Kennedy Hexacut machine hacksaw

If it works for Hotpoint it will work for me.

The polyvee belts used on tumble dryers are not the same construction as "standard" belts - they use a slightly elastic tension member to make the belts "stretchy"

The reason I know this is that a company I worked for modified the "belt building" machines used to make the belts (by a company in Wigan) to have a closed loop tensioning arrangement to wind on the tensioning cord, which had to be applied at a specific tension to get the correct stretch required. Normal belts used a non-stretch cord.

The stretchability may have been to enable the removal of a separate tensioning mechanism ( engineering by accountants ! ) & the installed tension was high. Tumble dryer installations used grooves cut directly into the motor shaft (around 12mm or so diameter IIRC) & a large diameter plain face "pulley" on the rear of the drum, giving a very large gear reduction.

Polyvee belts in general require a lot of tension to work correctly & wear fast if under tensioned - the amount of wear required on the flanks of the vees isn't much before the belt just ends up driving (more likely slipping) on the points when they hit the bottom of the grooves.

Can't say I am a fan of polyvees though, to be fair, the installations I designed them into were normally "challenging" and where a traditional vee belt solution would not fit the space available.

Nigel B.

Thank you for all your help. Pro tem I have bought a Scheppach bandsaw from Screwfix and, after fettling, it it does what I want, viz making brass discs for my friend the golf pro to use in the ball machine. I didn't realise how much I relied on the Kennedy.

I had a big metal bandsaw years ago but could never get it to do what I wanted and sold it. The Scheppach now cuts square - and quickly! - and the job is now done.

I will revisit the Kennedy at a later date, probably with v-belts. Having reached a dead halt had prevented me from getting on with other projects of a more important nature - including viola bows.

What a great site this is!

Leo

I could never get the two pulleys parallel on my saw so the belt just kept coming off.   Its been dumped under a bench for years now.   

Edited By Buffer on 18/08/2023 15:29:47

Hi Buffer,

The common fault with this machine, and it is down to wear in the crank bearings. The crank pulley automatically swivels clockwise due to this wear and in doing so sheds the belt. This wear is due to the high tension required by the original flat belt. With my muscle illness I struggled to get this belt on and off. When the saw is set-up correctly according to the manufacturers data.

Also I have seen that some saws have motor pulleys with 16 mm bores running on 5/8" shafts. How this ever worked from new I will never know.

The Poly V has very minimal tension when compared to the original set-up. I had the machine set-up and running in under 5 minutes. With the belt running dead centre on the larger pulley rim.

Regards

Gray,

A few days ago I promised that I would post a few photographs of the conversion.

The next photograph shows the new ribbed pulley. Which is all that is required to be made to convert this machine.

Lastly the saw in action, if you notice from the the blurr on the hacksaw frame this is taken with the saw in motion.

The material is 40 mm Aluminium and the saw cut through this in several minutes.

You might also notice the Brass swarf from the previous cuts this morning.

Regards

Gray,

I think I’ll do this. What length belt and where did you get it? I can turn up a new pulley in aluminium.
You should be ashamed of the brass swarf - but don’t worry too much. I’ll post pics of the area under MY saw!

Hi Leo,

My apologies for not getting back to you sooner. I seem to have had computer problems this end.

The belt Ref No. is 559P/220J _10 RIBS. I purchased my belt form Simply Bearings, (Usual disclaimer), it was here with in two days.

I am going to send you an PM with my email address so that you can have the PDF drawing of the pulley.

Regards

Gray,

I have a Kennedy model "90" hacksaw, which is much larger than the "60" (Hex bars are 21mm AF)

I've never managed to get the flat belt to run on the centre of the large pulley.

So seeing Graham's Poly belt conversion I decided to do the same to mine.

Been a larger machine the dimensions are different to Graham's.

Large pulley diam. 9.875" (251mm)

Small pulley diam. .96" (24.38mm)

Centre distance of pulleys 6.8125" ( 173mm)

Graham very kindly calculated the Poly belt length as 34" ( 864mm)

This was purchased from "Simply Bearings" Part No. 864PJ/340J-14Rib

As can be seen in the photo the belt now runs nicely on the centre of the large pulley and is far easier to put on than the old flat belt.

Graham you have a PM.