Thread: Firewood splitter design

Dean

That's a very handy bit of gear. A neighbour of mine used to sell commercial quantities of firewood. He had a vertical splitter with a lifting device similar to your's. The blade was pivoted and the ram pushed upwards acting on the shorter side thus giving some mechanical advantage.

My memory is that it used a 9HP B & S motor and cost (in 2000) about A$5000, which I thought was excessive. I felt they were working to pay for the block splitter as at that time they were charging about A$75 for a box trailer load. The guy had his wife on the block splitter.

I did a quick search, but couldn't see the model they had. I did find these two below, which I think are american, but they look pretty expensive to me.

I think your design will work just fine and I can see it would work well as a bead breaker too. It certainly beats my sliding beadbreaker for split rims! No, I couldn't spot the structural flaw.

Regards
Paul

Superaxe is the one you copied from Oldneweng and most likely what you were thinking of Bushmiller.

I have one. A very well made machined

Here we go, found the old thread under my old username showing my machine.

https://www.woodworkforums.com/f13/pi...d-borer-50160/

Originally Posted by Acco

Superaxe is the one you copied from Oldneweng and most likely what you were thinking of Bushmiller.

I have one. A very well made machined

That's it. That's the one!!

I think theirs would have been the 300.

Regards
Paul

Originally Posted by Bushmiller

That's it. That's the one!!

I think theirs would have been the 300.

Regards
Paul

Can you remember if it was green or gray like mine in my above linked thread?

If it was gray, it was probably the now discontinued Ws250, which is what I have.

DJ.

I had to laugh when I read your reply calling it a SuperAxe. I instantly remembered that I took photos to assist in my building. Looked them up. It looks just like the one in your picture. They have now changed the colour scheme.

Looking at the WS300 it shows a motor of 9hp. My neighbours had a 6hp motor. I remember that it was just a bit smaller than my 6.5hp.

The SuperAxe is the only unit I have seen which has lifting ability and a proper working height table which does not require constant bending. I have the same knee operated lever which has to be moved to the right before it can be pushed in. One of the improvements I intend to make is to add adjustable depth to the table for bigger pieces of timber.

Attachment 212554

This pic of the underneath construction (taken in October 2004) shows how strong it is. The 2 outer sections are 100mm X 100mm X 6mm RHS, the middle bits are 150mm X 75mm X 8mm channel. All 6 bits are cut to sit flush with the top surface of the I Beam which I think is 250mm, and solidly welded all around. There is a gap of about 2 inches. This all adds up to 450mm width for the table.

Sometimes I have to split pieces of wood wider than 900mm and I then have to help hold them up. I am thinking about fitting a length of 50mm X 50mm X 3mm RHS in the position shown by the red rectangle, tucked into the corner, except that it will be on the other side of the I Beam. Underneath so to speak. This is because the knee lever is on this side.

A later improvement I made on the chassis after tipping the splitter over was to add an outrigger leg on the lifting side. It can just be seen in the pic in previous post thru the triangle formed by the angled support for the table. This is just a length of 40mm RHS which slides into the forward cross bar shown in next pic. It fits in the left side. It has a pivoting piece the same size which is moved by a length ot 25mm threaded rod with a winder on top until pivoting length touches the ground. I can swing off the end of the lifting frame without any suggestion of tipping now.

I plan on having a bit of 40mm RHS slide into the 50mm RHS as indicated on above pic which will extend out as needed. The 50mm RHS on the left end of the table could also be used, with a bar joining two lengths of 40mm RHS. The centre one will need to be raised to match table height.

Attachment 212549

On the subject of structural fault, maybe that is not the perfect description as it was added later to attempt to prevent an issue which although has never caused any damage I felt it would be better to fix it if possible. The problem was the twisting of the main I Beam mast when the knife was pushed sideways by crooked timber. I added some large structural supports which don't actually work at all. Does that get you closer?

Dean

Originally Posted by Acco

Can you remember if it was green or gray like mine in my above linked thread?

If it was gray, it was probably the now discontinued Ws250, which is what I have.

I have something of a mental block on the colour except that I don't remember grey. So by default It must be a green 'un.

Regards
Paul

[QUOTE=
.


On the subject of structural fault, maybe that is not the perfect description as it was added later to attempt to prevent an issue which although has never caused any damage I felt it would be better to fix it if possible. The problem was the twisting of the main I Beam mast when the knife was pushed sideways by crooked timber. I added some large structural supports which don't actually work at all. Does that get you closer?

Dean[/QUOTE]

I am getting there I think.

When I looked at the design I thought the long length of flatbar (75mm x 8mm perhaps in our money) was a little strange. If I was strengthening the UB, I would either use a small section RHS (say 25 x 25) to form a truss between the flanges parallel with the web or a series of flat bar gussets at right angles to form a series of boxed sections. This would depend on which direction I was attempting to strengthen the mast.

However both of those techniques would be difficult because the sliding knife mechanism would foul either style of reinforcing.

Consequently, you resorted to the long length of flatbar, which probably struggles to give much extra stiffness to the mast.

Regards
Paul

You are pretty close to the mark. It is actually 100mm X 6mm but that is unimportant. It is intended to prevent the mast twisting and should be strong enough for that purpose except as you point out the sliding knife mechanism limits the connection point. The top of the I Beam was capped as part of this mod with plate.

The fault is simple. I welded the strips of 100mm X 6mm on the wrong way. Its the front top of the mast that twists. The strips should be welded from the front at top to the back at the bottom.

When I fix it I am going to to use flat bar to box the section where the mechanism operates which will be welded to the offending brace after it is turned over and in the correct position. I am also going to weld some heavy (8mm) angle inside the mast so there will be more strength for the knife mechanism. One side of this angle will form the inside surface for the slide, the other will be welded to the web. The ends will be attached to the box section bars. I will need to use packing under it to clear the radius of the beam

Dean

Have you seen this one?

[ame=http://www.youtube.com/watch?v=D8gJHbT9YjQ&feature=plcp]Monday Monday - YouTube[/ame]

Dean

I understand what you are saying, but I am not sure that it would have made a significant difference. I feel that your 100 x 6 only gives additional strength over the length of the beam. I wouldn't trouble to reverse the flat bar unless it has to come off anyway. The mods you are talking about will cope with the twisting particularly if you can use heavy angle.

If you could have sourced some UC (universal column) instead of the UB (universal beam) it might have solved the problem straight up as on UC the flanges are wider and thicker. I expect you used what you had to hand but if you source from scrap yards you might be able to find something as ordinarily short lengths are not much use for anything (except hydraulic block splitters).

I thought perhaps UC for the Mk 2 version.....

It is still a good looking machine and shames the effort I made a long time ago. I too had a design flaw. It was a horizontal style splitter of the sort you are trying to get away from, but I made the sliding knife with too fine a tolerance and it rusted up. It was a fundamental flaw.It was driven off the remotes on the tractor PTO. After about 15 years, I finally gave it away to a friend about three weeks ago as he was prepared the cut off the slide and remake it. Unlike yours the slide was not removable. I am going to stop there as the failings of that project are starting to haunt me.

Regards
Paul

Regards
Paul

I am not an expert on steel designations so I had to do a bit of research. According to a UK website the web on a section of structural column has a web thickness of over 8mm so you should have told me this before I built the splitter. I actually checked all my measurements today and also checked the web thickness of the mast and was surprised to find it was only 5mm thick as opposed to the flange which was 7mm. I also told a little lie. There is no structural damage yet but the web shows signs of paint cracking which would indicate fatigue. The web needs extra strength.

Your comment re scrap yards is right on the mark as I found this piece of beam as is in a local (Mt Gambier) steel merchants stock of scrap. It is the same length as bought. The problem with twisting occurs between the top ram mounting point and the knife location so this brace will tie all the other mods together and hopefully make the mast rigid. It does have to come off to allow easier access beneath but sometimes I wish I was not so enthusiastic with the welding. I will think long and hard about this issue however as this brace does introduce some complications when changed around.

I have managed to work with this problem for many years by backing off the pressure and then going again but I worry if someone else will overdo it. I have to say that I have split many many tonne of redgum etc with it and really believe that it is a good machine. Although it can be stalled I am very happy with its capacity. I no longer worry about straight wood. I constantly see the leftovers of wood from other people and think that I would have taken that. I cut and take home redgum fork sections because this splitter will split them.

The other thing with a splitter is cost. It is cheap to run. With a chainsaw there is the cost of bars, chains and chain oil. All of which vary according to the timber cut and can be very high if cutting dirty dry wood. I know of a bit of redgum that is about 600mm X 600mm X 2400mm which would be dry(probably been lying there for 50 yrs). It is flat sided so has been milled in some way. I may get it one day but it may cost a lot to cut up because of the dirt content.

If you look at my original pic of the splitter you can see some split wood on the right side. The top 2 pieces are redgum house stumps 4inches square and probably 50 - 60 yr old. I got them from a house site where the house had been removed and sold. My splitter will break them into suitable bits easily. I often break pieces rather than get out the saw. The splitter only costs for petrol, oil and air filter etc. The cost does not change because the wood is dirty.

I do prefer to cut green wood for a number of reasons.

Clean. No buildup of dirt from lying on the ground, ants etc.
Easier to cut by far than dry wood. Chainsaws cut much longer and easier.
Not many other people are interested.
When the supply of dry wood is exhausted that is it, but another big branch / tree (green) may fall anytime.
I could not keep up with the supply of green wood along the roads in our area.

The issue with green wood is that it can be and usually is much harder to split and it cannot be burnt for about 2 years if split. It is also heavier to handle. Last Xmas I cut up the trunk of a green redgum lying on the ground (almost) with the help of SWMBO, her son and his wife. The base of the trunk was about 900mm diam. This was about 6km from my front gate. There were 3 trees there in total. We only cut from one. One of them was bridged across a waterway. Easy wood, cheap to get and close to home.

Dean

I'd remove the 100mm flat and get some 32, 40 or 50mm x 5mm, which ever fits in the flange and criss cross it on edge like I've drawn.

It will stiffen it up considerably.

DJ

That's an interesting solution to the problem. I did hint at something similar in an earlier post, but I suspect on reflection, it will still only strengthen the beam over it's length and not add much resistance to twisting.

A square box section would be ideal, but does allow for the slide, plus Dean has a UB. So I think flat bar between the flanges and additional angle to reinforce the front flange (along with the packer) should give a much more solid mast.

Regards
Paul