Green Biax 7ELM Minimum strokes/min

I am trying to repair or replace the variable speed control board on my 7ELM and I have found specs for the maximum strokes/minute, but what I need to know now is what the practical minimum number of strokes/minute might be. If the speed control allows the motor to slow too much, it could overheat or even stall out. Additionally, there is probably some speed that is too slow for practical work. A bit of help here would be appreciated as Biax/Dapra just tell me to buy a new or used scraper.

Wire it direct and use a router speed control on the cord.

When the motor is running full blast on the green machines it is running 1600 strokes per minute. I never run it that fast. I usually run it 800 strokes or on 4 on the variable speed dial when I am roughing. Stroke of the scrapers are from zero to 3/4" . I like to set the stroke at 1/2" down to 3/8" for roughing, 1/4" for semi finish and 1/8 down to 1/16" for 40 PPI or points per 1 inch. You gradually shorten the stroke and speed the more points. If you email me I can send you some info on my DVD / USB stick that Dapra & Biax sell. I sell them at a lower price then eBay too for the members here. I'll scan a sheet from my scraping booklet that shows stroke and rpm later tonight and post them here. As Gbent said if you have an old blue scraper, buy a reo-stat speed control and use that as aa way to slow the scraper stroke.

nt1953 said:

I am trying to repair or replace the variable speed control board on my 7ELM and I have found specs for the maximum strokes/minute, but what I need to know now is what the practical minimum number of strokes/minute might be. If the speed control allows the motor to slow too much, it could overheat or even stall out. Additionally, there is probably some speed that is too slow for practical work. A bit of help here would be appreciated as Biax/Dapra just tell me to buy a new or used scraper.

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There's very little load on a biax and heavily geared down. I can run mine down to very slow speeds with no issues.

Ed Dyjak told me he fixes those VS controls by opening it up and using a Scotch Brite pad to clean the contacts under the dial. I haven't tried that yet though. I do know that when it is set on 6 or fastest it is 1600 stroke per min. I always say 800 is on 3. I have never counted that, but the old BIAX catalog says 1600. If you still have a copy of the booklet I gave you when you took the 2 classes in the booklet I show a photo of the motor and the T handle and in that's where it's written by Biax. You can email Ed Dyjak and ask him as he knows more about those Matabo Biax motors then anyone. [email protected]