Building an enlarger chassis

[Tracy Storer]

The point about it being properly balanced isn't something I had thought of, but you may be right, I'll do some testing. Are you sure the rack is 20 degree pressure angle? I was assuming it was 14.5 degree, which most older equipment used, but if it is 20, that would be easier for me to source, as it is the more modern standard.

I have a gauge that has 14.5 deg PA on one side and 20 deg PA on the other, and neither one looks perfect ! I believe 20pa is the older type, but could be wrong.

Another option would be to replace the pinion on the head/carriage with a gear that matches a more commonly available rack (why didn't I think of that yesterday?).

[Ethan]

I have a gauge that has 14.5 deg PA on one side and 20 deg PA on the other, and neither one looks perfect ! I believe 20pa is the older type, but could be wrong.

Another option would be to replace the pinion on the head/carriage with a gear that matches a more commonly available rack (why didn't I think of that yesterday?).

which PA fits better? Both have been used in the past, but if if I remember correctly, in the past 14.5 was more common, but now 20 is more common. Although it is easier to find 20 PA racks, the ones I have found haven't been any cheaper, so I may just buy one PA, and if it doesn't fit, buy a pinion to match.