dogs. I'm just trying to get Frobi up and running! And get Frobi so it doesn't chew up the Sunday paper....

I will add the rest of the manual as I have time, I'm on a shared computer and have to compress the photos also. This is small, and runs ~16 pages long. The pdf was kindly given to me by a person on Leatherworker dot net and he gave me permission to share it. It is in the public domain as far as I know, Frobana and Gritzner have long since been shuttered.

The original German instructions are here:
https://www.cabrio-heckscheibe.de/app/d ... 1560713937
a better scan for a newer version of the original German version is in the PM that I had send you.

@SharonKudrle , pg. 9, Fig. 38 shows the channel-cutting feed dog I was describing.

Yes. None on my frobana. Im used to cutting my own channel, not spoiled owner. Retro ;)

I get to choose sidewaysflap, depth, vgouge, cutandclose, etc.even fed rightside up.

If yours has the feed dog in Fig. 38, beware, it'll cut a vertical channel as it feed and take your flap right off.

@das the original manual says that the upper thread runs through a "Tragant" container for thread impregnation. Since Tragant does not appear to be available any longer, somewhere I read that instead of Tragant also a soap solution could be used. I used mostly pure water until now. Would you have any recommendation on what to use?

Thanks!

Thank you for the warning Al, but there were three feed dog options, and mine is the one that has no knife at all.

Gum tragacanth can be bought easily.

Hah "Tragant" -> "Tragacanth", amazing what difference a couple letters do to search results delivered by google...... Thanks.

@SharonKudrle Then sounds like you're good to go, take Frobi for a spin.

@carsten Gum tragacanth (plant gum) is a water-based solution used here mostly for burnishing the edges of shoes and leather items. It will be fugitive on the thread and wash away quickly. The Solari's liquid stitching wax I mentioned is very common in the U.S.A. for sole stitching machines, it lubricates the thread while it's moving, then hardens-up when dry to a permanent coating impregnating the thread with a rosin-like substance, similar to shoemaker's wax, though a light blonde color it leaves white thread white. I would fear a soapy water solution, besides being fugitive, would also leave the thread slippery, rather than locking it into place? Anyway, I only used Solari's in my Frobana, and it worked flawlessly--never tried gum tragacanth.

@das thanks! Makes sense to me. Not sure if we have something equivalent over here. These liquid car wax for polishing comes to mind but that probably is not adhesive when dried out. Maybe i have to come up with some kind of liquid handwax....

@carsten Nothing like the liquid car waxes. Mostly used by shoe repairmen in curved needle sole stitchers. Maybe Solari's liquid (stitching) wax is sold there too?

Wow, came home to find the cover off the car, maybe time for carwax!

@das Thanks. The usual suppliers like e.g. Goetz dont´seem carry anything similar. Google shows some hits for "SELLARI'S STITCHING WAX" sold in the US. I assume that is the one you mean. I have to look deeper into it.

Sorry, I will have to re-take the photo of page "ate" , the computer "hijacked" the photo. Anyway, the substantial part of the Gritzner Frobana manual is uploaded. I hope this is as helpful to others as Leatherworker and the HCC have been to me. Again, this manual is courtesy of a Leatherworker dot net contributor.

BINGO! Looks like you're off and running, or channeling.

I have a question about my skiver. This one I bought used a couple of years ago, but it did not come with a manual. It was apparently manufactured in east Germany and works well in general. However, I do have some problems about the feeding barrel (1). Either it does not move, or it moves just much too fast when I press the foot pedal. Since I did not know better, I used regular motor lubricating oil for the clutch mechanism and filled it into the hole (4). The adjustment screws (2) and (3) regulate the speed and initiation of the barrel rotation. (2) appears to regulate the "pedal-kick in" and (3) the maximum speed, but it seems to be impossible to adjust it to a soft start and moderate transport speed. Does anybody have a hint what I can do about it?

Any help would be greatly appreciated. Thanks, Carsten

@carsten I defer to others on the skiver adjustments, but would urge you to try and find a manual first--the steel feed barrel can destroy your bell-knife skiving blade in a millisecond if adjusted too high so they touch, even just lightly--ask me how I know, LOL. If your feed barrel is controlled by a belt (leather?) I'd check the condition of that first, it might be slipping. The skivers with a feed stone, on the other hand, can "kiss" the blade like a feather briefly after sharpening it, to de-burr the inside of the bell-knife, but otherwise must also be kept clear from touching it in operation.

For lubricating machines of this weight, I strictly use "way oil" https://www.mscdirect.com/browse/tnpla/ ... gLb-fD_BwE It is non-detergent and won't foam-up out of the oil port or out of the bearings at high speed. Being thick and clingy, it adheres to the parts without drooling out as fast as non-detergent automotive motor oil. IMO light sewing machine oil is way too thin for these, it will drain out of the bearings leaving them dry, and only leave you with oil stains on your shop floor.

carsten,

I have a Fortuna (used to have a Pedersen as well) Never see one like yours. IIRC, neither the Pedersen nor the Fortuna have the "adjustment screws" you mention, but I've never seen a skiver that didn't engage abruptly as well as feed material quite briskly. I'd almost say that a slow start would be counter-intuitive if not counter- productive.

And I agree with @das, unless you're planning on skiving rubber outsoles and the like...which, AFAIK, is what the steel feed barrel was designed for...I'd ditch it in favour of stone.

Thanks @das and @dw. Well it has already a stone feeder (in barrel shape, which is proably hard to see on the photo) so I guess that is Ok. Maybe I have to clean the clutch - I am not even exactly sure how it works. It must be some hydraulic principle.

It's not so much the start-up that bothers me but more the rapid feeding. I would like to be able control the stopping point better - meaning in a range of 2-5mm, in cases when I don't want to skive the entire edge but only part of it or until an inner corner before I turn the material. Sometimes I find my skiver just a bit too hungry. As always its very difficult to find the manual - So far I have seen this machine only twice on the used machine market. One of them is the one on the photo.

@carsten All I know is my elderly Consew (Fortuna "SAS" clone) has a (coarse carborundum) feed-stone that can "kiss" the blade to de-burr it after sharpening, the manual says. A friend's much larger (1940s) Fortuna has a toothed steel feed-barrel that is capable of destroying the cutting edge of the bell-knife "instantly" if adjusted too close. On mine the clutch motor is the only "clutch" in the system, and they can be grabby on sewing machines, so I guess also on a skiver. Mine starts slowly, much too slow to skive with, but press a little harder and it takes off at full speed, which is not too "hungry" fast. Maybe swap-in a smaller pulley on your clutch motor to reduces RPMs? Or ease-off your motor clutch plate-pressure to reduce the "grab". Like so many machine problems, it's hard to diagnose via email without the machine physically in front of me. Sorry.

@das Good idea to de-burr it like you suggest. I have always used a ceramic sharpening rod for it. Thanks for your reference about the speeds. Sounds like you have two motors? Mine has only one 380 Volts three phase motor that drives both, the bell-knife and the feeder. The clutch is an oil filled box, one driving axle going in, one coupled axle going out driving the stone feeder + one lever that is attached to the foot pedal - can't tell at this point what is inside. I think it will take it appart one of these days to have a look at the mechanism - or maybe I will first rinse the box with a cleaner to degrease it inside and make an oil change. I can't even tell the age of the machine. It was produced by a government owned company in former east Germany, both of which are history.