Cordless Biax scraper.

[Pete.]

For a laugh I thought I would have a go at retro-fitting an old Blue Biax with a cordless motor. These Biax machines are long lasting but the blue ones were made in the 1960's/70's and spares have long since been unavailable. I had rebuilt a couple from bits for @pressbrake1 in exchange for some work he is doing for me, and had a pile of bits left over.

So, a £15 Ferrex angle grinder from Aldi was torn apart to see if the motor would fit up to the Biax. Turns out it was a good match having the same diameter bearing and shaft.

I needed a 9mm thick adapter plate. The plain back is where the Biax gearbox bolts up to, locating on the 51mm hole. The 63mm step locates the grinder body.




The grinder motor had a plain shaft with a bevel gear secured by a woodruff key and criclip. I removed the gear, clocked it up in the 4-jaw and turned the shaft down to the bearing step.



The Biax has a spiral gear on it but I can't cut those and I needed to make the mating gear anyway so I cut a 6 tooth pinion of about 6mm diameter from silver steel and fitted it into the end of the rotor.





Next I had to borrow a gear shaft from another machine (coz this is one of the bits I'm missing) and made a plastic gear which is pressed onto the shaft. This mates with the pinion.



After that I put it all together and it works a treat.

3 good passes over this scrappy old plate and it's only lost 1 light on the 40V battery.

 

[scottmk1]

Top job Pete

 

[not done it yet]

As I thought, over at the other place, you would be scraping something!

 

[Maker]

Very cool.

 

[Colin H]

That's a neat solution. I have just got one of those Biax and the one worry is if the motor goes pop.

 

[pressbrake1]

That's a neat solution. I have just got one of those Biax and the one worry is if the motor goes pop.

Ham fisted students murder biax regularly

 

[Colin H]

Ham fisted students murder biax regularly

I have 4 weeks to get it out my system on my own so I don’t ruin yours

 

[Pete.]

Thank you for replying to my thread it reminded me that I forgot to add the latest update.

So the £15 grinder worked great but try as I might I could not get it to work on variable speed. I blew up several (four, I think) circuit boards trying.

Then I found this on Amazon for £35 (price at the time).

Has a brushless motor, variable speed built in and uses the very popular Makita batteries. A couple of evenings work and I had it mated to the Biax gearbox like this:

 

[Stueeee]

Nice work, I'm no kind of expert, but that cordless Biax seemed to have a nice balance when I had a quick try out of it at yours last week

 

[barracuda816]

Never having heard of a biax until today. How does it differ between say a multi tool with a scraper blade? (Kind of asking if I need to buy a nice new tool to scrape old undersell off my classic cars )

 

[Keith 66]

If you can find a Bosch power scraper (PSE180E) they are very good at scraping paint & underseal. It was sold as a power scraper & chisel, straight reciprocating action. Bosch discontinued them a few years back which is a shame.
I have used one to scrape 50 years worth of antifouling off our 27ft yacht, its now two thirds of the way through scraping thick pitch off the back of a lorry load of teak floorboards i bought recently.
I havent tried it for scraping cast iron yet but might give it a go!

 

[Colin H]

Just before the biax came up for sale I bought one of these Dewalt saws to convert. Still tempted to make a little kit and have a go.

 

[mm289]

Very impressive, as normal - battery life?

Paul.

 

[Keith 66]

Re the Bosch power scraper, This afternoon i had an experiment, silver soldered a carbide tip on the end of one of the straight chisels. It sort of works but even on lowest speed its too fast & the lack of weight means it is virtually uncontrollable. I will save it for cleaning tar & antifouling, It was worth a try!